Various strains of Aspergillus niger were screened for extracellular glucose oxidase (GOD) activity. The most effective producer, strain FS-3 (15.9 U mL(-1)), was mutagenized using UV-irradiation or ethyl methane sulfonate. Of the 400 mutants obtained, 32 were found to be resistant to 2-deoxy D: -glucose, and 17 of these exhibited higher GOD activities (from 114.5 to 332.1%) than the original FS-3 strain. Following determination of antifungal resistance of the highest producing mutants, four mutants were selected and used in protoplast fusions in three different intraspecific crosses. All fusants showed higher activities (from 285.5 to 394.2%) than the original strain. Moreover, of the 30 fusants isolated, 19 showed higher GOD activity than their corresponding higher-producing parent strain.

Microbiological and sensory characteristics of treated whole and peeled shrimp from the east coast of Saudi Arabia were evaluated. Shrimp samples were treated with organic acid salts with or without Bifidobacterium breve culture and stored in ice. Peeling alone extended the microbiological shelf life by 4 days. Treatment of whole shrimp with sodium acetate alone or potassium sorbate with bifidobacteria prolonged the microbiological shelf life by 3 days and increased the microbial generation time from 12.8 h (control) to 30.1 h or 31.4 h, respectively. The microbiological and sensory shelf life of peeled shrimp treated with sodium acetate was more than 17 days. Sodium acetate extended the microbial lag phase and lengthened the generation time (38.7 h compared to 15.8 h for the control). Micrococci and coryneforms were the predominant microorganisms in whole shrimp during storage. Treatment with sodium acetate maintained better sensory characteristics for peeled shrimp than potassium sorbate combined with bifidobacteria.

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The experimental trial was consummated during two successive seasons (2011/ 2012 and 2012/ 2013) at the nursery of Hort. Res. Inst., Giza, Egypt. It was intended to find out the solve of one of the most important problems faced the production of Gladiolus in Egypt, i.e. the deterioration of corms production year after year. So, the independent as well as the combined effects of different growing media (sand, sand/compost 1:1 v/v and sand/sewage sludge 3:1 v/v), fertilization treatments (NPK at 1:2:1, kristalon and EM 5%) and their interaction were investigated on the production of Gladiolus corms from cormlets locally. The results indicated that growing cormlets in sand/compost (1:1 v/v) medium proved its mastery in raising corms yield, corm fresh and dry weights, corm circumference and root length of corm as well as cormlets yield and quality in both seasons. Meanwhile, using sand medium in plantation achieved the second rank in improving the same parameters in the same seasons. Results indicated also the prevalence of all corms and cormlets parameters due to applying the mixture of N, P and K, whereas kristalon and EM 5% showed less effect in this regard. Chemical constituents of the new formed corms were also affected by the previous treatments, where growing cormlets in sand/compost medium showed its superiority in raising N, P and K as well as total carbohydrates content in the new corms. Also, NPK fertilization revealed an increment on the same parameters in the same organ. From the aforementioned results and interactions, it could be recommended to grow Gladiolus (cv. Novalux) cormlets in sand/compost medium along with treating the plants with NPK mixture at a ratio of 1: 2: 1 at the rate of 2 g/pot, 8 times at 15 day intervals to obtain high yield and quality of the new formed corms.