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Background Amylases are amongst the most important hydrolytic enzymes that are used in numerous industrial uses reaching for food to pharmaceuticals. Immobilization of enzymes can proposal several assistances as reusability and retrieval from their products improve strength under both operating and storing environments. Results Marine fungal isolate was recovered from red sea water at Sharm El-Sheikh Province and was tested for amylase activity using different agricultural wastes as substrate. It was found that pomegranate peel was the best substrate for amylase production (339 U/ml). Thus, it was subjected for identifying by 18S rDNA gene. The phylogenetic analysis results indicated that this fungal isolate belonged to Aspergillus species with similarity of 99% and named as Aspergillus terrus SS_RS-NE. Its nucleotide sequences were deposited in NCBI GenBank under accession no. of MN901491. Some parameters affecting amylase activity using pomegranate peel as substrate were studied. The results denoted that, the highest amylase activity of 340.69 U/ml using 1.5% pomegranate peel at 30 °C, pH 6.0 on 5 days incubation time by Aspergillus terreus. The produced crude enzyme was partially purified with 80% ammonium sulfate followed by dialysis. The enzyme activity was 1246 U/ml and 2411 U/ml employing ammonium sulfate precipitation and dialysis respectively. The partially purified amylase was immobilized with 2% sodium alginate and the results showed the highest immobilized enzyme yield was 92.8%. The characterizations of immobilized amylase were studied and the results indicated that, the maximal immobilized amylase activity was 2522.5 U/ml with 2% starch as a substrate at optimum pH value of 6.5, temperature at 60 °C and 10 min reaction time in comparison to maximal free amylase enzyme at pH 5, 50 °C after 40 min. The results also indicated the immobilized amylase was stable at 60 °C for 20 min. Conclusions Aspergillus terrus SS_RS-NE (MN901491) was isolated and genetically identified. It has the ability to produce amylase enzyme using pomegranate peel waste with a yield of 339 U/ml. The crude enzyme was partially purified by ammonium sulfate followed by dialysis. The maximal immobilized amylase activity of 2522.5 U/ml was obtained under optimized some culture conditions and medium nutrient parameters.

Background Xylanase enzyme plays an important role in nature as being a part of protecting the environment from pollution. It has also various industrial applications. Main body of abstract Marine fungal isolate was recovered from red sea water at Sharm El-Sheikh province, Egypt, and tested for xylanase activity, using different agricultural wastes as a substrate. It was found that rice straw was the best substrate for xylanase production (0.37 U/ml). Thus, it was subjected for identification by 18S rDNA gene. The phylogenetic analysis results indicated that this fungal isolate belonging to Aspergillus species with a similarity of 99% and named as A. oryzae SS_RS-SH (MN894021). The regular two-level factorial design was used to optimize the important medium components, which significantly affected the xylanase production. The model in equation suggested optimal conditions of 2% of rice straw, 8 g/l of yeast extract, 4 g/l of (NH4)2SO4, 2 g/l K2HPO4, and 2.5 g/l MgSO4.7H2O for a maximum xylanase yield. The antifungal activity of crude xylanase on mycelial growth of some pathogenic fungi isolated from different hosts was investigated. The results showed that xylanase T1 had a potent antifungal activity than control. Greenhouse experiments indicated that all treatments with xylanase at different concentrations significantly decreased infection occurrence of beans, which have been effectively infected with root rot pathogens, compared to unprocessed control treatments. Short conclusion Xylanase yield increased 2.43-folds than initial screening. The xylanase had a potential antifungal activity both in vitro and under greenhouse conditions. The outcome of this study ensured that this fungal strain could be used as biological control for plant disease.

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Oil paintings consist of several layers, cellulose is the main components of all types supports of oil painting either it was canvas, paper or wood. The deacidification of canvas oil painting was studied. Cellulose is oxidized by air and hydrolyzed by water vapor, The oxidation process creates acid groups that lower the pH of the canvas which cause the loss of canvas oil paintings mechanical properties. Nanoparticles of Ca(OH)2 can be dispersed in different solvents (e.g. short chain alcohols) and applied on canvas, to balance acidity and long-term protection. The characterization of nanoparticles was carried out by transmission electron microscopy (TEM), regular shape of particles can be seen. Scanning electron microscope (SEM) show stable fiber of cellulose. Canvas samples were artificially aged after deacidification using calcium hydroxide nanoparticles dispersed in short chain alcohols. Cellulose pyrolysis temperature and samples' pH were evaluated after and before the artificially aging, the applied deacidification treatments raised samples pH to slightly basic values, these values remained constant upon artificial aging.