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The present study investigates the phytochemicals and thin layer chromatographic profile of Nauclea diderrichii (Rubiaceae) leaf extracts. Phytochemical in the hexane, ethyl acetate and methanol extracts were determined using standard chemical tests. Thin layer chromatographic techniques were carried out using various solvent systems of varying polarity on these extracts. Preliminary phytochemical screening revealed the presence of alkaloids, glycosides, saponins, phenolic compounds, tannins, phytosterols, carbohydrates, flavonoids and terpenoids. Further screening using thin layer chromatographic technique on the N. diderrichii leaf extracts also revealed different phytochemical compounds with different R f values. The results obtained in present study indicated that Nauclea diderrichii leaf is a rich source of phytochemicals. This could justifies the use of plant species in traditional medicine for treatment of various diseases.

Studies have shown that Chlorpyrifos (CPF), an Organophosphate (OP) insecticide alters both sex and thyroid hormones. Apart from inhibiting Acetylcholinesterase (AChE) activity, CPF has been shown to cause oxidative stress. The antioxidant potentials of many flavonoid-containing plants are increasingly being exploited in the therapy of many infectious and non-infectious diseases. Hibiscus Sabdariffa (HS) is one of the most widely used nutraceuticals that has been used traditionally to combat various illnesses due to its high flavonoid contents. The present study was therefore aimed at evaluating the ameliorative potentials of HS on subchronic chlorpyrifos-evoked alterations in sex and thyroid hormones in male Wistar rats. Forty-two (42) young adult male Wistar rats were divided at random into six groups containing seven (7) rats per group. Group I was administered distilled water (2 mL kg −1 ) only while group II received soya oil (2 mL kg −1 ), Group III was dosed with only aqueous extract of HS (500 mL kg −1 ~ 1/10 th of the LD 50 ), while group IV was given CPF (10.6 mL kg −1 ~ 1/8 th of the LD 50 ). Group V was pretreated with low dose of HS (250 mg kg −1 ~ 1/20 th of the LD 50 ) and then administered reconstituted CPF (10.6 mg kg −1 ), 30 min later. Group VI was pretreated with high dose of the HS (500 mg kg −1 ) and then administered CPF (10.6 mg kg −1 ), 30 min later. The regimens were administered orally by gavage once daily for a period of 11 weeks. At the end of the treatment period, sera obtained from the blood samples were analyzed for the levels of Follicle-Stimulating Hormone (FSH), Luteinizing Hormone (LH), testosterone, thyroid hormones (T 3 , T 4 and TSH) and AChE. Thyroid and pituitary glands of each rat were also evaluated for Malondialdehyde (MDA) concentration. Results showed a non-significant (p>0.05) decrease in the concentrations of FSH, LH and testosterone in the CPF group relative to the other groups. There was significant decrease (p<0.05) in the concentrations of T 3, T 4 and an increase in TSH in the CPF group relative to the other groups. There were significant increases (p<0.05) in MDA concentrations in the thyroid and pituitary glands in the CPF group compared to the other groups. Pretreatment with aqueous extract of HS demonstrated a dose-dependent amelioration of CPF-induced alterations in the levels of testosterone, LH, FSH, AChE, T 3 , T 4 and TSH in the serum and that of pituitary and thyroid glands MDA. This may be partly due to its high level of polyphenolic compounds that confer its antioxidant and possibly AChE restoration AJPTactivities. It is therefore concluded that pretreatment of individuals who are occupationally exposed to CPF and probably other OPs with the extract of HS may result in protection from the insecticideinduced adverse reproductive health outcomes.

Moraea pallida Bak. (yellow tulp) poisoning is the most important cardiac glycoside-induced intoxication in ruminants in South Africa. The toxic principle, 1α, 2α-epoxyscillirosidine, is a bufadienolide. To replace the use of sentient animals in toxicity testing, the aim of this study was to evaluate the cytotoxic effects of epoxyscillirosidine on rat embryonic cardiomyocytes (H9c2 cell line). This in vitro cell model can then be used in future toxin neutralization or toxico-therapy studies. Cell viability, evaluated with the methyl blue thiazol tetrazolium (MTT) assay, indicated a hormetic dose/concentration response, characterized by a biphasic low dose stimulation and high dose inhibition. Increased cell membrane permeability and leakage, as expected with necrotic cells, were demonstrated with the lactate dehydrogenase (LDH) assay. The LC50 was 382.68, 132.28 and 289.23 μM for 24, 48, and 72 h respectively. Numerous cytoplasmic vacuoles, karyolysis and damage to the cell membrane, indicative of necrosis, were observed at higher doses. Ultra-structural changes suggested that the cause of H9c2 cell death, subsequent to epoxyscillirosidine exposure, is necrosis, which is consistent with myocardial necrosis observed at necropsy. Based on the toxicity observed, and supported by ultra-structural findings, the H9c2 cell line could be a suitable in vitro model to evaluate epoxyscillirosidine neutralization or other therapeutic interventions in the future.

Background Terminalia avicennioides Guill and Perr (Combretaceae) is an important West African medicinal plant. The plant is used locally against microbes and parasites in both humans and animals and studies have demonstrated its cytotoxicity potential. Thus, this study was carried out to test the cytotoxic effect of the extracts and fractions of the root of the medicinal plant Terminalia avicennioides Guill and Perr (Combretaceae) in two different cell lines. Methods Methanol, ethanol, 30 % ethanol, hot water and cold water extracts and ethylacetate, hexane, chloroform, butanol and residual water fractions, were evaluated at 1000, 750, 500, 250, 100 and 50 µg/mL concentrations, with doxorubicin as positive control. The cells were incubated with the extracts for 48 h at 37 °C in a 5 % CO2 humidified incubator. The inhibition of cell viability, determined with the methyl blue thiazole tetrazolium bromide (MTT) assay, was used to assess the anti-proliferative effect of the extracts, in normal Vero Monkey kidney and human liver cancer (HepG2) cell lines. Results There was a concentration-dependent inhibition of cell viability in both the HepG2 and Vero cell lines. For HepG2 cells, antiproliferative effect was highest for the hexane fraction (viability ranged from 19.63 ± 1.10 % to 70.30 ± 1.78 % for 1000 and 50 µg/mL, respectively. For Vero cells, the highest antiproliferative effect, at 1000 µg/mL, was with hexane fraction (cell viability 21.37 ± 3.50 %), while at 50 µg/mL the chloroform fraction demonstrated the highest effect (viability of 86.10 ± 1.95 %). Conclusions The extracts and fractions from the root of Terminalia avicennioides have antiproliferative effect on the Vero and HepG2 cell lines tested. However, the extracts and fractions were not more toxic to the HepG2 than to the Vero cells. The cytotoxic effect of stem-bark and leaf extracts could be evaluated in the future to determine its anticancer potential.