Chemical Composition and Quality Characteristics of Wheat Bread Supplemented with Leafy Vegetable Powders

The study investigated the effect of supplementation of the leaf powders of Telfairia occidentalis, Amaranthus viridis, and Solanum macrocarpon on the chemical composition and the quality characteristics of wheat bread. The bread samples were supplemented with each of the vegetable leaf powders at 1%, 2%, and 3% during preparation. The bread samples were assayed for proximate composition, mineral composition, physical, sensory, and antioxidant properties using standard methods. The addition of vegetable powders significantly increased the protein (9.50 to 13.93%), fibre (1.81 to 4.00%), ash (1.05 to 2.38%), and fat (1.27 to 2.00%). Supplementation with vegetable powder however significantly decreased (p<0.05) the carbohydrate and moisture contents. Significant (p<0.05) increases were recorded for all evaluated minerals as the level of vegetable powder increased. Supplementation with vegetable powder caused significant decrease in total phenolic content, percentage DPPH inhibition, metal chelating ability, ferric reducing antioxidant power, and total antioxidant capacity. Sensory results showed that there was significant decrease in sensory qualities with increasing supplementation. This therefore suggests that bread supplemented with vegetable powder could have more market penetration if awareness is highly created

Phyto-Constituents and Anti-Oxidant Activity of the Pulp of Snake Tomato (Trichosanthes Cucumerina L.)

The phyto-constituents and antioxidant activity of the fruit pulp of Trichosanthes cucumerina L. have not been reported in literature and were therefore studied. Two identified morphotypes of this plant (Morphotype I [V1] having long fruit with deep green background and white stripes; and Morphotype II [V2] having light green coloured long fruit) were used for the studies. The dry matter contents of the pulp of the V1 and V2 were 10.9 and 9.6 g/100g fresh weight (FW), while the ascorbic acid contents were 25.7 and 24.8 mg/100g fresh weight (FW), and lycopene contents were18.0 and 16.1 mg/100g FW, respectively. The total phenolics, total flavonoids and total ferric reducing antioxidant power (FRAP) of V2 were significantly higher (P< 0.05) than that of V1 by 46.8%, 78.0% and 26.2%, respectively. Bulk of the carotenoids is made up of lutein in the concentration of 15.6 and 18.4 mg/100g FW, for V1 and V2, respectively. The α-carotene contents were 10.3 and 10.7 mg/100g FW while the β-carotene contents were 2.4 and 2.8 mg/100g FW for V1 andV2, respectively. It is concluded from the results of this study that the two morphotypes of T. cucumerina possess valuable nutraceutical properties that can qualify them as viable substitute to the Solanaceous tomato

A Review of Postharvest Losses in Fruits and Vegetables in Nigeria: The Need for an Extension Strategy

The paper reviewed cases of postharvest losses of fruits and vegetables in Nigeria and identified an extension strategy to stem the losses. The paper highlighted some harvesting and handling methods that can be presented through the extension services to the farmers to stem postharvest losses. To reach the Nigerian farmers, the paper suggested the use of target system approach will? integrated mass inedia approach, group contact method, all in combination to educate farmers on how to reduce postharvest losses. It was also obsserved that cooperative and collaborative efforts of governments, non- governmental organizations, corporations, individuals and groups are highly necessary in solving the problem of postharvest losses in Nigeria

A Review of Postharvest Losses in Fruits and Vegetables in Nigeria: The Need for an Extension Strategy

The paper reviewed cases of postharvest losses of fruits and vegetables in Nigeria and identified an extension strategy to stem the losses. The paper highlighted some harvesting and handling methods that can be presented through the extension services to the farmers to stem postharvest losses. To reach the Nigerian farmers, the paper suggested the use of target system approach will? integrated mass inedia approach, group contact method, all in combination to educate farmers on how to reduce postharvest losses. It was also obsserved that cooperative and collaborative efforts of governments, non- governmental organizations, corporations, individuals and groups are highly necessary in solving the problem of postharvest losses in Nigeria

Application of biotechnological for the improvement of Nigerian indigenous leaf vegetables

Nigeria is endowed with many indigenous leaf vegetables (ILVs) species, which spread across the estimated cultivable land area of 71.2 million hectares. These ILVs provide food, income, employment and herbal medicine to the population. Uncollected and uncharacterized germplasm, pests, diseases, anti-nutritional factors, recalcitrant seed, seed dormancy and perishable produce militate against the realization of potentials of the ILVs. This paper discusses biotechnological applications such as meristem culture, in vitro selection, zygotic embryo culture, somatic embryo genesis, protoplast culture, anther culture and genetic engineering that can solve improvement and production problems associated with some selected ILVs. Among the problems envisaged in the application of these biotechnological techniques are lacks of resources, selections of crop for research, attitude of government and weather conditions.African Journal of Biotechnology Vol. 4 (2), pp. 138-142, 200

Extraction Optimization and Antioxidant Properties of African Eggplant (Solanum macrocarpon) Leaf Polyphenols

Optimization of the yield, total phenolic content (TPC), and total antioxidant activities (TAA) of polyphenol concentrates extracted from Solanum macrocarpon leaves was studied using response surface methodology. The process variables investigated included extraction temperature (30, 50, and 70°C), extraction time (2, 4, and 6 h), and dried leaf powder : water ratio (1 : 10, 1 : 20, and 1 : 30 w/v). Box–Behnken design resulted in 15 experimental runs. The results showed the following optimum extraction conditions: temperature, 49.05°C; extraction time, 243 min; leaf powder : water ratio, 1 : 22 w/v. The optimized extraction conditions gave polyphenol concentrate yield, TPC, and TAA values of 24.94%, 421.09 mg GAE/g, and 23.81 mg AAE/g, respectively. Results of the in vitro antioxidant activities of the polyphenol concentrate showed 2, 2-diphenyl-2-picrylhydrazyl hydrate, metal chelating ability, and ferric reducing ability values of 76.78%, 80.22%, and 56.46 mg AAE/g, respectively. The study concludes that the experimental values compared closely with the predicted values, which indicates suitability of the model employed for polyphenol extraction optimization from dried S. macrocarpon leaves

In Vitro Characterization of Fluted Pumpkin Leaf Protein Hydrolysates and Ultrafiltration of Peptide Fractions: Antioxidant and Enzyme-Inhibitory Properties

Hydrolysates were produced using Alcalase (AH), chymotrypsin (CH), pepsin (PH), and trypsin (TH), and also fluted pumpkin leaf protein isolate (FLI) as a substrate. AH had the lowest degree of hydrolysis (16.37%) but exhibited overall superior antioxidant and enzyme inhibitory properties. Therefore, it was fractionated by membrane ultrafiltration to give 10 kDa peptide fractions. Gel permeation chromatography showed that the molecular weight of the FLI was 19.77 kDa and that of the hydrolysates was below 7.5 kDa. The hydrolysate peptides had a high content of hydrophobic amino acids but low levels of sulfur-containing amino acids, when compared to protein of FLI. Peptide sequence analysis showed that the hydrolysates consisted of dipeptides, tripeptides, and tetrapeptides with molecular weights below 500 Da. The hydrolysates were also stronger inhibitors of linoleic acid oxidation, α-amylase, α-glucosidase, and angiotensin converting enzyme (ACE) than FLI. Among the fractions, the <1 and 1-3 kDa were the most effective free radical scavengers and metal chelators in addition to their strong inhibitory activities against α-amylase, α-glucosidase, and ACE. We conclude that the AH and low molecular weight peptide fraction (<3 kDa) could find applications in formulating foods with various bioactive properties