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Aflatoxins (AFs) are highly toxic and cancer-causing compounds, predominantly synthesized by the Aspergillus species. AFs biosynthesis is a lengthy process that requires as minimum as 30 genes grouped inside 75 kilobytes (kB) of gene clusters, which are regulated by specific transcription factors, including aflR, aflS, and some general transcription factors. This paper summarizes the status of research on characterizing structural and regulatory genes associated with AF production and their roles in aflatoxigenic fungi, particularly Aspergillus flavus and A. parasiticus, and enhances the current understanding of AFs that adversely affect humans and animals with a great emphasis on toxicity and preventive methods.
Rahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. Aflatoxin Biosynthesis, Genetic Regulation, Toxicity, and Control Strategies: A Review. Journal of Fungi 2021, 7, 606 .
AMA StyleRahim Khan, Farinazleen Ghazali, Nor Mahyudin, Nik Samsudin. Aflatoxin Biosynthesis, Genetic Regulation, Toxicity, and Control Strategies: A Review. Journal of Fungi. 2021; 7 (8):606.
Chicago/Turabian StyleRahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. 2021. "Aflatoxin Biosynthesis, Genetic Regulation, Toxicity, and Control Strategies: A Review." Journal of Fungi 7, no. 8: 606.
High-performance liquid chromatography (HPLC) provides a quick and efficient tool for accurately characterizing aflatoxigenic and non-aflatoxigenic isolates of Aspergillus flavus. This method also provides a quantitative analysis of AFs in Aspergillus flavus. The method’s recovery was assessed by spiking a mixture of AF at different concentrations to the testing medium. The validity of the method was confirmed using aflatoxigenic and non-aflatoxigenic strains of A. flavus. The HPLC system, coupled with a fluorescence detector and post-column photochemical reactor, showed high sensitivity in detecting spiked AFs or AFs produced by A. flavus isolates. Recovery from medium spiked with 10, 20, 60, and 80 ppb of AFs was found to be 73–86% using this approach. For AFB1 and AFB2, the limit of detection was 0.072 and 0.062 ppb, while the limit of quantification was 0.220 and 0.189 ppb, respectively. The AFB1 concentrations ranged from 0.09 to 50.68 ppb, while the AFB2 concentrations ranged between 0.33 and 9.23 ppb. The findings showed that six isolates produced more AFB1 and AFB2 than the acceptable limit of 5 ppb. The incidence of aflatoxigenic isolates of A. flavus in sweet corn and higher concentrations of AFB1 and AFB2 emphasize the need for field trials to explore their real potential for AF production in corn.
Rahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. Chromatographic Analysis of Aflatoxigenic Aspergillus flavus Isolated from Malaysian Sweet Corn. Separations 2021, 8, 98 .
AMA StyleRahim Khan, Farinazleen Ghazali, Nor Mahyudin, Nik Samsudin. Chromatographic Analysis of Aflatoxigenic Aspergillus flavus Isolated from Malaysian Sweet Corn. Separations. 2021; 8 (7):98.
Chicago/Turabian StyleRahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. 2021. "Chromatographic Analysis of Aflatoxigenic Aspergillus flavus Isolated from Malaysian Sweet Corn." Separations 8, no. 7: 98.
Aflatoxins (AFs) are mycotoxins, predominantly produced by Aspergillus flavus, A. parasiticus, A. nomius, and A. pseudotamarii. AFs are carcinogenic compounds causing liver cancer in humans and animals. Physical and biological factors significantly affect AF production during the pre-and post-harvest time. Several methodologies have been developed to control AF contamination, yet; they are usually expensive and unfriendly to the environment. Consequently, interest in using biocontrol agents has increased, as they are convenient, advanced, and friendly to the environment. Using non-aflatoxigenic strains of A. flavus (AF−) as biocontrol agents is the most promising method to control AFs’ contamination in cereal crops. AF− strains cannot produce AFs due to the absence of polyketide synthase genes or genetic mutation. AF− strains competitively exclude the AF+ strains in the field, giving an extra advantage to the stored grains. Several microbiological, molecular, and field-based approaches have been used to select a suitable biocontrol agent. The effectiveness of biocontrol agents in controlling AF contamination could reach up to 99.3%. Optimal inoculum rate and a perfect time of application are critical factors influencing the efficacy of biocontrol agents.
Rahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. Biocontrol of Aflatoxins Using Non-Aflatoxigenic Aspergillus flavus: A Literature Review. Journal of Fungi 2021, 7, 381 .
AMA StyleRahim Khan, Farinazleen Ghazali, Nor Mahyudin, Nik Samsudin. Biocontrol of Aflatoxins Using Non-Aflatoxigenic Aspergillus flavus: A Literature Review. Journal of Fungi. 2021; 7 (5):381.
Chicago/Turabian StyleRahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. 2021. "Biocontrol of Aflatoxins Using Non-Aflatoxigenic Aspergillus flavus: A Literature Review." Journal of Fungi 7, no. 5: 381.
The present work aimed to determine the prevalence of aflatoxigenic Aspergillus section Flavi on different types of dairy goat's feed samples obtained from four dairy goat's farms around the central region of Peninsular Malaysia, and to examine the effects of climatic conditions (temperature, relative humidity) of the dairy goat's farms, and their feeding and storage practices on the fungal prevalence of different types of dairy goat's feed. A total of 60 goat's feed samples were obtained, and their proximate composition and water activity were determined, following which they were cultivated on DRBC and AFPA for total fungal load and Aspergillus section Flavi load determination, respectively. Fungal isolates were identified morphologically, and toxigenicity potentials of Aspergillus section Flavi isolates were determined using CCA. The temperature and relative humidity data of all farms were obtained from the Malaysian Meteorological Department. The total fungal loads (on DRBC) of the goat's feed samples were log 0.767 to 7.071 CFU/g which included the common feed contaminants such as Aspergillus, Fusarium, and Penicillium. The Aspergillus section Flavi loads (on AFPA) were log 0.667 to 3.206 CFU/g. Farm A yielded the highest number of Aspergillus section Flavi isolates as well as the highest number of aflatoxigenic isolates. It was found that climatic conditions and different practices between farms positively influenced the fungal prevalence on goat's feed samples based on the Pearson correlation analysis. The prevalence of mycotoxigenic isolates on goat's feed warrants for urgent intervention to ensure that goats are being fed with nutritionally adequate and safe feed. The presence of aflatoxigenic Aspergillus section Flavi isolates indicates the risk of aflatoxin B1 contamination on the goat's feed, aflatoxicosis development in the goats, and aflatoxin M1 bio-transformation in the goat's milk. This is a potential threat to the flourishing goat's milk industry in Malaysia.
Nur Izzati Azman; Wan Norazihan Wan-Mustapha; Yoh Meng Goh; Hasliza Abu Hassim; Jinap Selamat; Nik Iskandar Putra Samsudin. Climatic conditions and farm practices affected the prevalence of Aspergillus section Flavi on different types of dairy goat's feed. International Journal of Food Microbiology 2021, 347, 109205 .
AMA StyleNur Izzati Azman, Wan Norazihan Wan-Mustapha, Yoh Meng Goh, Hasliza Abu Hassim, Jinap Selamat, Nik Iskandar Putra Samsudin. Climatic conditions and farm practices affected the prevalence of Aspergillus section Flavi on different types of dairy goat's feed. International Journal of Food Microbiology. 2021; 347 ():109205.
Chicago/Turabian StyleNur Izzati Azman; Wan Norazihan Wan-Mustapha; Yoh Meng Goh; Hasliza Abu Hassim; Jinap Selamat; Nik Iskandar Putra Samsudin. 2021. "Climatic conditions and farm practices affected the prevalence of Aspergillus section Flavi on different types of dairy goat's feed." International Journal of Food Microbiology 347, no. : 109205.
Malaysia has begun to locally mass-cultivate grain corn to reduce import dependency for animal feed industries. Since the Malaysian tropical climate constantly exposes grain corn to fungal colonization and mycotoxin production by mycotoxigenic species, it is, therefore, important to investigate the presence of fungal species, especially the mycotoxigenic strains in the Malaysian grain corn agroecosystem. In the present work, corn kernel, tassel, plant debris, and soil were collected from two pioneer grain corn farms (Kampong Dadong, KD; Rhu Tapai, RT), and morphological and molecular identifications were conducted. A total of 131 fungal isolates from 30 fungal species were recovered. Both KD and RT yielded log 4.7–6.7 CFU/g total fungal loads. Fusarium verticillioides was predominant in both farms, followed by the phytopathogenic Lasiodiplodia theobromae and the mycotoxigenic Aspergillus flavus, A. niger, F. incarnatum, and F. proliferatum. Mycotoxin analyses by high-performance liquid chromatography revealed that among 30 mycotoxigenic isolates tested for aflatoxins, deoxynivalenol, fumonisins, HT-2, T-2, ochratoxins A, and zearalenone, approximately 25 of the isolates could produce at least one mycotoxin in vitro. The present work serves as a baseline for more comprehensive research to better predict and control fungal contamination and the subsequent mycotoxin accumulation in Malaysian grain corn agroecosystems.
Siti Yazid; Wan Ng; Jinap Selamat; Siti Ismail; Nik Samsudin. Diversity and Toxigenicity of Mycobiota in Grain Corn: A Case Study at Pioneer Grain Corn Plantations in Terengganu, Malaysia. Agriculture 2021, 11, 237 .
AMA StyleSiti Yazid, Wan Ng, Jinap Selamat, Siti Ismail, Nik Samsudin. Diversity and Toxigenicity of Mycobiota in Grain Corn: A Case Study at Pioneer Grain Corn Plantations in Terengganu, Malaysia. Agriculture. 2021; 11 (3):237.
Chicago/Turabian StyleSiti Yazid; Wan Ng; Jinap Selamat; Siti Ismail; Nik Samsudin. 2021. "Diversity and Toxigenicity of Mycobiota in Grain Corn: A Case Study at Pioneer Grain Corn Plantations in Terengganu, Malaysia." Agriculture 11, no. 3: 237.
The pre-harvest biocontrol approach currently used includes laboratory inoculations using non-aflatoxigenic strains of Aspergillus flavus. This strategy effectively suppresses the indigenous aflatoxigenic strains and reduces aflatoxin accumulation in sweetcorn. The current in vitro study’s main objective is to determine the diametric growth rates of both Aflatoxin (AF)+ and AF− strains and improve the understanding of competitive relationships among these strains in sweetcorn (Zea mays). Sweetcorn kernels inoculated with AF+ strains only, AF− strains only, and co-inoculated with AF+ + AF− strains were investigated for aflatoxin concentrations. The diametric growth results revealed that growth rates of AF− strains at 25 and 30 °C were much greater than AF+ strains, which was in line with previous studies. The in vitro findings showed that the AKR5− and AKL34− biocontrol strains effectively inhibited the colony propagation and subsequent AFB1 contamination (up to 79%) of AF+ strains. On the other hand, the AKR1− and AKL35− were least effective in reducing AFB1 contents only by 58% and 60%, respectively. There was a significant difference (p < 0.05) in the reduction of AFB1 contents achieved by AF− strains of A. flavus. The findings of the present study indicated the reduction in AFB1 with population expressions of AF+ strains by the AF− strains and supports the notion of competitive exclusion through vigorous development and propagation of the non-aflatoxigenic fungi.
Rahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. Co-Inoculation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus flavus to Assess the Efficacy of Non-Aflatoxigenic Strains in Growth Inhibition and Aflatoxin B1 Reduction. Agriculture 2021, 11, 198 .
AMA StyleRahim Khan, Farinazleen Ghazali, Nor Mahyudin, Nik Samsudin. Co-Inoculation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus flavus to Assess the Efficacy of Non-Aflatoxigenic Strains in Growth Inhibition and Aflatoxin B1 Reduction. Agriculture. 2021; 11 (3):198.
Chicago/Turabian StyleRahim Khan; Farinazleen Ghazali; Nor Mahyudin; Nik Samsudin. 2021. "Co-Inoculation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus flavus to Assess the Efficacy of Non-Aflatoxigenic Strains in Growth Inhibition and Aflatoxin B1 Reduction." Agriculture 11, no. 3: 198.
This study aimed to morphologically characterize and determine the aflatoxigenic and non-aflatoxigenic Aspergillus flavus isolates. Forty isolates of A. flavus were obtained from sweet corn kernels and soil samples collected from Kampong Raja, Rose Valley, Kea, and Klebang farms in Malaysia. They were cultured on potato dextrose agar (PDA), dichloran rose-bengal chloramphenicol (DRBC), Aspergillusflavus and Aspergillus parasiticus agar (AFPA), and coconut cream agar (CCA). Macromorphological characteristics were determined by observing the colony color and texture, while the micromorphological characteristics were determined by examining the spore color, size, structure, conidiophore structure, and vesicle shape. The production of aflatoxin was determined by direct visualization of the UV fluorescence of A. flavus colonies on CCA. Aflatoxin was qualitatively detected in 18 (45%) isolates of A. flavus using UV fluorescence screening while the remaining 22 (55%) isolates did not exhibit any aflatoxin production. The highest incidence of A. flavus (30%) and aflatoxin production (15%) was recorded in samples from Kampong Raja. On the other hand, isolates from Rose Valley (17%) and Kea (12%) were non-aflatoxigenic. Klebang recorded a 25% incidence of A. flavus in which 15% were aflatoxigenic while 10% were non-aflatoxigenic. The occurrence of aflatoxin-producing A. flavus emphasizes the need for the measure to eradicate their presence in food crops. A biological control treatment utilizing the non-aflatoxigenic strains to compete with the aflatoxigenic ones is underway. Validation of aflatoxin production through high performance liquid chromatography is also ongoing.
Rahim Khan; Farinazleen Mohamad Ghazali; Nor Mahyudin; Nik Samsudin. Morphological Characterization and Determination of Aflatoxigenic and Non-Aflatoxigenic Aspergillus flavus Isolated from Sweet Corn Kernels and Soil in Malaysia. Agriculture 2020, 10, 450 .
AMA StyleRahim Khan, Farinazleen Mohamad Ghazali, Nor Mahyudin, Nik Samsudin. Morphological Characterization and Determination of Aflatoxigenic and Non-Aflatoxigenic Aspergillus flavus Isolated from Sweet Corn Kernels and Soil in Malaysia. Agriculture. 2020; 10 (10):450.
Chicago/Turabian StyleRahim Khan; Farinazleen Mohamad Ghazali; Nor Mahyudin; Nik Samsudin. 2020. "Morphological Characterization and Determination of Aflatoxigenic and Non-Aflatoxigenic Aspergillus flavus Isolated from Sweet Corn Kernels and Soil in Malaysia." Agriculture 10, no. 10: 450.
BACKGROUND Corn, a main feed ingredient in the livestock industry, is one of the most susceptible crops to fungal infection and aflatoxin contamination. Livestock feeding on aflatoxin‐contaminated feed have been shown to cause feed refusal, and decreased growth rate, milk production and feed efficiency. In poultry, aflatoxin poisoning causes weight loss, poor feed efficiency, and reduced egg production and egg weight. Therefore, the present work was conducted to determine the prevalence of mycotoxigenic fungi and the occurrence of AF contamination along the integrated corn‐based poultry feed supply chain in Malaysia. A total of 51 samples were collected from different points along the feed supply chain from integrated poultry feed companies. The samples were subjected to mycological analyses (fungal isolation, enumeration, identification), and aflatoxins were quantified by high performance liquid chromatography equipped with fluorescence detector (HPLC‐FLD). RESULTS Samples collected from Sampling Point 1 (company A) and Sampling Point 9 (company B) yielded the highest total fungal load (> log 4 CFU g−1). The prevalent fungal genera isolated were Aspergillus, Fusarium, and Penicillium spp. Aflatoxin B1 was detected in 8.3% of corn samples, and 7.4% of corn‐based poultry feed samples along the feed supply chain, whereas aflatoxins B2, G1, and G2 were not detected. CONCLUSION The incidence of mycotoxigenic fungi along the integrated poultry feed supply chain warrant the need for continuous monitoring of mycotoxin contamination to reduce the exposure risk of mycotoxin intake in poultry. This article is protected by copyright. All rights reserved.
Norafidah Nasaruddin; Selamat Jinap; Nik Iskandar Putra Samsudin; Nitty Hirawaty Kamarulzaman; Maimunah Sanny. Prevalence of mycotoxigenic fungi and assessment of aflatoxin contamination: a multiple case study along the integrated corn‐based poultry feed supply chain in Malaysia. Journal of the Science of Food and Agriculture 2020, 101, 1812 -1821.
AMA StyleNorafidah Nasaruddin, Selamat Jinap, Nik Iskandar Putra Samsudin, Nitty Hirawaty Kamarulzaman, Maimunah Sanny. Prevalence of mycotoxigenic fungi and assessment of aflatoxin contamination: a multiple case study along the integrated corn‐based poultry feed supply chain in Malaysia. Journal of the Science of Food and Agriculture. 2020; 101 (5):1812-1821.
Chicago/Turabian StyleNorafidah Nasaruddin; Selamat Jinap; Nik Iskandar Putra Samsudin; Nitty Hirawaty Kamarulzaman; Maimunah Sanny. 2020. "Prevalence of mycotoxigenic fungi and assessment of aflatoxin contamination: a multiple case study along the integrated corn‐based poultry feed supply chain in Malaysia." Journal of the Science of Food and Agriculture 101, no. 5: 1812-1821.
Climate change is primarily manifested by elevated temperature and carbon dioxide (CO2) levels and is projected to provide suitable cultivation grounds for pests and pathogens in the otherwise unsuitable regions. The impacts of climate change have been predicted in many parts of the world, which could threaten global food safety and food security. The aim of the present work was therefore to examine the interacting effects of water activity (aw) (0.92, 0.95, 0.98 aw), CO2 (400, 800, 1200 ppm) and temperature (30, 35 °C and 30, 33 °C for Fusarium verticillioides and F. graminearum, respectively) on fungal growth and mycotoxin production of acclimatised isolates of F. verticillioides and F. graminearum isolated from maize. To determine fungal growth, the colony diameters were measured on days 1, 3, 5, and 7. The mycotoxins produced were quantified using a quadrupole-time-of-flight mass spectrometer (QTOF-MS) combined with ultra-high-performance liquid chromatography (UHPLC) system. For F. verticillioides, the optimum conditions for growth of fumonisin B1 (FB1), and fumonisin B2 (FB2) were 30 °C + 0.98 aw + 400 ppm CO2. These conditions were also optimum for F. graminearum growth, and zearalenone (ZEA) and deoxynivalenol (DON) production. Since 30 °C and 400 ppm CO2 were the baseline treatments, it was hence concluded that the elevated temperature and CO2 levels tested did not seem to significantly impact fungal growth and mycotoxin production of acclimatised Fusarium isolates. To the best of our knowledge thus far, the present work described for the first time the effects of simulated climate change conditions on fungal growth and mycotoxin production of acclimatised isolates of F. verticillioides and F. graminearum.
Ladi Peter Mshelia; Jinap Selamat; Nik Iskandar Putra Samsudin; Mohd Y. Rafii; Noor-Azira Abdul Mutalib; Noordiana Nordin; Franz Berthiller. Effect of Temperature, Water Activity and Carbon Dioxide on Fungal Growth and Mycotoxin Production of Acclimatised Isolates of Fusarium verticillioides and F. graminearum. Toxins 2020, 12, 478 .
AMA StyleLadi Peter Mshelia, Jinap Selamat, Nik Iskandar Putra Samsudin, Mohd Y. Rafii, Noor-Azira Abdul Mutalib, Noordiana Nordin, Franz Berthiller. Effect of Temperature, Water Activity and Carbon Dioxide on Fungal Growth and Mycotoxin Production of Acclimatised Isolates of Fusarium verticillioides and F. graminearum. Toxins. 2020; 12 (8):478.
Chicago/Turabian StyleLadi Peter Mshelia; Jinap Selamat; Nik Iskandar Putra Samsudin; Mohd Y. Rafii; Noor-Azira Abdul Mutalib; Noordiana Nordin; Franz Berthiller. 2020. "Effect of Temperature, Water Activity and Carbon Dioxide on Fungal Growth and Mycotoxin Production of Acclimatised Isolates of Fusarium verticillioides and F. graminearum." Toxins 12, no. 8: 478.
Mycotoxins are an important class of pollutants that are toxic and hazardous to animal and human health. Consequently, various methods have been explored to abate their effects, among which adsorbent has found prominent application. Liquid chromatography tandem mass spectrometry (LC–MS/MS) has recently been applied for the concurrent evaluation of multiple mycotoxins. This study investigated the optimization of the simultaneous removal of mycotoxins in palm kernel cake (PKC) using chitosan. The removal of 11 mycotoxins such as aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), zearalenone (ZEA), fumonisins (FB1 and FB2) and trichothecenes (deoxynivalenol (DON), HT-2 and T-2 toxin) from palm kernel cake (PKC) was studied. The effects of operating parameters such as pH (3–6), temperature (30–50 °C) and time (4–8 h) on the removal of the mycotoxins were investigated using response surface methodology (RSM). Response surface models obtained with R2 values ranging from 0.89–0.98 fitted well with the experimental data, except for the trichothecenes. The optimum point was obtained at pH 4, 8 h and 35 °C. The maximum removal achieved with chitosan for AFB1, AFB2, AFG1, AFG2, OTA, ZEA, FB1 and FB2 under the optimized conditions were 94.35, 45.90, 82.11, 84.29, 90.03, 51.30, 90.53 and 90.18%, respectively.
Atena Abbasi Pirouz; Jinap Selamat; Shahzad Zafar Iqbal; Nik Iskandar Putra Samsudin. Efficient and Simultaneous Chitosan-Mediated Removal of 11 Mycotoxins from Palm Kernel Cake. Toxins 2020, 12, 115 .
AMA StyleAtena Abbasi Pirouz, Jinap Selamat, Shahzad Zafar Iqbal, Nik Iskandar Putra Samsudin. Efficient and Simultaneous Chitosan-Mediated Removal of 11 Mycotoxins from Palm Kernel Cake. Toxins. 2020; 12 (2):115.
Chicago/Turabian StyleAtena Abbasi Pirouz; Jinap Selamat; Shahzad Zafar Iqbal; Nik Iskandar Putra Samsudin. 2020. "Efficient and Simultaneous Chitosan-Mediated Removal of 11 Mycotoxins from Palm Kernel Cake." Toxins 12, no. 2: 115.
In this review, we present the current information on development and applications of biological control against phytopathogenic organisms as well as mycotoxigenic fungi in Malaysia as part of the integrated pest management (IPM) programs in a collective effort to achieve food security. Although the biological control of phytopathogenic organisms of economically important crops is well established and widely practiced in Malaysia with considerable success, the same cannot be said for mycotoxigenic fungi. This is surprising because the year round hot and humid Malaysian tropical climate is very conducive for the colonization of mycotoxigenic fungi and the potential contamination with mycotoxins. This suggests that less focus has been made on the control of mycotoxigenic species in the genera Aspergillus, Fusarium, and Penicillium in Malaysia, despite the food security and health implications of exposure to the mycotoxins produced by these species. At present, there is limited research in Malaysia related to biological control of the key mycotoxins, especially aflatoxins, Fusarium‐related mycotoxins, and ochratoxin A, in key food and feed chains. The expected threats of climate change, its impacts on both plant physiology and the proliferation of mycotoxigenic fungi, and the contamination of food and feed commodities with mycotoxins, including the discovery of masked mycotoxins, will pose significant new global challenges that will impact on mycotoxin management strategies in food and feed crops worldwide. Future research, especially in Malaysia, should urgently focus on these challenges to develop IPM strategies that include biological control for minimizing mycotoxins in economically important food and feed chains for the benefit of ensuring food safety and food security under climate change scenarios.
Siti Nur Ezzati Yazid; Selamat Jinap; Siti Izera Ismail; Naresh Magan; Nik Iskandar Putra Samsudin. Phytopathogenic organisms and mycotoxigenic fungi: Why do we control one and neglect the other? A biological control perspective in Malaysia. Comprehensive Reviews in Food Science and Food Safety 2020, 19, 643 -669.
AMA StyleSiti Nur Ezzati Yazid, Selamat Jinap, Siti Izera Ismail, Naresh Magan, Nik Iskandar Putra Samsudin. Phytopathogenic organisms and mycotoxigenic fungi: Why do we control one and neglect the other? A biological control perspective in Malaysia. Comprehensive Reviews in Food Science and Food Safety. 2020; 19 (2):643-669.
Chicago/Turabian StyleSiti Nur Ezzati Yazid; Selamat Jinap; Siti Izera Ismail; Naresh Magan; Nik Iskandar Putra Samsudin. 2020. "Phytopathogenic organisms and mycotoxigenic fungi: Why do we control one and neglect the other? A biological control perspective in Malaysia." Comprehensive Reviews in Food Science and Food Safety 19, no. 2: 643-669.
Peanuts are widely consumed in many local dishes in southeast Asian countries, especially in Malaysia which is one of the major peanut-importing countries in this region. Therefore, Aspergillus spp. and aflatoxin contamination in peanuts during storage are becoming major concerns due to the tropical weather in this region that favours the growth of aflatoxigenic fungi. The present study thus aimed to molecularly identify and characterise the Aspergillus section Flavi isolated from imported peanuts in Malaysia. The internal transcribed spacer (ITS) and β-tubulin sequences were used to confirm the species and determine the phylogenetic relationship among the isolates, while aflatoxin biosynthesis genes (aflR, aflP (omtA), aflD (nor-1), aflM (ver-1), and pksA) were targeted in a multiplex PCR to determine the toxigenic potential. A total of 76 and one isolates were confirmed as A. flavus and A. tamarii, respectively. The Maximum Likelihood (ML) phylogenetic tree resolved the species into two different clades in which all A. flavus (both aflatoxigenic and non-aflatoxigenic) were grouped in the same clade and A. tamarii was grouped in a different clade. The aflatoxin biosynthesis genes were detected in all aflatoxigenic A. flavus while the non-aflatoxigenic A. flavus failed to amplify at least one of the genes. The results indicated that both aflatoxigenic and non-aflatoxigenic A. flavus could survive in imported peanuts and, thus, appropriate storage conditions preferably with low temperature should be considered to avoid the re-emergence of aflatoxigenic A. flavus and the subsequent aflatoxin production in peanuts during storage.
Mahror Norlia; Selamat Jinap; Mahmud Ab Rashid Nor-Khaizura; Son Radu; Cheow Keat Chin; Nik Iskandar Putra Samsudin; Abdul Halim Farawahida. Molecular Characterisation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus Section Flavi Isolated from Imported Peanuts along the Supply Chain in Malaysia. Toxins 2019, 11, 501 .
AMA StyleMahror Norlia, Selamat Jinap, Mahmud Ab Rashid Nor-Khaizura, Son Radu, Cheow Keat Chin, Nik Iskandar Putra Samsudin, Abdul Halim Farawahida. Molecular Characterisation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus Section Flavi Isolated from Imported Peanuts along the Supply Chain in Malaysia. Toxins. 2019; 11 (9):501.
Chicago/Turabian StyleMahror Norlia; Selamat Jinap; Mahmud Ab Rashid Nor-Khaizura; Son Radu; Cheow Keat Chin; Nik Iskandar Putra Samsudin; Abdul Halim Farawahida. 2019. "Molecular Characterisation of Aflatoxigenic and Non-Aflatoxigenic Strains of Aspergillus Section Flavi Isolated from Imported Peanuts along the Supply Chain in Malaysia." Toxins 11, no. 9: 501.
In studying the ecophysiology of fungal phytopathogens, several stages are involved (in vitro, greenhouse, in planta). Most in vitro studies extensively utilise the general growth media such as Potato Dextrose Agar and Malt Extract Agar. Although the crop components in these media serve as excellent carbon sources and yield luxuriant growth, they are not naturally contaminated with Aspergillus flavus and thus might result in under- or overestimation of its actual toxigenic potentials. Empirical data on the formulation of semi-synthetic growth medium mimicking the natural crop commonly contaminated by A. flavus for the ecophysiological studies in vitro are scarce. The present work was aimed at investigating the ecophysiology of A. flavus on commercial growth media (PDA, MEA); formulating maize- and peanut-based semi-synthetic growth media using two methods of raw material preparation (milling, hot water extraction) at different concentrations (1, 3, 5, 7, 9% w/v), and comparing the ecophysiological parameters between commercial and formulated growth media. Growth rates were obtained by computing the hyphal expansion data into y = mx + c equation. AFB was quantified using high performance liquid chromatography with fluorescence detector. Formulated media were found to yield significantly higher growth rates when compared to commercial media. However, commercial media yielded significantly higher AFB when compared to all formulated media. Between the two formulations, milling yielded significantly higher growth rates and AFB when compared to hot water extraction. Although in vitro data cannot directly extrapolate in planta performance, results obtained in the present work can be used to gauge the actual toxigenic potential of A. flavus in maize and peanut agro-ecosystems.
Siti Nur Ezzati Yazid; Hemashangari Thanggavelu; Norlia Mahror; Jinap Selamat; Nik Iskandar Putra Samsudin. Formulation of maize- and peanut-based semi-synthetic growth media for the ecophysiological studies of aflatoxigenic Aspergillus flavus in maize and peanut agro-ecosystems. International Journal of Food Microbiology 2018, 282, 57 -65.
AMA StyleSiti Nur Ezzati Yazid, Hemashangari Thanggavelu, Norlia Mahror, Jinap Selamat, Nik Iskandar Putra Samsudin. Formulation of maize- and peanut-based semi-synthetic growth media for the ecophysiological studies of aflatoxigenic Aspergillus flavus in maize and peanut agro-ecosystems. International Journal of Food Microbiology. 2018; 282 ():57-65.
Chicago/Turabian StyleSiti Nur Ezzati Yazid; Hemashangari Thanggavelu; Norlia Mahror; Jinap Selamat; Nik Iskandar Putra Samsudin. 2018. "Formulation of maize- and peanut-based semi-synthetic growth media for the ecophysiological studies of aflatoxigenic Aspergillus flavus in maize and peanut agro-ecosystems." International Journal of Food Microbiology 282, no. : 57-65.
This paper discusses the relationship between biocontrol agents (BCAs) and mycotoxigenic fungi and mycotoxin control. In most cases BCAs are examined for control of growth of fungal pathogens and disease symptoms. However, for mycotoxin control the approach and focus needs to be different. The mechanism of action and the inoculum dose necessary for control of toxin production by Aspegillus, Penicillium and Fusarium species may be different from that for traditional fungal plant pathogens. The mechanisms of action, the relative inoculum potential and the impact that interacting environmental conditions have on control of key components of the life cycle of mycotoxigenic fungi are considered. The practical aspects of production and formulation hurdles are discussed and potential future approaches and strategies which may need to be considered for more effective biocontrol of mycotoxigenic fungi and mycotoxins are presented.
Angel Medina; Sejakhosi Mohale; Nik Iskandar Putra Samsudin; Alicia Rodriguez-Sixtos; Alicia Rodriguez; Naresh Magan. Biocontrol of mycotoxins: dynamics and mechanisms of action. Current Opinion in Food Science 2017, 17, 41 -48.
AMA StyleAngel Medina, Sejakhosi Mohale, Nik Iskandar Putra Samsudin, Alicia Rodriguez-Sixtos, Alicia Rodriguez, Naresh Magan. Biocontrol of mycotoxins: dynamics and mechanisms of action. Current Opinion in Food Science. 2017; 17 ():41-48.
Chicago/Turabian StyleAngel Medina; Sejakhosi Mohale; Nik Iskandar Putra Samsudin; Alicia Rodriguez-Sixtos; Alicia Rodriguez; Naresh Magan. 2017. "Biocontrol of mycotoxins: dynamics and mechanisms of action." Current Opinion in Food Science 17, no. : 41-48.
Among the many roles played by small and medium enterprises (SMEs) in the food industry is the production of heritage foods such as peanut sauce. Unfortunately, the safety of peanut sauce is not always assured as the processing line is not controlled. Peanut sauce is usually made of peanuts and chilli, and these commodities are normally contaminated with Aspergillus spp. and aflatoxins (AFs). Hence, the objective of this study was to evaluate the practices related to reduction of AF hazard and the effect of interventions in peanut sauce processing. Peanut samples were collected from each step of peanut sauce processing from a small peanut sauce company according to four designs: (1) control; (2) oil-less frying of chilli powder; (3) addition of retort processing; and (4) combination of oil-less frying of chilli powder and retort processing. Oil-less frying of chilli powder (Design 2) reduced total AFs by 33–41%, retort processing (Design 3) reduced total AFs by 49%, while combination of these two thermal processes (Design 4) significantly reduced total AFs, by 57%. The present work demonstrated that Design 4 yielded the highest reduction of total AFs and is therefore recommended to be employed by SME companies.
A. H. Farawahida; S. Jinap; M. A. R. Nor-Khaizura; Nik Iskandar Putra Samsudin. Reduction of Aspergillus spp. and aflatoxins in peanut sauce processing by oil-less frying of chilli powder and retort processing. Food Additives & Contaminants: Part A 2017, 34, 2242 -2250.
AMA StyleA. H. Farawahida, S. Jinap, M. A. R. Nor-Khaizura, Nik Iskandar Putra Samsudin. Reduction of Aspergillus spp. and aflatoxins in peanut sauce processing by oil-less frying of chilli powder and retort processing. Food Additives & Contaminants: Part A. 2017; 34 (12):2242-2250.
Chicago/Turabian StyleA. H. Farawahida; S. Jinap; M. A. R. Nor-Khaizura; Nik Iskandar Putra Samsudin. 2017. "Reduction of Aspergillus spp. and aflatoxins in peanut sauce processing by oil-less frying of chilli powder and retort processing." Food Additives & Contaminants: Part A 34, no. 12: 2242-2250.
This study was carried out to examine the efficacy of two biocontrol agents (Clonostachys rosea 016, BCA1; Gram-negative bacterium, BCA5) for control of FUM1 gene expression and fumonisin B (FB) production by F. verticillioides FV1 on maize cobs of different ripening stages: R, Milk (0.985 a); R, Dough (0.976 a); R, Dent (0.958 a). Initially, temporal studies on FUM1 gene expression and FB production were performed on maize kernels for up to 14days. This revealed that day 10 was optimum for both parameters, and was used in the biocontrol studies. Maize cobs were inoculated with 50:50 mixtures of the pathogen:antagonist inoculum and incubated in environmental chambers to maintain the natural a conditions for ten days at 25 and 30°C. The growth rates of F. verticillioides FV1, the relative expression of the FUM1 gene and FB production were quantified. It was found that, a×temp had significant impacts on growth, FUM1 gene expression and FB production by F. verticillioides FV1 on maize cobs of different maturities. The fungal antagonist (BCA1) significantly reduced FB contamination on maize cobs by >70% at 25°C, and almost 60% at 30°C regardless of maize ripening stage. For the bacterial antagonist (BCA5) however, FB levels on maize cobs were significantly decreased only in some treatments. These results suggest that efficacy of antagonists to control mycotoxin production in ripening maize cobs needs to take account of the ecophysiology of the pathogen and the antagonists, as well as the physiological status of the maize during silking to ensure effective control.
Nik Iskandar Putra Samsudin; Alicia Rodriguez; Angel Medina; Naresh Magan. Efficacy of fungal and bacterial antagonists for controlling growth, FUM1 gene expression and fumonisin B 1 production by Fusarium verticillioides on maize cobs of different ripening stages. International Journal of Food Microbiology 2017, 246, 72 -79.
AMA StyleNik Iskandar Putra Samsudin, Alicia Rodriguez, Angel Medina, Naresh Magan. Efficacy of fungal and bacterial antagonists for controlling growth, FUM1 gene expression and fumonisin B 1 production by Fusarium verticillioides on maize cobs of different ripening stages. International Journal of Food Microbiology. 2017; 246 ():72-79.
Chicago/Turabian StyleNik Iskandar Putra Samsudin; Alicia Rodriguez; Angel Medina; Naresh Magan. 2017. "Efficacy of fungal and bacterial antagonists for controlling growth, FUM1 gene expression and fumonisin B 1 production by Fusarium verticillioides on maize cobs of different ripening stages." International Journal of Food Microbiology 246, no. : 72-79.
Recently, it was shown that a strain of the fungal antagonist Clonostachys rosea 016 was able to inhibit fumonisin B1 mycotoxin production by Fusarium verticillioides FV1 when using different ratios of spores of each species in vitro. The objectives of the present work were therefore to: (a) compare the nutritional utilisation patterns and rates of uptake of key C-sources in maize by the antagonist C. rosea 016 and that by the pathogen F. verticillioides FV1; (b) examine their Niche Overlap Indices (NOI) under different interacting environmental conditions; and (c) evaluate whether the rate of utilisation of key maize C-sources influenced the competitiveness of either species using the Bioscreen®. It was found that water potential (Ψ) × temperature interactions had significant impacts on C-source utilisation patterns by C. rosea 016 and the pathogen. The NOIs, based on the utilisation of the C-sources by each strain divided by those utilised in common, showed that the antagonist and the pathogen occupied similar niches at −0.70 MPa Ψ+30 °C and −2.8 MPa Ψ+25 °C. Under the other conditions tested, they appeared to occupy separate niches suggesting niche exclusion. Temporal C-source utilisation patterns were then compared under different Ψ × temperature treatments. This showed that the dominant maize-based C-sources utilised by the pathogen and the antagonist were different. The pathogen F. verticillioides FV1 utilised carbohydrates rapidly followed by amino acids and then one fatty acid, palmitic acid. The antagonist C. rosea 016 utilised both carbohydrates and amino acids at a similar rate but more slowly than the pathogen. There were also differences in the utilisation of some individual amino acids and carbohydrates which might explain the occupation of different niches under some interacting environmental conditions. These findings are discussed in the context of why some competitors are able to inhibit mycotoxin production while others cannot
Nik Iskandar Putra Samsudin; Angel Medina; Naresh Magan. Relationship between environmental conditions, carbon utilisation patterns and Niche Overlap Indices of the mycotoxigenic species Fusarium verticillioides and the biocontrol agent Clonostachys rosea. Fungal Ecology 2016, 24, 44 -52.
AMA StyleNik Iskandar Putra Samsudin, Angel Medina, Naresh Magan. Relationship between environmental conditions, carbon utilisation patterns and Niche Overlap Indices of the mycotoxigenic species Fusarium verticillioides and the biocontrol agent Clonostachys rosea. Fungal Ecology. 2016; 24 ():44-52.
Chicago/Turabian StyleNik Iskandar Putra Samsudin; Angel Medina; Naresh Magan. 2016. "Relationship between environmental conditions, carbon utilisation patterns and Niche Overlap Indices of the mycotoxigenic species Fusarium verticillioides and the biocontrol agent Clonostachys rosea." Fungal Ecology 24, no. : 44-52.
A mycotoxigenic strain of Fusarium verticillioides previously isolated from Malaysian maize kernels and identified morphologically and molecularly was used in the present work. The objectives were (1) to screen the competitiveness of three potential antagonists isolated from Malaysian maize and three other known candidates for control of growth of F. verticillioides in vitro based on interaction scores, growth rates and hyphal area of F. verticillioides, and (2) to examine the best candidates using different spore/cell ratios on milled maize agar at different water activity conditions on relative control of fumonisin B1 (FB1). Three fungi and three bacteria (BCAs 1-6) were examined for antagonistic effects against F. verticillioides in dual-culture assays. These showed that all fungal candidates intermingled with F. verticillioides while all bacterial candidates inhibited F. verticillioides on contact or at a distance, which in turn decreased the growth rates and hyphal area of F. verticillioides significantly. Although BCA1 (Clonostachys rosea 016) did not inhibit growth or hyphal area of F. verticillioides, it was included in FB1 inhibition studies with other bacterial candidates (BCA4, Streptomyces sp. AS1; BCA5, Gram-negative rod; BCA6, Enterobacter hormaechei) because of its established mycoparasitism. The FB1 inhibition studies were conducted on milled maize agar with different spore/cell ratios of pathogen:antagonist mixtures at 0.95/0.98 water activity (aw) and 25 °C for 14 days. FB1 biosynthesis for all treatments was significantly higher at 0.95 than 0.98 aw. Of the four antagonists tested, the best was BCA1 which inhibited FB1 biosynthesis by 73 and 100% at 0.95 and 0.98 aw, respectively. BCA5 was the next best, resulting in 38 and 78% FB1 inhibition at 0.95 and 0.98 aw, respectively. The pathogen:antagonist ratios for BCA1 and BCA5 showed best results at 50:50 and 25:75. These results were discussed in context of using biocontrol agents to minimise fumonisins in maize.
Nik Iskandar Putra Samsudin; N. Magan. Efficacy of potential biocontrol agents for control of Fusarium verticillioides and fumonisin B1 under different environmental conditions. World Mycotoxin Journal 2016, 9, 205 -213.
AMA StyleNik Iskandar Putra Samsudin, N. Magan. Efficacy of potential biocontrol agents for control of Fusarium verticillioides and fumonisin B1 under different environmental conditions. World Mycotoxin Journal. 2016; 9 (2):205-213.
Chicago/Turabian StyleNik Iskandar Putra Samsudin; N. Magan. 2016. "Efficacy of potential biocontrol agents for control of Fusarium verticillioides and fumonisin B1 under different environmental conditions." World Mycotoxin Journal 9, no. 2: 205-213.
Red rice is a fermented product of Monascus spp. It is widely consumed by Malaysian Chinese who believe in its pharmacological properties. The traditional method of red rice preparation disregards safety regulation and renders red rice susceptible to fungal infestation and mycotoxin contamination. A preliminary study was undertaken aiming to determine the occurrence of mycotoxigenic fungi and mycotoxins contamination on red rice at consumer level in Selangor, Malaysia. Fifty red rice samples were obtained and subjected to fungal isolation, enumeration, and identification. Citrinin, aflatoxin, and ochratoxin-A were quantitated by ELISA based on the presence of predominant causal fungi. Fungal loads of 1.4 × 104 to 2.1 × 106 CFU/g exceeded Malaysian limits. Monascus spp. as starter fungi were present in 50 samples (100 %), followed by Penicillium chrysogenum (62 %), Aspergillus niger (54 %), and Aspergillus flavus (44 %). Citrinin was present in 100 % samples (0.23–20.65 mg/kg), aflatoxin in 92 % samples (0.61–77.33 μg/kg) and Ochratoxin-A in 100 % samples (0.23–2.48 μg/kg); 100 % citrinin and 76.09 % aflatoxin exceeded Malaysian limits. The presence of mycotoxigenic fungi served as an indicator of mycotoxins contamination and might imply improper production, handling, transportation, and storage of red rice. Further confirmatory analysis (e.g., HPLC) is required to verify the mycotoxins level in red rice samples and to validate the safety status of red rice.
Nik Iskandar Putra Samsudin; Noorlidah Abdullah. A preliminary survey on the occurrence of mycotoxigenic fungi and mycotoxins contaminating red rice at consumer level in Selangor, Malaysia. Mycotoxin Research 2012, 29, 89 -96.
AMA StyleNik Iskandar Putra Samsudin, Noorlidah Abdullah. A preliminary survey on the occurrence of mycotoxigenic fungi and mycotoxins contaminating red rice at consumer level in Selangor, Malaysia. Mycotoxin Research. 2012; 29 (2):89-96.
Chicago/Turabian StyleNik Iskandar Putra Samsudin; Noorlidah Abdullah. 2012. "A preliminary survey on the occurrence of mycotoxigenic fungi and mycotoxins contaminating red rice at consumer level in Selangor, Malaysia." Mycotoxin Research 29, no. 2: 89-96.