Cannabis sativa is known among many cultures for its medicinal potential. Its complexity contributes to the historical application of various parts of the plant in ethno-medicines and pharmacotherapy. C. sativa has been used for the treatment of rheumatism, epilepsy, asthma, skin burns, pain, the management of sexually transmitted diseases, difficulties during child labor, postpartum hemorrhage, and gastrointestinal activity. However, the use of C. sativa is still limited, and it is illegal in most countries. Thus, this review aims to highlight the biological potential of the plant parts, as well as the techniques for the extraction, isolation, and characterization of C. sativa compounds. The plant produces a unique class of terpenophenolic compounds, called cannabinoids, as well as non-cannabinoid compounds. The exhaustive profiling of bioactive compounds and the chemical characterization and analysis of C. sativa compounds, which modern research has not yet fully achieved, is needed for the consistency, standardization, and the justified application of Cannabis sativa products for therapeutic purposes. Studies on the clinical relevance and applications of cannabinoids and non-cannabinoid phenols in the prevention and treatment of life-threatening diseases is indeed significant. Furthermore, psychoactive cannabinoids, when chemically standardized and administered under medical supervision, can be the legal answer to the use of C. sativa.

The medicinal potential and volatile composition of different parts of three cultivars of grapefruit (Citrus paradisi) were evaluated for their toxicity and anti-inflammatory activities. Fresh leaf and fruit peel were separately isolated by hydrodistillation for 4 h. The essential oils were subjected to GC/GC-MS analysis for chemical profile. Toxicity of the essential oils in mice were evaluated using Lorke’s method, while an anti-inflammatory assay was performed in a rat model using egg albumin-induced oedema. The oils obtained were light yellow in colour, and odour varied from strong citrus smell to mild. Percentage yield of fresh peel oil (0.34–0.57%) was greater than the fresh leaf oil yield (0.21–0.34%). D-limonene (86.70–89.90%) was the major compound identified in the leaf oil, while β-phellandrene (90.00–91.01%) dominated the peel oil. At a dosage level of 5000 mg/kg, none of the oils showed mortality in mice. An anti-inflammatory bioassay revealed that all the oils caused a significant (p < 0.05–0.01) reduction in oedema size when compared to the negative control group throughout the 5 h post induction assessment period. The study reveals that the oils are non-toxic and demonstrate significant anti-inflammatory activity. Our findings suggest that the leaf and peel oils obtained from waste parts of grapefruit plants can be useful as flavouring agents, as well as anti-inflammatory agents.

Pelargonium species are native to South Africa, and they have a long history in medicinal use. This study aimed to extract essential oils from different parts of P. peltatum, determine the chemical composition of the essential oils, and assess the essential oils’ biological potential as analgesic and anti-inflammatory agents. The essential oils were obtained by hydro-distilling different parts of P. peltatum, and the essential profile was determined by GC-FID and GC-MS. The analgesic activity of the essential oil was determined by using a tail immersion in hot water method in rats, whereas the anti-inflammatory activity of the essential oils was assessed according to right hind paw oedema induced by egg albumin; the three doses selected for each experiment were 100, 200, and 400 mg/kg. According to the GC-FID and GC-MS analysis, camphene (3.6–33.4%), α-terpineol (4.8–19.1%), α-thujone (1.5–15.6%), piperitone (0.9–12.2%), linalool (1.6–11.7%), myrcene (5.2–10.7%), germacrene D (3.7–10.4%), β-caryophyllene (1.2–9.5%), β-cadinene (3.4–6.7%), and β-bourbonene (4.2–6.2%) were some of the major compounds identified in the oil. P. peltatum essential oils demonstrated analgesic activity by increasing pain latency in hot water; furthermore, in an inflammation test, the essential oil reduced the egg-albumin-induced paw oedema in both the first and second phases. Therefore, the current findings suggest that P. peltatum essential oils have analgesic and anti-inflammatory properties.

A decoction of Dalbergiella welwitschii leaves has been used ethnomedicinally for the treatment of mental illness and inflammatory diseases amongst other diseases. In this study, the leaf methanol extract of D. welwitschii and its partition fractions: n-hexane, ethyl acetate and aqueous, were tested and evaluated for their polyphenolic contents, free radical scavenging and cholinesterase inhibitory activities. The total phenolic (TPC), flavonoid (TFC) and proanthocyanidin (TPA) contents were determined using standard colorimetric methods. The anti-radical activity of the extracts against the 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric ion and nitric oxide (NO) radicals as well as their effects on lipid peroxidation were monitored spectrophotometrically. The cholinesterase enzyme (AChE and BuChE) inhibitions by the extracts were determined by a modified method of Ellman. The result showed a concentration-dependent increase in inhibition of the free radicals and the cholinesterase enzymes, except for that of lipid peroxidation. The ethyl acetate (EtOAc) fraction exhibited the highest polyphenolic contents among the fractions, with a TPC of 1.08 mgGAE/g, TFC of 0.38 mgQuE/g and TPA of 0.21 mgGAE/g. It also demonstrated the highest free radical scavenging activities with 72.63% and 65.43% inhibitions of DPPH and NO, respectively. The EtOAc fraction inhibited AChE and BuChE enzymes with IC₅₀ values of 0.94 and 8.49 mg/mL, respectively. Our findings show that the plant may have polyphenol contents, in particular in the methanol extract and EtOAc fraction. These extracts showed considerable free radical scavenging and cholinesterase inhibitory properties. Thus, the observed bioactivities may serve as a justification for its folkloric use as a remedy for mental illness. The study also provides relevant information that could help in the search for lead cholinesterase inhibitors from medicinal plants that can be exploited against neurodegenerative disorders.

Objective: The objective of the study was to evaluate the anti-inflammatory and antinociceptive effects of Artemisia afra.Methods: Animals were randomly divided into five groups of six animals each and administered with normal saline (2 ml/kg), indomethacin (10 mg/ kg), and A. afra at doses of 100, 200, and 400 mg/kg, respectively. For the anti-inflammatory activity, carrageenan-induced paw edema was used while the hot plate and acetic acid induced-writhing tests were used to assess the antinociceptive activity.Results: Pretreatment with A. afra at a dose of 100 mg/kg did not show any significant biological effects (p>0.05) for any of the three tests, when compared against saline-treated control group. At a dose of 200 mg/kg, A. afra demonstrated significant effects (p<0.01), during the 5th h reducing carrageenan-induced paw edema by 12%. The highest dose (400 mg/kg) of A. afra demonstrated more potent effects by decreasing the carrageenan-induced paw swelling (p<0.001–0.05) during the 3rd, 4th, and 5th h, by up to 38% when compared against saline-treated control group. Both the 200 and 400 mg/kg, A. afra doses achieved a significant increase (p<0.05) in reaction time in the hot plate test. In the acetic acid-induced writhing test, pretreatment with A. afra (400 mg/kg) significantly reduced pain by 39% (p<0.01) by comparison with the saline control.Conclusion: Experimental data demonstrated that aqueous extract of A. afra possesses anti-inflammatory and antinociceptive properties in experimental acute inflammation and pain. These findings support the usage of A. afra in managing inflammation and pain in traditional practice.

According to the World Health Organization, cancer is still the leading cause of death for humans worldwide. Although over 100 chemotherapeutic agents are currently available for the treatment of cancer patients, the overall long term clinical benefit is disappointing due to the lack of effectiveness or severe side effects from these drugs. The use of complementary and alternative medicinal products from plants has continued to increase in past decades, due to fewer side effects of bioactive compounds from medicinal plants of which pentacyclic triterpenoids have been identified as one class of secondary metabolites that could play an important role in the treatment and management of a number of non-communicable diseases. The main aim of this study is to extract, isolate, identify, and elucidate pentacyclic triterpenoid (ursolic acid, UA (1), and oleanolic acid, OA (2)) from Mimusops caffra. Semi-synthesis of UA was carried out to obtain some triterpenoid derivatives (3-O-acetyl ursolic acid, AUA (3), ursolic-28-methylate, UM (4), and 3-acetylursolic-methylate, AUM (5)), and we evaluated these compounds as anti-cancer therapeutic agents. Isolation of ursolic acid (UA) (1) from M. caffra is always accompanied by its isomer oleanolic acid (OA) (2) due to their similar retention factors (Rf) values. Acetylation and deacetylation techniques were used to isolate compounds 1 and 2. In vitro cytotoxicity activities of UA, AUA UM, and AUM were evaluated against various cancer cell lines, such as human breast adenocarcinoma cancer cell lines (MDA), human liver cancer cell lines (HepG2), human prostate cancer cell lines (PC3) and non-cancerous human fibroblast cell lines (KMST-6) using MTT assays. The UM exhibited remarkable cytotoxic activities against cancer cells, while little or no activities were observed on non-cancerous cell lines, which indicates that the addition of methyl at C-28 of UA is essential to enhance its activity as a therapeutic agent for cancer. The AUA showed moderate or no cytotoxicity against the different cancer cell lines, which is less than that of the UA parent compound. Moreover, these results suggest that ursolic acid and UA derivatives are potential therapeutic drugs for human breast, liver, and prostate cancers.