Publications by authors named "Jeong-Jun Yoon"

Poly(3-hydroxybutyrate) (PHB) is crucial for replacing petroleum-based plastics, an essential step towards fostering a bio-based economy. This shift is urgently needed to safeguard human health and preserve natural ecosystems. PHB is one of the most extremely commercialized bio-plastics.

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  • - Polyhydroxyalkanoate (PHA), particularly P(3HB--3HHx), is a bioplastic whose properties are influenced by the mole fraction of 3-hydroxyhexanoate (3HHx) but faces challenges in mass production due to complex fermentation conditions and strain development.
  • - To address production obstacles, researchers blended poly(3-hydroxybutyrate) (P(3HB)) with different 3HHx content films, assessing their molecular weight, thermal, mechanical, and degradability properties.
  • - The study found that these blended films maintained similar properties to microbial P(3HB--3HHx) and demonstrated a high degradation rate, suggesting that the simple blending method
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  • Researchers are tackling the low yield of polyhydroxyalkanoates (PHA) by exploring the use of δ-valerolactone (DVL) and plant oil to boost production without pre-treatment.
  • In their study, they found that PhaC enzyme effectively incorporated 5-hydroxyvalerate (5HV) into the PHA, resulting in significant biomass and synthesis during fed-batch fermentation.
  • The new PHAs showed improved properties, such as lower melting points and slower degradation rates, demonstrating potential benefits for polymer applications.
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  • Interest in bioplastics is increasing due to environmental pollution, particularly in polyhydroxyalkanoates (PHAs), which are produced by microorganisms.
  • The study screened Halomonas species for PHA production using affordable substrates like molasses and soybean flour, leading to the selection of Halomonas cerina YK44 for polyhydroxybutyrate (PHB) production.
  • Optimizing the medium showed the best PHB production conditions and revealed that PHB from the new substrates behaved similarly to that made from traditional sugars, although the presence of furfural negatively affected cell growth.
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Medium chain length Polyhydroxyalkanoate (mcl-PHA) is a biodegradable bioplastic material with promising applications in various fields, including the medical, packaging, and agricultural industries. This mcl-PHA can be biosynthesized by microorganisms from various carbon sources, and notably, it can also be produced from alkane mixtures contained in pyrolysis oil derived from low-grade waste plastics. In this study, Pseudomonas resinovorans was engineered to overexpress alkane monooxygenase from Lysinibaillus fusiformis JJY0216, enhancing its ability to utilize alkanes as carbon sources and thereby increasing mcl-PHA production.

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To alleviate environmental problems caused by using conventional plastics, bioplastics have garnered significant interest as alternatives to petroleum-based plastics. Despite possessing better degradability traits compared to traditional plastics, the degradation of bioplastics still demands a longer duration than initially anticipated. This necessitates the utilization of degradation strains or enzymes to enhance degradation efficiency, ensuring timely degradation.

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Polyhydroxybutyrate (PHB) is a well-known biodegradable bioplastic synthesized by microorganisms and can be produced from volatile fatty acids (VFAs). Among VFAs acetate can be utilized by Halomonas sp. YLGW01 for growth and PHB production.

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Polyhydroxyalkanoate (PHA) is one of the most promising materials for replacing petroleum-based plastics, and it can be produced from various renewable biomass sources. In this study, PHA production was conducted using Halomonas sp. YLGW01 utilizing mixed volatile fatty acids (VFAs) as carbon sources.

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The production cost of biodegradable polymer like polyhydroxybutyrate (PHB) is still higher than that of petroleum-based plastics. A potential solution for reducing its production cost is using a cheap carbon source and avoiding a process of sterilization. In this study, a novel PHB-producing microbial strain, Priestia sp.

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Macroalgae (seaweed) is considered a favorable feedstock for polyhydroxyalkanoates (PHAs) production owing to its high productivity, low land and freshwater requirement, and renewable nature. Among different microbes Halomonas sp. YLGW01 can utilize algal biomass-derived sugars (galactose and glucose) for growth and PHAs production.

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Isobutanol 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.

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Petrochemical-based plastics are hardly biodegradable and a major cause of environmental pollution, and polyhydroxybutyrate (PHB) is attracting attention as an alternative due to its similar properties. However, the cost of PHB production is high and is considered the greatest challenge for its industrialization. Here, crude glycerol was used as a carbon source for more efficient PHB production.

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Identification 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.

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Coffee waste is an abundant biomass that can be converted into high value chemical products, and is used in various renewable biological processes. In this study, oil was extracted from spent coffee grounds (SCGs) and used for polyhydroxyalkanoate (PHA) production through . The oil-extracted SCGs (OESCGs) were hydrolyzed and used for biohydrogen production through DSM10702.

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Polyhydroxybutyrate (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.

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Polyhydroxybutyrate (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.

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As 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.

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Leaching of cobalt and nickel into diverse water streams has become an environmental hazard and is continuously impacting human health through the food chain. Solvent extraction is the most widely accepted for separating these metals, but traditional extractants employed in conjunction with molecular diluents often lack selectivity and caused major environmental hurdles. Therefore, the development of cost-effective, environmentally friendly technologies for recovering these heavy metals has been strongly encouraged in recent years.

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Article Synopsis
  • Polyhydroxyalkanoate (PHA) is a biodegradable plastic that can replace traditional petroleum-based plastics and can have elastomeric properties when produced as medium-chain-length PHA (mcl-PHA).
  • In the study, researchers screened different alkanes as carbon sources to produce mcl-PHA, finding that using a mixture of n-octane, n-decane, and n-dodecane produced more PHA (0.74 g/L) than using them individually.
  • The researchers found an optimal alkane ratio for maximum production and determined ideal nitrogen and phosphorus concentrations, ultimately achieving 2.1 g/L of mcl-PHA in a fermenter under these optimized conditions.
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The 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.

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A conductive metal compound can be used as a catalyst for enhancing hydrogen production by dark fermentation. This study aimed to identify mechanisms of enhanced hydrogen production by magnetite supplementation. Experiments were performed with lactate and/or magnetite supplementation to confirm that the lactate-utilizing pathway is the key cause of enhanced hydrogen production.

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Polyhydroxybutyrate (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.

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Gamma-aminobutyric acid (GABA) is a non-proteinogenic amino acid act as a major neurotransmitter inhibitor in the nervous system of mammals. It also used as a precursor of bioplastics synthesis such as N-methylpyrolidone and polyamide 4. Chemical-based synthesis methods have many environmental-related issues, so efforts have been made to develop biosynthetic methods to produce GABA.

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Polyhydroxyalkanoates (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).

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Article Synopsis
  • Cellulosic ethanol is gaining global interest as a sustainable transportation fuel due to its potential carbon benefits, but current production faces significant challenges.
  • Major issues include variability in feedstock, natural resistance, and the absence of cost-effective processing methods, hindering the sustainability of biorefineries.
  • Key solutions involve research advancements in biomass pretreatment, fermentation techniques, and the need for efficient methods and economic analysis to ensure the viability of cellulosic ethanol as a fuel source.
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