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Scientific Reports May 2023Several raw materials have been used as partial supplements or entire replacements for the main ingredients of kombucha to improve the biological properties of the...
Several raw materials have been used as partial supplements or entire replacements for the main ingredients of kombucha to improve the biological properties of the resulting kombucha beverage. This study used pineapple peels and cores (PPC), byproducts of pineapple processing, as alternative raw materials instead of sugar for kombucha production. Kombuchas were produced from fusions of black tea and PPC at different ratios, and their chemical profiles and biological properties, including antioxidant and antimicrobial activities, were determined and compared with the control kombucha without PPC supplementation. The results showed that PPC contained high amounts of beneficial substances, including sugars, polyphenols, organic acids, vitamins, and minerals. An analysis of the microbial community in a kombucha SCOBY (Symbiotic Cultures of Bacteria and Yeasts) using next-generation sequencing revealed that Acetobacter and Komagataeibacter were the most predominant acetic acid bacteria. Furthermore, Dekkera and Bacillus were also the prominent yeast and bacteria in the kombucha SCOBY. A comparative analysis was performed for kombucha products fermented using black tea and a fusion of black tea and PPC, and the results revealed that the kombucha made from the black tea and PPC infusion exhibited a higher total phenolic content and antioxidant activity than the control kombucha. The antimicrobial properties of the kombucha products made from black tea and the PPC infusion were also greater than those of the control. Several volatile compounds that contributed to the flavor, aroma, and beneficial health properties, such as esters, carboxylic acids, phenols, alcohols, aldehydes, and ketones, were detected in kombucha products made from a fusion of black tea and PPC. This study shows that PPC exhibits high potential as a supplement to the raw material infusion used with black tea for functional kombucha production.
Topics: Tea; Ananas; Beverages; Yeasts; Antioxidants; Camellia sinensis; Phenols; Anti-Infective Agents; Acetobacteraceae; Fermentation
PubMed: 37188725
DOI: 10.1038/s41598-023-34954-7 -
Archives of Microbiology Jul 2022Bacterial cellulose (BC) is a valuable biopolymer that is increasingly used in medical, pharmaceutical and food industries with its excellent physicochemical properties...
Optimization and physicochemical characterization of bacterial cellulose by Komagataeibacter nataicola and Komagataeibacter maltaceti strains isolated from grape, thorn apple and apple vinegars.
Bacterial cellulose (BC) is a valuable biopolymer that is increasingly used in medical, pharmaceutical and food industries with its excellent physicochemical properties as high water-holding capacity, nanofibrillar structure, large surface area, porosity, mechanical strength and biocompatibility. Accordingly, the isolation, identification and characterization of potent BC producers from grape, thorn apple and apple vinegars were performed in this study. The strains isolated from grape and apple vinegars were identified as Komagataeibacter maltaceti and the strain isolated from thorn apple vinegar was identified as Komagataeibacter nataicola with 16S rRNA analysis. Optimized conditions were found as 8% dextrin, 1.5% (peptone + yeast extract) and 10% inoculation amount at pH 6.0 with a productivity rate of 1.15 g/d/L, a yield of 8.06% and a dry weight of 6.45 g/L for K. maltaceti, and 10% maltose, 1% (peptone + yeast extract) and 10% inoculation amount at pH 6.0 with a productivity rate of 0.96 g/L/d, a yield of 5.35% and a dry weight of 5.35 g/L for K. nataicola. Obtained BC from K. maltaceti and K. nataicola strains was more than 2.56- and 1.86-fold when compared with BC obtained from HS media and exhibited 95.1% and 92.5% WHC, respectively. Based on the characterization results, BC pellicles show characteristic FT-IR bands and have ultrafine 3D structures with high thermal stability. By means of having ability to assimilate monosaccharides, disaccharides and polysaccharide used in this study, it is predicted that both isolated Komagataeibacter species can be used in the production of biopolymers from wastes containing complex carbon sources in the future.
Topics: Acetic Acid; Acetobacteraceae; Cellulose; Datura stramonium; Malus; Peptones; RNA, Ribosomal, 16S; Spectroscopy, Fourier Transform Infrared; Vitis
PubMed: 35802199
DOI: 10.1007/s00203-022-03083-6 -
Proceedings of the National Academy of... Feb 2022Bacteria are efficient colonizers of a wide range of secluded microhabitats, such as soil pores, skin follicles, or intestinal crypts. How the structural diversity of...
Bacteria are efficient colonizers of a wide range of secluded microhabitats, such as soil pores, skin follicles, or intestinal crypts. How the structural diversity of these habitats modulates microbial self-organization remains poorly understood, in part because of the difficulty to precisely manipulate the physical structure of microbial environments. Using a microfluidic device to grow bacteria in crypt-like incubation chambers of systematically varied lengths, we show that small variations in the physical structure of the microhabitat can drastically alter bacterial colonization success and resistance against invaders. Small crypts are uncolonizable; intermediately sized crypts can stably support dilute populations, while beyond a second critical length scale, populations phase separate into a dilute region and a jammed region. The jammed state is characterized by extreme colonization resistance, even if the resident strain is suppressed by an antibiotic. Combined with a flexible biophysical model, we demonstrate that colonization resistance and associated priority effects can be explained by a crowding-induced phase transition, which results from a competition between proliferation and density-dependent cell leakage. The emerging sensitivity to scale underscores the need to control for scale in microbial ecology experiments. Systematic flow-adjustable length-scale variations may serve as a promising strategy to elucidate further scale-sensitive tipping points and to rationally modulate the stability and resilience of microbial colonizers.
Topics: Acetobacter; Anti-Bacterial Agents; Bacteriological Techniques; Drug Resistance, Bacterial; Lab-On-A-Chip Devices; Tetracycline
PubMed: 35145031
DOI: 10.1073/pnas.2115496119 -
Plasmid Mar 2021The bacterium Oecophyllibacter saccharovorans of family Acetobacteraceae is a symbiont of weaver ant Oecophylla smaragdina. In our previous study, we published the...
The bacterium Oecophyllibacter saccharovorans of family Acetobacteraceae is a symbiont of weaver ant Oecophylla smaragdina. In our previous study, we published the finding of novel O. saccharovorans strains Ha5, Ta1 and Jb2 (Chua et al. 2020) but their plasmid sequences have not been reported before. Here, we demonstrate for the first time that the sole rrn operon of their genomes was detected on a 6.6 kb circular replicon. This replicon occurred in high copy number, much smaller size and lower G + C content than the main chromosome. Based on these features, the 6.6 kb circular replicon was regarded as rrn operon-containing plasmid. Further restriction analysis on the plasmids confirmed their circular conformation. A Southern hybridization analysis also corroborated the presence of 16S rRNA gene and thus the rrn operon on a single locus in the genome of the O. saccharovorans strains. However, similar genome architecture was not observed in other closely related bacterial strains. Additional survey also detected no plasmid-borne rrn operon in available genomes of validly described taxa of family Acetobacteraceae. To date, plasmid localization of rrn operon is rarely documented. This study reports the occurrence of rrn operon on the smallest bacterial plasmid in three O. saccharovorans strains and discusses its possible importance in enhancing their competitive fitness as bacterial symbiont of O. smaragdina.
Topics: Acetobacteraceae; Base Composition; Operon; Plasmids; RNA, Ribosomal, 16S
PubMed: 33476637
DOI: 10.1016/j.plasmid.2021.102559 -
Bioengineered Dec 2021Bacterial cellulose (BC) is higher in demand due to its excellent properties which is attributed to its purity and nano size. is a model organism where BC production... (Review)
Review
Bacterial cellulose (BC) is higher in demand due to its excellent properties which is attributed to its purity and nano size. is a model organism where BC production has been studied in detail because of its higher cellulose production capacity. BC production mechanism shows involvement of a series of sequential reactions with enzymes for biosynthesis of cellulose. It is necessary to know the mechanism to understand the involvement of regulatory proteins which could be the probable targets for genetic modification to enhance or regulate yield of BC and to alter BC properties as well. For the industrial production of BC, controlled synthesis is desired so as to save energy, hence genetic manipulation opens up avenues for upregulating or controlling the cellulose synthesis in the bacterium by targeting genes involved in cellulose biosynthesis. In this review article genetic modification has been presented as a tool to introduce desired changes at genetic level resulting in improved yield or properties. There has been a lack of studies on genetic modification for BC production due to limited availability of information on whole genome and genetic toolkits; however, in last few years, the number of studies has been increased on this aspect as whole genome sequencing of several strains are being done. In this review article, we have presented the mechanisms and the targets for genetic modifications in order to achieve desired changes in the BC production titer as well as its characteristics.
Topics: Acetobacteraceae; Cellulose; Genetic Engineering; Nanostructures
PubMed: 34519629
DOI: 10.1080/21655979.2021.1968989 -
ACS Biomaterials Science & Engineering Jul 2021Microcapsules made of synthetic polymers are used for the release of cargo in agriculture, food, and cosmetics but are often difficult to be degraded in the environment....
Microcapsules made of synthetic polymers are used for the release of cargo in agriculture, food, and cosmetics but are often difficult to be degraded in the environment. To diminish the environmental impact of microcapsules, we use the biofilm-forming ability of bacteria to grow cellulose-based biodegradable microcapsules. The present work focuses on the design and optimization of self-grown bacterial cellulose capsules. In contrast to their conventionally attributed pathogenic role, bacteria and their self-secreted biofilms represent a multifunctional class of biomaterials. The bacterial strain used in this work, , is able to survive and proliferate in various environmental conditions by forming biofilms as part of its lifecycle. Cellulose is one of the main components present in these self-secreted protective layers and is known for its outstanding mechanical properties. Provided enough nutrients and oxygen, these bacteria and the produced cellulose are able to self-assemble at the interface of any given three-dimensional template and could be used as a novel stabilization concept for water-in-oil emulsions. Using a microfluidic setup for controlled emulsification, we demonstrate that bacterial cellulose capsules can be produced with tunable size and monodispersity. Furthermore, we show that successful droplet stabilization and bacterial cellulose formation are functions of the bacteria concentration, droplet size, and surfactant type. The obtained results represent the first milestone in the production of self-assembled biodegradable cellulose capsules to be used in a vast range of applications such as flavor, fragrance, agrochemicals, nutrients, and drug encapsulation.
Topics: Capsules; Cellulose; Emulsions; Gluconacetobacter xylinus; Polymers
PubMed: 34190548
DOI: 10.1021/acsbiomaterials.1c00399 -
Carbohydrate Polymers Nov 2020Enzymatic glycosylation is an efficient way to increase the water solubility and the bioavailability of flavonoids. Levansucrases from Bacillus subtilis (Bs_SacB),...
Enzymatic glycosylation is an efficient way to increase the water solubility and the bioavailability of flavonoids. Levansucrases from Bacillus subtilis (Bs_SacB), Gluconacetobacter diazotrophicus (Gd_LsdA), Leuconostoc mesenteroides (Lm_LevS) and Zymomonas mobilis (Zm_LevU) were screened for puerarin (daidzein-8-C-glucoside) fructosylation. Gd_LsdA transferred the fructosyl unit of sucrose onto the glucosyl unit of the acceptor forming β-d-fructofuranosyl-(2→6)-puerarin (P1a), while Bs_SacB, Lm_LevS and Zm_LevU synthesized puerarin-4'-O-β-D-fructofuranoside (P1b) and traces of P1a. The Gd_LsdA product P1a was purified and assayed as precursor for the synthesis of puerarin polyfructosides (PPFs). Bs_SacB elongated P1a more competently forming a linear series of water-soluble PPFs reaching at least 21 fructosyl units, as characterized by HPLC-UV-MS, HPSEC and MALDI-TOF-MS. Simultaneous or sequential Gd_LsdA/Bs_SacB reactions yielded PPFs directly from puerarin with the acceptor conversion ranging 82-92 %. The bi-enzymatic cascade synthesis of PPFs in the same reactor avoided the isolation of the intermediate product P1a and it is appropriate for use at industrial scale.
Topics: Bacillus subtilis; Gluconacetobacter; Glycosylation; Hexosyltransferases; Hydrolysis; Isoflavones; Polysaccharides; Sucrose
PubMed: 32829838
DOI: 10.1016/j.carbpol.2020.116710 -
Plant and Soil 2022Despite little soil development and organic matter accumulation, lodgepole pine () consistently shows vigorous growth on bare gravel substrate of aggregate mining pits...
AIMS
Despite little soil development and organic matter accumulation, lodgepole pine () consistently shows vigorous growth on bare gravel substrate of aggregate mining pits in parts of Canadian sub-boreal forests. This study aimed to investigate the bacterial microbiome of lodgepole pine trees growing at an unreclaimed gravel pit in central British Columbia and suggest their potential role in tree growth and survival following mining activity.
METHODS
We characterized the diversity, taxonomic composition, and relative abundance of bacterial communities in rhizosphere and endosphere niches of pine trees regenerating at the gravel pit along with comparing them with a nearby undisturbed forested site using 16S rRNA high-throughput sequencing. Additionally, the soil and plant nutrient contents at both sites were also analyzed.
RESULTS
Although soil N-content at the gravel pit was drastically lower than the forest site, pine tissue N-levels at both sites were identical. Beta-diversity was affected by site and niche-type, signifying that the diversity of bacterial communities harboured by pine trees was different between both sites and among various plant-niches. Bacterial alpha-diversity was comparable at both sites but differed significantly between belowground and aboveground plant-niches. In terms of composition, pine trees predominantly associated with taxa that appear plant-beneficial including phylotypes of , , and at the gravel pit and , , and at the forest site.
CONCLUSIONS
Our results suggest that, following mining activity, regenerating pine trees recruit bacterial communities that could be plant-beneficial and support pine growth in an otherwise severely N-limited disturbed environment.
SUPPLEMENTARY INFORMATION
The online version contains supplementary material available at 10.1007/s11104-022-05327-2.
PubMed: 35698622
DOI: 10.1007/s11104-022-05327-2 -
Development (Cambridge, England) Aug 2021Perturbations to animal-associated microbial communities (the microbiota) have deleterious effects on various aspects of host fitness, but the molecular processes...
Perturbations to animal-associated microbial communities (the microbiota) have deleterious effects on various aspects of host fitness, but the molecular processes underlying these impacts are poorly understood. Here, we identify a connection between the microbiota and the neuronal factor Arc1 that affects growth and metabolism in Drosophila. We find that Arc1 exhibits tissue-specific microbiota-dependent expression changes, and that germ-free flies bearing a null mutation of Arc1 exhibit delayed and stunted larval growth, along with a variety of molecular, cellular and organismal traits indicative of metabolic dysregulation. Remarkably, we show that the majority of these phenotypes can be fully suppressed by mono-association with a single Acetobacter sp. isolate, through mechanisms involving both bacterial diet modification and live bacteria. Additionally, we provide evidence that Arc1 function in key neuroendocrine cells of the larval brain modulates growth and metabolic homeostasis under germ-free conditions. Our results reveal a role for Arc1 in modulating physiological responses to the microbial environment, and highlight how host-microbe interactions can profoundly impact the phenotypic consequences of genetic mutations in an animal host.
Topics: Acetobacter; Animals; Brain; Cytoskeletal Proteins; Drosophila; Homeostasis; Larva; Microbiota; Mutation; Nerve Tissue Proteins; Neurons; Phenotype
PubMed: 34323271
DOI: 10.1242/dev.195222 -
Nature Materials May 2021Biological systems assemble living materials that are autonomously patterned, can self-repair and can sense and respond to their environment. The field of engineered...
Biological systems assemble living materials that are autonomously patterned, can self-repair and can sense and respond to their environment. The field of engineered living materials aims to create novel materials with properties similar to those of natural biomaterials using genetically engineered organisms. Here, we describe an approach to fabricating functional bacterial cellulose-based living materials using a stable co-culture of Saccharomyces cerevisiae yeast and bacterial cellulose-producing Komagataeibacter rhaeticus bacteria. Yeast strains can be engineered to secrete enzymes into bacterial cellulose, generating autonomously grown catalytic materials and enabling DNA-encoded modification of bacterial cellulose bulk properties. Alternatively, engineered yeast can be incorporated within the growing cellulose matrix, creating living materials that can sense and respond to chemical and optical stimuli. This symbiotic culture of bacteria and yeast is a flexible platform for the production of bacterial cellulose-based engineered living materials with potential applications in biosensing and biocatalysis.
Topics: Acetobacteraceae; Cellulose; Coculture Techniques; Saccharomyces cerevisiae
PubMed: 33432140
DOI: 10.1038/s41563-020-00857-5