Effects of Aspergillus niger (K8) on nutritive value of rice straw

The objective of this study was to evaluate the use of solid state fermentation for the improvement of the quality of rice straw as animal feed. Rice straw was fermented using Aspergillus niger (K8) with and without additional nitrogen source (urea). Cellulose, hemicelluloses, organic matter (OM), dry matter (DM), acid detergent fibre (ADF), neutral detergent fibre (NDF) and acid detergent lignin (ADL) contents of rice straw were determined before and after 10 days of fermentation. Fermentation has significant (P < 0.01) effect on NDF, but not ADF and ADL contents. Addition of urea as nitrogen source significantly reduced (P < 0.01) the NDF and hemicellulose contents of fermented rice straw. Cellulose content of the rice straw was not affected (P > 0.05), but crude protein (CP) increased significantly (P < 0.01) after fermentation. In vitro gas production technique was used to evaluate the effect of the biological treatment on activity of rumen microorganisms. Fermentation of rice straw using A. niger significantly reduced total gas production (P < 0.01), DM disappearance (P < 0.01) and acetate, propionate and  total volatile fatty acids (VFA) production (P < 0.05). Results of the present study showed that solid state fermentation of rice straw using A. niger reduced lignocellulose content, but has negative effect on microbial activity in the rumen ecosystem, presumably due to antagonistic activity of A. niger, or other intermediate products from the fermentation, on the rumen microorganisms.Key words: Aspergillus niger, biomass, solid state fermentation, biological treatment, in vitro gas production

Efficiency of rice straw lignocelluloses degradability by Aspergillus terreus ATCC 74135 in solid state fermentation

The ability of Aspergillus terreus for the production of cellulolytic enzymes and reduction of lignocellulose contents of rice straw in solid state fermentation was investigated in this study. Results suggested that, 8 days fermentation was appropriate, with enzymes activities as follows: FPase = 410.76 U/gDM, CMCase = 351.96U/gDM, -glucosidase = 16.37 U/gDM, xylanase = 6166.01 U/gDM and amyloglucosidase = 425.04 U/gDM (with maximum 993.71 U/gDM on day 6). In addition, the solid state fermentation significantly (P < 0.01) reduced the concentrations of NDF, ADF, cellulose and hemicellulose in the rice straw by 19.96, 13.8, 16.32 and 32.87%, respectively. The high degradation of the hemicellulose was reflected by the high activity of xylanase enzyme, which hydrolyses xylan in hemicellulose to xylose. Higher reducing sugar and microbial cell mass productions were also obtained after 8 days fermentation. Present data showed that, A. terreus is capable of producing high quantity of cellulolytic enzymes for the reduction of lignocellulose contents of biomass in a shorter incubation time when compared with the previously reported for biological treatment of agricultural by-products using white rot fungi.Key words: Aspergillus terreus, biomass, biological treatment, enzyme activity, solid state fermentation

The Influence of Different Stresses on Glomalin Levels in an Arbuscular Mycorrhizal Fungus—Salinity Increases Glomalin Content

Glomalin is a glycoprotein produced by arbuscular mycorrhizal (AM) fungi, and the soil fraction containing glomalin is correlated with soil aggregation. Thus, factors potentially influencing glomalin production could be of relevance for this ecosystem process and for understanding AM fungal physiology. Previous work indicated that glomalin production in AM fungi may be a stress response, or related to suboptimal mycelium growth. We show here that environmental stress can enhance glomalin production in the mycelium of the AM fungus Glomus intraradices. We applied NaCl and glycerol in different intensities to the medium in which the fungus was grown in vitro, causing salinity stress and osmotic stress, respectively. As a third stress type, we simulated grazing on the extraradical hyphae of the fungus by mechanically injuring the mycelium by clipping. NaCl caused a strong increase, while the clipping treatment led to a marginally significant increase in glomalin production. Even though salinity stress includes osmotic stress, we found substantially different responses in glomalin production due to the NaCl and the glycerol treatment, as glycerol addition did not cause any response. Thus, our results indicate that glomalin is involved in inducible stress responses in AM fungi for salinity, and possibly grazing stress

Lactobacillus Pentosus Ita23 and L. Acidipiscis Ita44 Enhance Feed Conversion Efficiency and Beneficial Gut Microbiota in Broiler Chickens

Although the use of probiotics especially Lactobacillus and Bifidobacteria species on growth and feed utilization in poultry production has been extensively studied, the results were inconsistent presumably because the mode of action of probiotic is multi-factorial and each probiotic strain may affect the host in a specific manner. This study investigated the probiotic effect of two strains of Lactobacillus(Lactobacillus pentosus ITA23 and Lactobacillus acidophilus ITA44; 109 cells/kg feed) isolated from mulberry (Morus Alba) silage on the growth performance, cecal microbial population, and blood cholesterol of broiler chickens. One hundred twenty male broiler chicks (Cobb500) were randomLy allocated to two groups (control and treatment) of six replicates (cages) with 10 chicks per cage. Chicks in the control group received a standard diet and those in the treatment group received the same diet supplemented with 109 cells of the above Lactobacillus per kg feed. Supplementation of Lactobacillus did not affect body weight gain (averaged 1604 g at 35 days old) but feed conversion ratio improved (p<0.01) by 6.4% due to reduction in feed intake (p<0.01) by birds in the treatment group. Supplementation also increased the population of Lactobacillusspp. and reduced pathogens E. coli in the cecal samples. Although Lactobacillus supplementation tends to reduce serum total cholesterol, low-density lipoprotein (LDL) and triglyceride concentrations, these values were not significantly different from those of the control group. Results of this study showed that L. pentosus ITA23 and L. acidophilus ITA44 are potential probiotics to be used in poultry diets

Changes in nutritional parameters in diploid and triploid African catfish Clarias gariepinus following chlorpyrifos exposure

There is a paucity of information about the influence of ploidy status on physiological parameters in organisms following contaminant stress. Also, little is known about the changes in nutritional values of fishes in response to the exposure to contaminants. Full-sibling juvenile Clarias gariepinus were exposed to 3 levels (mean measured 8.9, 17.5, or 28.0 µg l-1) of chlorpyrifos for 21 d. The levels of 3 fatty acids (FAs) in the muscle were significantly different between unexposed diploid and triploid fish. In the chlorpyrifos-exposed fish, the levels of most amino acids (AAs), some FAs, protein, and moisture content were affected in the muscle of diploids, while the levels of some FAs and ash content were changed in the muscle of triploid fish. This work represents the first study of changes in FAs and proximate composition in triploid animals in response to environmental stressors. Fewer changes of nutritional values in triploid C. gariepinus under chlorpyrifos exposure may indicate higher adaptability of triploids than diploids towards environmental stressors. Significant changes in the muscle protein content and AA and FA compositions in diploid Clarias gariepinus in response to chlorpyrifos exposure suggest their application as sensitive indicators of aquatic environmental pollution

Changes in nutritional values induced by butachlor in juvenile diploid and triploid Clarias gariepinus

© 2017, Islamic Azad University (IAU). There is a paucity of information about the effects of environmental stressors on nutritional values in fish. This study investigated the effects of the organochlorine pesticide, butachlor, on key indicators of nutritional value in both diploid and triploid African catfish (Clarias gariepinus). Amino acids (AA), fatty acids (FA), and the proximate composition (protein, lipid, moisture, and ash content) in the white muscle of full-sibling juvenile fish were measured following a 21-day exposure to graded butachlor concentrations [mean measured: 26.3, 48.4, and 66.1 µg/L]. No significant differences in AAs, FAs, protein, lipid, moisture, or ash content were observed between unexposed diploid and triploid fish. In diploids, exposure to butachlor significantly altered the concentrations of some of the AAs and FAs, and protein content, when compared to the control group. In triploid fish, however, butachlor treatments had no effect on the AA or proximate composition, but significantly changed the concentration of two individual FAs in the muscle. Butachlor treatments showed fewer changes in the nutritional values of triploid fish. This research is the first to study the nutritional values in any polyploid animals following the exposure to a contaminant