L-theanine is an amino acid with a unique flavor and many therapeutic effects. Its enzymatic synthesis has been actively studied and γ-Glutamylmethylamide synthetase (GMAS) is one of the promising enzymes in the biological synthesis of theanine. However, the theanine biosynthetic pathway with GMAS is highly ATP-dependent and the supply of external ATP was needed to achieve high concentration of theanine production.
View Article and Find Full Text PDFIsobutanol is a potential biofuel, and its microbial production systems have demonstrated promising results. In a microbial system, the isobutanol produced is secreted into the media; however, the cells remaining after fermentation cannot be used efficiently during the isobutanol recovery process and are discarded as waste. To address this, we aimed to investigate the strategy of utilizing these remaining cells by combining the isobutanol production system with the indigo production system, wherein the product accumulates intracellularly.
View Article and Find Full Text PDFIndigo dye is an organic compound with a distinctive blue color. Most of the indigo currently used in industry is produced via chemical synthesis, which generates a large amount of wastewater. Therefore, several studies have recently been conducted to find ways to produce indigo eco-friendly using microorganisms.
View Article and Find Full Text PDFIdentification of novel, electricity-producing bacteria has garnered remarkable interest because of the various applications of electricigens in microbial fuel cell and bioelectrochemical systems. BBL25, an electricity-generating microorganism, uses various carbon sources and shows broader sugar utilization than the better-known MR-1. To determine the sugar-utilizing genes and electricity production and transfer system in BBL25, we performed an in-depth analysis using whole-genome sequencing.
View Article and Find Full Text PDFIn this study, fourteen types of biochar produced using seven biomasses at temperatures 300 °C and 600 °C were screened for phenolics (furfural and hydroxymethylfurfural (HMF)) removal. Eucheuma spinosum biochar (EB-BC 600) showed higher adsorption capacity to furfural (258.94 ± 3.
View Article and Find Full Text PDFPolyhydroxybutyrate (PHB) is a biodegradable bioplastic with potential applications as an alternative to petroleum-based plastics. However, efficient PHB production remains difficult. The main cost of PHB production is attributed to carbon sources; hence, finding inexpensive sources is important.
View Article and Find Full Text PDFPhasin is a surface-binding protein of polyhydroxyalkanoate (PHA) granules that is encoded by the phaP gene. As its expression increases, PHA granules become smaller, to increase their surface area, and are densely packed inside the cell, thereby increasing the PHA content. A wide range of PHA-producing bacteria have phaP genes; however, their PHA productivity differs, although they are derived from the cognate bacterial host cell.
View Article and Find Full Text PDFPolybutylene succinate (PBS) is a bioplastic substitute for synthetic plastics that are made from petroleum-based products such as polyethylene and polypropylene. However, the biodegradation rate of PBS is still low and similar to that of polylactic acid (PLA). Moreover, our knowledge about degrader species is limited to a few fungi and mixed consortia.
View Article and Find Full Text PDFUsing lignocellulosic biomass is immensely beneficial for the economical production of biochemicals. However, utilizing mixed sugars from lignocellulosic biomass is challenging because of bacterial preference for specific sugar such as glucose. Although previous studies have attempted to overcome this challenge, no studies have been reported on isobutanol production from mixed sugars in the Escherichia coli strain.
View Article and Find Full Text PDFPolyhydroxybutyrate (PHB) is a bio-based, biodegradable and biocompatible plastic that has the potential to replace petroleum-based plastics. Lignocellulosic biomass is a promising feedstock for industrial fermentation to produce bioproducts such as polyhydroxybutyrate (PHB). However, the pretreatment processes of lignocellulosic biomass lead to the generation of toxic byproducts, such as furfural, 5-HMF, vanillin, and acetate, which affect microbial growth and productivity.
View Article and Find Full Text PDFAs a biodegradable plastic, polyhydroxybutyrate (PHB) has relatively poor mechanical properties, preventing its wider use. Various plasticizers have been studied to improve the mechanical properties of PHB; however, due to the slow degradation speed in the soil environment and lack of evaluation methods, studies on the degradation of PHB with plasticizers are rarely reported. In this study, by applying sp.
View Article and Find Full Text PDFThe increasing interest in bioplastics, with regard to future environmental issues, has rendered research on bioplastic biodegradation highly important. However, only a few tools directly monitor the degradation of bioplastics without measuring the levels of gaseous products, such as carbon dioxide. Classical nonquantitative methods, such as clear zone tests on solid plates, and less-sensitive weight-loss experiments in liquid media measured using a precision scale, are still employed to screen the microbial players associated with bioplastic degradation and monitor the biodegradation rates.
View Article and Find Full Text PDFSphingobium yanoikuyae BBL01 can produce exopolysaccharides (EPS) and polyhydroxyalkanoates (PHAs). The effect of side products (furfural, hydroxymethylfurfural (HMF), vanillin, and acetate) produced during pretreatment of biomass was evaluated on S. yanoikuyae BBL01.
View Article and Find Full Text PDFThe present study deals with the utilization of lignocellulosic hydrolysate-based carbon source for exopolysaccharide (EPS) production using newly reported marine Echinicola sediminis BBL-M-12. This bacterium produced 7.56 g L and 5.
View Article and Find Full Text PDFMethicillin-resistant (MRSA) is a pathogenic bacterium that causes severe diseases in humans. For decades, MRSA has acquired substantial resistance against conventional antibiotics through regulatory adaptation, thereby posing a challenge for treating MRSA infection. One of the emerging strategies to combat MRSA is the combinatory use of antibacterial agents.
View Article and Find Full Text PDFMethicillin-resistant (MRSA) causes severe infections and poses a global healthcare challenge. The utilization of novel molecules which confer synergistical effects to existing MRSA-directed antibiotics is one of the well-accepted strategies in lieu of development of new antibiotics. Thymol is a key component of the essential oil of plants in the and .
View Article and Find Full Text PDFPolyhydroxybutyrate (PHB) is a potential substitute for plastics derived from fossil fuels, owing to its biodegradable and biocompatible properties. Lignocellulosic biomass could be used to reduce PHB production costs; however, the co-utilization of sugars, such as glucose and xylose, without catabolite repression is a difficult problem to be solved. Here, we selected a novel Loktanella sp.
View Article and Find Full Text PDFPoly(butylene adipate-co-terephthalate) (PBAT), a bioplastic consisting of aliphatic hydrocarbons and aromatic hydrocarbons, was developed to overcome the shortcomings of aliphatic and aromatic polyesters. Many studies report the use of PBAT as a blending material for improving properties of other bioplastics. However, there are few studies on microorganisms that degrade PBAT.
View Article and Find Full Text PDFPolyhydroxyalkanoates (PHAs) and their derivatives are biopolymers that have the potential of replacing petroleum-based plastics and can be produced and degraded via bacterial metabolism. However, there are only a few studies on polyhydroxybutyrate (PHB) production using lactate, one of the major waste organic acids that could be implemented in the production of polylactic acid (PLA). Herein, we screened and characterized the PHA-producing microbial strains isolated from saltern soil from Docho Island (South Korea).
View Article and Find Full Text PDFMorphology of foliar trichomes was analyzed in Quercus variabilis by electron microscopy and three-dimensional surface profiling. Leaves from suppressed or dominant sprouts of the oak species were collected after a forest fire to unravel the effects of the disturbance factor on sprouting of the oak species. Scanning electron microscopy revealed two types of trichomes depending on the leaf surface.
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