Nigerian Journal of Biochemistry and Molecular Biology

Introduction to NJBMB’s Fourth Issue for 2024: Advancing Biochemical Research for Health and Innovation

Ismaila A. Umar — 2024-12-31

It is with great pleasure that we present Volume 39, Issue 4 of the Nigerian Journal of Biochemistry and Molecular Biology (NJBMB), the official publication of the Nigerian Society of Biochemistry and Molecular Biology. This edition continues our commitment to advancing biochemical and molecular biology research by featuring high-quality studies that address critical scientific and health-related challenges.

The studies in this issue exemplify the breadth and depth of biochemical research, ranging from natural product pharmacology to forensic biochemistry, nutritional biochemistry, and disease pathogenesis. These contributions underscore the pivotal role of biochemistry and molecular biology in improving human health and scientific understanding.

The first study, by Tijjani et al., explores the glucose-lowering and antioxidant properties of Xylopia aethiopica seed extract, providing insight into its potential application in diabetes management and oxidative stress mitigation. Their findings highlight the importance of indigenous medicinal plants in disease prevention and therapeutic development.

Olawuni et al. investigate the neuroprotective potential of Ficus benjamina leaves in mitigating Alzheimer's disease pathology. Their study integrates in silico and in vitro approaches to evaluate the inhibitory effects of apigenin and kaempferol on key enzymes implicated in neurodegeneration. This research contributes to the growing field of natural compounds as alternative therapeutic strategies for neurodegenerative diseases.

Agoro and Thomas present an innovative forensic biochemistry study, utilizing vitreous lipid and protein biomarkers to differentiate between postmortem and true brackish water drowning cases. Their findings offer promising forensic applications in medico-legal investigations and criminal justice proceedings.

Babarinde et al. employ bioassay-guided fractionation to identify anti-inflammatory and xanthine oxidase inhibitory compounds from Zanthoxylum tessmannii roots. Their work not only supports traditional medicinal uses of the plant but also raises important considerations regarding potential allergenic effects of its bioactive constituents.

Faponle et al. examine the impact of common Nigerian starchy staple meals on postprandial glycemia. Their findings emphasize the need for dietary modifications in glucose metabolism disorders such as diabetes, reinforcing the crucial link between nutrition and health.

The publication of this issue would not have been possible without the dedication and expertise of numerous individuals. We extend our profound gratitude to the contributing authors for their rigorous research and scholarly contributions. Our sincere appreciation also goes to the editorial board, peer reviewers, copy editors, and the production team for their tireless efforts in ensuring the integrity and quality of the journal.

We hope that the insights presented in this issue will stimulate further research, inspire innovative applications, and contribute to the continued growth of biochemical and molecular biology sciences in Nigeria and beyond.

Thank you for your continued support, and we look forward to future ground-breaking discoveries that will shape the future of biochemical research.

Oral Glucose Tolerance and Protective Effect of Aqueous Extract of Xylopia Aethiopica Seed on 2,2-Azobis(2-Amidinopropane) Dihydrochloride (AAPH) Induced Oxidative Stress

Habibu Tijjani — 2024-12-31

In Nigeria, Xylopia aethiopica (Annonaceae) is locally used in tea and beverages, and in treating constipation. This study evaluated the oral glucose tolerance and protective effect of X. aethiopica seed extract on 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress in red blood cells (RBCs). Twelve experimental mice were randomly distributed into four groups of three mice administered orally with distilled water, metformin, and X. aethopica aqueous seed extract. Glucose was administered orally to 12 hour fasted mice, and plasma glucose was evaluated after 0-4 hours. Antioxidant activity was evaluated using prepared RBCs from mice after pre-treatment with AAPH. Significant increase (p < 0.05) was observed in glucose level of all treated mice after 30 minutes, which gradually decreased to 11.41%, 16.52%, and 14.19% for aqueous extract of X. aethiopica seed (250 and 500 mg/kg b. wt) and metformin (14.5 mg/kg b.wt) respectively. The antioxidant activity indicated that the extract possessed higher hydroxyl radical scavenging activity compared with vitamin C. More so, aqueous extract of X. aethiopica seed protected cells against AAPH-induced oxidative stress in cells by decreasing the activity of catalase generated and malondialdehyde concentration after 40 minutes of incubation at 2.5 mg/mL compared with vitamin C. No significant difference (p > 0.05) was observed in superoxide dismutase activity in vitro. The total tannin and phenolic contents of X. aethiopica seed were 509.16±192.13 mgQE/g and 1.59±0.63 mgGAE/g, respectively. The study concludes that aqueous extract of X. aethiopica seed possesses glucose-lowering and antioxidant detoxifying properties against 2,2-azobis(2-amidinopropane) dihydrochloride-induced oxidative stress in vitro.

Apigenin and Kaempferol from Ficus benjamina Leaves as Potential Inhibitors of Enzymes Relevant to Alzheimer’s Disease Pathology: An In Silico and In Vitro Study

Julius I. Olawuni — 2024-12-31

Alzheimer’s disease is a progressive neurodegenerative disease. In this report, we identified and evaluated polyphenol constituents from the leaves of Ficus benjamina, targeting enzymes relevant to the pathology of Alzheimer's disease. Polyphenols were extracted from the leaves of F. benjamina, subjected to LC-MS and GC-MS analyses. The constituents were subjected to In Silico analyses, targeting acetylcholinesterase (AChE), butyrylcholinesterase (BUChE), and beta-secretase 1 (BACE1). In vitro antioxidant (ferrous ion-chelating, copper reducing antioxidant, ferric reducing antioxidant power (FRAP), and total antioxidant capacity), and enzyme inhibitory (AChE, BUChE, and BACE1) assays, were performed using standard procedures. In silico analysis revealed that Apigenin and Kaempferol showed strong functional interactions with AChE, BUChE, and BACE1. Apigenin and Kaempferol showed potent antioxidant capacity with IC₅₀ values of 76.82 ± 0.95 µg/ml and 38.85 ± 0.68 µg/ml (Metal chelating assay); 63.77 ± 2.19 and 81.53 ± 2.54 mg AAE/g (FRAP assay); 166.90 ± 5.02 and 216.28 ± 8.20 mg AAE/g (Total antioxidant capacity); and 64.96 ± 0.80 and 86.09 ± 1.27 mg TE/g (CUPRAC assay) respectively. They also significantly inhibited AChE, BUChE, and BACE1 with IC₅₀values of 42.67 ± 0.76 µg/ml and 46.76 ± 0.61 µM (Apigenin) respectively. The evaluation of Apigenin and Kaempferol from F. benjamina confirmed their potential usefulness in Alzheimer’s conditions, and this could be due to their inhibitory action against the functional activities of AChE, BUChE, and BACE1.

Vitreous Lipid and Protein Biomarkers as Indicators of Brackish Water Drowning: A Forensic Biochemistry Study

Eni-yimini S. Agoro — 2024-12-31

Deaths resulting from submersion or immersion in water account for about 7% of trauma-induced mortalities. Several cases of drowning deaths are not unintentional but criminally disguised to evade justice. Also, the type of water body in which drowning occurred is important in making an empirical closure on the intent of occurrence. Therefore, this study was designed to utilize vitreous proteins and lipids in discriminating postmortem brackish water drowning from true brackish water drowning. Sixteen (16) albino rabbits constituted the sample size which were further divided into four (4) groups: the control (CD), the chloroform group (CFD), the postmortem drowned (PDD), and the brackish drowned death (BDD). Vitreous humours were extracted from the eyes of the animals, and consequently processed, and analysed for proteins and lipids. The results showed a significant decrease (P>0.05) in the concentration of vitreous albumin in PDD (0.190± 0.071) and BDD (0.109±0.043), when compared to the CD (0.485 ± 0.307), whereas it increased significantly (P>0.05) in CFD (1.837 ± 0.231). In a similar vein, there was a significant increase (P>0.05) in vitreous triacylglycerol in the experimental groups (CFD-0.218±0.116; PDD-1.051±0.627; BDD- 0.826±0.172) when compared to the controls (0.082±0.032). Additionally, the increase in vitreous triacylglycerol was more prominent in the PDD when compared to the BDD and CFD. The findings have revealed that vitreous albumin and triacylglycerol could be useful in discriminating against deaths resulting from brackish water drowning.

Bioassay-Guided Fractionation and Identification of Anti-Inflammatory and Xanthine Oxidase Inhibitory Compounds of Zanthoxylum tessmannii Roots

Samuel O. Babarinde — 2024-12-31

Several bioactive compounds identified in Zanthoxylum tessmannii have validated many traditional medicine applications of the plant. Studies have highlighted the anti-inflammatory properties of crude extracts of the plant and the allergenic properties of both extracts and fractions of the plant roots. This study aimed to identify the compounds responsible for these effects in Z. tessmannii roots. Using bioassay-guided fractionation, the aqueous extract was partitioned into n-hexane, dichloromethane, ethyl acetate, and butanol fractions, followed by partial purification of the most active fraction with silica gel chromatography. Fractions and sub-fractions were tested for inhibition of protein denaturation, xanthine oxidase (XO), and lipoxygenase activities. The aqueous fraction (AF) showed significantly higher inhibition of protein denaturation (46.74±2.17%) compared to dichloromethane (35.05±1.51%) and butanol (34.78±1.09%) fractions at concentrations of 0.0015 mg/mL and 0.003 mg/mL. AF also demonstrated the highest inhibition of XO activity. Sub-fraction A, from the most active AF, showed 93.19±0.08% inhibition of lipoxygenase. GC-MS analysis of sub-fraction A identified compounds like E-15-Heptadecenal, 9-Octadecenoic acid (Z)-2,3-dihydroxy propyl, trans-13-Octadecenoic acid, Oleic acid, and Tetraacetate 1-Hexanethiol. The findings highlight that Z. tessmannii root possesses compounds with known anti-inflammatory effects and those indicating allergenic symptoms, suggesting both therapeutic potential and possible harmful effects.

Postprandial glycemia: How do Starchy Staple Meals Contribute to Glycemic Responses in Healthy Human Subjects?

Abayomi S. Faponle — 2024-12-31

Postprandial blood glucose levels are influenced by starchy meals, which digest into glucose at different rates and have specific glycemic indices. These meals raise blood glucose concentrations at varying rates shortly after consumption. Therefore, consuming foods with minimal effects on postprandial blood glucose is beneficial for health and wellbeing. Starchy meals are staple foods in Nigeria, including rice, eba (cassava dough), and yam, which provide essential metabolic energy (glucose). This study evaluated the postprandial effects shortly after intake of these meals in 30 healthy individuals with body weights ranging from 40 to 85 kg, divided into six groups: a meal-deprived control group and five experimental groups, each with five participants. The meals tested were rice with fish stew, eba with jute leaf soup, and yam with egg sauce. Blood glucose levels were measured before the meal, after a 2-hour food deprivation, and at 10, 30, and 50 minutes post-meal. The results showed that rice caused the highest postprandial blood glucose spike (p ≤ 0.05), while yam with egg sauce resulted in no significant change (p > 0.05). The study concluded that rice significantly increases postprandial blood glucose levels, indicating a high glycemic response. Thus, reducing rice intake may help manage diseases related to glucose metabolism, such as diabetes.