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The biosynthesis of nanoparticles by microorganisms especially endophytic species isolated from medicinal plant are the prime concern of researchers. In the present study, a novel, non-toxic, eco-friendly copper nanoparticles was biosynthesized by endophytic actinomycetes isolate Ca-1 and optimization processes have been endeavored. The endophytic actinomycete Streptomyces capillispiralis Ca-1, was isolated from healthy medicinal plant (Convolvulus arvensis) (L.) collected from Bahariya Oasis-Giza Governorate e Egypt. The isolate was identified by morphological, cultural and molecular identification techniques. The biosynthesis of CuNPs is confirmed by gradual change of biomass filtrate color from light blue into greenish brown color and characterized by an observation of a characteristic absorption peak by UV-Vis spectroscopy at 600 nm. Also, a spherical-monodispersed shaped CuNPs with particle size of 3.6 e59 nm were observed by Transmission Electron Microscopy (TEM). In addition, X-ray diffraction (XRD) exhibited pattern peaks corresponding to 110, 111, 200, 220, 311 and 222 planes, respectively that assigned to face centered cubic forms of metallic copper (JCPDS 04e0836). While FTIR results confirmed the occurrence of bioactive functional groups that are responsible for formation of CuNPs. Moreover, the biosynthesized CuNPs showed various biomedical applications against infectious microorganisms, biocontrol of phytopathogenic fungi and health nasty insects that represent the hopeful uses of copper nanoparticles to be applied as a unique approach to manage these healths threatening problems.

Keratinase are proteolytic enzymes which have gained much attention to convert keratinous wastes that cause huge environmental pollution problems. Ten microbial isolates were screened for their keratinase production. The most potent isolate produce 25.2 U/ml under static condition and was primarily identified by partial 16s rRNA gene sequence as Bacillus licheniformis ALW1. Optimization studies for the fermentation conditions increased the keratinase biosynthesis to 72.2 U/ml (2.9-fold). The crude extracellular keratinase was optimally active at pH 8.0 and temperature 65 °C with 0.7% soluble keratin as substrate. The produced B. licheniformis ALW1 keratinase exhibited a good stability over pH range from 7 to 9 and over a temperature range 50–60 °C for almost 90 min. The crude enzyme solution was able to degrade native feather up to 63% in redox free system.

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I N this study, fungal isolate D2-1 was isolated from contaminated soil collected from textile industry companies and showed high potentiality for decolorization of two different azo dyes. This isolate was identified as Aspergillus niger D2-1 using morphological and cultural characteristic as well ITS gene sequencing. Decolorization process under different optimized condition of azo dye concentration, pH, incubation periods, inoculum size and different carbon and nitrogen sources were investigated. The maximum decolorization efficiency against 100 ppm dye concentration of reactive yellow (4GL) and reactive red (4BL) dyes of 98.62 %and 92.42 %, respectively, were recorded for Aspergillus niger D2-1 at pH 9.0, in presence of 2 % glucose and 0.5% yeast extract as carbon and nitrogen sources respectively at room temperature after 7 days on shaking conditions. The decolorization percentage was confirmed by ultraviolet-visible (UV-Vis) spectrum analysis of untreated/treated reactive yellow (4GL) and reactive red (4BL) dyes, which showed complete disappearance of peaks at ~ 425 nm and at ~ 520 nm, indicates the degradation of dyes due to fungal activity. Treatment of textile wastewater effluent by Aspergillus niger D2-1showed high decolorization percentage (59%) for effluent, also physico-chemical characteristics of textile effluent such as chemical oxygen demand (COD), total dissolved solids(TDS) and total suspended solids (TSS) were decreased from 756 mg/L, 1597 mg/Land 821 mg/L to 391 mg/L, 845 mg/L and 362 mg/L respectively. Moreover, Gas chromatography-mass spectroscopy (GC-MS) of textile effluent before and after treatment were recorded and confirmed the potentiality of Aspergillus niger D2-1 in dyes wastewater treatment.

Various challenges facing the industrial production of bio-based lactic acid (LA) such as cost of raw materials and nitrogen sources, as well as contamination risk by mesophilic and neutrophilic producers, should be overcome for the commercial production. This study aimed to investigate the feasibility of corn steep water (CSW) as a raw material for LA production using a newly thermo-alkali-tolerant lactic acid bacterium. The physicochemical characteristics of CSW were investigated. The high carbohydrates, proteins, amino acids, vitamins, essential elements, minerals, and non-protein nitrogenous compounds content confirmed that the CSW is a promising substrate for LA production. Out of 67 bacterial isolates, Enterococcus faecium WH51-1 was selected based on its tolerance to high temperatures and inhibitory compounds (sodium metabisulfate, sodium chloride, sodium acetate, and formic acid). Fermentation factors including sugar concentration, temperature, inoculum size, and neutralizing agents were optimized for LA production. Lactic acid concentration of about 44.6 g/L with a high yield (0.89 ± 0.02 g/g) was obtained using 60 g/L of CSW sugar, inoculum size 10% (v/v), 45 °C, and sodium hydroxide or calcium carbonate as a neutralizing agent. These results demonstrated the potential of strain WH51-1 for LA production using CSW effluent as raw material.

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