This page has only limited features, please log in for full access.

Prof. Nokwanda Makunga
Department of Botany and Zoology, Faculty of Science, Stellenbosch University, Stellenbosch, 7600, South Africa

Basic Info


Research Keywords & Expertise

0 Essential Oils
0 Natural Products
0 phytochemicals
0 alkaloids
0 medicinal plants

Fingerprints

medicinal plants
alkaloids
phytochemicals
Essential Oils
Natural Products

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 13 July 2021 in Antioxidants
Reads 0
Downloads 0

‘Wonderful’ pomegranate (Punica granatum L.) peel contains a wide range of phytochemicals including vitamins, dietary fibre, phenolic compounds, and antioxidant properties. Yet, it is often used as animal feed or discarded in landfills, which is not the best eco-friendly way to utilize this phenolic-rich bioresource. Finding novel ways of utilizing pomegranate peel waste could prove a more profitable and eco-friendlier alternative that is far more beneficial to the economy. Adding a blanching pre-treatment step at optimal conditions prior to processing of pomegranate peel aids in the inactivation of quality changing enzymes such as polyphenol oxidase (PPO) and peroxidase (POD), which are accountable for the degradation reactions that cause breakdown of nutrients and phytochemicals. This study aimed to determine the effect of blanching at 80 °C for 3 min on the yield, polyphenol content, antioxidant properties, enzyme inactivation, and antibacterial activity of ‘Wonderful’ pomegranate peel ethanolic extracts from three different harvest maturities (unripe, ripe, and over ripe), including a comprehensive characterization and quantification using liquid chromatography-mass spectrometry (LC-MS). The blanched unripe peel extracts exhibited the highest total phenolic content, total tannin content, 2,2-diphenyl-1-picryl hydrazyl (DPPH) antioxidant activity, 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity and ferric ion reducing antioxidant power (FRAP) at 14.0 mg gallic acid equivalent (GAE)/g dry mass (DM), 1.0 mg GAE/g DM, 359.1 µmol Trolox/g DM, 912.2 µmol Trolox/g DM and 802.5 µmol Trolox/g DM, respectively. There was significant (p< 0.05) decrease in PPO and POD activity of all blanched pomegranate peel extracts. The blanched unripe peel extracts had the lowest PPO activity at 0.2 U/g fresh weight (FW), with a 70% PPO inactivation compared to ripe and over ripe harvest, whereas the highest POD inactivation was recorded at 67% in over ripe peel extracts. All blanched peel extracts, irrespective of harvest maturity, had minimum inhibitory concentration (MIC) values at 160 µg/mL against all four bacteria strains tested, which included two Gram-positive bacterial strains (Bacillus subtilis ATCC 6051 and Staphylococcus aureus ATCC 12600) and two Gram-negative bacteria (Escherichia coli 11775 and Klebsiella pneumonia ATCC 13883). A total of 25 metabolites including phenolic acids (4), organic acids (1), flavonoids (4), ellagitannins (13), and other polyphenols (3) in all three pomegranate peel samples were tentatively identified after LC-MS profiling. The blanched unripe peel extracts showed significantly higher punicalin α and β, β punicalagin, catechin, epicatechin content at 414 mg/g, and 678 mg/g, 151 mg/g, 229 mg/g, respectively, compared to peel extracts from other harvest maturities. This study provides supportive information for the commercial utilization of pomegranate fruit peel as source of value-added ingredients for the development of novel food, cosmetics, and pharmacological products.

ACS Style

Tandokazi Magangana; Nokwanda Makunga; Chris la Grange; Maria Stander; Olaniyi Fawole; Umezuruike Opara. Blanching Pre-Treatment Promotes High Yields, Bioactive Compounds, Antioxidants, Enzyme Inactivation and Antibacterial Activity of ‘Wonderful’ Pomegranate Peel Extracts at Three Different Harvest Maturities. Antioxidants 2021, 10, 1119 .

AMA Style

Tandokazi Magangana, Nokwanda Makunga, Chris la Grange, Maria Stander, Olaniyi Fawole, Umezuruike Opara. Blanching Pre-Treatment Promotes High Yields, Bioactive Compounds, Antioxidants, Enzyme Inactivation and Antibacterial Activity of ‘Wonderful’ Pomegranate Peel Extracts at Three Different Harvest Maturities. Antioxidants. 2021; 10 (7):1119.

Chicago/Turabian Style

Tandokazi Magangana; Nokwanda Makunga; Chris la Grange; Maria Stander; Olaniyi Fawole; Umezuruike Opara. 2021. "Blanching Pre-Treatment Promotes High Yields, Bioactive Compounds, Antioxidants, Enzyme Inactivation and Antibacterial Activity of ‘Wonderful’ Pomegranate Peel Extracts at Three Different Harvest Maturities." Antioxidants 10, no. 7: 1119.

Journal article
Published: 08 June 2021 in Processes
Reads 0
Downloads 0

‘Wonderful’ pomegranate (Punica granatum L.) peel is rich in phytochemicals which are responsible for its strong antioxidant and antimicrobial activities, but it has low economic value as it is mainly discarded, causing an environmental waste management problem. To examine the best processing regime for pomegranate peel wastes, different solvents (ethanol, methanol and acetone) at various concentrations (50%, 70% and 100%) and blanching at 60, 80 and 100 °C for 1, 3 and 5 min, for each temperature, were tested. Ethanol at 70% (v/v) provided the highest extract yield, total phenolic and total tannin content at 29.46%, 10.61 ± 0.15, and 0.76 ± 0.02 mg GAE/g DM, respectively. Antioxidant activity using the 2,2 diphenyl-1-picryl hydrazyl assay (DPPH), ferric-reducing antioxidant power assay (FRAP) and 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay (ABTS) were reported at 243.97 ± 2.43, 478.04 ± 73.98 and 718.79 ± 2.42 µmol Trolox/g DM, respectively. A blanching temperature of 80 °C for 3 min led to the highest extract that had a total phenolic content of 12.22 ± 0.08 mg GAE/g DM and total tannin content of 1.06 ± 0.06 mg GAE/g DM. This extract also exhibited the best antioxidant activity for the DPPH, FRAP and ABTS assays. Two blanching temperatures, 80 or 100 °C, significantly reduced polyphenol oxidase and peroxidase activities (p< 0.05). Although blanched peel extracts showed a broad-spectrum activity against test bacteria, blanching at 80 °C for 3 or 5 min was most effective. Hot water blanching is thus a suitable environmentally friendly post-harvesting processing method for pomegranate peels that are intended for use as extracts in value-added products with good antioxidant and antibacterial effects.

ACS Style

Tandokazi Magangana; Nokwanda Makunga; Olaniyi Amos Fawole; Umezuruike Opara. Effect of Solvent Extraction and Blanching Pre-Treatment on Phytochemical, Antioxidant Properties, Enzyme Inactivation and Antibacterial Activities of ‘Wonderful’ Pomegranate Peel Extracts. Processes 2021, 9, 1012 .

AMA Style

Tandokazi Magangana, Nokwanda Makunga, Olaniyi Amos Fawole, Umezuruike Opara. Effect of Solvent Extraction and Blanching Pre-Treatment on Phytochemical, Antioxidant Properties, Enzyme Inactivation and Antibacterial Activities of ‘Wonderful’ Pomegranate Peel Extracts. Processes. 2021; 9 (6):1012.

Chicago/Turabian Style

Tandokazi Magangana; Nokwanda Makunga; Olaniyi Amos Fawole; Umezuruike Opara. 2021. "Effect of Solvent Extraction and Blanching Pre-Treatment on Phytochemical, Antioxidant Properties, Enzyme Inactivation and Antibacterial Activities of ‘Wonderful’ Pomegranate Peel Extracts." Processes 9, no. 6: 1012.

Original article
Published: 13 February 2021 in Plant Cell, Tissue and Organ Culture (PCTOC)
Reads 0
Downloads 0

Plants under different environmental regimes exhibit phenotypic plasticity, sometimes producing more secondary metabolites when microenvironmental conditions are manipulated but these responses may be species, cultivar and/or genotype dependent. To test the hypothesis of whether in vitro plants of S. rebaudiana Bertoni would accumulate higher amounts of steviol glycosides when plants were growing under salt and drought stress, cultivar ST2100 plants were used. We thus applied 25 to 100 mM NaCl and polyethylene glycol 6000 (PEG) at 2.5% to 10.0% (w/v) to generate different Murashige and Skoog (Physiol Plant 15:473–497, 1962) media. Microplant cultures were also profiled for stevioside, rebaudioside A and steviol via LC–MS. Essential oil chemicals and fatty acids were assessed using GC–MS. Finally, a chemometric analysis of ethanolic extracts produced from treated and control plants is presented from MSE fragmentation data and various phenolic acids were tentatively identified using ion fragmentation patterns. Increasing amounts of both NaCl and PEG led to poor growth and development in cultures of S. rebaudiana. For example, the 25 and 50 mM NaCl-treated plants had fewer roots in comparison to controls and at even higher concentrations (75 and 100 mM NaCl), plants did not to root. Poor in vitro organogenesis was more pronounced with PEG. For instance, when plants were placed on a 10% PEG-medium, the ability for shoot regeneration was lost and callus became more apparent. Increasing levels of NaCl and PEG were also correlated to lowered levels of rebaudioside A and stevioside. In relation to the control plants that had 0.054 mg g−1 FW of steviol, the 25 mM NaCl treatment group had highest levels of this compound, recorded at 0.156 mg g−1 FW. All other salt treatments led to trace amounts of this chemical (0.005–0.009 mg g−1 FW) and it was not detected in any of the PEG-treated plants, except for the controls. The PCA loadings plots exposed stevioside, rebaudioside E and a steviol glycoside derivative as the MS signals that contributed to discriminant clusters segregating controls from the NaCl-treated groups. For PEG, segregation in the PCA is mostly influenced by dicaffeoylquinic acid as a marker ion, separating the controls from the treatment groups. PEG-treatments caused more prominent changes to the essential oil chemistry of Stevia plants. This was evident when 7.5 or 10% PEG was applied as sabinene, α-terpinolene, n-amyl isovalerate, 7-octen-4-ol, α-bergamotene, junipene, (+)-calarene, α-cadinol, β-pinene, α-bergamotene, (+)-calarene and junipene became undetectable. Changes of this nature may be undesirable when aromatic oils of S. rebaudiana are targetted for commercial markets as our data suggest adjustment to stresses may negatively impact volatile compounds leading to a loss of bioactive aromatic compounds. This study reports, for the first time, the effects of salinity and drought conditions in vitro on changed essential oil profiles of S. rebaudiana, providing new insights into the effects of stress on the essential oil chemistry of S. rebaudiana.

ACS Style

T. P. Magangana; M. A. Stander; N. A. Masondo; N. P. Makunga. Steviol glycoside content and essential oil profiles of Stevia rebaudiana Bertoni in response to NaCl and polyethylene glycol as inducers of salinity and drought stress in vitro. Plant Cell, Tissue and Organ Culture (PCTOC) 2021, 145, 1 -18.

AMA Style

T. P. Magangana, M. A. Stander, N. A. Masondo, N. P. Makunga. Steviol glycoside content and essential oil profiles of Stevia rebaudiana Bertoni in response to NaCl and polyethylene glycol as inducers of salinity and drought stress in vitro. Plant Cell, Tissue and Organ Culture (PCTOC). 2021; 145 (1):1-18.

Chicago/Turabian Style

T. P. Magangana; M. A. Stander; N. A. Masondo; N. P. Makunga. 2021. "Steviol glycoside content and essential oil profiles of Stevia rebaudiana Bertoni in response to NaCl and polyethylene glycol as inducers of salinity and drought stress in vitro." Plant Cell, Tissue and Organ Culture (PCTOC) 145, no. 1: 1-18.

Review
Published: 14 October 2020 in Molecules
Reads 0
Downloads 0

Pomegranate peel has substantial amounts of phenolic compounds, such as hydrolysable tannins (punicalin, punicalagin, ellagic acid, and gallic acid), flavonoids (anthocyanins and catechins), and nutrients, which are responsible for its biological activity. However, during processing, the level of peel compounds can be significantly altered depending on the peel processing technique used, for example, ranging from 38.6 to 50.3 mg/g for punicalagins. This review focuses on the influence of postharvest processing factors on the pharmacological, phytochemical, and nutritional properties of pomegranate (Punica granatum L.) peel. Various peel drying strategies (sun drying, microwave drying, vacuum drying, and oven drying) and different extraction protocols (solvent, super-critical fluid, ultrasound-assisted, microwave-assisted, and pressurized liquid extractions) that are used to recover phytochemical compounds of the pomegranate peel are described. A total phenolic content of 40.8 mg gallic acid equivalent (GAE)/g DM was recorded when sun drying was used, but the recovery of the total phenolic content was higher at 264.3 mg TAE/g when pressurised liquid extraction was performed. However, pressurised liquid extraction is costly due to the high initial investment costs and the limited possibility of carrying out selective extractions of organic compounds from complex peel samples. The effects of these methods on the phytochemical profiles of pomegranate peel extracts are also influenced by the cultivar and conditions used, making it difficult to determine best practice. For example, oven drying at 60 °C resulted in higher levels of punicalin of 888.04 mg CE/kg DM compared to those obtained 40 °C of 768.11 mg CE/kg DM for the Wonderful cultivar. Processes that are easy to set up, cost-effective, and do not compromise the quality and safety aspects of the peel are, thus, more desirable. From the literature survey, we identified a lack of studies testing pretreatment protocols that may result in a lower loss of the valuable biological compounds of pomegranate peels to allow for full exploitation of their health-promoting properties in potentially new value-added products.

ACS Style

Tandokazi Pamela Magangana; Nokwanda Pearl Makunga; Olaniyi Amos Fawole; Umezuruike Linus Opara. Processing Factors Affecting the Phytochemical and Nutritional Properties of Pomegranate (Punica granatum L.) Peel Waste: A Review. Molecules 2020, 25, 4690 .

AMA Style

Tandokazi Pamela Magangana, Nokwanda Pearl Makunga, Olaniyi Amos Fawole, Umezuruike Linus Opara. Processing Factors Affecting the Phytochemical and Nutritional Properties of Pomegranate (Punica granatum L.) Peel Waste: A Review. Molecules. 2020; 25 (20):4690.

Chicago/Turabian Style

Tandokazi Pamela Magangana; Nokwanda Pearl Makunga; Olaniyi Amos Fawole; Umezuruike Linus Opara. 2020. "Processing Factors Affecting the Phytochemical and Nutritional Properties of Pomegranate (Punica granatum L.) Peel Waste: A Review." Molecules 25, no. 20: 4690.

Journal article
Published: 10 September 2020 in Molecules
Reads 0
Downloads 0

Dodonaea viscosa Jacq (Sapindaceae) is a medicinal plant with a worldwide distribution. The species has undergone enormous taxonomic changes which caused confusion amongst plant users. In Kenya, for example, two varieties are known to exist based on morphology, i.e., D. viscosa var. viscosa along the coast, and D. viscosa var. angustifolia in the Kenyan inland. These two taxa are recognized as distinct species in some reports. This prompted us to apply metabolomics to understand the relationship among naturally occurring populations of D. viscosa in Kenya, and to identify compounds that can assist in taxonomic delineation of the different varieties of D. viscosa from different parts of Kenya. The phytochemical variability of Kenyan D. viscosa var. angustifolia populations collected from four different geographical regions (Nanyuki, Machakos, Nairobi, and Narok) and one coastal D. viscosa var. viscosa (the Gazi) were analyzed by LC-MS using a metabolomics-driven approach. Four known compounds, two diterpenoids (dodonic acid (1), hautriwaic acid lactone (3), and two flavonoids (5,7,4′,5′-tetrahydroxy-3,6,2′-trimethoxyflavone (2) and catechin (4)) were isolated and purified from the Gazi coastal collection. The presence of these compounds and their relative abundance in other populations was determined by LC-MS analyses. Multivariate statistical analyses of LC-MS data was used for the visualization of the patterns of variation and identification of additional compounds. Eleven discriminant compounds responsible for separating chemometric clusters were tentatively identified. In an antimicrobial assay, hautriwaic acid lactone (3) and catechin (4) were the most active compounds followed by the extract from the coastal (Gazi) population. The clustering pattern of the five populations of D. viscosa suggested that the metabolite profiles were influenced by geo-environmental conditions and did not support the current classification of D. viscosa based on morphology. This study disputes the current classification of D. viscosa in Kenya and recommends revision using tools such as molecular phylogenetics.

ACS Style

Magrate M. Kaigongi; Catherine W. Lukhoba; Purity J. Ochieng‘; Malcolm Taylor; Abiy Yenesew; Nokwanda P. Makunga. LC-MS-Based Metabolomics for the Chemosystematics of Kenyan Dodonaea viscosa Jacq (Sapindaceae) Populations. Molecules 2020, 25, 4130 .

AMA Style

Magrate M. Kaigongi, Catherine W. Lukhoba, Purity J. Ochieng‘, Malcolm Taylor, Abiy Yenesew, Nokwanda P. Makunga. LC-MS-Based Metabolomics for the Chemosystematics of Kenyan Dodonaea viscosa Jacq (Sapindaceae) Populations. Molecules. 2020; 25 (18):4130.

Chicago/Turabian Style

Magrate M. Kaigongi; Catherine W. Lukhoba; Purity J. Ochieng‘; Malcolm Taylor; Abiy Yenesew; Nokwanda P. Makunga. 2020. "LC-MS-Based Metabolomics for the Chemosystematics of Kenyan Dodonaea viscosa Jacq (Sapindaceae) Populations." Molecules 25, no. 18: 4130.

Review
Published: 22 August 2020 in Biomolecules
Reads 0
Downloads 0

Cytokinins (CKs) are a chemically diverse class of plant growth regulators, exhibiting wide-ranging actions on plant growth and development, hence their exploitation in agriculture for crop improvement and management. Their coordinated regulatory effects and cross-talk interactions with other phytohormones and signaling networks are highly sophisticated, eliciting and controlling varied biological processes at the cellular to organismal levels. In this review, we briefly introduce the mode of action and general molecular biological effects of naturally occurring CKs before highlighting the great variability in the response of fruit crops to CK-based innovations. We present a comprehensive compilation of research linked to the application of CKs in non-model crop species in different phases of fruit production and management. By doing so, it is clear that the effects of CKs on fruit set, development, maturation, and ripening are not necessarily generic, even for cultivars within the same species, illustrating the magnitude of yet unknown intricate biochemical and genetic mechanisms regulating these processes in different fruit crops. Current approaches using genomic-to-metabolomic analysis are providing new insights into the in planta mechanisms of CKs, pinpointing the underlying CK-derived actions that may serve as potential targets for improving crop-specific traits and the development of new solutions for the preharvest and postharvest management of fruit crops. Where information is available, CK molecular biology is discussed in the context of its present and future implications in the applications of CKs to fruits of horticultural significance.

ACS Style

Adeyemi O. Aremu; Olaniyi A. Fawole; Nokwanda P. Makunga; Nqobile A. Masondo; Mack Moyo; Nana M. D. Buthelezi; Stephen O. Amoo; Lukáš Spíchal; Karel Doležal. Applications of Cytokinins in Horticultural Fruit Crops: Trends and Future Prospects. Biomolecules 2020, 10, 1222 .

AMA Style

Adeyemi O. Aremu, Olaniyi A. Fawole, Nokwanda P. Makunga, Nqobile A. Masondo, Mack Moyo, Nana M. D. Buthelezi, Stephen O. Amoo, Lukáš Spíchal, Karel Doležal. Applications of Cytokinins in Horticultural Fruit Crops: Trends and Future Prospects. Biomolecules. 2020; 10 (9):1222.

Chicago/Turabian Style

Adeyemi O. Aremu; Olaniyi A. Fawole; Nokwanda P. Makunga; Nqobile A. Masondo; Mack Moyo; Nana M. D. Buthelezi; Stephen O. Amoo; Lukáš Spíchal; Karel Doležal. 2020. "Applications of Cytokinins in Horticultural Fruit Crops: Trends and Future Prospects." Biomolecules 10, no. 9: 1222.

Journal article
Published: 21 July 2020 in Plants
Reads 0
Downloads 0

Zanthoxylum paracanthum Kokwaro (Rutaceae) is an endemic Kenyan and Tanzanian plant used in folk medicine by local populations. Although other Zanthoxylum species have been studied, only Z. paracantum stem extracts have been profiled, even though the roots are also used as herbal remedies. As root extracts may be another source of pharmaceutical compounds, the CH2Cl2/MeOH (1:1) root bark extract was studied in this report. Eight root bark compounds were isolated and their structural identities were confirmed by mass spectrometry (MS) and nuclear magnetic resonance (NMR) (using COSY, HSQC, NOESY and HMBC) analyses. The structural identities were determined as follows: the fatty acid—myristic acid (1); the sterol—stigmasterol (2); the lignan—sesamin (3); two β-carboline alkaloids—10-methoxycanthin-6-one (6) and canthin-6-one (7); and three phenanthridine alkaloids—8-acetonyldihydrochelerythrine (4), arnottianamide (5) and 8-oxochelerythrine (8). Some of these compounds were identified in the species for the first time. These compounds and the extract were then tested in vitro against methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 29213) and Candida albicans (ATCC 10231) before tests for antiproliferative activity against the human breast cancer (HCC 1395), human prostate cancer (DU 145) and normal (Vero E6) cell lines were conducted. Minimum inhibition concentration values of 3.91, 1.95, 0.98 and 7.81 µg/mL against MRSA, S. aureus, E. coli and C. albicans, respectively, were recorded. Among the isolates, canthin-6-one was the most active, followed by 10-methoxycanthin-6-one. The root extract and some of the compounds also had antiproliferative activity against the HCC 1395 cell line. Stigmasterol and canthin-6-one had IC50 values of 7.2 and 0.42. The root bark extract also showed activity, at 8.12 µg/mL, against the HCC 1395 cells. Out of the chemical isolates, 10-methoxycanthin-6-one and canthin-6-one showed the strongest inhibition of the DU 145 cells. The root extract had significant antimicrobial and antiproliferative activities, supporting the traditional use of this plant in treating microbial infections and cancer-related ailments.

ACS Style

Magrate M. Kaigongi; Catherine W. Lukhoba; Souaibou Yaouba; Nokwanda P. Makunga; Joseph Githiomi; Abiy Yenesew. In Vitro Antimicrobial and Antiproliferative Activities of the Root Bark Extract and Isolated Chemical Constituents of Zanthoxylum paracanthum Kokwaro (Rutaceae). Plants 2020, 9, 920 .

AMA Style

Magrate M. Kaigongi, Catherine W. Lukhoba, Souaibou Yaouba, Nokwanda P. Makunga, Joseph Githiomi, Abiy Yenesew. In Vitro Antimicrobial and Antiproliferative Activities of the Root Bark Extract and Isolated Chemical Constituents of Zanthoxylum paracanthum Kokwaro (Rutaceae). Plants. 2020; 9 (7):920.

Chicago/Turabian Style

Magrate M. Kaigongi; Catherine W. Lukhoba; Souaibou Yaouba; Nokwanda P. Makunga; Joseph Githiomi; Abiy Yenesew. 2020. "In Vitro Antimicrobial and Antiproliferative Activities of the Root Bark Extract and Isolated Chemical Constituents of Zanthoxylum paracanthum Kokwaro (Rutaceae)." Plants 9, no. 7: 920.

Journal article
Published: 13 February 2020 in Antioxidants
Reads 0
Downloads 0

Extracts of Sutherlandia frutescens (cancer bush) exhibit considerable qualitative and quantitative chemical variability depending on their natural wild origins. The purpose of this study was thus to determine bioactivity of extracts from different regions using in vitro antioxidant and anti-cancer assays. Extracts of the species are complex and are predominantly composed of a species-specific set of triterpene saponins (cycloartanol glycosides), the sutherlandiosides, and flavonoids (quercetin and kaempferol glycosides), the sutherlandins. For the Folin-Ciocalteu phenolics test values of 93.311 to 125.330 mg GAE/g DE were obtained. The flavonoids ranged from 54.831 to 66.073 mg CE/g DE using the aluminum chloride assay. Extracts from different sites were also assayed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging method and ferric reducing anti-oxidant power (FRAP) methods. This was followed by an in vitro Cell Titer-Glo viability assay of various ecotypes using the DLD-1 colon cancer cell line. All test extracts displayed anti-oxidant activity through the DPPH• radical scavenging mechanism, with IC50 values ranging from 3.171 to 7.707 µg·mL−1. However, the degree of anti-oxidant effects differed on a chemotypic basis with coastal plants from Gansbaai and Pearly Beach (Western Cape) exhibiting superior activity whereas the Victoria West inland group from the Northern Cape, consistently showed the weakest anti-oxidant activity for both the DPPH• and FRAP methods. All extracts showed cytotoxicity on DLD-1 colon cancer cells at the test concentration of 200 µg·mL−1 but Sutherlandia plants from Colesburg (Northern Cape) exhibited the highest anti-cancer activity. These findings confirm that S. frutescens specimens display variability in their bioactive capacities based on their natural location, illustrating the importance of choosing relevant ecotypes for medicinal purposes.

ACS Style

Samkele Zonyane; Olaniyi A. Fawole; Chris La Grange; Maria A. Stander; Umezuruike L. Opara; Nokwanda P. Makunga. The Implication of Chemotypic Variation on the Anti-Oxidant and Anti-Cancer Activities of Sutherlandia frutescens (L.) R.Br. (Fabaceae) from Different Geographic Locations. Antioxidants 2020, 9, 152 .

AMA Style

Samkele Zonyane, Olaniyi A. Fawole, Chris La Grange, Maria A. Stander, Umezuruike L. Opara, Nokwanda P. Makunga. The Implication of Chemotypic Variation on the Anti-Oxidant and Anti-Cancer Activities of Sutherlandia frutescens (L.) R.Br. (Fabaceae) from Different Geographic Locations. Antioxidants. 2020; 9 (2):152.

Chicago/Turabian Style

Samkele Zonyane; Olaniyi A. Fawole; Chris La Grange; Maria A. Stander; Umezuruike L. Opara; Nokwanda P. Makunga. 2020. "The Implication of Chemotypic Variation on the Anti-Oxidant and Anti-Cancer Activities of Sutherlandia frutescens (L.) R.Br. (Fabaceae) from Different Geographic Locations." Antioxidants 9, no. 2: 152.

Journal article
Published: 27 March 2019 in Industrial Crops and Products
Reads 0
Downloads 0

Sutherlandia frutescens (syn. Lessertia frutescens), an indigenous southern African species, is important for the local and global phytomedicine's industry. As farming of medicinal plants in South Africa is not extensive, wild populations are also used as a source of material to bulk available cultivated yields prior to industrial processing. This may cause inconsistency in the quality of medicinal products derived from this species, inducing discrepancies in the plant’s therapeutic profile. The current study aimed to elucidate the phytochemical variations among S. frutescens plants growing in different geographical localities, especially in areas which have not been studied before. One set of extracts were generated using a 50% acetonitrile and formic acid solution (0.1%) (v/v). By using a targeted metabolomics approach, two major phytochemical groups, sutherlandins and sutherlandiosides were used to display metabolite-based clusters after LC–MS/MS analysis. Plants from different geographical locations grouped into separate chemical lineages. Another set of ethanol and aqueous extracts of pooled leaf materials were screened for their toxicity effect on the hatching rate of zebrafish embryos and mortality of larvae at different concentrations, ranging from 5 to 300 μg ml−1. We also calculated the LC50 values using a zebrafish microplate bioassay and this value was 297.57 μg ml−1 for the water extract. The aqueous extracts were relatively less toxic compared to ethanol extracts (LC50 value of 40.54 μg ml−1). Both the hatching rate and mortality were negatively affected by increasing extract dosages. The highest concentrations, between 200 to 300 μg ml−1, caused acute lethal effects for both extract types. This study adds additional evidence of the cytotoxicity reported by others in this species and will further aid in the domestication of S. frutescens.

ACS Style

Samkele Zonyane; Longsheng Chen; Min-Jie Xu; Zhu-Nan Gong; Shuwen Xu; Nokwanda P. Makunga. Geographic-based metabolomic variation and toxicity analysis of Sutherlandia frutescens L. R.Br. – An emerging medicinal crop in South Africa. Industrial Crops and Products 2019, 133, 414 -423.

AMA Style

Samkele Zonyane, Longsheng Chen, Min-Jie Xu, Zhu-Nan Gong, Shuwen Xu, Nokwanda P. Makunga. Geographic-based metabolomic variation and toxicity analysis of Sutherlandia frutescens L. R.Br. – An emerging medicinal crop in South Africa. Industrial Crops and Products. 2019; 133 ():414-423.

Chicago/Turabian Style

Samkele Zonyane; Longsheng Chen; Min-Jie Xu; Zhu-Nan Gong; Shuwen Xu; Nokwanda P. Makunga. 2019. "Geographic-based metabolomic variation and toxicity analysis of Sutherlandia frutescens L. R.Br. – An emerging medicinal crop in South Africa." Industrial Crops and Products 133, no. : 414-423.

Journal article
Published: 26 March 2019 in Plant Science
Reads 0
Downloads 0

Tanshinones are the main bioactive diterpenes in Salvia miltiorrhiza Bunge, are widely used for treating cardiovascular and cerebrovascular diseases. However, the biosynthetic mechanisms of these compounds have not yet been fully explained. In this study, a transcription factor named SmWRKY2 was isolated and functionally characterized. Multiple sequence analysis indicated it was classified into subgroup I of the WRKY family. Expression pattern showed that SmWRKY2 was mainly expressed in the stem and leaf and was inducible by methyl jasmonate (MeJA) treatment. Subcellular localization showed that SmWRKY2 was localized in the nucleus. Overexpression of SmWRKY2 in S. miltiorrhiza hairy roots significantly increased the expression of SmDXS2 and SmCPS, resulting in increased accumulation of tanshinones and the highest total tanshinone content was detected in OE-SmWRKY2-1 line, which was 1.83 times of the control. Meanwhile, tanshinone production was slightly reduced in the antisense-SmWRKY2 line. Dual-Luciferase assay showed that SmWRKY2 can positively regulate SmDXS2 and SmCPS expression, However, Y1H and EMSA experiments indicate that SmWRKY2 only binds to the W-box of the SmCPS promoter. Our study shows that SmWRKY2 is a positive regulator of tanshinone biosynthesis by mainly activating SmCPS. This study thus sheds new light on the regulatory role of SmWRKY2 in tanshinone biosynthesis.

ACS Style

Changping Deng; Xiaolong Hao; Min Shi; Rong Fu; Yao Wang; Yi Zhang; Wei Zhou; Yue Feng; Nokwanda P. Makunga; Guoyin Kai. Tanshinone production could be increased by the expression of SmWRKY2 in Salvia miltiorrhiza hairy roots. Plant Science 2019, 284, 1 -8.

AMA Style

Changping Deng, Xiaolong Hao, Min Shi, Rong Fu, Yao Wang, Yi Zhang, Wei Zhou, Yue Feng, Nokwanda P. Makunga, Guoyin Kai. Tanshinone production could be increased by the expression of SmWRKY2 in Salvia miltiorrhiza hairy roots. Plant Science. 2019; 284 ():1-8.

Chicago/Turabian Style

Changping Deng; Xiaolong Hao; Min Shi; Rong Fu; Yao Wang; Yi Zhang; Wei Zhou; Yue Feng; Nokwanda P. Makunga; Guoyin Kai. 2019. "Tanshinone production could be increased by the expression of SmWRKY2 in Salvia miltiorrhiza hairy roots." Plant Science 284, no. : 1-8.

Journal article
Published: 06 February 2019 in Journal of Ethnopharmacology
Reads 0
Downloads 0

Limitations of clinical antifungal treatments and drug-resistance are drivers of the search for novel antifungal strategies. Extracts prepared from the tubers of the medicinal plant, Pelargonium sidoides, are known for their antiviral and antibacterial activities and are used in ethnomedicine for the treatment of acute respiratory infections. Their impact on fungi has not been well characterised. Here, we provide a first report on the antifungal activity of a P. sidoides aerial tissue extract against Cryptococcus neoformans as well as the effects of both tuber and aerial tissue extracts on selected virulence factors. Novel antimicrobial strategies that target multiple cellular pathways or make use of anti-pathogenic compounds that inhibit virulence factors have been proposed. This work aimed to evaluate P. sidoides plant parts for their anticryptococcal activity and antipathogenic properties on selected virulence factors. The antifungal activity of crude P. sidoides tuber and aerial tissue extracts (15% m/m ethanol) were compared using a modified colourimetric antifungal susceptibility test. Fungicidal activity of the extracts was confirmed by plate counts. To test yeast resistance to the extracts, it was conditioned by multiple passages in sub-lethal doses followed by antifungal susceptibility testing. Cytotoxicity of the extracts was tested with a blood agar haemolysis assay. Extracts were evaluated for the presence of multiple bioactive compounds by solid-phase fractionation and visualisation by thin-layer chromatography in combination with bioassays. The influence of extracts on the production of the polysaccharide capsule, ergosterol content as well as laccase and urease activities were also evaluated. Cell surface variations after extract exposure were visualised by scanning electron microscopy (SEM). Both tuber and aerial tissue extracts were fungicidal and contained multiple bioactive compounds which constrained the development of antifungal resistance. No haemolytic activity was observed, and the extracts did not appear to target ergosterol biosynthesis. However, the extracts displayed anti-pathogenic potential by significantly inhibiting laccase and urease activity while also significantly reducing capsule size. SEM revealed notable cell surface variations and provided support for the observed reduction in capsule size. Our results provide support to the exploration of medicinal plants as sources of alternative antifungal therapies and the potential use of multicomponent inhibition and or virulence attenuation for next-generation treatment strategies. Our data also provide relevant information that may support the further use of P. sidoides in traditional medicines as well as in commercialised phytopharmaceuticals.

ACS Style

Shakier Samie; Kim M. Trollope; Lydia-Marié Joubert; Nokwanda P. Makunga; Heinrich Volschenk. The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts. Journal of Ethnopharmacology 2019, 235, 122 -132.

AMA Style

Shakier Samie, Kim M. Trollope, Lydia-Marié Joubert, Nokwanda P. Makunga, Heinrich Volschenk. The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts. Journal of Ethnopharmacology. 2019; 235 ():122-132.

Chicago/Turabian Style

Shakier Samie; Kim M. Trollope; Lydia-Marié Joubert; Nokwanda P. Makunga; Heinrich Volschenk. 2019. "The antifungal and Cryptococcus neoformans virulence attenuating activity of Pelargonium sidoides extracts." Journal of Ethnopharmacology 235, no. : 122-132.

Review article
Published: 10 November 2018 in South African Journal of Botany
Reads 0
Downloads 0

The review focuses on acetylcholinesterase (AChE) inhibition of extracts and compounds from southern African plants. We provide a detailed inventory of southern African plants used in the treatment of central nervous system (CNS) and memory-related disorders that are potential candidates for novel AChE inhibitors. This was achieved through a detailed literature search using web-based database searches including Google Scholar, Scopus and Web of Science (WoS) as well as ethnobotanical literature on southern African medicinal plants. Bibliometric analysis was performed on the data mined from WoS. In addition, we reviewed the methods used to determine AChE activity and highlighted the success and potential of alkaloids from the Amaryllidaceae. Our findings revealed about 200 southern African medicinal plants that are used for CNS and memory-related disorders. Approximately, 65 southern African plants have been evaluated for AChE inhibitory activity even though the majority of these plants do not have an ethnobotanical basis for such evaluation. Several extracts (e.g. Ammocharis coranica (KerGawl.) Herb., Lannea schweinfurthii Engl, Scadoxus puniceus (L.) Friis & Nordal, Xysmalobium undulatum (L.) W.T.Aiton.) have been found to demonstrate noteworthy (IC50 ≤ 1 μg/ml) AChE inhibitory activity. Moreover, 30 compounds have been isolated in an attempt to discover AChE inhibitors from southern African plants. The most active (IC50 ≤ 12 μM) compounds were isolated from Crinum moorei Hook. f., Scadoxus puniceus and Acacia nilotica (L.) Willd. ex Del. subspecies kraussiana (Benth.). Thus far, very few South African studies have looked at the ecological and environmental impact of both naturally occurring and applied AChE inhibitors (e.g. organophosphate and carbamate insecticides) and no studies have considered medical applications other than in Alzheimer's disease (AD) therapy. Furthermore, most of these studies have mainly used an in vitro approach directed at developing treatments of age-related dementia such as AD, despite the decline in pharmaceutical interest of AChE inhibitors in the treatment of AD. It is also apparent that no further steps are taken towards the investigation of in vivo studies and clinical trials. In addition to these existing gaps, the pharmacodynamic and pharmacokinetic studies also need to be adequately addressed in order to generate more coordinated and focused research.

ACS Style

Nqobile Masondo; G.I. Stafford; A.O. Aremu; N.P. Makunga. Acetylcholinesterase inhibitors from southern African plants: An overview of ethnobotanical, pharmacological potential and phytochemical research including and beyond Alzheimer's disease treatment. South African Journal of Botany 2018, 120, 39 -64.

AMA Style

Nqobile Masondo, G.I. Stafford, A.O. Aremu, N.P. Makunga. Acetylcholinesterase inhibitors from southern African plants: An overview of ethnobotanical, pharmacological potential and phytochemical research including and beyond Alzheimer's disease treatment. South African Journal of Botany. 2018; 120 ():39-64.

Chicago/Turabian Style

Nqobile Masondo; G.I. Stafford; A.O. Aremu; N.P. Makunga. 2018. "Acetylcholinesterase inhibitors from southern African plants: An overview of ethnobotanical, pharmacological potential and phytochemical research including and beyond Alzheimer's disease treatment." South African Journal of Botany 120, no. : 39-64.

Journal article
Published: 05 October 2018 in BMC Complementary and Alternative Medicine
Reads 0
Downloads 0

Sutherlandia frutescens is one of the most promising commercialized, indigenous and medicinal plants of South Africa that is used as an immune-booster, and a traditional treatment for cancer. However, few studies report on its toxicology and dosage in vivo. There is still room to better understand its cytotoxicity effects in animal systems. We prepared two extracts, one with 80% (v/v) ethanol, and the other, with water. Both were studied to determine the maximum tolerable concentration when extracts were applied at 0 to 200 μg/ml to a Tuebingen zebrafish embryo line. The development of zebrafish embryos after 24 h post fertilization (hpf) was studied. A concentration range of 5 μg/ml to 50 μg/ml was then chosen to monitor the ontological development of cultured embryos. A liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method was used to study the differences of the two experimental extracts. Chemical variation between the extracts was illustrated using chemometrics. Both extracts led to bleeding and pericardial cyst formation when applied at high concentrations to the zebrafish embryo culture. Chronic teratogenic toxicities, leading to pericardial edema, yolk sac swelling, and other abnormal developmental characteristics, were detected. The aqueous extracts of S. frutescens were less toxic to the larvae than the ethanol extracts, validating preference for aqueous preparations when used in traditional medicine. Chemical differences between the water extracts and alcoholic extracts were analysed using LC-MS/MS. A supervised metabolomics approach, targeting the sutherlandiosides and sutherlandins using orthogonal partial least squares-discriminant analysis (OPLS-DA), illustrated that sutherlandiosides were the main chemical features that can be used to distinguish between the two extracts, despite the extracts being highly similar in their chemical constituents. The water extract caused less cytotoxic and abnormal developmental effects compared to the ethanolic extract, and, this is likely due to differences in concentrations of extracted chemicals rather than the chemical profile per se. This study provides more evidence of cytotoxicity effects linked to S. frutescens using the zebrafish embryo bioassay as a study tool.

ACS Style

Longsheng Chen; Minjie Xu; Zhunan Gong; Samkele Zonyane; Shuwen Xu; Nokwanda P. Makunga. Comparative cardio and developmental toxicity induced by the popular medicinal extract of Sutherlandia frutescens (L.) R.Br. detected using a zebrafish Tuebingen embryo model. BMC Complementary and Alternative Medicine 2018, 18, 273 .

AMA Style

Longsheng Chen, Minjie Xu, Zhunan Gong, Samkele Zonyane, Shuwen Xu, Nokwanda P. Makunga. Comparative cardio and developmental toxicity induced by the popular medicinal extract of Sutherlandia frutescens (L.) R.Br. detected using a zebrafish Tuebingen embryo model. BMC Complementary and Alternative Medicine. 2018; 18 (1):273.

Chicago/Turabian Style

Longsheng Chen; Minjie Xu; Zhunan Gong; Samkele Zonyane; Shuwen Xu; Nokwanda P. Makunga. 2018. "Comparative cardio and developmental toxicity induced by the popular medicinal extract of Sutherlandia frutescens (L.) R.Br. detected using a zebrafish Tuebingen embryo model." BMC Complementary and Alternative Medicine 18, no. 1: 273.

Original article
Published: 03 April 2018 in Plant Cell, Tissue and Organ Culture (PCTOC)
Reads 0
Downloads 0

The commercialization of Stevia rebaudiana Bertoni (Asteraceae) extracts as a natural sweetener is driving interest in the use of in vitro propagation systems as an alternative source of steviol glycosides. Out of this suite of chemicals, stevioside is the most abundant but rebaudioside A is the sweetest. We established an in vitro propagation method from germinated seedlings on a Murashige and Skoog (MS) (Physiol Plant 15:473–497, 1962) medium with aims to study the effects of nitrogen and phosphate on the growth and metabolite profiles of S. rebaudiana plants. Generally, NH4NO3 is supplied at a concentration of 20.61 mM in MS medium and together with 18.79 mM KNO3, provide nitrogen to in vitro growing plants. In this study, we used a range of 0.3–72.1 mM NH4NO3 and 9.4–65.8 mM KNO3 and generated six different media with altered nitrogen. Similarly, six different concentrations of KH2PO4, ranging from 0.6 to 4.4 mM were tested for the phosphate treatments and the control medium had 1.25 mM KH2PO4. By reducing the nitrogen and phosphate levels to half, respectively, this led to the tallest plants. Increasing concentrations of nitrogen in the medium significantly lowered the amount of rebaudioside A as plants on the control medium accumulated 270 mg g−1 rebaudioside A compared to those that were on a medium with 3.5 times the nitrogen supply (30 mg g−1 rebaudiose A). Steviol increased with increasing nitrogen available to the microplants. The highest levels of stevioside (740 mg g−1) quantified was linked to microplants on a medium with half the phosphate concentration. To further assess changes to the metabolomic profiles of treated microplants, LC–MS/MS was used in combination with multivariate statistical analyses. Two distinct clusters were revealed after principal component analysis. Steviol hydrate, stevioside hydrate and rebaudioside A contributed significantly to the separation of phosphate-treated plants from those with variable nitrogen concentrations. Chlorogenic acid and its derivatives were linked to changing phosphate concentrations. The clustering suggests different molecular mechanisms at play that are affected by nitrogen and phosphate supply which serve to alter secondary metabolic flux, resulting in different chemical profiles.

ACS Style

Tandokazi P. Magangana; Marietjie A. Stander; Nokwanda P. Makunga. Effect of nitrogen and phosphate on in vitro growth and metabolite profiles of Stevia rebaudiana Bertoni (Asteraceae). Plant Cell, Tissue and Organ Culture (PCTOC) 2018, 134, 141 -151.

AMA Style

Tandokazi P. Magangana, Marietjie A. Stander, Nokwanda P. Makunga. Effect of nitrogen and phosphate on in vitro growth and metabolite profiles of Stevia rebaudiana Bertoni (Asteraceae). Plant Cell, Tissue and Organ Culture (PCTOC). 2018; 134 (1):141-151.

Chicago/Turabian Style

Tandokazi P. Magangana; Marietjie A. Stander; Nokwanda P. Makunga. 2018. "Effect of nitrogen and phosphate on in vitro growth and metabolite profiles of Stevia rebaudiana Bertoni (Asteraceae)." Plant Cell, Tissue and Organ Culture (PCTOC) 134, no. 1: 141-151.

Journal article
Published: 01 March 2018 in South African Journal of Botany
Reads 0
Downloads 0
ACS Style

M.J. Hoffman; G.I. Stafford; N.P. Makunga. The role of alkaloids in chemical defence in Clivia miniata (Amaryllidaceae) against herbivory by Brithys crini. South African Journal of Botany 2018, 115, 319 -320.

AMA Style

M.J. Hoffman, G.I. Stafford, N.P. Makunga. The role of alkaloids in chemical defence in Clivia miniata (Amaryllidaceae) against herbivory by Brithys crini. South African Journal of Botany. 2018; 115 ():319-320.

Chicago/Turabian Style

M.J. Hoffman; G.I. Stafford; N.P. Makunga. 2018. "The role of alkaloids in chemical defence in Clivia miniata (Amaryllidaceae) against herbivory by Brithys crini." South African Journal of Botany 115, no. : 319-320.

Journal article
Published: 01 March 2016 in South African Journal of Botany
Reads 0
Downloads 0
ACS Style

A. Rautenbach; R. Henriques; G.I. Stafford; N.P. Makunga. Investigating a potential adjuvent remedy for cancer treatment: LC/MS based methods to differentiate and assess chemical composition of wild populations of Dodonaea viscosa. South African Journal of Botany 2016, 103, 305 .

AMA Style

A. Rautenbach, R. Henriques, G.I. Stafford, N.P. Makunga. Investigating a potential adjuvent remedy for cancer treatment: LC/MS based methods to differentiate and assess chemical composition of wild populations of Dodonaea viscosa. South African Journal of Botany. 2016; 103 ():305.

Chicago/Turabian Style

A. Rautenbach; R. Henriques; G.I. Stafford; N.P. Makunga. 2016. "Investigating a potential adjuvent remedy for cancer treatment: LC/MS based methods to differentiate and assess chemical composition of wild populations of Dodonaea viscosa." South African Journal of Botany 103, no. : 305.

Journal article
Published: 13 March 2014 in BMC Complementary and Alternative Medicine
Reads 0
Downloads 0

Salvia africana-lutea L., an important medicinal sage used in the Western Cape (South Africa), can be termed a ‘broad-spectrum remedy’ suggesting the presence of a multiplicity of bioactive metabolites. This study aimed at assessing wild S. africana-lutea populations for chemotypic variation and anti-Fusarium properties. Samples were collected from four wild growing population sites (Yzerfontein, Silwerstroomstrand, Koeberg and Brackenfell) and one garden growing location in Stellenbosch. Their antifungal activities against Fusarium verticillioides (strains: MRC 826 and MRC 8267) and F. proliferatum (strains: MRC 6908 and MRC 7140) that are aggressive mycotoxigenic phytopathogens were compared using an in vitro microdilution assay. To correlate antifungal activity to chemical profiles, three techniques viz. Gas chromatography-mass spectrometry (GC-MS); Liquid chromatography-mass spectrometry (LC-MS) and 1H Nuclear Magnetic Resonance (NMR) were employed. Principal Component Analysis (PCA) was applied to the NMR data. The partial least squares-discriminant analysis (PLS-DA) was used to integrate LC-MS and NMR data sets. All statistics were performed with the SIMCA-P + 12.0 software. The dichloromethane:methanol (1:1; v/v) extracts of the plant species collected from Stellenbosch demonstrated the strongest inhibition of F. verticillioides and F. proliferatum with minimum inhibitory concentration (MIC) values of 0.031 mg ml-1 and 0.063 mg ml-1 respectively. GC-MS showed four compounds which were unique to the Stellenbosch extracts. By integrating LC-MS and 1H NMR analyses, large chemotype differences leading to samples grouping by site when a multivariate analysis was performed, suggested strong plant-environment interactions as factors influencing metabolite composition. Signals distinguishing the Stellenbosch profile were in the aromatic part of the 1H NMR spectra. This study shows the potential of chemotypes of Salvia africana-lutea in controlling fungal growth and consequently mycotoxin production. Products for use in the agricultural sector may be developed from such chemotypes.

ACS Style

Mpumelelo M Nkomo; David Dr Katerere; Hester Hf Vismer; Thomas T Cruz; Stephane S Balayssac; Myriam M Malet-Martino; Nokwanda Np Makunga. Fusarium inhibition by wild populations of the medicinal plant Salvia africana-lutea L. linked to metabolomic profiling. BMC Complementary and Alternative Medicine 2014, 14, 99 -99.

AMA Style

Mpumelelo M Nkomo, David Dr Katerere, Hester Hf Vismer, Thomas T Cruz, Stephane S Balayssac, Myriam M Malet-Martino, Nokwanda Np Makunga. Fusarium inhibition by wild populations of the medicinal plant Salvia africana-lutea L. linked to metabolomic profiling. BMC Complementary and Alternative Medicine. 2014; 14 (1):99-99.

Chicago/Turabian Style

Mpumelelo M Nkomo; David Dr Katerere; Hester Hf Vismer; Thomas T Cruz; Stephane S Balayssac; Myriam M Malet-Martino; Nokwanda Np Makunga. 2014. "Fusarium inhibition by wild populations of the medicinal plant Salvia africana-lutea L. linked to metabolomic profiling." BMC Complementary and Alternative Medicine 14, no. 1: 99-99.

Journal article
Published: 21 February 2014 in Plant Cell, Tissue and Organ Culture (PCTOC)
Reads 0
Downloads 0

The influence of strigolactones as hormones in plants is not fully characterised even though they are known to affect plant architecture, both above ground and in the roots. Using an in vitro system, the effects of the synthetic auxins 1-naphthalene acetic acid and indole-3-butyric acid (NAA and IBA) and synthetic strigolactones (GR24 and Nijmegen-1) were tested on microplant development of Sutherlandia frutescens, a leguminous medicinal plant native to South Africa. Considerable phytochemical variation in wild populations has led to the proposal of using micropropagation for this species. This will assist with domestication and provide plants with a more predictable chemistry for the phytopharmaceuticals industry. Nodal explants with an axillary bud were grown on Murashige and Skoog (Plant Physiol 15:473–497, 1962) medium [0.8 % (m/v) agar (pH 5.8), 3 % (m/v) sucrose and 0.1 g/L myo-inositol] supplemented with NAA, IBA, GR24 and Nijmegen-1, either singly or in combination. The amino acid profile and secondary metabolite pool was monitored using LC–MS-profiling. Treatment with NAA promoted mass shoot production, whilst a combination of NAA and Nijmegen-1 also positively influenced the accumulation of amino acids, flavonoids (sutherlandins) and terpenoids (sutherlandiosides) that S. frutescens produces. Since these compounds represent the presumed active compounds in this species and the biomarkers used in quality control assessment of S. frutescens tissues harvested for the pharmaceutical industry, this treatment holds promise for the commercial production of Sutherlandia extracts and herbal medications.

ACS Style

Maria C. Grobbelaar; Nokwanda P. Makunga; Marietjie A. Stander; Jens Kossmann; Paul N. Hills. Effect of strigolactones and auxins on growth and metabolite content of Sutherlandia frutescens (L.) R. Br. microplants in vitro. Plant Cell, Tissue and Organ Culture (PCTOC) 2014, 117, 401 -409.

AMA Style

Maria C. Grobbelaar, Nokwanda P. Makunga, Marietjie A. Stander, Jens Kossmann, Paul N. Hills. Effect of strigolactones and auxins on growth and metabolite content of Sutherlandia frutescens (L.) R. Br. microplants in vitro. Plant Cell, Tissue and Organ Culture (PCTOC). 2014; 117 (3):401-409.

Chicago/Turabian Style

Maria C. Grobbelaar; Nokwanda P. Makunga; Marietjie A. Stander; Jens Kossmann; Paul N. Hills. 2014. "Effect of strigolactones and auxins on growth and metabolite content of Sutherlandia frutescens (L.) R. Br. microplants in vitro." Plant Cell, Tissue and Organ Culture (PCTOC) 117, no. 3: 401-409.

Journal article
Published: 01 June 2013 in Journal of Ethnopharmacology
Reads 0
Downloads 0

Plants are often combined in traditional herbal remedies to increase medicinal efficacy, thus this investigation provides some insight into the antimicrobial efficacies of selected combinations. The first aim was to scientifically validate antibacterial efficacy of plant mixtures that are traded within peri-urban centres of Cape Town (Western Cape, South Africa). This was followed by an in-depth evaluation of the most antimicrobially active mixture; Agathosma crenulata, Dodonaea viscosa with Eucalyptus globulus. Methanol and aqueous extracts of six plant mixtures were screened for antibacterial properties against two Gram-negative and two Gram-positive bacteria using the minimum inhibitory microdilution method. Thereafter, chloroform: methanol (1:1; v/v) extracts, essential oils and aqueous extracts of Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus were assayed for antimicrobial activity independently and in various combinations. The fractional inhibitory concentration indices (ƩFIC) were determined for double and triple plant combinations to establish antimicrobial interactions. From the six plant mixtures prepared by herbalists, a methanol extract derived from combining Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus showed the best antibacterial activity. The MIC values of 49μg/ml for Staphylococcus aureus and Bacillus subtilis, and 98μg/ml for Klebsiella pneumoniae and Escherichia coli were recorded. When Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus were mixed in various 1:1 combinations, mostly additive and synergistic interactions were noted. The most noteworthy synergistic (ΣFIC value 0.07) 1:1 combinations were observed for the chloroform: methanol extracts of Agathosma crenulata mixed with Eucalyptus globulus against Klebsiella pneumoniae, Staphylococcus aureus and Bacillus subtilis. When combined in a mixture of three plants (1:1:1), enhanced efficacy was evident against most of the pathogens, for both organic and aqueous extracts. The triple combination against Bacillus subtilis demonstrated the greatest synergy (ΣFIC values of 0.03). The enhanced antimicrobial efficacy and synergistic interactions noted for some of the mixtures, particularly the combination of Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus support the Western Cape Khoi-San traditional medicinal practices of combining plants for enhanced efficacy.

ACS Style

S. Zonyane; Sandy van Vuuren; N.P. Makunga. Antimicrobial interactions of Khoi-San poly-herbal remedies with emphasis on the combination; Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus. Journal of Ethnopharmacology 2013, 148, 144 -151.

AMA Style

S. Zonyane, Sandy van Vuuren, N.P. Makunga. Antimicrobial interactions of Khoi-San poly-herbal remedies with emphasis on the combination; Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus. Journal of Ethnopharmacology. 2013; 148 (1):144-151.

Chicago/Turabian Style

S. Zonyane; Sandy van Vuuren; N.P. Makunga. 2013. "Antimicrobial interactions of Khoi-San poly-herbal remedies with emphasis on the combination; Agathosma crenulata, Dodonaea viscosa and Eucalyptus globulus." Journal of Ethnopharmacology 148, no. 1: 144-151.

Journal article
Published: 30 October 2012 in BMC Complementary and Alternative Medicine
Reads 0
Downloads 0

The original publication is available at http://www.biomedcentral.com/1472-6882/12/200Abstract Background This study evaluated, using in vitro assays, the antibacterial, antioxidant, and tyrosinase-inhibition activities of methanolic extracts from peels of seven commercially grown pomegranate cultivars. Methods Antibacterial activity was tested on Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia) using a microdilution method. Several potential antioxidant activities, including radical-scavenging ability (RSA), ferrous ion chelating (FIC) and ferric ion reducing antioxidant power (FRAP), were evaluated. Tyrosinase enzyme inhibition was investigated against monophenolase (tyrosine) and diphenolase (DOPA), with arbutin and kojic acid as positive controls. Furthermore, phenolic contents including total flavonoid content (TFC), gallotannin content (GTC) and total anthocyanin content (TAC) were determined using colourimetric methods. HPLC-ESI/MSn analysis of phenolic composition of methanolic extracts was also performed. Results Methanolic peel extracts showed strong broad-spectrum activity against Gram-positive and Gram-negative bacteria, with the minimum inhibitory concentrations (MIC) ranging from 0.2 to 0.78 mg/ml. At the highest concentration tested (1000 μg/ml), radical scavenging activities were significantly higher in Arakta (83.54%), Ganesh (83.56%), and Ruby (83.34%) cultivars (P< 0.05). Dose dependent FIC and FRAP activities were exhibited by all the peel extracts. All extracts also exhibited high inhibition (>50%) against monophenolase and diphenolase activities at the highest screening concentration. The most active peel extract was the Bhagwa cultivar against monophenolase and the Arakta cultivar against diphenolase with IC50 values of 3.66 μg/ml and 15.88 μg/ml, respectively. High amounts of phenolic compounds were found in peel extracts with the highest and lowest total phenolic contents of 295.5 (Ganesh) and 179.3 mg/g dry extract (Molla de Elche), respectively. Catechin, epicatechin, ellagic acid and gallic acid were found in all cultivars, of which ellagic acid was the most abundant comprising of more than 50% of total phenolic compounds detected in each cultivar. Conclusions The present study showed that the tested pomegranate peels exhibited strong antibacterial, antioxidant and tyrosinase-inhibition activities. These results suggest that pomegranate fruit peel could be exploited as a potential source of natural antimicrobial and antioxidant agents as well as tyrosinase inhibitors.Publishers' Versio

ACS Style

Olaniyi A. Fawole; Nokwanda P. Makunga; Umezuruike Linus Opara. Antibacterial, antioxidant and tyrosinase-inhibition activities of pomegranate fruit peel methanolic extract. BMC Complementary and Alternative Medicine 2012, 12, 200 -200.

AMA Style

Olaniyi A. Fawole, Nokwanda P. Makunga, Umezuruike Linus Opara. Antibacterial, antioxidant and tyrosinase-inhibition activities of pomegranate fruit peel methanolic extract. BMC Complementary and Alternative Medicine. 2012; 12 (1):200-200.

Chicago/Turabian Style

Olaniyi A. Fawole; Nokwanda P. Makunga; Umezuruike Linus Opara. 2012. "Antibacterial, antioxidant and tyrosinase-inhibition activities of pomegranate fruit peel methanolic extract." BMC Complementary and Alternative Medicine 12, no. 1: 200-200.