Annual Research & Review in Biology

Aims: To investigate biological activities for neuroprotective effect of Catharanthus roseus.

Methodology: Catharanthus roseus was identified using DNA barcoding, utilizing matK, trnH-psbA, and rbcL markers. Additionally, thin-layer chromatography (TLC) method was used to analyze the phytochemistry compounds present in the C. roseus extracts. Moreover, acetylcholinesterase (AChE) inhibition activity was tested using a modified Ellman’s method. Finally, neurite outgrowth activity was determined in rat glial C6 cells treated with varying concentrations of C. roseus extracts.

Results: Overall, the plant samples which were collected in Laocai, Vietnam were successfully identified through DNA barcoding regions, using trnH-psbA, matK, and rbcL genes. Phytochemical analysis detected the presence of sterols, terpenoids, flavonoids, polyphenolic in the ethanol extract and its fraction from C. roseus. Additionally, the extracts of C. roseus displayed remarkably high acetylcholinesterase inhibitory activity. Moreover, the ethanol extract of C. roseus shown the most potent neurotrophic activity in a preliminary cell-based screening based on C6 cells neurite outgrowth.

Conclusion: These results demonstrate that Catharanthus roseus could be a strong candidate for developing pharmacological drugs to treat neurodegenerative diseases.

Aims: To determine the nutrient digestibility and blood composition of broiler chickens fed biodegraded sweet orange fruit peel-based diets.

Study Design: Completely randomized design.

Place and Duration of Study: Livestock Research Farm, Federal University of Agriculture Makurdi, Nigeria; fifty-six days

Methodology: Sweet orange peels and cattle rumen content were collected. Rumen content was mixed with water at a ratio 1 kg: 1 litre and sieved to get rumen filtrate (RF). RF was mixed with Sweet orange peels at a ratio of 1 litre: 2.5 kg and fermented for 48 hours, sun-dried, milled, and added to broiler diets at different levels: 0% (T1), 5% (T2), 10% (T3), 15% (T4), and 20% (T5). A total of 150 day-old chicks, randomly assigned to five dietary treatments and three replicates per treatment were raised in a 56-day feeding trial. Three chickens of average live body weight similar to the treatment group average were selected and used to determine nutrient digestibility and blood composition.

Results: The results showed that the coefficient of digestibility of dry matter, crude protein, crude fibre, ether extract and nitrogen-free-extract did not differ significantly (P > .05) among the treatment groups. Haematological indices; haemoglobin, red blood cell (RBC), packed cell volume, mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH), did not differ significantly (P > .05) across the dietary groups, while white blood cell (WBC) and mean corpuscular haemoglobin concentration (MCHC) varied significantly (P < .05). Serum indices; total protein (TP), globulin, glucose, cholesterol, and alkaline phosphatase were significantly affected (P < .05) by the experimental diets, while albumin, aspartate transaminase and alanine transaminase did not differ significantly (P < .05) across the dietary groups.

Conclusion: Biodegraded sweet orange peel-based diets can replace maize grains up to 20% without affecting nutrient digestibility or having any adverse effect on blood constituents of broiler chickens.

One of the major constraints related to maize (Zea mays L.) productivity is low soil fertility related mainly to continuous cropping without replenishment of depleted nutrients. In view of this, this study sought to assess the effect of different combinations of primary and secondary nutrients on the yield of maize in the Wenchi Municipality in the Brong-Ahafo Region. Five treatments - Control (T1), NPK (T2), NPK + S + Mg + Ca+ B + Cu + Mo+ Zn (T3), Manure (T4) and T3 + Manure (T5) - were tested in a field experiment in a randomized complete block design (RCBD) with four replicates. The test crop was Lake 601 maize variety.

Data for the research was collected on total number of plants, stalk weight, hurst weight, cob weight, grain weight Nutrient Use Efficiency and Economic Viability. The data was analysed with analysis of variance (ANOVA) on all measured parameters and the results were presented in graphs. From the results gathered, it was realized that the application of NPK + Sec_MN had a more positive impact on dry shoot weight and grain weight.

The results obtained from the field experiment also indicated that it was more efficient to combine both NPK and secondary nutrients in maize production compared to applying the other treatments assessed in the study; such that, the combined effect gave more yield and subsequently generated more money (income).

Based on the results obtained in the research, it was recommended that; much attention should be given to T3 (NPK + Sec_MN). Possibly, different doses of this treatment should be further tested to know the actual extent at which the secondary nutrients and the NPK can be combined to give the maximum yield. Similar research should also be staged at a different location to know whether similar results would be obtained.

Aim: Khaya senegalensis is one of the key medicinal plants used discretionarily in traditional medicine as remedies to several health conditions. This study aimed to establish the safety of Khaya senegalensis root aqueous extract in experimental animals with the purpose of optimizing its therapeutic value. 

Methodology: A total of 74 animals (20 rats and 54 mice) were randomly assigned into two main groups based on toxicity plan; acute and sub-chronic toxicity. Mice were divided into 9 groups (6 per group) for the acute toxicity study while rats were divided into 4 groups (5 per group) for sub-chronic toxicity assessment. 

Results: The acute concentrations of the extract in mice induced dose-dependent clinical signs severities such as: twitching, increase rate of respiration, sedation, abdominal muscle contractions and increased motor activity. The lethal dose 50 value of the extract was estimated as 320mg/ kg body. The sub-chronic concentrated grades in the rats especially the higher doses elicited significantly increased serum liver enzymes values when compared to the control, while at low dose the values were comparable to that of the control. Also observed were the evidences of renal cellular pathology ranging from mild to severe tubular cell degeneration, tubular cell depletion and congestion of the renal cortex. The liver pathologies such as hepatic portal congestion, cytoplasmic vacuolations and nuclear degeneration were strikingly visible mostly at the higher doses. The lymphocyte and platelet counts were the only haematological parameters that increased significantly more particularly at low dose when compared with the control.

Conclusion: This study has shown that Khaya senegalensis seems to be safe only at low doses. However, caution should be taking in its administration for therapeutic purposes especially when long-term usage is desired.

Azadirachta indica (Neem) and Ociumum gratissimum (clove Basil) have long been employed locally for the management of malaria. The present study compared antimalaria activities of the ethanolic leaf extracts of the individual plants, and assessed their combined effects on some organs of malaria-infected mice, at the Parasitology and Histopathology units, Federal Medical Centre (FMC), Owerri, from January to March, 2021. The leaves of the different plants were extracted with absolute ethanol (BDL 95%) for the test. Clean albino mice were experimentally infected intraperitoneally with chloroquine-sensitive Plasmodium berghei NK65 strain. Parasitaemia level was determined before parasite inoculation and at 24 hours post treatment period. Histopathological study on the liver, kidney, and heart was carried out using the Paraffin Setions method. Extracts of the leaves were administered orally, while chloroquine administration was intramuscular. The efficacy of the leaf extracts was tested on the P. berghei infected albino mice using the 4-day  curative test. The lethal median dose (LD₅₀) recorded for neem and clove basil leaf extracts were 31.62 and 1246.9 mg/kg body weight, respectively. Significant activity against the parasite was produced by infected mice treated with extracts of A. indica and O. gratissimum, and their combinations throughout the treatment period (P<.05). Highest reduction of parasitaemia was observed on day 4. Maximum parasitaemia reduction (78.65%) was attained with 30mg/kg of the combined extracts on the 7^th day. Mild pathological lesions were observed in mice treated with A. indica leaf extract. These observations indicate better anti-malaria activity of the combination therapy as compared with the individual extracts of A. indica and O. grassimum, and indicate good antimalarial and protective roles of the plant extracts on the parasitized mice at large, as it slows down development of resistance.