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El-Naggar N.E.-A.,Genetic Engineering and Biotechnology Research Institute | El-Hersh M.S.,Water and Environment Research Institute
Journal of Microbiology | Year: 2011

Saccharification of five cellulosic wastes, i. e. rice husks, wheat bran, corn cobs, wheat straw and rice straw by three cellulytic fungi, i. e. Aspergillus glaums MN1, Aspergillus oryzae MN2 and Penicillium purpurogenum MN3, during solid-state fermentation (SSF) was laboratory studied. Rice husks, wheat bran, and corn cobs were selected as inducers of glucose production in the tested fungi. An incubation interval of 10 days was optimal for glucose production. Maximal activities of the cellulases FP-ase, CMC-ase, and β-glucosidase were detected during SSF of rice husks by P. purpurogenum; however, α-amylase activity (7. 2 U/g) was comparatively reduced. Meanwhile, the productivities of FP-ase, CMC-ase, and β-glucosidase were high during SSF of rice husks by A glaucus; however, they decreased during SSF of corn cobs by P. purpurogenum. Addition of rock phosphate (RP) (75 mg P 2O 5) decreased the pH of SSF media. (NH 4) 2SO 4 was found to be less inducer of cellulytic enzymes, during SSF of rice husks by A. glaucus or A. oryzae; it also induced phytase production and solubilization of RP. The organic acids associated with saccharification of the wastes studied have also been investigated. The highest concentration of levulinic acid was detected (46. 15 mg/g) during SSF of corn cobs by P. purpurogenum. Likewise, oxalic acid concentration was 43. 20 mg/g during SSF of rice husks by P. purpurogenum. © 2011 The Microbiological Society of Korea and Springer-Verlag Berlin Heidelberg.

Deraz S.F.,Genetic Engineering and Biotechnology Research Institute
Journal of Aquatic Food Product Technology | Year: 2015

The main objective of the current work was to evaluate the proximate chemical composition and nutritional quality of amino acids of protein hydrolysates from viscera of Tilapia nilotica fish. The results of amino acid composition showed that all hydrolysates contained sufficient and/or excessive amounts of both essential and nonessential amino acids, with appreciable values of essential amino acid/nonessential amino acid ratio (0.77 to 1.59) and essential amino acid/total amino acid ratio (43.35 to 61.35). All protein hydrolysates had a high content of the flavor enhancer amino acids. The lowest values of essential amino acids were found for phenylalanine and methionine with chemical scores ranging from 0.04 to 0.77 and 0.09 to 1.06, respectively, except for 18 h hydrolysates. The protein efficiency ratio had values greatly exceeding 2.0, which is considered a high quality. On the other hand, the levels of sugar and ash contents ranged from 2.69 to 3.32 g L-1 and 0.48 to 2.1%, respectively, with 9.2 to 14% dry matter. Mineral composition showed that sufficient amounts of calcium, sodium, potassium, magnesium, and iron were present. The results suggest that the studied hydrolysates are appropriate for use in balanced human or animal diets. Copyright © 2015 Taylor & Francis Group, LLC.

Amara A.A.,Genetic Engineering and Biotechnology Research Institute
Saudi Pharmaceutical Journal | Year: 2015

Research which concerns the usefulness of Probiotics show increasing interest based on the rise of their publications, products and the awareness of the public of their benefits. There is increasing interest concerning Probiotics from the public, researchers, governmental organizations (such as the WHO/FAO) and medicinal and food companies. Probiotics means "let good microbes work for you in different fields get their benefits and take a rest". Such work will include, food digestion, production of useful products to destroy the bad microbes, complement the functions of the missed digestive enzymes (due to missed or defective genes), and to maintain the digestive system's pH, and so on. Probiotics will augment the efficiency of our biological fermentors, the digestive system. Many authors have described the history and the progress of Probiotics and their different applications. In this review, we will focus mainly on three points, health improvement, infection control and disease management, which could be eliminated by the use of different types of direct uses of Probiotics or by the use of foods containing Probiotics. © 2013.

El-Naggar N.E.-A.,Genetic Engineering and Biotechnology Research Institute | Abdelwahed N.A.M.,National Research Center of Egypt
African Journal of Biotechnology | Year: 2012

One hundred and forty one actinomycetes strains were isolated from Egyptian and Saudi Arabia soils and decayed rice straw samples. The isolated actinomycetes strains were screened for their cellulolytic activities on carboxymethyl cellulose (CMC) -containing agar plates. Streptomyces sp. NEAE-D showed the highest carboxymethyl cellulase (CMCase) activity. The optimum conditions for CMCase production were the use of pretreated rice straw as the best carbon source that supported better CMCase production than carboxymethyl cellulose after 5 days incubation at pH 6.5 and at 35°C in the presence of yeast extract as nitrogen source. Crude CMCase activity was characterized. The highest activity was recorded after 50 min incubation, at 50°C, pH 6.0 and 2% substrate concentration, the CMCase was shown to be alkali-tolerant enzyme whose activity was stable over a broad pH range (7 to 10). The enzyme retained 97.31 and 70.99% of its activity at 50 and 60°C respectively after 60 min. High performance liquid chromatography (HPLC) analysis of the hydrolysate of saccharified pretreated rice straw identified the formation of glucose, cellobiose, mannose and xylose as byproducts. © 2012 Academic Journals.

Elkady M.F.,Advanced Technology and New Materials and Research Institute ATNMRI | Farag S.,Genetic Engineering and Biotechnology Research Institute | Zaki S.,Genetic Engineering and Biotechnology Research Institute | Abu-Elreesh G.,Genetic Engineering and Biotechnology Research Institute | Abd-El-Haleem D.,Genetic Engineering and Biotechnology Research Institute
Bioresource Technology | Year: 2011

Bacillus mojavensis strain 32A that exhibited 96.11% flocculation efficiency for clay suspensions was selected from other 15 comparative strains. Under growth condition, strain 32A was able to produce 5.2g/L of purified biopolymer. Its constituent was mainly polysaccharide and protein with proportional of 98.4-1.6% respectively. FTIR spectrum was confirming its chemical analysis. This biopolymer attain very fast sedimentation rate. The cost-effective biopolymer and CaCl 2 dosages were 3mg/L and 5ml/L respectively that posed 89.7% flocculation efficiency. These dosages were suitable only for clay concentrations -5g/L. The maximum flocculation efficiency of the biopolymer recorded at pH 1.0 of clay suspension. The too high (>75°C) or too low (<25°C) clay suspension temperature was unfavorable for the biopolymer flocculation performance. The biopolymer solution utilized high thermal stability over the temperature range of 5-60°C. Furthermore, its pH stability recorded at pH range of 5-9. © 2011 Elsevier Ltd.

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