Morella serrata (Lam.) Killick stabilizes biomembrane and rejuvenates sexual competence in male Wistar rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Morella serrata L. is an indigenous medicinal plant to South and southern Africa with folkloric applications as aphrodisiac, laxative, antimicrobial, anti-inflammatory, analgesic, anti-hypertensive, antitussive and antidiabetic agent. AIM OF THE STUDY: This study evaluated the membrane stabilization and aphrodisiac potentials of its aqueous root extract in male Wistar rats. MATERIALS AND METHODS: While the membrane stabilization of the extract was investigated against bovine erythrocytes (BE), the male rats for the aphrodisiac study were randomized into five groups with animals in group 1 given sterile placebo and served as control. The rats in group 2 were treated with 7.14mg/kg body weight of PowMaxM, while animals in groups 3, 4 and 5 were administered with the extract (100, 200 and 400mg/kg, respectively). All treatments (1mL) were done once daily for 4 weeks via oral gavaging and their mating behavioural, testicular, spermatogenetic and antioxidant parameters were evaluated. RESULTS: With the exception of the mount, intromission and post ejaculatory latencies that were dose-dependently reduced by the extract, other mating parameters were significantly improved when compared with the control. Similar patterns of significant improvement were also observed on the testes-body weight ratio, quality and viability of sperm cells as well as testicular concentrations of proteins, cholesterol, glycogen, testosterone, follicle stimulating hormone, leuitenizing hormone and glutathione (reduced) subsequent to treatment with the extract. Although, administration of M. serrata had no significant (p>0.05) effect on the testicular activity of gamma glutamyl transferase, those of lactate dehydrogenase, phosphatases (alkaline and acid), superoxide dismutase and catalase were significantly (p<0.05) induced in the treated animals. The extract also conferred respective significant (p<0.05) membrane stabilization potential of 66.02% and 60.87% on the BE against hypotonic solution and heat-induced hemolysis relative to 62.14% and 40.19% for ibuprofen. The effect elicited by the extract at the tested doses could partly be attributed to its antioxidant and adaptogenic constituents. CONCLUSION: The data presented in this study have enriched biochemical information on the root extract of M. serrata as a viable source of phytonutrients that could be potentially useful for the development of aphrodisiac drugs, and thus lending scientific credence to its much touted sex enhancing attributes by the Basothos of the eastern Free State Province of South Africa.

Membrane Stabilization and Detoxification of Acetaminophen-Mediated Oxidative Onslaughts in the Kidneys of Wistar Rats by Standardized Fraction of Zea mays L. (Poaceae), Stigma maydis.

This study evaluated membrane stabilization and detoxification potential of ethyl acetate fraction of Zea mays L., Stigma maydis in acetaminophen-induced oxidative onslaughts in the kidneys of Wistar rats. Nephrotoxic rats were orally pre- and posttreated with the fraction and vitamin C for 14 days. Kidney function, antioxidative and histological analyses were thereafter evaluated. The acetaminophen-mediated significant elevations in the serum concentrations of creatinine, urea, uric acid, sodium, potassium, and tissue levels of oxidized glutathione, protein-oxidized products, lipid peroxidized products, and fragmented DNA were dose-dependently assuaged in the fraction-treated animals. The fraction also markedly improved creatinine clearance rate, glutathione, and calcium concentrations as well as activities of superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase in the nephrotoxic rats. These improvements may be attributed to the antioxidative and membrane stabilization activities of the fraction. The observed effects compared favorably with that of vitamin C and are informative of the fraction's ability to prevent progression of renal pathological conditions and preserve kidney functions as evidently supported by the histological analysis. Although the effects were prominently exhibited in the fraction-pretreated groups, the overall data from the present findings suggest that the fraction could prevent or extenuate acetaminophen-mediated oxidative renal damage via fortification of antioxidant defense mechanisms.

Kinetics of α-amylase and α-glucosidase inhibitory potential of Zea mays Linnaeus (Poaceae), Stigma maydis aqueous extract: An in vitro assessment.

ETHNOPHARMACOLOGICAL RELEVANCE: Corn silk (Zea mays L., Stigma maydis) is an important herb used traditionally in many parts of the world to treat array of diseases including diabetes mellitus. Inhibitors of α-amylase and α-glucosidase offer an effective strategy to modulate levels of post prandial hyperglycaemia via control of starch metabolism. AIM OF THE STUDY: This study evaluated α-amylase and α-glucosidase inhibitory potentials of corn silk aqueous extract. Active principles and antioxidant attributes of the extract were also analysed. MATERIALS AND METHODS: The α-amylase inhibitory potential of the extract was investigated by reacting its different concentrations with α-amylase and starch solution, while α-glucosidase inhibition was determined by pre-incubating α-glucosidase with different concentrations of the extract followed by addition of p-nitrophenylglucopyranoside. The mode(s) of inhibition of the enzymes were determined using Lineweaver-Burke plot. RESULTS: In vitro analysis of the extract showed that it exhibited potent and moderate inhibitory potential against α-amylase and α-glucosidase, respectively. The inhibition was concentration-dependent with respective half-maximal inhibitory concentration (IC50) values of 5.89 and 0.93mg/mL. Phytochemical analyses revealed the presence of alkaloids, flavonoids, phenols, saponins, tannins and phytosterols as probable inhibitory constituents. Furthermore, the extract remarkably scavenges reactive oxygen species like DPPH and nitric oxide radicals, elicited good reducing power and a significant metal chelating attributes. CONCLUSION: Overall, the non-competitive and uncompetitive mechanism of action of corn silk extract is due to its inhibitory effects on α-amylase and α-glucosidase, respectively. Consequently, this will reduce the rate of starch hydrolysis, enhance palliated glucose levels, and thus, lending credence to hypoglycaemic candidature of corn silk.

Antioxidant and hepatoprotective activities of Dicoma anomala Sond. aqueous root extract against carbon tetrachloride-induced liver damage in Wistar rats.

OBJECTIVE: To evaluates the antioxidant and hepatoprotective potentials of Dicoma anomala Sond. (Asteraceae) on body weight, feed and water intake, biochemical parameters and organ histology. METHODS: Various concentrations (1.56-25 µg/mL) were used in the in vitro assays 1,1-diphenyl-2-picryl hydrazyl (DPPH, superoxide anion, hydroxyl radicals, etc.). The effects of treatment with 125, 250 and 250 mg/mL Dicoma anomala aqueous roots extract (DARE) was investigated in vivo in the CCl4-induced hepatotoxic rats during the 15 days study. RESULTS: Water extract exhibited the best activity (IC50: 15.20 ± 0.03, 11.70 ± 0.10, and 0.84 ± 0.05 µg/ mL) in vitro in DPPH, hydroxyl and superoxide anion radicals, respectively, when compared with standards. Pre-treatment and treatment with different concentrations of DARE significantly (P < 0.05) attenuated the elevated serum activities of aspartate transaminase, alanine transaminase levels while increasing the activities of superoxide dismutase, catalase and glutathione peroxidase. The histopathological evaluations revealed extensive liver damage characterized by severe vacuolar and cytoplasmic degeneration, hepatic necrosis, and cellular infilteration in pre-treated groups while in the treated groups; such liver damages were not observed most especially at 500 mg/kg dose. CONCLUSION: The results proved the hepatoprotective potential of DARE against CCl4-induced oxidative stress. Moreover, histopathological examinations revealed better therapeutic advantage of DARE than prophylactic use.

Antimicrobial activity of the solvent fractions from Bulbine natalensis Tuber.

Bulbine natalensis Baker has been acclaimed to be used as an antimicrobial agent in the folklore medicine of South Africa without scientific evidence to substantiate or refute this claim. In view of this, the in vitro antimicrobial activity of solvent fractions (ethanol, ethyl acetate, n-butanol and water) from Bulbine natalensis Tuber against 4 Gram positive and 12 Gram negative bacteria as well as 3 fungal species were investigated using agar dilution. The ethanolic extract, n-butanol and ethyl acetate fractions inhibited 75, 87.5 and 100% respectively of the bacterial species in this study. The ethanolic, n-butanol and ethyl acetate fractions produced growth inhibition at MIC range of 1-10, 3-10 as well as 1 and 5 mg/ml respectively whereas the water fraction did not inhibit the growth of any of the bacterial species. Again, it was only the ethyl acetate fraction that inhibited the growth of Shigelli flexneri, Staphyloccus aureus and Escherichia coli. The ethanolic, ethyl acetate and n-butanolic fractions dose dependently inhibited the growth of Aspergillus niger and A. flavus whereas the water fraction produced 100% growth inhibition of the Aspergillus species at all the doses investigated. In contrast, no growth inhibition was produced on Candida albicans. The growth inhibition produced by the solvent fractions of B. natalensis Tuber in this study thus justifies the acclaimed use of the plant as an antimicrobial agent. The ethyl acetate fraction was the most potent.

Toxicological evaluation of aqueous leaf and berry extracts of Phytolacca dioica L. in male Wistar rats.

Despite the widespread use of Phytolacca dioica L. in folklore medicine of South Africa, there is dearth of information on its safety/toxicity. The aim of this study was to evaluate the toxicological effect of aqueous leaf and berry extracts of the plant at different dosages for 14 days on the liver and kidney function indices in male Wistar rats. Phytochemical screening indicated that the extracts are rich in phytonutrients including alkaloid, tannin, saponins, phenolics, lectins and flavonoids; while triterpenoids and phlobatanins were absent. The extracts significantly reduced the body and absolute organ weights of the animals at all the dosages investigated. Whereas, significant increase was observed in the serum levels of alkaline phosphatase (ALP), gamma glutamyl transferase (GGT), alanine transaminase (ALT), aspartate transaminase (AST), bilirubin, calcium, creatinine, urea and uric acid; the serum concentration of total protein, albumin and globulin were reduced in the serum following treatment with the extracts. Generally, the effect of the herb appeared to be dosage dependent. This investigation clearly showed that P. dioica can impair normal hepatic and renal functions. This is an indication that the extracts may not be completely safe in male rats when continuously administered for 14 days.

In vitro antioxidant activity of extracts from the leaves of Felicia muricata thunb. An underutilized medicinal plant in the Eastern Cape Province, South Africa.

Felicia muricata is a medicinal plant used for the management of different human and livestock diseases in the Eastern Cape Province of South Africa. The antioxidant potential of the leaves from this herb was investigated using its water, methanol, acetone and ethanol extracts. All the extracts were rich in phenols, proanthocyanidins and flavonols but low in flavonoids. The water extract exhibited low DPPH scavenging activity while the methanol, acetone and ethanol extracts showed higher activities. Again all the extracts showed high ABTS scavenging activity with a correlation between total phenolic content (R2 = 0.9965), DPPH (R2 = 0.982) and ABTS (R2 = 0.927). Traditionally, however, plant extracts are prepared with water as infusions, decoction and poultice. Our results have shown that both the water and ethanol extracts from Felicia muricata displayed strong antioxidant activity. Therefore, it would seem likely that both solvents were able to extract those compounds which are responsible for the antioxidant activity of F. muricata.

Foliar micromorphology of Felicia muricata Thunb., A South African medicinal plant.

The foliar micromorphology of Felicia muricata (Thunb.) Nees (Asteraceae) was observed with the JEOL (JSM-6390LV) Scanning Electron Microscope (SEM). Both the abaxial and adaxial surfaces were characterized by anisocytic stomata which were more prevalent on the abaxial surface than the adaxial surface. The leaves have only one type of multicellular non-glandular trichomes that are long and cylindrical, tapering to a sharp point and running parallel to the leaf surface in the direction of the apices. Crystal deposits were also observed on the surfaces of the leaves near the stomata. Energy dispersive X-ray spectroscopy-SEM shows that Na, Al, Si, and K were the major constituents of the crystal analyzed. Since no glandular trichomes were present on the leaves of this herb, the bioactive components present in this plant may be produced in some other tissues in the leaf other than the trichomes.