Journal of Advances in Biology & Biotechnology

Objective: To evaluate in vivo antioxidant activity of Mangifera indica cold aqueous leaf extract. 

Methods: A number of 50 adult flies were exposed to graded concentrations of Mangifera indca cold aqueous leaf extract, 2.5 mg/10 g diet, 5 mg/10 g diet and 10 mg/10 g diet for 5 days. Each concentration was prepared in 200 µl of distilled water and replicated five times. 10 g diet with 200 µl distilled water served as control. Mortality reading was taken at 24 hours interval. The flies were homogenized, centrifuged and the supernatant was used to assay for Glutathione-S-transferase (GST), Catalase (CAT) and Total thiol content.

Results: The % mortality of flies after 5 days showed 32.5%, 0%, 15.5% and 37% in the control (10 g diet with 200 µl of distilled water), 2.5 mg/10 g diet, 5 mg/10 g diet and 10 mg/ 10 g diet respectively. There was elevation in total thiol content and high GST and CAT activity in 2.5 mg/10 g diet and 5 mg/10 g diet treated flies.

Conclusion: The 100% and 85% survival of 2.5 mg/10 g and 5 mg/10 g diet-treated flies respectively and increase of fly antioxidant system after 5 days exposure at these concentrations may suggest protective activity of Mangifera indica in D. melanogaster.

This study investigated the effects of stock age, hormones and hormone concentrations on survival and rooting of Vitellaria paradoxa stem cuttings with the aim of improving on early development of the species. Single node stem cuttings were obtained from 9 and 15 months old seedlings of V. paradoxa and treated with Naphthalene Acetic Acid (NAA), Indole Butyric Acid (IBA), unripe coconut water (CW) and distilled water (control) at 100 mg/l and 200 mg/l concentrations NAA, IBA and 50% and 100% coconut water. Quick dip method was used and the cuttings set in washed and sterilized river sand medium under non-mist propagation in a 2x4x2 factorial experiment laid out in Completely Randomized Design and replicated 3 times. Percentage rooted and percentage die-back were assessed after eight weeks of setting while shoot height (cm), shoot diameter (mm), leaf production and leaf area (cm²) were assessed for three months. The data collected were subjected to descriptive statistics and analysis of variance (ANOVA). Cuttings from both 9 months and 15 month old stocks recorded higher percentage (90%) with NAA hormone treated cuttings and also produced the highest rooting at (90%) while control recorded the least (50%). Hormone type also significantly influenced the early growth of the rooted cuttings in term of shoot height, shoot diameter, leaf area and leaf production (p≤0.05). The highest shoot height, shoot diameter, leaf area and number of leaves were obtained with NAA with mean values of (4.81 cm, 3.46 mm, 35.08 cm² and 5.00) respectively while control had the least (3.80 cm, 2.28 mm, 27.81 cm² and 3.29) respectively. It therefore implies that the use of hormones can improve rooting and early growth of V. paradoxa stem cuttings collected from young stock plants.

Aims: The present study was carried out to investigate the toxic effects of the Oxalis barrelieri aqueous aerial parts extract.

Place and Duration of Study: Department of Biological Sciences (Animal Physiology Laboratory), Higher Teachers’ Training College, University of Yaoundé I. Between April 2017 and June 2018.

Materials and Methods: Acute toxicity using a single dose of 2000 mg/kg was administered to mice and effects were observed for 14 days. In sub-acute toxicity, the experimental rats (males and females) received aqueous extract of Oxalis barrelieri at doses of 200 mg/kg, 400 mg/kg and 800 mg/kg daily for 28 days while the control and satellite control groups received distilled water and satellite test group received extract at the dose of 800 mg/kg. The physical parameters were evaluated throughout the treatment, while the haematological, biochemical and histological parameters were evaluated at the end of the treatment.

Results: In acute toxicity, the results obtained show no death and no significant variation (p>0.05) in behavioral and morphological parameters. In sub-acute toxicity assay, few modifications were observed in haematological and biochemical parameters. At the higher dose of extract (800 mg/kg),the rate of red blood cells decreased significantly (p<0.05) two weeks after treatment in male rats , there were a significant increase (P˂0.001) in ASAT activity in male and female rats two weeks after extract administration, and a reversible significant increase (P˂0.05) in triglyceride level in male rats only. Histopathology showed a reversible slight dose dependent structural alteration of the kidney and reversible vascular congestion in liver.

Conclusion:  The aqueous aerial parts extract of Oxalis barrelieri could possess moderate toxicity at high doses and adequate caution should be exercised in its use in ethnomedicine.

Aim: Ocimum gratissimum is commonly used as food and health purposes. This study is aimed at evaluating the bioactive compounds and antibacterial activity of leaf extract of O. gratissimum against Salmonella species.

Methodology: The Phytochemical screening of O. gratissimum was conducted using standard methods. Screening for antibacterial activity of the leaf extracts against Salmonella species was determined using agar well diffusion method. An in-vivo toxicity study was carried out with albino rats.

Results: The phytochemical screening revealed the presence of saponins, tannins, cardiac glycoside, flavonoid, glycosides, alkaloid, volatile oils and steroids. A zone of inhibition of 14mm was recorded against the organisms using ethanolic extract with a concentration of 100 mg/ml and the lowest was recorded against Salmonella paratyphi with the concentration of 25 mg/ml of the ethanolic extract. Zone of inhibition of 9.00 mm and 10.0mm was recorded against S. typhi and S. paratyphi on a concentration of 100 mg/ml of the aqueous extract. A minimum inhibitory concentration of 100 mg/ml and 25 mg/ml of the aqueous and ethanolic extract of the leaf was recorded. After the toxicity test, no death was recorded after 2 (two) weeks.

Conclusion: The leaf extract of O. gratissimum shows promising potentials in the treatment of infectious diseases associated with Salmonlla typhi and Salmonella paratyphi, due to its antimicrobial activity and low toxicity. However, further studies are needed to non-polar solvents to isolate other bioactive compounds as well as identify the active metabolites responsible for these activities.

Due to increased global warming and pollution, the use of biodiesel as alternative to biodiesel has become a widespread. The use of Mustard (Brassica juncea L.) oil as a possible feedstock for biodiesel production was evaluated. The biodiesel was produced through transesterification with sodium hydroxide and gave a biodiesel yield of 94 wt.%. The fatty acid profile obtained by chromatography analyzer was mainly erucic acid 45.7 wt.%, linoleic acid 14.2 wt.% and linolenic acid 13.0 wt.% acids. The distillation characteristics show higher distillation temperature than diesel and the mineral elements in the oil and biodiesel are within the ASTM limits for biodiesel. The oil and biodiesel were characterized and they gave properties that are similar to those of fossil diesel and within the ASTM D6751 and EN 14214 limits for biodiesel, which led to the conclusion that mustard seeds can be a viable source of feedstock for biodiesel production. The glycerin analysis shows the completeness of the transesterification process.