细化搜索
结果 11-16 的 16
Food Technology Research Institute, Agricultural Research Center, Giza, Egypt
2008
Ayman E. M | Nadia M. Abd El-Motaleb | Nadia H. Assem
Day by day increase the importance of using the natural food additives. Hence in this study, the phenolic extracted from basil leaves, spearmint leaves and fennel seeds, as natural antioxidants, were added at concentrations 200, 400 and 600 ppm from fat weight using in biscuit production. Biscuit was stored at room temperature for 8 months. Induction period was measured by Rancimat apparatus. Total phenolic and phenolic acids were determined. Peroxide value, acid value, thiobarbituric acid and refractive index were measured during storage. Antimicrobial activity of phenolic extraction were examined after 8 months. Sensory evaluation was measured directly after baking. The results showed that total phenolic content in basil leaves, spearmint leaves and fen-nel seeds were 3.97, 1.91 and 1.53 mg/g as caffeic acid equivalents respectively. Five phenolic acids were found in both basil leaves and spearmint leaves, while four phenolic acids were found in fennel seeds as determined by using HPLC. Rancimat results showed that induction period for phenolic herbs could be ranked as follow: basil leaves > spearmint leaves > fennel seeds. The re-sults elucidated that the best concentration from natural additives as antioxidants activity were 400 and 600 ppm compared with BHT. The results revealed that with increasing the concentration of natural antioxidants increased, the more peroxide value, acid value, thiobarbituric acid and refractive index were decreased. Total bacterial count and (yeast & mold) count were decreased with increas-ing the concentration phenolic additives. Sensory evaluation indicated that addition of different anti-oxidants showed no significant differences be-tween control and biscuit samples
显示更多 [+] 显示较少 [-]OPTIMIZATION OF A CULTURE MEDIUM FOR BIOMASS AND δ-ENDOTOXIN PRODUCTION BY A RECOMBINANT ESCHERICHIA COLI STRAIN
2008
Rawia F. Gamal | Al-Fateh R. | Abeer Mohammed | M. El-Sawy
A recombinant strain of Escherichia coli harboring a plasmid containing the Bacillus thuringiensis δ-endotoxin synthesis gene, was tested for its efficacy to synthesize δ-endotoxin, in a complex medium containing sucrose and yeast extract. Also, the recombinant E. coli strain was tested for its efficacy against the 2nd instars of Spodoptera littoralis. The recombinant strain of E. coli showed a good activity against the 2nd instars of S. littoralis, the mortality was 70 % after 7 days at room temperature. A high cell biomass (8.8gL-1) and δ-endotoxin concentration (6.8 mg L-1), were obtained by the shake flask culture (100 ml medium/250 ml flask, at 200 rpm), of the recombinant E. coli in modified MR medium containing sucrose (20g/L), as carbon source and yeast extract as nitrogen source, in the presence of CaCO3, K2HPO4, MgSO4, FeSO4 and ZnSO4 as mineral salts. The best pH values for cell biomass production and endotoxin production were 7.0 and 7.5, respectively. The corresponding figures for the best temperature were 37oC and 30oC, respectively. The use of some byproducts such as black-strap molasses, corn-steep liquor and cheese whey, as an alternative for carbon and nitrogen sources of medium, were found to enhance the cell growth but showed no effect on endotoxin production.
显示更多 [+] 显示较少 [-]USE OF WATER HYACINTH (Eichornia crassipes) IN AMELIORATION OF A SANDY SOIL
2008
Mubarak A R | Fattoma A M Rezik | S A Afiah
Soil fertility management is a key issue for sustaining agricultural production in dry lands. Organic resources are important for nutrient avail-ability and maintenance of soil organic matter. Sustaining fertility of arid soils necessitates in-creasing inputs of organic residues. Two experi-ments with water hyacinth were carried out to monitor (in the first; field study with litter bags) decomposition and changes in N, P, K, Ca and Mg as influenced by method of application where, in the second (greenhouse study) short-term effect on some properties of a sandy soil and early estab-lishment of fodder sorghum (Sorghum bicolor). Results of the first experiment showed that resi-dues incorporated in the top 0-30cm soil depth had significantly (P≤0.01) increased loss of dry matter weight compared to surface application. Decom-position rate constants of surface and sub-surface application were 0.029% week-1 and 0.041% week-1, respectively. Potassium was the fastest nutrient released with 50% loss attained after the 2nd and 6th week from incorporation and surface application, respectively. Nitrogen, P, Ca, and Mg releases from water hyacinth incorporated in the sub-soil were significantly (P≤ range from 0.0001 to 0.008) high compared to surface application. Nutrients loss was in the order of K =Mg > P > N > Ca. However, results of the second experi-ment showed that incorporation of water hyacinth residues significantly (P ≤ 0.001) decreased pH (by about 27%) and hydraulic conductivity (by 40-46%). Also, cation exchange capacity and organic C were significantly increased by about 23 and 100%, respectively. The study concluded that ap-plication of water hyacinth could be one of the good alternatives for improving quality of arid soils.
显示更多 [+] 显示较少 [-]CHEMICAL AND TECHNOLOGICAL EVALUATION OF SOME SWEET POTATO VARIETIES
2008
El-Bastawesy Amal | Lobna A. Hareedy | Mervat M. EL-Far
This investigation was carried out to evaluate the chemical characteristics of new eight sweet potato varieties namely, CEMSA 74-228, SANTO AMARA, NC 1525 and KEMB 37 (creamy flesh) and JAPON TRESMESINO, LO 323, TAINUNG 64 and BEAUREGARD (yellow flesh ), and study their suitability for processing. The obtained re-sults reveal that SANTO AMARA and KEMB37 varieties were the best ones having the highest content of chemical constituents compared with those of the other studied creamy flesh sweet pota-to varieties. Moreover, 140 days from planting was the best harvesting time that achieved the highest chemical characteristics. All selected creamy sweet potato varieties had adequate miner-als contents especially, KEMB 37 followed by NC 1525 and CEMSA 74-228 then SANTO AMARA varieties that could be considered good sources of minerals for human nutrition. Yellow flesh sweet potatoes have been recognized as valuable sources of carbohydrates, protein, dietary fibers and could be considered as good sources of both vitamin C and total carotenoids. Moreover, TAINUNG 64 and LO 323 were found to be good sources of β-carotene (pro- vitamin A). The more suitable har-vesting time for yellow sweet potato varieties, which recorded the highest levels of essential ele-ments, was 140 days from planting. On the other hand, TAINUNG 64 variety could be considered the best one compared to the other examined vari-ties. The most suitable varieties that having good quality attributes for processing were SANTO AMARA and KEMB 37 as creamy flesh and TAINUNG 64 and BEAUREGARD as yellow flesh sweet potato varieties. Moreover, these va-rieties could be successfully used in the produc-tion of new and untraditional sweet potato prod-ucts.
显示更多 [+] 显示较少 [-]CHEMICAL COMPOSITION OF CAMEL'S COLOSTRUM AND MILK IN UNITED ARAB EMIRATES
2008
Rea H. Omer | A.H Eltinay
The chemical composition of 350 samples from camel's colostrum and milk in United Arab Emirates were studied. Results of colostrum showed 6.19 for pH, 1.041g/ml for density, 3.1% for fat, 4.95% for protein, 4.4% for lactose, 12.88% for total solids, 10.55% for non fat total solids, 1.11% for ash, 87% for moisture .For ma-ture milk, data were 6.6 for pH, 0.133% for acidi-ty, 1.028g/ml for density, 3.2% for fat, 2.4% for protein, 4.6% for lactose, 11% for total solids, 7.88% for non-fat total solids, 0.88% for ash, and 88.9% for moisture. The minerals contents in camel colostrum were (mg/100mg) as follows: 103 for calcium, 15.4 for magnesium, 14.0 for sodium, 128 for potassium, 0.25 for iron, 0.17 for copper and 43.4 for inorganic phosphate. Elements in mature camel milk were (mg/100mg) as fol-lows: 74.67 for calcium, 3.4 for magnesium, 42.36 for sodium, 136.64 for potassium, 0.18 for iron, 0.04 for copper, 0.02 for manganese, 0.3 for zinc and 38.4 for phosphorus.
显示更多 [+] 显示较少 [-]PRELIMINARY STUDIES ON THE EFFECT OF FOLIAR APPLICATION OF METHANOL AND PINK PIGMENTED FACULTATIVE METHELOTROPHIC BACTERIA ON COTTON PLANT
2008
A pot experiment was carried out in summer season of 2006 to evaluate the different concentrations effect of foliar application of methanol and pink pigmented facultative methelotrophic bacteria (PPFM) on some growth parameters and yield of cotton plant. Data showed that, the highest growth rate value was obtained with PPFM isolates from wheat with 1% methanol. The growth rate of PPFM isolates decreased with increasing the methanol concentration. Foliar applications with 20% methanol with PPFM 3 or 4 spraying times gave the significantly highest values of cotton growth and yield parameters. Such two potent treatments increased leaf area index (LAI) by 51.4 and 55.8 %; number of fruiting branches / plant by 53.1 and 58.0 %; number of total bolls / plant by 38.1 and 43.0 %; seed cotton weight / boll by 37.1 and 48.2 % and seed cotton yield / plant by 46.1 and 50.8, respectively than the control.
显示更多 [+] 显示较少 [-]