Hepatotoxic Effect of Aqueous Extract of Parkia biglobosa Seeds on Adult Albino Wistar Rats

Background: Parkia biglobosa belongs to the plant family Fabaceae and is popularly known as the African locust bean tree is gotten from medium-sized, tree high (20-20 cm), whose leaves are edible and are used in many African local dishes. The phytochemical screening of the methanolic extracts of P. biglobosa revealed the presence of saponins, tannins, terpenes, and phenols, reducing sugars, sterols, flavonoids. Methods: 21 adult Wistar rats (100-120 g) were distributed into 3 groups (A, B and C) consisting of 7 in each. Group B and C were administered orally with aqueous seed extract of P. biglobosa at a dose of 300 mg/kgB wt and 500 mg/kg B wt, respectively for 30 days. Group A was normal control and received 300 mg/kgB wt of normal saline. After 30 days, the weights were recorded and the animals were sacrificed using cervical dislocation. The changes in body weight, liver histology and enzymes were evaluated. Results: This study shows a significant difference (p<0.01) in the body weight gain between animals in the low, high and control groups, respectively. Photomicrograph of the liver tissue from animals in low dose reveals a liver cytoarchitecture with mildly dilated sinusoids, while the liver tissue from animals high dose group revealed a portal tract with dilated sinusoids. Results from histochemical observation of the liver of the control group showed marked periodic Acid Schiff (PAS) staining on predominant hepatocytes but little or no staining of cytoplasm, the low dose reveals a mild PAS staining while that of high dose shows moderate staining on tissue degeneration. Serum chemistry revealed a significant increase (p<0.05) AST and ALT in the test groups when compared to control group. Conclusion: Results from this study shows that the aqueous extract of P. biglobosa at a dose of 500 mg/kgB wt over 30 days may have adversely affected the morphology of the liver with the increase in serum levels.

Phenolic extract of Parkia biglobosa fruit pulp stalls aflatoxin B1 – mediated oxidative rout in the liver of male rats

The effect of phenolic extract of Parkia biglobosa (Jacq.) R. Br. ex G. Don, Fabaceae, pulp on aflatoxin B1 induced oxidative imbalance in rat liver was evaluated. Thirty-five male rats were randomized into seven groups of five animals each. Rats in group A served as control and received vehicle for drug administration (0.5% DMSO) once daily at 24 h intervals for six weeks. Rats in groups B, D, E, F and G, received aflatoxin B1 (167 μg/kg body weight) in 0.5% DMSO for three weeks, starting from the third week of the experimental period. Rats in Group C received 400 mg/kg bodyweight of the extract for six weeks, while groups D, E and F rats were treated with 100, 200 and 400 mg/kg bodyweight of the extract for six weeks respectively. Group G rats received 100 mg/kg body weight of vitamin C. Aflatoxin B1-mediated decrease in the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase were significantly attenuated. Aflatoxin B1 mediated the elevation in malondialdehyde, conjugated dienes, lipid hydroperoxides, protein carbonyl, and significantly lowered DNA fragmentation percentage. Overall, the phenolic extract of P. biglobosa pulp stalls aflatoxin B1-mediated oxidative rout by enhancing antioxidant enzyme activities leading to decreased lipid peroxidation, protein oxidation and DNA fragmentation.

Sourcing Starter Cultures for Parkia biglobosa Fermentation Part II: Potential of Bacillus subtilis Strains.

Aim: To select good strains of Bacillus subtilis for use as starter culture in the fermentation of Parkia biglobosa. Study Design: Fifteen (15) strains of Bacillus subtilis group obtained from commercial samples were used in starter-culture fermentation of Parkia biglobosa seeds to produce ‘iru’. Place and Duration of Study: Food Biotechnology Research Unit, National Center for Genetic Engineering and Biotechnology (BIOTEC), Pahumthani, Thailand, between March to May 2010. Methodology: The quality of the starter culture-fermented products were compared on the bases of sensory evaluation, degree of hydrolysis (DH), level of ammonia nitrogen (NH3-N), pH and enzymatic activities. The 15 strains were also screened for haemolytic activity. Results: On the basis of the sensory scores of 5 parameters (color, odor, consistency, texture and over-all liking), particularly the over-all liking, 5 strains were rated the best (in descending order): BC4333 > 8B > 2B > 7A > 5A, amongst the 15 tested. There were good correlations between pH and DH (r= 0.926), DH and NH3-N (r=0.962) and between pH and NH3-N (r=0.945). The strain BC4333 produced the very soft variant of ‘iru’ (‘iru-pete’), without the addition of ‘kuuru’ (local potash). The quantity of extracellular enzymes (protease, amylase, pectinase, phytase and lipase) produced during fermentation varied significantly. None of the 5 strains was haemolytic on sheep blood agar. Conclusion: The 5 strains of Bacillus subtilis (BC4333, 8B, 2B, 7A, 5A) that showed potentials of being used as starter cultures for industrial production of ‘iru’, were nonhemolytic on blood agar.

Evaluation of cardioprotective effects of Parkia biglobosa (Jacq. Benth) Mimosaceae stem bark.

Parkia biglobosa is one of the main medicinal plants used in traditional medicine to treat cardiovascular diseases in Africa. We investigated cardioprotective effects of stem bark hydro-alcoholic extract (HAE) of P. biglobosa in isoproterenol (ISO) induced myocardial infarction (MI). Four groups of five Wistar rats of each were used. Group I, control group, received per os (p.o) saline solution (5ml kg-1 b.w.) as vehicle daily for 15 days and was injected subcutaneously with the vehicle (5ml kg-1 b.w.) at an interval of 24 hours, on day 14 and 15. Group II referred to as infarcted rats, received vehicle p.o and was injected subcutaneously with isoproterenol (125 mg kg-1 b.w.) as in group I. Groups III and IV were pre-treated p.o with HAE (90 and 60 mg kg-1 b.w. respectively) daily for 15 days and was injected subcutaneously Isoproterenol (125 mg kg-1 b.w.). ISO has induced MI, characterized by significant increased (p <0.001) of MDA, biochemical alterations, heart hypertrophy and histological changes in infarcted rats. HAE, prevented significantly (p <0.001) induction of all these anomalies in pre-treated rats. These results suggested cardioprotective effects of P.biglobosa against ISO induced MI.

Bioactive compounds of the stem bark of parkia biglobosa.

Phytochemistry, elemental analysis and Infra red spectroscopy were used in combination to confirm the bioactive compounds encountered in the aqueous fraction of the extract of the stem bark of Parkia biglobosa. Bioautography results obtained confirmed the activity of these compounds singly and in combination against Staphylococcus. aureus and Pseudomonas aeruginosa -all organisms of medical and pharmaceutical importance. All results obtained brings us closer to the real identity of these compounds. Work is going on in our laboratory for the structure elucidation of the compounds.