Antioxidant activity (AOA) and phytochemical content of Moringa oleifera Lam leaves were determined as a function of their age and extraction solvent. Fresh Moringa leaves aged 30, 45, and 60 days were harvested and extracted with three solvents; methanol, ethanol, and water. AOA of leaf extracts was measured using radical scavenging assays (DPPH, ABTS, antiperoxide activity [APA]) and reducing assays (FRAP and total antioxidant capacity [TAC]), and these were correlated with total polyphenols (TPC), total flavonoids (TFC), and chlorophyll contents of leaves. Significant variability (p < 0.05) in TPC and AOA of Moringa leaf extracts was observed with age and extraction solvent as well as their interaction. TPC and TFC increased with maturity, except in aqueous extract. The 60‐day‐old leaves showed highest TPC, TFC, and tocopherol contents with highest DPPH activity. On their part, 30‐day‐old leaves recorded better vitamin C, chlorophyll, and carotenoids with highest ABTS activity and APA. Methanol was best extraction solvent for TPC (4.6 g GAE/100 g DM) while ethanol was for flavonoids (1.8 g CE/100 g DM). Ethanol extracts exhibited the highest DPPH activity (53.3%–71.1%), while both ethanolic and methanolic extracts had similar and higher ABTS + activity (3.83–3.86 g AAE/100 g DM). Strong positive correlations (r ≥ 0.8; p < 0.05) were observed between chlorophyll content and DPPH, ABTS, and APA, suggesting that chlorophyll was the major contributor to AOA. TAC was highest in aqueous solvent. Free radical scavenging activity in Moringa leaves is positively correlated to chlorophyll, TFC, and TPC while reducing power is positively correlated to chlorophyll and TPC. AOA of fresh Moringa leaf extract is a function of its phytochemical content and is influenced by both the age of the leaves and the extraction solvent used. Methanolic and ethanolic extracts of 45‐day‐old Moringa leaves exhibited best antioxidant potentials.

This work reviews treatments and uses of Moringa oleifera seeds in human nutrition. Moringa oleifera seeds are considerable sources of proteins (mean 19%) and lipids (mean 31%). Previous reports presented the nutritional properties of the seeds and oil. Moringa seeds are sources of lipids, and their removal leads to Moringa seed flour with a high protein content which might play a role in food technology and human nutrition. Moringa oil has been tested in frying and was found to be more stable than groundnut oil; its incorporation in groundnut at level lower than 10% improved on the acceptability of chips. Several treatments like roasting, germination, and boiling have been applied to Moringa seeds to produce flour with improved nutritional properties. In particular, defatted Moringa flour has been applied in different formulations including cakes, cookies, burgers, infant porridges. Generally, the products deriving from the flour were more stable in conservation and well accepted for low substitution while high substitution increased the bitterness. Notwithstanding their high content in protein and oil, defatted M. oleifera seed flour and oil are still fairly investigated in order to envisage their integration in the food habits of people. The present wrote up reviews the treatments applied on M. oleifera seeds and applications of the defatted M. oleifera flour and oil in food systems for human nutrition.

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Maintenance of glycemic control is important in preventing diabetes and its associated complications. Considering the current recommended approach for the use of functional foods and their bioactive components in the prevention and management of diabetes, the aim of this study was to determine the antihyperglycemic effect of Moringa oleifera functional tea in rat models and in normoglycemic human volunteers using the oral glucose tolerance test (OGTT). Moringa tea prepared by extracting Moringa leaf powder in distilled water (1:20 mg/ml) at 97˚C for 30 min was administered at different doses to male Wistar rats and human volunteers prior to glucose loading. Blood glucose was measured at intervals of 30 min for 150 min. Consumption of Moringa tea prior to glucose loading suppressed the elevation in blood glucose in all cases compared to controls that did not receive the tea initially. The degree and pattern of decrease however, were dose dependent. In rats, intermediate doses of 20 ml/kg BW were more effective in reducing blood glucose overall (18.2%) vs 13.3% and 6% at doses of 10 and 30 ml/kg BW respectively. In humans, the final decrease in blood glucose was not significantly different for high 400 ml (19%) and low 200 ml (17%) doses. Of interest here was the pattern of decrease, being significantly higher (p < 0.05) at 30 min with 200 ml (22.8%) than with 400 ml (17.9%). It is suggested that low doses exert their antihyperglycemic effect more at intestinal level by inhibiting glucose absorption, whereas high doses exert their effect more in circulation. We conclude that Moringa oleifera tea has potential as a functional food in the management of hyperglycemia.

The physicochemical, alveographic and sensory characteristics of precooked taro-wheat composite flours and their biscuits were investigated. A 2x7 factorial design consisting of two varieties of taro flour (Red Ibo Ngaoundere, RIN, and egg-like varieties) and 7 levels of wheat substitutions (0, 5, 10, 15, 20, 25 and 30 %) was used for this purpose. It was observed that water absorption capacity (range 95-152 g/100 g), water solubility index (range 18.8-29.5 g/100 g) and swelling capacity (range 125.4-204.6 mL/ 100 g) of composite flours significantly (p<0.05) increased with increase in taro level. Conversely the dough elasticity index (range 59.8-0 %), extensibility (78-22 mm) and strength (range 281-139×10 −4 joules) significantly (p< 0.05) diminished with increase in wheat substitution. Up to 10 % substitution with RIN taro flour and 15 % with egg-like taro flour, the composite taro-wheat dough exhibited elasticity indices acceptable for the production of baking products, whereas at all levels of taro substitution, the composite biscuits samples were either acceptable as or better (5-10 % substitution with RIN flour) than 100 % wheat biscuit.

This paper examines the risk of Vitamin A deficiency among selected pregnant women in Ngaoundere, Adamawa Region, Cameroon. A total of one hundred (100) pregnant women attending ante natal visits at the Regional Hospital in Ngaoundere were involved in a survey conducted in 2012 which used a 24-hour dietary recall to assess their dietary intake. Food models were used to assist memory and portion sizes of food taken. Carotenoids were quantified in the meals commonly consumed, as well as proteins, sugar, fibers and oil, nutrients intervening in carotenoids absorption and Vitamin A metabolism. The results indicated that the dietary intake of Vitamin A was inadequate with 37.5% of the selected pregnant women exposed to acute Vitamin A deficiency, while 20% of them were exposed to the severe form. The daily consumption of Vitamin A was about 539.09 ± 43.09 µg, corresponding to a contribution of 67.39% to the Vitamin A requirement of the pregnant women. The dietary intake of macronutrients was also inadequate with a daily consumption of 57.28 ± 12 g for oils, 177.88 ± 29 g for sugars, 47.34 ± 11 g for proteins and 11.28 ± 3 g for fibers corresponding respectively to a contribution of 63.6%, 70.8%, 78.90% and 45.1% of these nutrients requirement in these women. Given that over 50% of the women surveyed were exposed to Vitamin A deficiency, there is a need for urgent intervention programs in the area to alleviate this situation.

Optimal conditions for alcoholic extraction of antioxidants from roasted leaves of Moringa oleifera Lam. were determined using response surface methodology and the phenolic profile of optimised extract determined by HPLC‐PDA. The experimental results adequately fitted the second‐order polynomial models as indicated by regression coefficient (.90–.95), lack‐of‐fit >.05, and absolute deviation .01–.04). Using multiple responses optimization and desirability function, the optimal conditions needed to maximize simultaneously antioxidant activity, phenolic content and extract yield were 65%–75% ethanol, 55–65°C and 40 min. The experimental values were not significantly different (p > .05) from those predicted, indicating the suitability of the models in the studied range. HPLC analysis of the extract revealed the presence of quercetin, isoquercetin, caffeic acid, and rutin. Rutin (45 mg/g), a flavonoid, was the major phenolic. The extract exhibited significant antioxidant potential IC50 2,2‐diphenyl‐2‐picryl hydrazyl 1.28 mg/L, ferric reducing antioxidant power 236 mg AAE/g, total phenolic content 176 mg GAE/g and could be used as nutraceuticals. Practical applications Moringa oleifera L. leaves were roasted to improve antioxidant function and optimum conditions for the preparation of extract with optimal antioxidant potential determined using the multiple response optimization procedure. The resulting extract was freeze‐dried and its phenolic profile characterized by HPLC‐PDA. The powdered extract has good antioxidant (radical scavenging and ferric reducing) potential and contained rutin as the major phenolic flavonoid followed by quercetin, isoquercetin caffeic acid, and vanillin. The extract has potential for use in nutraceutical formulations for the prevention and management of oxidative stress and chronic diseases (diabetes, cardiovascular diseases, cancer).