Lignin is the most important natural source of aromatic compounds. The valorisation of lignin into aromatics requires fractionation steps that can be catalysed by ligninolytic enzymes. However, one of the main limitations of biological lignin fractionation is the low efficiency of biocatalysts; it is therefore crucial to enhance or to identify new ligninolytic enzymes.
View Article and Find Full Text PDFPolyhydroxyalkanoates (PHAs) are bioplastics that can serve as substitutes for petroleum-based plastics with the advantages of being biodegradable, biocompatible, and biobased. The microbial production of polyhydroxyalkanoates is generally conducted in the presence of sugar mixes rich in monosaccharides. In this study, molecular and cultural approaches based on forest soils enriched with hydrocarbon complexes led to the identification and isolation of microbial strains affiliated with Paraburkholderia sp.
View Article and Find Full Text PDFis one of the most aggressive Botryosphaeriaceae species associated with grapevine trunk diseases. This species may secrete enzymes capable of overcoming the plant barriers, leading to wood colonization. In addition to their roles in pathogenicity, there is an interest in taking advantage of carbohydrate-active enzymes (CAZymes), related to plant cell wall degradation, for lignocellulose biorefining.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
January 2023
Lignocellulosic biomass is rich in lignins, which represent a bottomless natural source of aromatic compounds. Due to the high chemical complexity of these aromatic polymers, their biological fractionation remains challenging for biorefinery. The production of aromatics from the biological valorization of lignins requires the action of ligninolytic peroxidases and laccases produced by fungi and bacteria.
View Article and Find Full Text PDFStreptomyces coelicolor A3(2) is considered as the model strain among the Streptomyces and has the capacity to produce several natural molecules. Our hypothesis was that cultivation of the strain onto a complex carbon source such as wheat bran (WB) would induce the production of various secondary metabolites due to the presence of complex polysaccharides. A multiapproach has been performed in order to investigate: (1) whether that strain could degrade lignocellulose; (2) which enzymatic and metabolic pathways secondary were over-expressed when grown on WB.
View Article and Find Full Text PDFWe report a case of catecholamine-induced acute myocardial stunning that occurred in a six-year-old girl. This was triggered by an accidental noradrenaline injection during general anaesthesia for dental surgery. The clinical course was favourable, although cardiac enzymes and echocardiography were significantly altered.
View Article and Find Full Text PDFStrain RHZ10 was isolated from an oak rhizosphere sampled in Reims, France, and characterized to assess its taxonomy. Based on 16S rRNA gene sequence similarity, strain RHZ10 was affiliated to the genus and the closest species were NRRL B-2000 and ch24. Average nucleotide identity and digital DNA-DNA hybridization values were 77.
View Article and Find Full Text PDFThe microorganisms living on the phyllosphere (the aerial part of the plants) are in contact with the lignocellulosic plant cell wall and might have a lignocellulolytic potential. We isolated a Saccharibacillus strain (Saccharibacillus WB17) from wheat bran phyllosphere and its cellulolytic and hemicellulolytic potential was investigated during growth onto wheat bran. Five other type strains from that genus selected from databases were also cultivated onto wheat bran and glucose.
View Article and Find Full Text PDFThermobacillus xylanilyticus is a thermophilic and hemicellulolytic bacterium of interest for the production of thermostable hemicellulases. Enzymes' production by this bacterium is challenging, because the proliferation of a cheating subpopulation of cells during exponential growth impairs the production of xylanase after serial cultivations. Accordingly, a strategy of successive cultivations with cells transfers in stationary phase and the use of wheat bran and wheat straw as carbon sources were tested.
View Article and Find Full Text PDFThermobacillus xylanilyticus is a thermophilic and hemicellulolytic bacterium able to use several lignocelluloses as its main carbon source. This draft genome sequence gives insight into the genomic potential of this bacterium and provides new resources to understand the enzymatic mechanisms used by the bacterium during lignocellulose degradation and will allow the identification of robust lignocellulolytic enzymes.
View Article and Find Full Text PDFLignocellulose, the most abundant biomass on Earth, is a complex recalcitrant material mainly composed of three fractions: cellulose, hemicelluloses and lignins. In nature, lignocellulose is efficiently degraded for carbon recycling. Lignocellulose degradation involves numerous microorganisms and their secreted enzymes that act in synergy.
View Article and Find Full Text PDFThe phyllosphere, defined as the aerial parts of plants, is one of the most prevalent microbial habitats on earth. The microorganisms present on the phyllosphere can have several interactions with the plant. The phyllosphere represents then a unique niche where microorganisms have evolved through time in that stressful environment and may have acquired the ability to degrade lignocellulosic plant cell walls in order to survive to oligotrophic conditions.
View Article and Find Full Text PDFA bacterial strain, named For3, was isolated from forest soil sampled in Champenoux, France. Based on its 16S rRNA gene sequence, the strain was affiliated to the family and, more specifically, to the genus . The strain had 99.
View Article and Find Full Text PDFThe enzymatic production of xylo-oligosaccharides (XOs) from destarched wheat bran with a GH11 xylanase was studied. Xylo-oligosaccharides (XOs) produced were separated into different fractions according to their degree of polymerization (DP) and the nature of their substituents: arabinoxylo-oligosaccharides (AXOs) with a DP from 2 to 3 and DP from 2 to 6 and feruloylated arabinoxylo-oligosaccharides (FAXOs) esterified by ferulic and -coumaric acids with a DP from 3 to 6. Both AXOs (short and long DP) and FAXOs stimulated the growth of , , and similarly but not .
View Article and Find Full Text PDFInt J Syst Evol Microbiol
August 2021
A bacterial strain, arapr2, was isolated from agricultural soil sampled in Reims, France. Based on its 16S rRNA gene sequence, the strain was affiliated to the family and more specifically to the genus . The strain had 98.
View Article and Find Full Text PDFPigments are compounds with highly diverse structures and wide uses, which production is increasing worldwide. An eco-friendly method of bioproduction is to use the ability of some microorganisms to ferment on renewable carbon sources. Wheat bran (WB) is a cheap and abundant lignocellulosic co-product of low recalcitrance to biological conversion.
View Article and Find Full Text PDFAlkyl glycosides and sugars esters are non-ionic surfactants of interest for various applications (cosmetics, food, detergency,…). In the present study, xylans and cellulose from wheat bran were enzymatically converted into pentyl xylosides and glucose and xylose laurate monoesters. Transglycosylation reaction catalyzed by the commercial enzymatic cocktail Cellic Ctec2 in the presence of pentanol led to the synthesis of pentyl β-D-xylosides from DP1 to 3 with an overall yield of 520 mg/g of xylans present in wheat bran.
View Article and Find Full Text PDFLipase-catalyzed synthesis of xylo-oligosaccharides esters from pure xylobiose, xylotriose and xylotetraose in the presence of vinyl laurate was investigated. The influence of different experimental parameters such as the loading of lipase, the reaction duration or the use of a co-solvent was studied and the reaction conditions were optimized with xylobiose. Under the best conditions, a regioselective esterification occurred to yield a monoester with the acyl chain at the OH-4 of the xylose unit at the non-reducing end.
View Article and Find Full Text PDFHeat stress is an environmental factor that regularly challenges the well-being of living organisms. This study aims to examine the physiological changes happening in two reef-building coral species exposed to thermal stress under various light conditions. The two ecologically relevant heatwave scenarios were applied under ambient lights (high irradiance) and reduced light conditions (250 and < 10 μmol photons m s).
View Article and Find Full Text PDFMicrobiol Resour Announc
February 2020
The whole genome of sp. strain WB 17, a bacterial strain isolated from wheat phyllosphere, has been sequenced. This microorganism is equipped with several carbohydrate-active enzymes, which would explain its ability to fractionate lignocellulose.
View Article and Find Full Text PDFRoom Temperature Ionic Liquids (RTILs) pretreatment are well-recognized to improve the enzymatic production of platform molecules such as sugar monomers from lignocellulosic biomass (LCB). The conditions for implementing this key step requires henceforth optimization to reach a satisfactory compromise between energy saving, required RTIL amount and hydrolysis yields. Wheat bran (WB) and destarched wheat bran (DWB), which constitute relevant sugar-rich feedstocks were selected for this present study.
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