Plant Mol Biol
July 2024
Under nitrogen deprivation (-N), cyanobacterium Synechocystis sp. PCC 6803 exhibits growth arrest, reduced protein content, and remarkably increased glycogen accumulation. However, producing glycogen under this condition requires a two-step process with cell transfer from normal to -N medium.
View Article and Find Full Text PDFEnergy is a crucial entity for the development and it has various alternative forms of energy sources. Recently, the synthesis of nanoparticles using benign biocatalyst has attracted increased attention. In this study, silver nanoparticles were synthesized and characterized using Azadirachta indica plant-derived phytochemical as the reducing agent.
View Article and Find Full Text PDFPhotoautotrophic cyanobacteria assimilate the greenhouse gas carbon dioxide as their sole carbon source for producing useful bioproducts. However, harvesting the cells from their liquid media is a major bottleneck in the process. Thus, an easy-to-harvest method, such as auto-flocculation, is desirable.
View Article and Find Full Text PDFThis study investigates nutrient recovery from synthetic municipal wastewater using co-immobilized cultures of Chlorella vulgaris TISTR 8580 (CV) and plant growth-promoting bacteria, Bacillus subtilis TISTR 1415 (BS) as living biofilters for a subsequent biofertilizer activity. The optimal condition for nutrient recovery was at the 1:1 ratio of CV/BS using mixed guar gum/carrageenan (GG/CG) binders. After 7-day wastewater treatment, the living biofilters removed 86.
View Article and Find Full Text PDFIn this study, the exopolysaccharide from cyanobacteria was used for detoxification of acid hydrolysate of water hyacinth biomass. Exopolysaccharide-hydrogel showed phenolics and furans removal of 86 % and 97 %, respectively, with sugar recovery of 98.3 %.
View Article and Find Full Text PDFThe textiles for medical use and the purification of textile factory effluents have become the most crucial part of the human healthcare sector. In this study bioactive compounds produced by four distinct plant extracts were used for the synthesis of zinc oxide nanoparticles. The four different ZnO nanoparticles were comprehensively characterized by different analytical techniques.
View Article and Find Full Text PDFClay minerals such as Halloysite nanotubes (HNTs), abundantly available green nanomaterial, exhibit a significant advantage in biomedical applications such as drug delivery, antibacterial and antimicrobials, tissue engineering or regeneration, etc. Because of the mesoporous structure and high absorbability, HNTs exhibit great potential as a nanocarrier in drug delivery applications. The sulfuric acid treatment enhances the surface area of the HNTs and thereby improves their drug-loading capacity by enlarging their lumen space/inner diameter.
View Article and Find Full Text PDFThe photocatalytic nano-biohybrid systems have great potential for the conversion of solar energy to fermentative hydrogen production. Herein, a whole-cell nano-biohybrid system consisting of biosynthesized cadmium sulfide, Enterobacter aerogenes cells, and metal oxide nanoparticles was constructed. The system was encapsulated with sodium alginate and used for light-driven biohydrogen production under anaerobic and in the presence of oxygen conditions.
View Article and Find Full Text PDFVarious photoautotrophic cyanobacteria accumulate intracellular poly(3-hydroxybutyrate) (PHB) granules. This protocol can be used for determining the PHB contents of the cells as % PHB weight per dry cell weight using acid hydrolysis followed by high-performance liquid chromatography (HPLC). This HPLC analysis is rapid, with a running time of approximately 5 min per sample.
View Article and Find Full Text PDFWastewater treatment remains the most significant delinquent issue world-wide. Generally, wastewater treatment involves filtration followed by acidified de-emulsification through photocatalytic reduction. The aim of the present study is to reduce the use of nanoparticles in wastewater treatment and also to find an appropriate alternative to replace cotton fiber filters used in water treatment plant.
View Article and Find Full Text PDFPolyhydroxybutyrate (PHB) is a biocompatible and biodegradable polymer that has the potential to replace fossil-derived polymers. The enzymes involved in the biosynthesis of PHB are β-ketothiolase (PhaA), acetoacetyl-CoA reductase (PhaB), and PHA synthase (PhaC). PhaC in is the key enzyme for PHB production.
View Article and Find Full Text PDFThe unicellular halotolerant cyanobacterium is known as a potential hydrogen (H) producer. This study aimed to investigate the enhancement of H production under nutrient deprivation. The results showed that nitrogen and potassium deprivation induced dark fermentative H production by , while no differences in H production were found under sulfur and phosphorus deprivation.
View Article and Find Full Text PDFIn this study, an efficient microalgal strain SD07 was isolated from pond wastewater and identified as Scenedesmus sp. using the 18S rRNA gene sequence analysis. The strain SD07 was grown in a variety of concentrations (25-100%) of municipal wastewater.
View Article and Find Full Text PDFCyanobacteria accumulate polyglucan as main carbohydrate storage. Here, the cellular polyglucan content was determined in 27 cyanobacterial strains from 25 genera. The polyglucan contents were significantly enhanced in 20 and 23 strains under nitrogen (-N) and phosphate (-P) deprivation, respectively.
View Article and Find Full Text PDFBiological wastewater treatment is a promising and environmentally friendly method that utilises living microorganisms to remediate water and enable recovery or conversion of contaminants into valuable products. For many decades, microalgae and cyanobacteria, photosynthetic living microorganisms, have been explored extensively for wastewater bioremediation. They can be used for recovering valuable nutrients such as nitrogen and phosphorous from secondary effluents and capable of transforming those nutrients into marketable products such as biofuels, biofertilisers, nutraceutical, and pigments for promoting a Bio-Circular Green economy.
View Article and Find Full Text PDFTwo-stage cultivation is effective for glycogen production by cyanobacteria. Cells were first grown under adequate nitrate supply (BG11) to increase biomass and subsequently transferred to nitrogen deprivation (-N) to stimulate glycogen accumulation. However, the two-stage method is time-consuming and requires extensive energy.
View Article and Find Full Text PDFFront Bioeng Biotechnol
July 2022
The halotolerant cyanobacterium is a potential H producer that induces H evolution under nitrogen deprivation. H is mainly produced the catabolism of stored glycogen under dark anaerobic condition. H evolution is catalyzed by O-sensitive bidirectional hydrogenase.
View Article and Find Full Text PDFVarious photoautotrophic cyanobacteria increase the accumulation of bioplastic poly(3-hydroxybutyrate) (PHB) under nitrogen deprivation (-N) for energy storage. Several metabolic engineering enhanced cyanobacterial PHB accumulation, but these strategies are not applicable in non-gene-transformable strains. Alternatively, stimulating PHB levels by chemical exposure is desirable because it might be applied to various cyanobacterial strains.
View Article and Find Full Text PDFWorld-wide, an emerging demand is moving towards the biofuels to replace the fossil fuels. In alternative biofuel production strategies, cyanobacteria have unique characteristic of accumulating glycogen, lipid, and fuel molecules through natural mechanisms. Moreover, the cyanobacteria can be easily engineered to synthesis a plenty of fuel molecules from CO.
View Article and Find Full Text PDFMicroalgae have received much interest as a biofuel feedstock. However, the economic feasibility of biofuel production from microalgae does not satisfy capital investors. Apart from the biofuels, it is necessary to produce high-value co-products from microalgae fraction to satisfy the economic aspects of microalgae biorefinery.
View Article and Find Full Text PDFAlthough engineered cyanobacteria for the production of lipids and fatty acids (FAs) are intelligently used as sustainable biofuel resources, intracellularly overproduced FAs disturb cellular homeostasis and eventually generate lethal toxicity. In order to improve their production by enhancing FFAs secretion into a medium, we constructed three engineered 6803 strains including KA (a mutant lacking the gene), KAOL (KA overexpressing , encoding lipase A in membrane lipid hydrolysis), and KAOGR (KA overexpressing quadruple /, related to the CBB cycle). Certain contents of intracellular lipids and secreted FFAs of all engineered strains were higher than those of the wild type.
View Article and Find Full Text PDFIn the present study, fatty acid synthesis genes such as alpha and beta subunits of acetyl CoA carboxylase (accA and accD) were overexpressed in the glgC (Glucose-1-phosphate adenylyltransferase) knockout Synechocystis sp. PCC 6803. The biomass and lipid contents were evaluated in both the wild type and the engineered strains after copper treatment.
View Article and Find Full Text PDFIn photoautotrophic Synechocystis sp. PCC 6803, NADPH is generated from photosynthesis and utilized in various metabolism, including the biosynthesis of glyceraldehyde 3-phosphate (the upstream substrate for carbon metabolism), poly(3-hydroxybutyrate) (PHB), photosynthetic pigments, and hydrogen gas (H2). Redirecting NADPH flow from one biosynthesis pathway to another has yet to be studied.
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