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Hydroxy marilone C is a bioactive metabolite produced from the culture broth of Streptomyces badius isolated from Egyptian soil. Hydroxy marilone C was purified and fractionated by a silica gel column with a gradient mobile phase dichloromethane (DCM):methanol then Sephadex LH-20 column using methanol as a mobile phase. It was subjected to many procedures such as infrared (IR), nuclear magnetic resonance (NMR), Mass spectroscopy (MS) and UV spectroscopy for elucidation of its structure. It was evaluated for antioxidant, cytotoxicity against human alveolar basal epithelial cell line (A-549) and human breast adenocarcinoma cell line (MCF-7) and antiviral activities; showed that the maximum antioxidant activity was 78.8% at 3 mg/ml after 90 min. and the IC50 value against DPPH radical found about 1.5 mg/ml after 60 min. Using MTT assay the effect of the pure compound on the proliferation of A-549 cells and MCF-7 cells was 443 μg/ml and 147.9 μg/ml, respectively, while for detection of antiviral activity using Madin–Darby canine kidney (MDCK) cells the maximum cytotoxicity was at 27.9% and IC50 was 128.1 μg/ml. The maximum concentration required for protecting 50% of the virus-infected cells against H1N1 viral cytopathogenicity (EC50) was 33.25% for 80 μg/ml. These results indicated that the hydroxy marilone C has potential antitumor and antiviral activities.

The release of different hazardous substances into the water bodies during the industrial and textile processing stages is a serious problem in recent decades. This study focuses on the potentiality of Fe3O4-NPs-based polymer in sustainable bioremediation of toxic substances from contaminated water. The biosynthesis of Fe3O4-NPs by A. tamarii was performed for the first time. The effect of different independent variables on the Fe3O4-NPs production were optimized using Plackett–Burman design and central composite design (CCD) of Response Surface Methodology. The optimum Fe3O4-NPs production was determined using incubation period (24 h), temperature (30 °C), pH (12), stirring speed (100 rpm) and stirring time (1 h). The incorporation of Fe3O4-NPs into chitosan beads was successfully performed using sol–gel method. The modified nanocomposite exhibited remarkable removal capability with improved stability and regeneration, compared to control beads. The optimal decolorization was 94.7% at 1.5 g/l after 90 min of treatment process. The reusability of biosorbent beads displayed 75.35% decolorization after the 7th cycle. The results showed a highly significant reduction of physico-chemical parameters (pH, TDS, TSS, COD, EC, and PO4) of contaminated wastewater. The sorption trials marked Fe3O4-NPs-based biopolymer as efficient and sustainable biosorbent for the elimination of hazardous toxic pollutants of wastewater in a high-speed rate.

73 species which belong to 24 genera were collected in 200 and 35 exposures made during the period May 1976-October 1977 at each of two levels (2 m and 20 m). The air-borne fungi showed seasonal periodicities and the highest incidence was recovered in spring and autumn and the least in the summer. Aspergillus was the dominating genus. 17 species were collected at the two levels of which A. niger and A. flavus were the most common. Other common genera were Cladosporium which was represented by C. herbarum, C. cladosporioides, C. sphaerospermum, and C. macrocarpum. 7 species of Curvularia were identified of which C. pallescens was the most frequent at the low and C. spicifera at the high level. Drechslera was represented by 6 species of which D. halodes was the most common at the two levels. Only one Alternaria species, A. alternata was isolated at both levels. 10 Penicillium were recovered, P. notatum was the most frequently one isolated at the two levels. Many fungal spore showers of Cladosporium, Aspergillus, Curvularia, and Alternaria were recorded during the experimental period.

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Polyhydroxybutyrate (PHB) is a biosynthetic and biodegradable plastic which attracts attention du to its properties. Out of nine Actinomycetes isolates obtained from different soil samples, the PHB accumulating isolate was identified by molecular studies and was identified as Streptomyces incanus BK128. Different agricultural waste (wheat bran, rice bran, rice straw and molasses) were employed for polyhydroxybutyrate (PHB) production as the main carbon source. Some supplements such as (0.4 g) ammonium sulphate were used to optimize the PHB production medium. The maximum PHB production was achieved with wheat bran (1.9g/l). Different parameters including; the initial pH of the medium, ammonium chloride concentration and inoculum size; were carried out under shaking flask conditions (150 rpm) at 30ºC for 5 days of incubation to enhance the PHB production. The maximum PHB production (2.82gl-1) was achieved at pH 6.5, (2%) NH 4 CL and 5 ml inoculum size, respectively. The effect of gamma irradiation on the activity of Streptomyces incanus BK 128 towards PHB production showed that, at dose level 1.5 kGy, the maximum PHB production obtained was 3.39 gl-1 .

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