Browsing by Author "Avwioroko, Oghenetega"

Now showing 1 - 20 of 42
  • Thumbnail Image
    Item
    Amelioration of Lead-induced Toxicity in Blood, Liver and Kidney Tissues of Male Wistar Rats by Fermented Ofada Rice
    (Turkish Journal of Agriculture - Food Science and Technology, 2015-08) Avwioroko, Oghenetega
    The protective effects of ‘ofada’ rice koji (ORK, fermented ofada rice) and ascorbic acid (AA) against lead (Pb)-induced toxicity in the blood, liver and kidney tissues of male Wistar rats was investigated. The animals were divided into four treatment groups (A – D, n = 5). Groups B, C and D were intoxified by intra-peritoneal injection of 75 mg lead acetate/kg body weight. Groups C and D only had their feed mixed with ORK and AA, respectively. The results showed no significant difference in % packed cell volume (PCV) and Pb concentrations. Feeding with ORK and AA significantly decreased alanine aminotransferase activities (36.50 ± 3.54 and 34.02 ± 0.05 UL-1 respectively) compared to Pb-only treated group (85.50 ± 3.25 UL-1). The ferric reducing antioxidant power (FRAP) for organs increased significantly following intake of feeds mixed with ORK and AA; increases in FRAP was higher for ORK-treated group possibly due to increased total flavonoids concentration following fermentation. Furthermore, Pb-induced high plasma creatinine levels decreased upon treatment with feeds mixed with ORK and ascorbic acid. These findings strongly indicated that feed supplementation with ORK by 45% may be more effective at ameliorating the effects of Pb-induced toxicity in tissues compared to supplementation with AA by 2%.
  • Thumbnail Image
    Item
    Amine-Modified Kaolinite Clay Preserved Thyroid Function and Renal Oxidative Balance after Sub-Acute Exposure in Rats
    (J Basic Clin Physiol Pharmacol, 2020) Avwioroko, Oghenetega
    Objectives: Kaolinite clay is an abundant natural resource in Nigeria with several industrial applications. Incidentally, the wide-scale use of kaolinite clay is hampered by its small surface area. The objective of this study was to assess the effects of amine-modified clay on electrolyte, thyroid, and kidney function markers. Methods: Modification of kaolinite clay with an amine functional group was achieved using surface grafting technique. Characterization with a scanning electron microscope and Brunauer-Emmett Teller surface area analyzer confirmed this modification. However, there is sparse information on the effect of amine-modified kaolinite clay on electrolyte homeostasis, thyroid, and renal function. Rats were administered amine-modified kaolinite clay at the doses of 1, 2, and 5 mg/kg body weight. Results: After 14 days of repeated-dose treatment, there were no significant changes in levels of albumin, uric acid, triiodothyronine, thyroxine, ratio of triiodothyronine to thyroxine, and relative kidney organ weight. Furthermore, there were no changes in the concentration of potassium, although amine modified kaolinite clay significantly decreased sodium, calcium, and total cholesterol levels. Amine modified kaolinite clay, at all treatment doses, also preserved the renal histoarchitecture and oxidative balance in rats. Conclusions: This study reports on the effect of aminemodified kaolinite clay on renal markers and thyroid function, and further deepens our understanding of their biochemical action. This baseline data may boost the prospect of using amine-modified kaolinite clay in the treatment of contaminated water.
  • Thumbnail Image
    Item
    Anti-diabetic Effect of Combined Treatment with Aloe vera gel and Metformin on Alloxan-Induced Diabetic Rats
    (Journal of Ayurvedic and Herbal Medicine, 2018) Avwioroko, Oghenetega
    Aim: The present study investigated the effects of intensive glucose regulation with combined treatment of Aloe vera gel (a herbal agent) and Metformin in an alloxan-induced diabetic rat model. Methods: Forty rats were assigned to the following groups and treated for 21 days: Group 1 (normal untreated control), Group 2 (untreated diabetic rats, DR), Group 3 (DR + 300 mg/kg PE of Aloe vera ), Group 4 (DR + 2 mg/kg Metformin) and Group 5 (DR + 300 mg/kg PE of Aloe vera + 2 mg/kg Metformin). The effect of the treatments on fasting blood glucose (FBG) level, lipid profile, renal function, atherogenic index, pancreas and kidney histopathologies were assessed. Results: FBG level in Group 5 rats decreased by 28.4, 38.0 and 69.0% at Day 7, 14 and 21, respectively. Hyperlipidaemia, high atherogenic index, increased plasma creatinine and urea levels observed in the diabetic rats were ameliorated by the single and combined treatments with Aloe vera and Metformin. Reduced level of HDL-cholesterol in the untreated diabetic rats significantly improved by 160.0, 89.8 and 178.7% respectively in Group 3, 4 and 5 animals. The pancreas and kidney histopathologies indicated signs of recovery in Group 5 rats unlike those of Group 2 that had evidence of necrotic cells in both the acini and islet in pancreas and total glomeruli erosion in kidney. Conclusion: Aloe vera in combination with Metformin for treatment of diabetic patients could avert diabetes-associated dyslipidaemia, improve cellular integrity and increase, thereby preventing patients from risk of cardiovascular diseases and kidney failure
  • Thumbnail Image
    Item
    Anti-obesity, Antioxidant and In Silico Evaluation of Justicia carnea Bioactive Compounds as Potential Inhibitors of an Enzyme Linked with Obesity: Insights from Kinetics, Semi-empirical Quantum Mechanics and Molecular Docking Analysis
    (ELSEVIER Biophysical Chemistry, 2021) Avwioroko, Oghenetega
    Obesity is a global health problem characterized by excessive fat deposition in adipose tissues and can be managed by targeting pancreatic lipase (PL) activity. In the present study, we investigated the in vitro antioxidant and anti-obesity potentials of methanolic leaf extract of Justicia carnea(MEJC) using lipase inhibition kinetics model. In silico evaluations of MEJC bioactive compounds as potential drug-like agents and inhibitors of PL were also investigated using SwissADME prediction tool, semi empirical quantum mechanics(SQM), molecular electrostatic potential(MEP) and molecular docking analysis. Gas chromatography-mass spectrometry (GC–MS) revealed presence of campesterol, stigmasterol, beta-amyrin etc. MEJC scavenged reactive species and inhibited PL activity via a mixed inhibition pattern (Ki = 107.69 μg/mL; Kii = 398.00 μg/mL) with IC50 > orlistat’s IC50. Molecular docking of GC–MS identified compounds with porcine PL showed compounds 8,10,12 and 14 having high PL binding affinity and similar binding pose with orlistat. Hydrophobic interactions and van der Waals forces were predominantly involved in the ligands’ interactions with some key catalytic site amino acid residues (Ser-153,His-264). Compounds 10,12,13 and 14 indicated high drug-likeness, bioavailability, electronegativity, ELUMO-EHOMO energy gaps and MEP. Our findings show that MEJC is a rich natural source of antioxidant and anti-obesity agents which could be optimized for development of new anti obesity drugs.
  • Thumbnail Image
    Item
    Bioactive Components of Ficus exasperata, Moringa oleifera and Jatropha tanjorensis Leaf Extracts and Evaluation of their Antioxidant Properties
    (EurAsian Journal of BioSciences, 2019) Avwioroko, Oghenetega
    Purpose: This study investigated the phytochemistry and in vitro free radical scavenging activities of aqueous leaf extract of Ficus exasperata (FE), Moringa oleifera (MO) and Jatropha tanjorensis (JT). Methods: Spectrophotometric evaluation was employed in the determination of the total phenols, total flavonoids, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition, nitric oxide (NO●) radical inhibition, ferric reducing antioxidant power (FRAP) and total antioxidant capacity (TAOC). Results: Qualitative screening of bioactive compounds confirmed the presence of terpenes, flavonoids and phenols in all extracts amidst other phytochemicals. Total phenols and total flavonoids estimation were highest in Ficus exasperata (96.10 ± 2.70 mg gallic acid equivalent g-1 and 28.45 ± 1.80 mg catechin equivalent g-1, respectively). Moringa oleifera leaf extract exhibited the highest radical scavenging activity against DPPH and NO● radicals, while Jatropha tanjorensis exhibited the highest FRAP and TAOC. Nitric oxide radical inhibition by M. oleifera extract was significantly higher (p<0.05) at 7.0 mg mL-1 (64.7 ± 0.32%). The 50% inhibitory concentration (IC50) values of the plant leaves for FRAP and TAOC were in the order JT < MO < FE, whereas for DPPH and NO● scavenging activities the IC50 values were in the order MO < JT < FE. Conclusions: The findings of this study clearly showed that the antioxidant properties of M. oleifera and J. tanjorensis leaves were higher than those of F. exasperata. The knowledge of the different bioactive components and antioxidant prowess of these medicinal plants could be used as a guide in making the choice of medicinal plant to use for treatment or prophylaxis against cellular aberrations in which oxidative stress is implicated.
  • Thumbnail Image
    Item
    Biochemical Characterization of Crude α-Amylase of Aspergillus spp. Associated with the Spoilage of Cassava (Manihot esculenta) Tubers and Processed Products in Nigeria
    (Advances in Biochemistry, 2015-02) Avwioroko, Oghenetega
    In this research, crude α-amylases associated with the spoilage of cassava (Manihot esculenta) tubers/ product (‘eba’) were biochemically characterized. They were isolated from five fungi: Aspergillus sp. CSA25, Aspergillus sp. CSA26, Aspergillus sp. CSA27, Aspergillus sp. CSA35 and Aspergillus sp. CSA38. The results of the analyses showed that the activities of α-amylase obtained from both sources (cassava tuber/ eba) were optimal at 45°C and pH 5.0. The maximum specific activity (Vmax) of the enzyme was found to be 10 U/mg protein, while its Michaelis-Menten constant (Km) was between 0.37 -1.25%w/v. The α-amylase is thermally stable for 1 - 2 h at optimum temperature and pH (45°C; pH 5.0). A broad range of substrate specificity was expressed by the enzyme for cassava starch-containing products (tapioca flour, garri flour, cassava flour, 1%, w/v); however, potato (Ipomoea batatas) starch, yam (Dioscorea rotundata) flour and cocoyam (Colocasia esculenta) flour were relatively minimally hydrolyzed by the crude α-amylases obtained from Aspergillus spp. that caused spoilage of cassava. Ethylenediamine tetraacetic acid (1 mM EDTA) and Mg2+ treatment had no significant (p > 0.05) effect on the activities of the amylase, but Na+, K+, Ca2+, Fe3+, thiourea and 5′,5′-dithiobis-2-nitrobenzoate (1 mM DTNB) enhanced its activities. The fungal α-amylases were most activated by K+ and had a salt tolerance of 1 - 2 M NaCl for 24 h. The fungal α-amylases reported in this study would find useful application in industries like food industry, detergent industry, paper industry, textile industry, pharmaceutical industry, etc where microbial α-amylases would be required for efficient and cost-effective hydrolysis of cassava starch, cassava flour and or its products.
  • Thumbnail Image
    Item
    Biotechnological Application of Cassava-Degrading Fungal (CDF) Amylase in Broiler Feed Formulation
    (2016) Avwioroko, Oghenetega
    In this study, an attempt was made to substitute maize (Zea mays L.) content of broiler starter feed with ground cassava (Manihot esculenta Crantz) peels enzymatically improved with amylase producing fungi with a view to having a cost-effective yet nutritious and health-friendly feed. The biochemical components of the formulated feeds were determined as well as the effect of the feeds on some biochemical parameters in the broiler chicks. Six starter feeds tagged Control Feed, 20%CPFG, 40%CPFG, 60%CPFG, 80%CPFG and 100%CPFG were formulated with respect to variations in maize and cassava peel contents. The results showed a significant (p70 mgCE/g of feed) and most of them comparatively high in anthocyanin relative to the control feed anthocyanin content (225.4±12.2 mg/g of feed). The highest weight gain (108.0±3.0 g) was observed in broiler chicks fed the feed ration containing 60% cassava peels improved with amylase-producing fungi and 40% maize (60%CPFG). Broiler chicks fed the formulated feeds, including the control, exhibited over 40% inhibition against 2, 2-diphenyl-1- picrylhydrazyl (DPPH) radical. The serum activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in birds fed the compounded feeds and control slightly differed except in group 60%CPFG. It was concluded that the maize content in broiler feed can be replaced with cassava peels improved with fungal amylase upto a maximum of 60%. This would significantly decrease the overall cost of broiler feed production without compromising the nutritional, antioxidant and health-friendly potentials of the feed.
  • Thumbnail Image
    Item
    Brillantasia patula Aqueous Leaf Extract Averts Hyperglycermia, Lipid Peroxidation, and Alterations in Hematological Parameters in Alloxan-Induced Diabetic Rats
    (International Journal of Biomedical Science and Engineering, 2018) Avwioroko, Oghenetega
    The protective effects of aqueous leaf extract of Brillantasia patula against hyperglycermia, lipid peroxidation, and alterations in hematological parameters in diabetic Wistar rats were investigated. The study consisted of six treatment groups, with five animals each, designated as Group-1 (healthy), Group-2 (diabetic control) and Groups 3-6 (diabetic rats treated with 500, 1000, 1500, and 2000 mg/kgbwt of extract, respectively). Rats were administered their respective doses orally, and daily, for 14 days. Thereafter, the effects on serum glucose levels, liver and kidney functions, lipid peroxidation, free radical scavenger and hematological parameters were analyzed. Blood glucose levels reduced markedly in diabetic rats given the plant extract relative to diabetic control. Both serum creatinine and urea decreased significantly in treated diabetic rats at extract doses of 1000 mg/kgbwt and above. Reductions in serum cholesterol (p<0.05) and triglyceride levels (p<0.05) were also observed. Elevated total serum protein and globulin in diabetic control was decreased in all treated groups. Haematological indices of groups given the extract were noticeably enhanced. Similarly, kidney, heart and liver glutathione (GSH) levels increased significantly in groups treated compared to diabetic control; lipid peroxidation in kidney and heart also decreased significantly in all the treated groups. Liver catalase activity improved. Serum alanine and aspartate aminotransferases activities widely lowered in Groups 3 and 4. The study indicates that Brillantaisia patula aqueous leaf extract exhibits potential hypoglycemic effect, prevents lipid peroxidation, boosts haematological parameters, and could protect liver and renal damage associated with diabetes especially at doses of 500 - 1000 mg/kgbwt.
  • Thumbnail Image
    Item
    Characterization of a Surfactant-stable α-amylase Produced by Solid State Fermentation of Cassava (Manihot esculenta Crantz) Tubers Using Rhizopus oligosporus: Kinetics, Thermal Inactivation Thermodynamics and Potential Application in Laundry Industries
    (ELSEVIER Biocatalysis and Agricultural Biotechnology, 2022) Avwioroko, Oghenetega
    α-Amylase is a foremost hydrolytic enzyme used for various industrial processes. In the present study, Rhizopus oligosporus α-amylase (ROAA) produced during solid state fermentation of cassava (Manihot esculenta) tubers by the fungus was partially purified and biochemically characterized. The kinetic and thermal inactivation thermodynamics properties of the partially purified enzyme were also evaluated as well as the potential application in cloth washing. The ROAA was purified by 4.11-fold and had a molecular weight of 60 kDa. ROAA was optimally active at 60 ◦C, pH 5.0 and had a salt tolerance of 1–100 mM NaCl for 120 min. The activity of the α-amylase was significantly (p < 0.05) increased in the presence of various inorganic salts especially at 10 mM. Ethylenediaminetetraacetic acid (EDTA), urea and thiourea enhanced ROAA activity. Triton X100 enhanced ROAA activity by 141.97%, whereas sodium dodecyl sulphate (SDS) decreased it by 28.58%. Tween 20 and Tween 80 did not significantly affect ROAA activity at 1 mM. Vmax, Km and Kcat of ROAA were 37.59 U/mg protein, 16.39 mg/mL and 0.016 s − 1 , respectively. Thermal stability indicators such as half-life, D-value at 70 ◦C and Z-value were 101.91 min, 338.70 min, and 48.78◦C, respectively. Cloth washing efficiency of a mixture of the isolated enzyme and commercial detergents was high relative to detergent-only trial. The enzyme had high thermal stability, optimized activity in the presence of some inorganic salts, and resistance to several surfactants and a chelating agent. The fungal α-amylase reported in this study would find relevance not only in starch-based industries but also in laundry.
  • Thumbnail Image
    Item
    Characterization of α-amylases Isolated from Cyperus esculentus Seeds (tigernut): Biochemical Features, Kinetics and Thermal Inactivation Thermodynamics
    (ELSEVIER Biocatalysis and Agricultural Biotechnology, 2019) Avwioroko, Oghenetega
    In this study, α-amylases from fresh and dried Cyperus esculentus seeds were isolated and characterized for biochemical and thermodynamic properties. The α-amylases (FTNE-α-amylase and DTNE-α-amylase) were optimally active at 60–70 oC, pH 7.0 (FTNE-α-amylase) and pH 6.0 (DTNE-α amylase) with activation energies (Ea) of 3.56 and 6.81 kJ mol-1, respectively. Both enzymes retained above 70% of their hydrolytic activities after 1 h at pH 6.0–8.0. The enzyme activities were more enhanced in the presence of divalent metal ions (Ca2+, Mg2+, Zn2+, Cu2+, Ba 2+, Co2+, Pb2+, and Hg2+) than monovalent ions. SDS, cyclohexanol, ether and diethylamine inhibited them except EDTA. Using soluble starch as substrate, DTNE-α-amylase had higher Vmax, Kcat and lower Km than FTNE-α-amylase. Both enzymes expressed high substrate preferences for yam flour amidst other substrates with catalytic efficiencies (Kcat/Km) of 2.71 and 4.44 mL. mg respectively. The higher catalytic efficiency of DTNE-α amylase was due to its transition state stabilization (ΔGE-S ¼ -0.90 kJ mol-1 and ΔGE-T ¼ - 2.22 kJ mol-1). Fourier Transformed-Infrared (FTIR) spectroscopy revealed changes in C–O stretching and -N-H bending in the substrate-bound enzymes. Thermal inactivation of the amylases followed first-order rate kinetics and was non-spontaneous (ΔG#>0). FTNE-α-amylase half-lives and D-values at 70 and 80 oC, and Z-value (256.41oC), were however higher than in DTNE-α-amylase (Z-value ¼ 63.29 oC; t1/2 ¼ 22.43 min at 70oC) indicating that FTNE-α-amylase is more thermally stable than DTNE-α-amylase and would be more industrially applicable as a thermostable starch-hydrolyzing enzyme.
  • Thumbnail Image
    Item
    Chemical Profile, Antioxidant and Alpha-Amylase Inhibitory Activity of Leaves Extracts of Annona muricata: A Combined In vitro and In silico Study
    (Letters in Applied NanoBioScience, 2022) Avwioroko, Oghenetega
    Leaves of Annona muricata are commonly used for treating diabetes. This study was conducted to investigate the molecular mechanisms involved in the antidiabetic properties of leaves of Annona muricata. Leaves of Annona muricata were extracted separately with H2O, hydromethanol (50% methanol), methanol, ethylacetate, and n-butanol. Chemical characterization of the extracts was performed by spectrophotometry and Gas chromatography-Mass Spectrometry (GC-MS) techniques. Biological activity was determined by α-amylase inhibition assays and molecular docking. The hydromethanol extract had a total phenolics concentration of 117.00±0.59 µg GAE/mg extract whereas; flavonoids were most abundant in the n-butanol extract accounting for 29.34±8.87 µg QE/mg extract. The n-butanol extract had the best FRAP value of 41.17±0.57 Vit C eqv mM, which was significantly higher than the value of the vitamin C reference. Estimated IC50 for all the extracts did not differ significantly but was significantly higher than the reference compound quercetin. All extracts inhibited α-amylase in vitro albeit significantly lower than acarbose. The hydromethanol extract had the highest inhibitory activity (53.31 ± 0.33%). Furthermore, chemical profiling of the hydromethanol extract revealed the presence of a variety of bioactive compounds. In silico analysis by molecular docking of the compounds identified by GC-MS on α-amylase revealed that the compounds had robust molecular interactions orchestrated by H-bonding and hydrophobic interactions. From the results, it can be concluded that extracts of Annona muricata possess antioxidant phytochemicals that inhibit α-amylase. Therefore, the results justify the use of the plant for the treatment of diabetes.
  • Thumbnail Image
    Item
    Comparative Biochemical Evaluation of the Proximate, Mineral, and Phytochemical Constituents of Xylopia aethiopica Whole Fruit, Seed, and Pericarp
    (Preventive Nutrition and Food Science, 2021) Avwioroko, Oghenetega
    This study evaluated the relative abundance of proximate, mineral, and phytochemical constituents of the anatomical parts of Xylopia aethiopica (XA) fruit using standard analytical procedures. The results showed that whole fruits (WF) have higher contents of crude protein, crude fiber, fat, ash, and moisture than the seeds (S) and pericarps (P). However, highest contents of crude carbohydrate and nitrogen free extracts were found in the P, followed by the S. The content of minerals (sodium, potassium, calcium, phosphorus, iron, zinc, magnesium, and copper) and phytochemicals were present in the following order of abundance: WF>S>P. Furthermore, the phytochemical constituents in each XA parts were present in the following order of relative abundance: total flavonoids>tannins>total phenolics>cardiac glycoside>alkaloids>steroids. Vitamin A was abundant in all three parts, with the abundance highest in WF [4.83±0.06 g vitamin A equivalent (vit A eq)/100 g] and lowest in P (1.64±0.02 g vit A eq/100 g). This preliminary study indicates XA fruits are rich in minerals, anti-nutrients, and phytochemicals. Therefore, these data could represent a biochemical rationale for inclusion of XA as a spice or functional ingredient in many Nigerian local soups to help prevent ailments
  • Thumbnail Image
    Item
    Comparative Study of the Effects of Annona muricata and Tapinanthus globiferus Extracts on Biochemical Indices of Diabetic Rats
    (Pharmacognosy Journal, 2019) Avwioroko, Oghenetega
    Introduction: Annona muricata and Tapinanthus globiferus (mistletoe) are medicinal plants used in traditional medicine to combat an array of human diseases. However, there is dearth of scientific prove for the activity of these plants in the management of non-infectious human diseases such as cancer, insomnia, hypertension, ulcers and diabetes. Method: The present study was designed to assess comparatively the effects of methanol extracts of Annona muricata (AME) and Tapinanthus globiferus (TGE) on biochemical indices of alloxan induced diabetic rats. The animals were allocated to eight (8) groups, group I were normal non-diabetic rats, group II (diabetic untreated group), group III treated with metformin alone, groups IV & V were diabetic rats treated with AME at dose of concentration 200 mg/kg BW & 400 mg/kg BW respectively, groups VI & VII were diabetic rats treated with 200 mg/kg BW & 400 mg/kg BW of TGE respectively. Group VIII were diabetic rats treated with AME + TGE at concentration of 200 mg/kg BW each. Concentrations of serum total cholesterol (TC), high density lipoprotein (HDL), triglyceride (TG) of alloxan diabetic rats, creatinine and urea were assayed after 21 days of the respective treatments. Results: Diabetic untreated rats had significant increase p<0.05 in TC, TG, urea and creatinine compared to normal control group as opposed to the significant decrease observed for HDL in diabetic rats. However, treatment of diabetic rats with AME and TGE significantly suppressed (p<0.05) the concentrations of TC, TG and creatinine when compared with the diabetic untreated rats. A similar trend was observed for the calculated atherogenic index of treated rats when compared with diabetic untreated rats. Interestingly, co-administration of AME + TGE improved the biochemical indices of diabetic rats better than using each plant separately. Conclusion: The results of this study suggest that AME and TGE could offer some benefits in the management of diabetic complications especially with regard to cardiac and renal health.
  • Thumbnail Image
    Item
    Diverse Applications of Biotechnology
    (Academic Journals, 2010) Avwioroko, Oghenetega
    The exciting discipline of biotechnology has drawn the interests of traditional biologists, biochemists, microbiologists, medical and agricultural scientists into applying mathematical and engineering models to understanding biology. Also, the biopharmaceutical, biochemical and agricultural industries are rapidly drawing from and applying the research results of biotechnology. Still, new industries relying on genomics are springing up daily to challenge the way things have been done.
  • Thumbnail Image
    Item
    Effect of Fermentation on Sensory, Nutritional and Antioxidant Properties of Mixtures of Aqueous Extracts of Hibiscus Sabdariffa (Zobo) and Raphia Hookeri (Raffia) Wine
    (Nigerian Journal of Science and Environment, 2017) Avwioroko, Oghenetega
    This study investigated the effect of fermentation on the nutritional, antioxidant and sensory properties of aqueous extracts of Hibiscus sabdariffa (popularly called Zobo in Nigeria) and Raphia hookeri (raffia) wine mixed in various proportions: P100 - Z0, P80 -Z20, P60 -Z40, P40 -Z60, P20 -Z80 and P0 -Z100. Glucose, soluble protein, vitamin C content, antioxidant activity and sensory properties (colour and taste) were evaluated in fresh mixture preparations, and in formulations fermented at room temperature for 72 h (day 3). Glucose was depleted significantly (p < 0.05) as fermentation progressed, the order of decrease was: P100 - Z0 (97.59%) > P80 -Z20 (95.90%) > P60 - Z40 (95.17%) > P0 - Z100 (90.94%) >P20 -Z80 (71.30%) > P40 -Z60 (66.42%). Soluble protein concentration also decreased with fermentation, the highest and lowest % decrease was observed for the P100 - Z0 (25.97%) and P60 - Z40 (5.35%) respectively. The highest DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging activity was detected in the P80 - Z20 (72.20%) mix. Sensory evaluations confirmed the best combination was the P80-Z20 raffia wine/zobo extract mixture, this maintained an appealing red colour, sweetness of palm wine and the contributory antioxidant properties from zobo extracts optimized.
  • Thumbnail Image
    Item
    Effect of Preservation on the Chlorophyll Content, Phytochemicals, And Antioxidant Capacity of Two Different Varieties of Pumpkin (Telfairia occidentalis) Leaves
    (Nigerian Journal of Technological Research, 2015-03) Avwioroko, Oghenetega
    The aim of the present study was to investigate the effect of two preservation techniques (refrigeration and freezing) on the chlorophyll content, phytochemicals, and antioxidant capacity of two different varieties of pumpkin (Telfairia occidentalis) leaves over a period of two weeks. The biochemical parameters assessed include chlorophyll content, total soluble protein, reducing sugar, total phenolics, total flavonoids and ferric reducing antioxidant power (FRAP). The results of the study show that in both broad and slender leaves pumpkin varieties investigated, refrigeration and freezing for two weeks led to a significant decrease (p<0.05) in their chlorophyll contents. Total chlorophyll a and b content in the preserved broad leaf pumpkin variety (BLP) decreased by an average of 49.12%, whereas the average percentage decrease in total chlorophyll a and b observed in the preserved slender leaf variety (SLP) was 79.01% compared to their respective fresh leaves controls. Refrigeration and freezing for two weeks also resulted in a significant decrease (p<0.05) in total soluble protein and reducing sugar contents of both broad leaf (BLP) and slender leaf (SLP) varieties of pumpkin. However, the preservative methods did not significantly (p>0.05) affect the level of phenolics in the broad leaf pumpkin variety, although it was significantly decreased in the slender leaf pumpkin variety preserved by refrigeration. There was no significant difference (p>0.05) in flavonoid contents among the refrigerated, frozen and fresh leaves of the broad pumpkin leaf variety (BLP). However, the preserved slender pumpkin leaves variety (SLP) again suffered a significant decrease. Though the ferric reducing antioxidant power (FRAP) of broad leaf pumpkin variety (BLP) preserved by refrigeration (4°C) and freezing (- 20°C) were slightly decreased by 20.9% and 16.1%, respectively, compared to their fresh broad leaf control, the decrease was not significant (p>0.05). On the contrary, the FRAP of the preserved slender leaf pumpkin variety (SLP) was significantly decreased (p<0.05) relative to their fresh slender leaf control. It could be inferred from the findings of this research that the broad leaf pumpkin variety (BLP) can be preserved by freezing (temperature -20°C) for a period of two weeks without any significant (p>0.05) loss of its valuable phytochemicals and antioxidant capacity compared to the slender leaf pumpkin variety.
  • Thumbnail Image
    Item
    Effect of Preservation on Two Different Varieties of Vernonia amygdalina Del. (Bitter) Leaves
    (Food and Nutrition Sciences, 2015-01) Avwioroko, Oghenetega
    Vernonia amygdalina Del. is one of the leafy vegetables that can be used in an attempt to alleviate the problem of micronutrient malnutrition, prominent in tropical Africa. In order to ensure availability in non-growing areas or seasons, the vegetable needs to be preserved. Processing and preservation methods influence the nutrient content of vegetables. The present study was aimed at determining the effects of preservation on two different varieties of V. amygdalina (bitter) leaves (broad and small leaves). To this effect, evaluations were made on the chlorophyll content, phytochemicals, and antioxidant capacity of the two varieties of bitter leaf (V. amygdalina Del.) stored at 4˚C and −20˚C over a period of two weeks. Results showed a significant decrease in all parameters studied for both varieties at −20˚C except for the free radical reducing power (FRAP), DPPH radical scavenging activity (%RSA) and nitric oxide radical scavenging activity (%RSA) of V. amygdalina broad leaves where increase in scavenging activity was observed. Thus, it was concluded that to preserve the chlorophyll, phenol, total soluble proteins and reducing sugar levels, preservation at 4˚C is recommended. The present study finding would be useful during short-term preservation of bitter leaves for soup preparation and/or its aqueous extract for ethnomedicinal purposes, especially the small leaf variety.
  • Thumbnail Image
    Item
    Effect of Supplementation of Animal Feed with Dried Cassava (Manihot esculenta) Peels, and Stems of Vernonia amygdalina and Pennisetum purpereum on Some Biochemical Parameters in Pigs
    (Nigerian Society for Experimental Biology, 2014) Avwioroko, Oghenetega
    This study examined the effects of pig feed supplementation with dried cassava peels, Vernonia amygdalina and Pennisetum purpereum stems, which are readily available, on pigs’ body weights and some biochemical parameters. Twelve large White x Dunroc weaner pigs with an average body weight of 5.85±0.70 kg were used for the study. The pigs were randomly divided into 4 treatment groups and were fed with formulated experimental diet twice daily for 21 days. In addition, pigs in groups 2, 3 and 4 received dried V. amygdalina stems, cassava peels, and P. purpureum stems ad libitum, respectively, as food supplement in the afternoon daily. At the end of the feeding trial, the animals were weighed and bled. Serum obtained from the blood samples was used for biochemical analysis. Pigs fed only the formulated diet had the lowest weight gain (0.47±0.29 kg) while those that received cassava peels as food supplement had the highest weight gain (1.67±0.82 kg). There was no significant difference (P>0.05) in serum creatinine, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values in the pigs, but serum glucose, cholesterol, albumin, calcium, urea and urea nitrogen differed significantly (P<0.05) among the experimental groups. The results indicate that pig feed supplementation using dried cassava peels, V. amygdalina and P. purpereum stems can provide growing pigs with additional nutrients. They also show that pig feed supplementation with dried cassava peels, V. amygdalina stem and P. purpereum can increase the weight of growing pigs on the short term without any toxic effects to the liver and kidney.
  • Thumbnail Image
    Item
    Evaluation of Chemical Composition, in vitro Antioxidant, and Antidiabetic Activities of Solvent Extracts of Irvingia gabonensis Leaves
    (Heliyon, 2022) Avwioroko, Oghenetega
    Irvingia gabonensis commonly referred to as wild mango or ogbono is a tropical plant with both nutritional and medicinal uses. The present study was designed to evaluate the chemical composition, in vitro antioxidant activity, and inhibitory activity of carbohydrate hydrolyzing enzymes related to diabetes by different extracts of the plant. From the results of the study, Total Phenolic Content (TPC) was highest in the aqueous and ethanol extracts (367.30 00 mg/100g GAE) compared to the chloroform and n-hexane extracts whereas the Total Flavonoid Content (TFC) was highest (230.69 0.18 mg/100g QE) in the ethanol extract. Analysis of the in vitro antioxidant activity showed that the ethanol extract also possessed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (IC50: 21.42 0.05 μg/ml) and hydroxyl radical scavenging activity (81.43 0.11%) compared to other solvent extracts. The aqueous extract had the highest (23.91 0.04 mM Feþþ equivalent) ferric antioxidant reducing power (FRAP). However, the antioxidant activity of the extracts was significantly lower than that of the reference compounds used for the study (butylated hydroxytoluene and Gallic acid). In vitro antidiabetic activity of the ex tracts was measured based on inhibition of α-amylase and α-glucosidase. The aqueous extract had the highest α-amylase and α-glucosidase inhibitory activity followed by the ethanol extract compared to the chloroform and n hexane extracts. The inhibitory activity of the aqueous extract against both enzymes was higher compared to the reference compound Acarbose. Gas Chromatography-Mass Spectrometry analysis of the extracts revealed the presence of chemical constituents including fatty acids, vitamin, phytosterols, aromatic compounds, glycosides. The interaction of these compounds with α-amylase and α-glucosidase was evaluated in silico by molecular docking. Phytosterols namely, campesterol, stimasterol and γ-sitosterol had the best binding affinities to α-amylase and α-glucosidase. In conclusion, the results of this study revealed that the aqueous and ethanol extracts of Irvingia gabonensis had the highest phenolic content, antioxidant activity, and in vitro antidiabetic activity. These results offer a scientific explanation for the mode of preparation and traditional use of the plant in the treatment of diabetes
  • Thumbnail Image
    Item
    Exploring the Binding Interactions of Structurally Diverse dichalcogenoimidodiphosphinate Ligands with α-amylase: Spectroscopic Approach Coupled with Molecular Docking
    (ELSEVIER Biochemistry and Biophysics Reports, 2020) Avwioroko, Oghenetega
    Postprandial hyperglycemia has orchestrated untimely death among diabetic patients over the decades and regulation of α-amylase activity is now becoming a promising management option for type 2 diabetes. The present study investigated the binding interactions of three structurally diverse dichalcogenoimidodiphosphinate ligands with α-amylase to ascertain the affinity of the ligands for α amylase using spectroscopic and molecular docking methods. The ligands were characterized using 1 H and 31P NMR spectroscopy and CHN analysis. Diselenoimidodiphosphinate ligand (DY300), dithioimidodiphosphinate ligand (DY301), and thioselenoimidodiphosphinate ligand (DY302) quenched the intrinsic fluorescence intensity of α-amylase via a static quenching mechanism with bimolecular quenching constant (Kq) values in the order of x1011 M-1s -1, indicating formation of enzyme-ligand complexes. A binding stoichiometry of n≈1 was observed for α-amylase, with high binding constants (Ka). α-Amylase inhibition was as follow: Acarbose > DY301>DY300>DY302. Values of thermodynamic parameters obtained at temperatures investigated (298, 304 and 310 K) revealed spontaneous complex formation (ΔG<0) between the ligands and α-amylase; the main driving forces were hydrophobic interactions (with DY300, DY301, except DY302). UV–visible spectroscopy and Forster ¨ resonance energy transfer (FRET) affirmed change in enzyme conformation and binding occurrence. Molecular docking revealed ligands interaction with α-amylase via some key catalytic site amino acid residues (Asp197, Glu233 and Asp300). DY301 perhaps showed highest α-amylase inhibition (IC50, 268.11 ± 0.74 μM) due to its moderately high affinity and composition of two sulphide bonds unlike the others. This study might provide theoretical basis for development of novel α-amylase inhibitors from dichalcogenoimidodiphosphinate ligands for management of postprandial hyperglycemia