Phytochemicals in Leaves and Roots of Selected Kenyan Orange Fleshed Sweet Potato (OFSP) Varieties

This study reports the inherent phytochemical contents in leaves and roots of nine sweet potato varieties from Kenya. Results indicated that vitamin C content varied significantly (P<0.05) among the sweet potato varieties regardless of the plant part, leaves having significantly (P<0.05) higher levels than in the roots. Total flavonoids and phenolic compounds differed significantly (P<0.05) among varieties, higher values were found in leaves than in roots. Flavonoid contents in roots ranged from below detectable limits (Whitesp) to 25.8 mg CE/100 g (SPK031), while in leaves it ranged from 4097 to 7316 mg CE/100 g in SPK4 and Kenspot 5, respectively. Phenolic content was below detectable limits in the roots of whitesp but it was in substantial amounts in orange fleshed varieties. The β-carotene content was significantly (P<0.05) higher in leaves (16.43–34.47 mg/100 g dry weight) than in roots (not detected—11.1 mg/100 g dry weight). Total and phytic phosphorus were directly correlated with phytate contents in leaves and the roots. Tannins and soluble oxalates varied significantly (P<0.05) with variety and plant part being higher in leaves. The current information is important for ration formulations and dietary recommendations utilizing sweet potato leaves and roots. Future studies on effects of processing methods on these phytochemicals are recommended.

Evaluation of Enzyme Additives on the Nutritional Use of Feeds with a High Content of Plant Ingredients for Mugil cephalus

The Mugilidae are a group of fish with a great interest for aquaculture due to their omnivorous profile, rapid growth, and resistance to environmental variations. The selection of feed ingredients for these species is currently focused on an extensive use of plant by-products, with this being limited by their content in anti-nutritive factors (mainly phytate and non-starch polysaccharides; NSPs). Nevertheless, specific enzymes can be used to counteract some of those negative effects. In the present study, the effect of pretreating two high-plant feeds with a mixture of enzymes (glucanases + phytase) on the digestive use of protein and phosphorus by juvenile mullets (Mugil cephalus) was assessed using both in vitro and in vivo assays. The enzymatic treatment significantly modified the potential bioavailability of some nutrients, such as a reduction of sugars, pentoses, and phytic phosphorus. Also, it increased the digestibility of protein in one of the feeds but reduced that of phosphorus in both of them. The potential usefulness of enzyme treatment and the information provided by the two types of assays are discussed.

lpa1-5525: A New lpa1 Mutant Isolated in a Mutagenized Population by a Novel Non-Disrupting Screening Method

Phytic acid, or myo-inositol 1,2,3,4,5,6-hexakisphosphate, is the main storage form of phosphorus in plants. It is localized in seeds, deposited as mixed salts of mineral cations in protein storage vacuoles; during germination, it is hydrolyzed by phytases to make available P together with all the other cations needed for seed germination. When seeds are used as food or feed, phytic acid and the bound cations are poorly bioavailable for human and monogastric livestock due to their lack of phytase activity. Therefore, reducing the amount of phytic acid is one strategy in breeding programs aimed to improve the nutritional properties of major crops. In this work, we present data on the isolation of a new maize (Zea mays L.) low phytic acid 1 (lpa1) mutant allele obtained by transposon tagging mutagenesis with the Ac element. We describe the generation of the mutagenized population and the screening to isolate new lpa1 mutants. In particular, we developed a fast, cheap and non-disrupting screening method based on the different density of lpa1 seed compared to the wild type. This assay allowed the isolation of the lpa1-5525 mutant characterized by a new mutation in the lpa1 locus associated with a lower amount of phytic phosphorus in the seeds in comparison with the wild type.

The effect of dietary phytase and various available phosphorus levels on performance and egg quality in Japanese quail

SUMMARY Birds show poor utilization of phytic phosphorus in their diets because of the lack of endogenous enzymes to digest phosphorus and make it bioavailable. Therefore, the objective of this study was to evaluate phytase supplementation in the diets of laying quails. Eighty quails were used in a completely randomized experimental design with five treatments and four replicates of four birds each. The treatments were as follows: 0.35% Pd; 0.20% Pd; 0.20% Pd + 500FTUs of phytase; 0.09% Pd; 0.09% Pd + 500 FTUs of phytase. The birds were housed in metallic batteries during a trial period of 21 days, for evaluation of egg production, egg weight, feed intake and feed conversion. After being collected, the eggs were sent to the nutrition laboratory of the department of zootechnics of the CEO/Udesc, where analyses of albumin, yolk and shell quality were performed. The results were subjected to analysis of variance, and the differences between the averages were compared using the Tukey test at 5% of significance. No differences (P> 0.05) were observed in terms of performance and egg quality parameters. We conclude that the inclusion of phytase in the diet of laying quails can be accomplished without compromising the performance and quality of the eggs. Additionally, 0.09% of 22 disponible phosphorus can be used to grant adequate performance for 21 days.

Inheritance of inorganic and phytic phosphorus in maize (Zea mays L.) kernel

A set of fifteen elite inbred lines of maize (used as mothers) and three tester inbred lines (used as fathers) were investigated using line x tester statistical model, including both hybrids and inbreds. Four traits were measured: grain yield, 1000 kernel weight, phytic phosphorus (Pphy) and inorganic phosphorus (Pi) in the kernel. Pphy content among hybrids ranged from 2.342 to 4.812 g kg-1 and Pi content from 0.562 to 2.340 g kg-1, while among inbreds (lines and testers) they ranged from 2.503 to 4.180 g kg-1 and from 0.587 to 1.629 g kg-1, respectively. Correlations between the four traits allow breeding for high Pi and low Pphy, as well as for both high Pi and phytate, without compromising grain yield. Correlation for hybrids between Pphy and Pi was 0.185 (p<0.05) and for inbreds 0.142 (non-significant). General combining ability/special combining ability (GCA/SCA) values for all the traits were below 1 (very low) indicated non-additive inheritance. In the investigated set of genotypes, multiple selection indices should be used for simultaneous improvement of grain yield and phosphorus profile of maize grain.

Effect of Processing on Phytic Phosphorus Content in Maize

The main objective of this study was to determine the effect of processing on phytic phosphorus content in maize. An analytical comparison of effect of different methods of processing for reducing phytic phosphorus was carried out on maize. The maize is a staple crop and many rely on it as a primary source of nutrition. Though phytic phosphorus content makes minerals unavailable for absorption yet is used by majority of population. Six cultivars of maize namely VL-16, VL-41, VL-42, D741, D823 and D771 were processed to observe the reduction in phytic phosphorus content. Phytic phosphorus content of the different maize varieties ranged from 143.5 to 167.9 mg/100 g. Variety VL 41 showed highest phytic phosphorus content of 167.9 mg/100 g. Lime treatment was observed to cause significant reduction in phytic acid. Boiling and lime treatment reduced phytic phosphorus by 24.84 and 33.60 % respectively. Variety D771 of maize showed highest reduction of 108.9 mg/100 g after heat treatment and 89.8 mg/100 g after lime treatment. The total reduction in phytic phosphorus was 33.60%.

NUTRITIONAL POTENTIAL OF CASSAVA PEELS ENSILED WITH MORINGA, GLIRICIDIA AND LEUCAENA LEAVES

The experiment was conducted to assess the proximate composition, mineral content, gross energy and antinutrients of cassava peels ensiled with Moringa, Gliricidia and Leucaena leaves. The crude protein for cassava peels ensiled with Moringaoleifera (CMO) was 20.32g100g-1, cassava peels ensiled with Leucaenaleucocepphala(CLL) was 23.17g100g-1 and cassava peels ensiled with Gliricidiasepium (CGS) was 22.23g100g-1. Ether extract values were 4.02g100g-1, 3.56g100g-1 and 3.20g100g-1 for CMO,CLL and CGS respectively. Ash content for cassava peels ensiled with Moringa, Leucaena and Gliricidiawere 4.26g100g-1, 3.80g100g-1 and 4.20g100g-1 respectively. The crude fibre ranged from 12.03g100g-1 in CLL to 12.56g100g-1 in CGS. In cassava peels ensiled with Moringa, Leucaena and Gliricidia leaves Na, K, Ca, Zn were the most abundant minerals in all the treatments.The tannin content varied from 0.20g100g-1 in CMO to 0.45g100g-1 in CGS. The phytic acid ranged from 10.12g100g-1 in CMO to 14.76g100g-1 in CGS. The phytic-phosphorus ranged from 2.85g100g-1 in CMO to 4.16gg100g-1 in CGS. The oxalate contents were 2.85g100g-1, 3.52g100g-1 and 4.16g100g-1 in CMO, CLL and CGS respectively. It is evident that cassava peels ensiled with Moringa, Leucaena and Gliricidia have great potentials for livestock animals and could be utilized as a source of supplementary feed for ruminant animals.

Genetic variability for feeding value of faba bean seeds (Vicia faba): Comparative chemical composition of isogenics involving zero-tannin and zero-vicine genes

In a preliminary experiment, 74 faba bean genotypes including winter genotypes (autumn-sown) and spring genotypes (spring-sown) and isogenic population pairs (tannin-containing v. tannin-free and vicine/convicine-high v. vicine/convicine-low), were analysed for the chemical composition of their seeds. A large variability was found for the main constituents (starch, protein and fibre). Autumn-sown genotypes contained 2·3% less proteins but 2·5% more starch in the seed dry matter (DM) than spring-sown genotypes. The vc− gene, which lowers the vicine and convicine contents, did not significantly modify the main seed components in the isogenic comparisons. The zt1 and zt2 genes, which eliminate condensed tannins in the seed coats, lowered by 2·1% the proportion of the seed coat in the DM. In the isogenic comparisons, the zt2 gene had a stronger effect than zt1 in reducing the total seed fibre and increasing the protein content.In a second experiment, from the original 74 genotypes, 12 contrasted genotypes were selected and multiplied for animal nutrition trials. Their chemical analysis confirmed the variability between the faba bean categories observed in Expt 1, but detailed chemical analyses illustrated the variability in amino acid, fatty acid, amylose and oligosaccharide composition, trypsin inhibitory activity, condensed tannins, lectins and phytic phosphorus contents.