Synthetic dyes are widely used by different industries with over 7 ×10 5 metric tons produced globally each year. Dyes pose adverse effects including chemical oxygen demand, visual pollution, cytotoxicity, genotoxicity, mutagenicity and carcinogenicity on various types of living organisms. The versatile white rot fungi (basidiomycetes fungi) have developed specialized ligninolytic enzymes for reductive cleavage of dyes and xenobiotics. The present study optimized the decolorization of Remazol brilliant blue royal (RBBR) dye by enzymatic extracts of Coriolus versicolor and Pleurotus ostreatus. Experiments were carried out by varying one parameter i.e. pH (2.5-6.5), temperature (30 o C-60 o C), enzyme activity (3.3U-20U), dye concentration (10mg/L-125mg/L) and time (0-480mins), while others constant to study its effects on decolorization of RBBR. From the results obtained, the optimum conditions for decolorization of RBBR by extracts of C. versicolor and P. ostreatus were pH 4.0, temperature of 30 0 C, enzyme activity 20U, dye concentrations of 100mg/L and 50mg/L for C. versicolor and P. ostreatus respectively at the end of 480 minutes. At the optimized conditions, decolorizations for C. versicolor and P. ostreatus were 80.42% and 70.42% respectively. Highest laccase activity (19.50U) was recorded in C. versicolor compared to P. ostreatus (1.41U).

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The demand for carotenoids in the global market is rising due to the high rate of degenerative diseases which have their origin from deleterious free radicals. Carotenoids are antioxidant molecules identified as the potential inhibitors of   free radicles. Particularly, Microalgae carotenoids have drawn great attention, ‘due to their high photosynthetic efficiency, lack of land requirement, and ease of scale-up’. Presently, an attempt was made to optimize the primary growth of three microalgae (i.e., Chlorella vulgaris, Microcystis aeruginosa and Scenedesmus obliquus) prior to second fermentation for the production of carotenoids. Response surface methodology (RSM) was used to optimize experimental runs in an orbital shaker (Winpact SI-200, USA) in a controlled setting of pH and temperature. Growth of microalgae was measured as optical density (OD) as well as the total carotenoids (before stress) at the stationary growth stage. Optimum growth of Microalgae was achieved at a range of 250C -300C and pH 8-9 in all the Microalgae. High carotenoids (before stress) was 4.411mg/ml in Scenedesmus obliquus among others; however, this cannot be translated as the highest as carotenoids are optimized during stress.

The success of any microalgal research involves effective methods for sampling environments, isolation, purification and the maintenance of algal strains. The isolation of soil microalgae poses a great challenge since the soil is a home for thousands of different species, including algal species, bacteria, viruses and fungi. As such cultures are susceptible to contamination, which may interfere with algal structure, biomass yield and the erroneous identification of species for molecular genetic analysis. The most common methods for isolation and purification of microalgae are the single cell isolation, serial dilution and a streak plate. This procedure is tedious, time consuming, demands precision and expertise and may not yield results. Thus in the present study, an attempt was made to modify these methods for the isolation of soil microalgae. With the modification, three microalgal sp. were isolated, purified and identified (viz Chlorella vulgaris, Microcystis aeruginosa and Scenedesmus obliquus) in a simplified manner.