RESUMO
Microalgae have the highest capability to fix the atmospheric carbon and wastewater-derived nutrients to produce high-value bioproducts including lipids and carotenoids. However, their lower titers and single-product-oriented biomass processing have made the overall process expensive. Hence, increased metabolite titer and processing of the biomass for more than one product are required to ensure the commercial robustness of the algal biorefinery. In this study, a newly isolated algal strain was identified as Bracteacoccus pseudominor BERC09 through phylogenetic analysis based on the 18S rRNA gene sequence. Basic characterization of the strain revealed its promising potential to produce carotenoids and lipids. The lipids and carotenoid biosynthesis pathways of BERC09 were further triggered by manipulating the abiotic factors including nitrogen sources (NaNO3, KNO3, NH4Cl, Urea), nitrogen concentrations (0.06-0.36 gL-1), light intensity (150 µmolm-2s-1 to 300 µmolm-2s-1), and light quality (white and blue). Resultantly, 300 µmolm-2s-1 of blue light yielded 0.768 gL-1 of biomass, 8.4 mgg-1 of carotenoids, and 390 mgg-1 of lipids, and supplementation of 0.36 gL-1 of KNO3 further improved metabolism and yielded 0.814 gL-1 of biomass, 11.86 mgg-1 of carotenoids, and 424 mgg-1 of lipids. Overall, the optimal combination of light and nitrogen concurrently improved biomass, carotenoids, and lipids by 3.5-fold, 6-fold, and 4-fold than control, respectively. Besides, the excellent glycoproteins-based self-flocculation ability of the strain rendered an easier harvesting via gravity sedimentation. Hence, this biomass can be processed in a cascading fashion to use this strain as a candidate for a multiproduct biorefinery to achieve commercial robustness and environmental sustainability.
Assuntos
Clorofíceas , Microalgas , Biomassa , Carotenoides/metabolismo , Clorofíceas/metabolismo , Lipídeos , Microalgas/metabolismo , Nitrogênio/metabolismo , FilogeniaRESUMO
The palm oil mill effluent (POME) from palm milling oil activities is discharged into various water bodies which poses several environmental problems including turbidity, increases COD and BOD, adds oil and grease, increases total nitrogen, and other pollutants. Therefore, it requires effective treatment to remove the pollutants before disposal. The objective was to critically discuss the performance of POME pretreatments along with their limitations. To offer a coverage on the present less efficient technologies, the opportunities and challenges of advanced pretreatments that combine magnetic materials and natural composites as adsorbents are comprehensively reviewed here. Moreover, potential of various magnetic materials for POME pretreatment has been described. Several existing pretreatment methods such as physical pretreatments, chemical pretreatments, coagulation-flocculation, and adsorption can remove pollutant content from POME with certain limitations and the use of magnetic composite adsorbents can enhance the treatment efficiency.
Assuntos
Resíduos Industriais , Eliminação de Resíduos Líquidos , Resíduos Industriais/análise , Óleo de Palmeira , Óleos de Plantas , TecnologiaRESUMO
Water shortage is one of the leading global problems along with the depletion of energy resources and environmental deterioration. Recent industrialization, global mobility, and increasing population have adversely affected the freshwater resources. The wastewater sources are categorized as domestic, agricultural and industrial effluents and their disposal into water bodies poses a harmful impact on human and animal health due to the presence of higher amounts of nitrogen, phosphorus, sulfur, heavy metals and other organic/inorganic pollutants. Several conventional treatment methods have been employed, but none of those can be termed as a universal method due to their high cost, less efficiency, and non-environment friendly nature. Alternatively, wastewater treatment using microalgae (phycoremediation) offers several advantages over chemical-based treatment methods. Microalgae cultivation using wastewater offers the highest atmospheric carbon fixation rate (1.83 kg CO2/kg of biomass) and fastest biomass productivity (40-50% higher than terrestrial crops) among all terrestrial bio-remediators with concomitant pollutant removal (80-100%). Moreover, the algal biomass may contain high-value metabolites including omega-3-fatty acids, pigments, amino acids, and high sugar content. Hence, after extraction of high-value compounds, residual biomass can be either directly converted to energy through thermochemical transformation or can be used to produce biofuels through biological fermentation or transesterification. This review highlights the recent advances in microalgal biotechnology to establish a biorefinery approach to treat wastewater. The articulation of wastewater treatment facilities with microalgal biorefinery, the use of microalgal consortia, the possible merits, and demerits of phycoremediation are also discussed. The impact of wastewater-derived nutrient stress and its exploitation to modify the algal metabolite content in view of future concerns of cost-benefit ratios of algal biorefineries is also highlighted.
Assuntos
Microalgas/fisiologia , Eliminação de Resíduos Líquidos/métodos , Carbono , Sequestro de Carbono , Poluentes Ambientais , Nitrogênio , Fósforo , Águas ResiduáriasRESUMO
BACKGROUND: This study was conducted to evaluate the effect of Vitamin C on Monosodium Glutamate induced histopathological changes in oviduct of adult female Sprague Dawley rats. The duration of study was 6 months. It was an analytical experimental randomized control trial. METHODS: In this experimental study, 45 female adult Sprague Dawley rats of 10-14 weeks were used and divided into 3 groups. Each group contains 15 rats. Control group (C) received standard laboratory diet. Experimental group A, was given Monosodium Glutamate (0.08 mg/kg body weight/ day) whereas experimental group B, was served on both MSG and Vitamin C (250 mg/kg body weight/day). All groups received diet for a period of 4 weeks. After 4 weeks all rats were sacrificed and oviducts were obtained. For the study of tissue under light microscopy, tissue processing was done by using Haematoxylin and Eosin stain and 5micrometer thick sections were taken from the ampullary part of oviduct. RESULTS: After administration of MSG, group A showed vacuolization of epithelial cells, infiltration of RBCs in lumen with substantial decrease in the diameter of oviduct in group A. Protective effects were seen in vitamin C supplemented group B, with decrease in epithelial vacuolization and RBCs infiltrate along with increase in diameter of oviduct. CONCLUSIONS: Vitamin C has protective effect on Monosodium Glutamate induced histological changes in oviduct of rats.