Physicochemical composition and antioxidant properties of a sweetpotato variety (Ipomoea batatas L) commercially sold in South Eastern Nigeria

The physicochemical composition, functional properties, inhibitory actions and energy value of the flour of a cream fleshed sweetpotato variety (TIS/87/0087) that is high yielding and commercially sold in South Eastern Nigeria were investigated using standard techniques. The flour was observed to have good functional properties with a pH of 5.32±0.01, high percentage moisture content, indicative of poor shelf life characteristics and high chances of being attacked by microbes, low percentage dry matter, lipid, crude fibre and ash contents but a promising source of starch (20.78±0.02%), carotene (5.0±0.04 μg/g), protein (2.67±0.59%), carbohydrate (40.77±3.05%), energy (179.61±20.97 kcal/100 g), polyphenols, in addition to containing significant quantities of reducing sugar (1.58±0.53%). In addition, the methanolic extract of the flour possessed higher scavenging activities on 2,2 diphenyl-1-picrylhydrazyl (DPPH) radical than standard quercetin. Results show that this sweet potato variety has potentials of biological properties and could have wide utility in food, alcohol and sugar industries. In addition, it could serve as a promising source of protein and its consumption could be utilized in the management of diseases that implicate free radicals. Finally, it could also be useful as a drug binder and disintegrant in pharmaceutical industries.Keywords: Sweetpotato flour, functional property, physicochemical, foodsAfrican Journal of Biotechnology Vol. 12(7), pp. 720-72

Comparative evaluation of the physicochemical composition and microbial quality of seven different water sources used in processing root and tuber crops in Umudike, Nigeria

The physicochemical composition and microbial quality of 7 different water sources (Umudike ukwu bore hole (B5), Umuariaga borehole (B3), Nidoro spring water (S2), Umudike bore hole (B4), Umudike school borehole A (B7), Umudike school bore hole B (B6) and Ahiaeke bore hole (B9) used for root and tuber crop processing in Umudike, Nigeria were investigated using standard techniques. The chloride, sulphate, phosphate, dissolved substances, hardness of water, ammonium nitrate and conductivity in all the water samples, fell within the range recommended by the Nigerian Industrial Standard (NIS) or the World Health Organization (WHO) while the values obtained for pH and nitrites were lower than the range given by WHO and NIS. Most of the samples had higher organic carbon contents than permitted. In terms of dissolved oxygen (D) and total hydrogen (TH), S2 had the highest, B5 and B6 had the least for DO (P > 0.05) while B6 had the least in addition for TH. The biochemical oxygen demand (BOD) of B3 was the highest among the water samples analyzed (P < 0.05) while that of B5 and B6 were the least (P > 0.05). Sensory evaluation of the samples showed that they were clear, tasteless and odorless. Microbial analysis carried out indicated the presence of coliforms in the water samples although this does not give any cause for concern as they fell within the standards for coliform in water. The total plate count of the samples ranged from 8.00 to 19.09cfu/100ml with B9 having the highest while B7 had the least. Some of the microorganisms isolated include: E.coli, salmonella, shigella, fungi and staphylococcus, indicating microbial contamination of these water samples and thus highlights the need for their urgent sterilization. The absence of Vibrio cholerea in all the water samples indicate the non-prevalence of cholera in the study area. Finally, most of the water sources used by these communities in processing their root and tuber crops did not meet the recommended standards for nitrites, biochemical oxygen demand, organic carbon and nitrites in water, underscoring the need for regular checks and on these water sources.Key words: Water, microbial, coliform, physicochemical, root crops, tuber crops

Ameliorative Potentials of Cocoyam (Colocasia esculenta L.) and Unripe Plantain (Musa paradisiaca L.) on the Relative Tissue Weights of Streptozotocin-Induced Diabetic Rats

Aim. To investigate the ameliorating potentials of cocoyam (Colocasia esculenta L.) and unripe plantain (Musa paradisiaca L.) incorporated feeds on the renal and liver growths of diabetic rats, induced with 55 and 65 mg/kg body weight of Streptozotocin. Method. The blood glucose level of the rats was measured with a glucometer, the protein and glucose and specific gravity (SPGR) in the urine samples of the rats were measured using urine assay strips and urinometer respectively. The chemical composition and antioxidant screening of the test feeds were carried out using standard techniques. Results. Administration of the test feeds for 21 days to the diabetic rats of groups 4 and 5, resulted in 58.75% and 38.13% decreases in hyperglycemia and amelioration of their elevated urinary protein, glucose, SPGR, and relative kidney weights. The diabetic rats administered cocoyam incorporated feeds, had 2.71% and 19.52% increases in weight and growth rates, the diabetic rats administered unripe plantain incorporated feeds had 5.12% and 29.52% decreases in weight and growth rates while the diabetic control rats had 28.69%, 29.46%, 248.9% and 250.14% decreases in weights and growth rates. The cocoyam incorporated feeds contained higher antioxidants, minerals and phytochemicals except alkaloids than unripe plantain feed. Conclusion. Cocoyam and unripe plantain could be useful in the management of diabetic nephropathy