RESUMO
Synbiotics are complex preparations of prebiotics that can be selectively utilized by live microorganisms to improve host health. Synbiotics are divided into complementary synbiotics, which consist of probiotics and prebiotics with independent functions, and synergistic synbiotics, which consist of prebiotics that are selectively used by gut microorganisms. Complementary synbiotics used in human clinical trials include Lactobacillus spp. and Bifidobacterium spp. as probiotics, and fructooligosaccharides, galactooligosaccharides, and inulin as prebiotics. Over the past five years, synbiotics have been most commonly used in patients with metabolic disorders, including obesity, and immune and gastrointestinal disorders. Several studies have observed alterations in the microbial community; however, these changes did not lead to significant improvements in disease outcomes or biochemical and hematological markers. The same synbiotics have been applied to individuals with different gut environments. As a result, even with the same synbiotics, there are non-responders who do not respond to the applied synbiotics due to the different intestinal environment for each individual. Therefore, to obtain meaningful results, applying different synbiotics depending on the individual is necessary. Synergistic synbiotics are one solution to circumvent this problem, as they combine elements that can effectively improve health, even in non-responders. This review aims to explain the concept of synbiotics, highlight recent human clinical trials, and explore the current state of research on synergistic synbiotics.
Assuntos
Microbioma Gastrointestinal , Promoção da Saúde , Prebióticos , Probióticos , Simbióticos , Humanos , Promoção da Saúde/métodos , Gerenciamento Clínico , Oligossacarídeos/metabolismo , Bifidobacterium/metabolismo , Lactobacillus/metabolismo , Obesidade/terapia , Gastroenteropatias/microbiologia , Gastroenteropatias/terapiaRESUMO
Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation, aberrant differentiation of keratinocytes, and dysregulated immune responses. WW domain-containing oxidoreductase (WWOX) is a non-classical tumor suppressor gene that regulates multiple cellular processes, including proliferation, apoptosis, and migration. This study aimed to explore the possible role of WWOX in the pathogenesis of psoriasis. Immunohistochemical analysis showed that the expression of WWOX was increased in epidermal keratinocytes of both human psoriatic lesions and imiquimod-induced mice psoriatic model. Immortalized human epidermal keratinocytes were transduced with a recombinant adenovirus expressing microRNA specific for WWOX to downregulate its expression. Inflammatory responses were detected using Western blotting, real-time quantitative reverse transcription polymerase chain reaction (PCR), and enzyme-linked immunosorbent assay. In human epidermal keratinocytes, WWOX knockdown reduced nuclear factor-kappa B signaling and levels of proinflammatory cytokines induced by polyinosinic: polycytidylic acid [(poly(I:C)] in vitro. Furthermore, calcium chelator and protein kinase C (PKC) inhibitors significantly reduced poly(I:C)-induced inflammatory reactions. WWOX plays a role in the inflammatory reaction of epidermal keratinocytes by regulating calcium and PKC signaling. Targeting WWOX could be a novel therapeutic approach for psoriasis in the future.
Assuntos
Dermatite , Psoríase , Animais , Humanos , Camundongos , Modelos Animais de Doenças , Inflamação , NF-kappa B , Psoríase/induzido quimicamente , Psoríase/genética , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genéticaRESUMO
Glycosyltransferase-producing Leuconostoc lactis CCK940 produces CCK- oligosaccharides, gluco-oligosaccharide molecules, using sucrose and maltose as donor and acceptor molecules, respectively. In this study, the immunostimulatory activities of CCK-oligosaccharides on RAW264.7 macrophages and BALB/c mice were evaluated. CCK-oligosaccharides induced the expression of phosphorylated-p38, extracellular-signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) and upregulation of phagocytic activity in RAW264.7 macrophages, suggesting their involvement in mitogen-activated protein kinase (MAPK) signaling pathway and phagocytosis. When CCK-oligosaccharides were administered to mice intraperitoneally injected with cyclophosphamide (CY), spleen indices and expressions of interleukin (IL)-6, IL-10, and tumor necrosis factor-α increased, compared with those in only CY-treated group. These findings suggest that CCK-oligosaccharides can be used as an effective immunostimulating agent.
Assuntos
Leuconostoc/metabolismo , Oligossacarídeos/farmacologia , Animais , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Imunização/métodos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
Leuconostoc lactis CCK940, which exhibits glycosyltransferase activity, produces oligosaccharides using sucrose and maltose as donor and receptor molecules, respectively. The oligosaccharides produced were purified by Bio-gel P2 chromatography and the purified oligosaccharides (CCK-oligosaccharides) consisted of only glucose. 1H-NMR analysis revealed that the CCK-oligosaccharides were composed of 77.6% α-1,6 and 22.4% α-1,4 glycosidic linkages, and the molecular weight of the CCK-oligosaccharides was found to be 9.42 × 102 Da. To determine the prebiotic effect of the CCK-oligosaccharides, various carbon sources were added in modified media. Growth of six probiotic strains, Lactobacillus casei, L. pentosus, L. plantarum, Weissella cibaria, Bifidobacterim animalis, and Saccharomyces cerevisiae, was better when the CCK-oligosaccharides were used as the sole carbon source compared to fructo-oligosaccharides, which are widely used as prebiotics. These results showed that the CCK-oligosaccharides produced from Leu. lactis CCK940 could serve as good candidates for novel prebiotics.
Assuntos
Leuconostoc/metabolismo , Oligossacarídeos/química , Bifidobacterium/metabolismo , Fermentação/fisiologia , Lactobacillus/metabolismo , Maltose/química , Prebióticos , Probióticos/química , Sacarose/químicaRESUMO
In the present study, 35 Leuconostoc mesenteroides strains isolated from vegetables and food products from South Korea were studied by multilocus sequence typing (MLST) of seven housekeeping genes (atpA, groEL, gyrB, pheS, pyrG, rpoA, and uvrC). The fragment sizes of the seven amplified housekeeping genes ranged in length from 366 to 1414 bp. Sequence analysis indicated 27 different sequence types (STs) with 25 of them being represented by a single strain indicating high genetic diversity, whereas the remaining 2 were characterized by five strains each. In total, 220 polymorphic nucleotide sites were detected among seven housekeeping genes. The phylogenetic analysis based on the STs of the seven loci indicated that the 35 strains belonged to two major groups, A (28 strains) and B (7 strains). Split decomposition analysis showed that intraspecies recombination played a role in generating diversity among strains. The minimum spanning tree showed that the evolution of the STs was not correlated with food source. This study signifies that the multilocus sequence typing is a valuable tool to access the genetic diversity among L. mesenteroides strains from South Korea and can be used further to monitor the evolutionary changes.
Assuntos
Variação Genética , Leuconostoc mesenteroides/genética , Verduras/microbiologia , Microbiologia de Alimentos , Leuconostoc mesenteroides/classificação , Tipagem de Sequências Multilocus , Filogenia , República da Coreia , Análise de Sequência de DNARESUMO
Production of oligosaccharides from Leuconostoc lactis CCK940 was optimized using a response surface methodology with a central composite design. Culture temperature and the concentrations of sucrose and maltose were used as the main factors. The predicted optimum conditions for the production of oligosaccharides were a culture temperature of 30 °C, a sucrose concentration of 9.6% (w/v), and a maltose concentration of 7.4% (w/v). Using these optimal conditions, Leuconostoc lactis CCK940 was cultured using a fermenter to produce oligosaccharides, and the resulting oligosaccharides with a degree of polymerization greater than 4 were purified by Bio-gel P2 gel permeation column chromatography and then lyophilized. When macrophages were treated with the purified oligosaccharides at concentrations of 0.1â»10 mg/mL, no cytotoxicity towards the macrophages was observed. However, nitric oxide production levels were similar to those following treatment with 1 µg/mL lipopolysaccharide. The mRNA expression levels of tumor necrosis factor-α, interleukin-1ß, interleukin-6, and inducible nitric oxide synthase were all also increased in a dose-dependent manner following treatment with the oligosaccharides. These data suggest that oligosaccharides produced by Leuconostoc lactis CCK940 could be used as an immune enhancer of macrophages.
Assuntos
Leuconostoc/metabolismo , Macrófagos/efeitos dos fármacos , Oligossacarídeos/metabolismo , Oligossacarídeos/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Interleucina-1beta/genética , Interleucina-6/genética , Macrófagos/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxidos de Nitrogênio/metabolismo , Células RAW 264.7 , RNA Mensageiro/genética , Temperatura , Fator de Necrose Tumoral alfa/genéticaRESUMO
For the fermentation of vinegar using onion, acetic acid bacteria and yeast strains with high fermentation ability were screened. Among them, Saccharomyces cerevisiae 1026 was selected as a starter for ethanol production and Acetobacter orientalis MAK88 was selected as a vinegar producer. When the two-stage fermentation of onion vinegar was performed at 28 °C, the titratable acidity reached 4.80% at 24 h of fermentation. When semi-continuous fermentation proceeded to charge-discharge consisting of three cycles, the acetic acid content reached 4.35% at 48 h of fermentation. At this stage, the fermentation efficiency, acetic acid productivity, and specific product formation rate were 76.71%, 17.73 g/(L·d), and 20.58 g/(g·h), respectively. The process in this study significantly reduced the fermentation time and simplified the vinegar production process. The content of total flavonoids and total polyphenols in onion vinegar were 104.36 and 455.41 µg/mL, respectively. The antioxidant activities of onion vinegar in terms of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTSâº) radical scavenging activity, and reducing power were 75.33%, 98.88%, and 1.28, respectively. The nitrite scavenging abilities of onion vinegar were 95.38 at pH 1.2. The onion vinegar produced in this study showed higher organoleptic acceptability than commercial onion vinegar.
Assuntos
Ácido Acético/química , Ácido Acético/metabolismo , Fermentação , Cebolas/metabolismo , Ácido Acético/análise , Ácido Acético/farmacologia , Antioxidantes/análise , Antioxidantes/química , Bactérias/metabolismo , Reatores Biológicos , Compostos de Bifenilo/antagonistas & inibidores , Compostos de Bifenilo/química , Etanol/metabolismo , Flavonoides/análise , Flavonoides/química , Microbiologia de Alimentos , Nitritos/antagonistas & inibidores , Nitritos/química , Picratos/antagonistas & inibidores , Picratos/química , Polifenóis/análise , Polifenóis/química , Saccharomyces cerevisiae/metabolismo , Fluxo de TrabalhoRESUMO
Soybean-derived peptides exert several beneficial effects in various experimental models. However, only a few studies have focused on the radical scavenging and anti-wrinkle effects of soymilk-derived peptides produced via different processes, such as fermentation, enzymatic treatment, and ultrafiltration. Therefore, in this study, we investigated the radical scavenging and antiwrinkle effects of soymilk fractions produced using these processes. We found that 50SFMKUF5, a 5 kDa ultrafiltration fraction fermented with Lacticaseibacillus paracasei MK1 after flavourzyme treatment, exhibited the highest radical scavenging activity using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay as well as potent anti-wrinkle effects assessed by type 1 procollagen production and tumor necrosis factor-α production in ultraviolet B (UVB)-treated human dermal fibroblasts and HaCaT keratinocytes. To identify potential bioactive peptides, candidate peptides were synthesized, and their anti-wrinkle effects were assessed. APEFLKEAFGVN (APE), palmitoyl-APE, and QIVTVEGGLSVISPK peptides were synthesized and used to treat UVB-irradiated fibroblasts, HaCaT keratinocytes, and α-melanocyte-stimulating hormone-induced B16F1 melanoma cells. Among these peptides, Pal-APE exerted the strongest effect. Our results highlight the potential of soymilk peptides as anti-aging substances.
RESUMO
Lactobacillus johnsonii 7409N31 was isolated from the feces of a healthy 11-day-old Hanwoo calf from a farm in Geochang-gun, Gyeongsangnam-do, Korea. The genome of the strain was completely sequenced using the PacBio RSII sequencing system, and it was confirmed that it was composed of one circular chromosome. The size of the entire genome was 2,198,442 bp, and it had 35.01 mol% guanine + cytosine (G + C) content and 2,222 protein-coding sequences, 24 rRNA, 3 ncRNA, and 112 tRNA genes. Strain 7409N31 possessed genes encoding enzymes involved in the hydrolysis of both fibrous and non-fibrous carbohydrates. These data provide a comprehensive theoretical understanding for developing industrial probiotic feed additives that improve nutrient digestibility.
RESUMO
Atopic dermatitis (AD) is characterized by chronic, relapsing, pruritic inflammatory skin disease. Adiponectin has been reported to have anti-inflammatory effects not only on metabolic disorders but also on various inflammatory disorders. The study aimed to validate adiponectin as a potential biomarker for AD disease severity and treatment response. Seventy-five patients with AD and 28 healthy volunteers were enrolled in the study. Patient information, including Eczema Area and Severity Index (EASI) scores and pruritus numeric rating scales (NRSs), were collected. An enzyme linked immunosorbent assay (ELISA) was conducted to measure levels of serum adiponectin. Additionally, sera of patients treated with dupilumab were collected and measured at 16 and 52 weeks from baseline. Serum adiponectin levels were significantly lower in moderate and severe AD patients than in the control and mild AD patients. Serum adiponectin level was negatively correlated with the EASI score and pruritus NRS. However, no significant changes were observed according to biologic treatment for AD. Low serum adiponectin levels are associated with moderate to severe AD, suggesting a potential role for adiponectin as a biomarker for severity assessment of AD.
RESUMO
A high-fat diet (HFD) induces low-grade, chronic inflammation throughout the body including the hypothalamus, a key brain region involved in the control of satiety and energy expenditure in central nervous system (CNS). Kimchi is a traditional fermented Korean food, which is recognized as a healthy food. In this study, we evaluated its ability to suppress the obesity-induced inflammation in mice fed an HFD. Male C57BL/6 mice were fed an HFD or HFD with kimchi (pH 5.2 â¼ 5.8). Oral administration of kimchi significantly reduced the body weight, fat mass gain, and levels of pro-inflammatory cytokines in serum. Furthermore, kimchi diminished the HFD-induced activation of astrocyte and microglial cells (reactive gliosis, a hallmark of CNS injury and inflammation) in hypothalamus region. IgG accumulation assay showed that kimchi ingestion suppressed HFD-induced breakage of the blood brain barrier (BBB) via upregulating the expression of tight junction molecules in cerebrovascular endothelial cells. In addition, kimchi modulated gut microbiome profiles, which showed an increase in the abundance of Akkermansia muciniphila. Moreover, kimchi enhanced acetate level and BBB integrity in A. muciniphila-colonized gnotobiotic mice. These results suggest that kimchi may exert beneficial effects to prevent and ameliorate obesity and associated neuroinflammation by changing gut microbiota composition and short-chain fatty acids production.
Assuntos
Eixo Encéfalo-Intestino , Alimentos Fermentados , Animais , Células Endoteliais/metabolismo , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias , Obesidade/prevenção & controleRESUMO
Water soluble propolis was prepared using ß-cyclodextrin, and its effect on an ethanol-induced hangover was examined in Sprague-Dawley (SD) rats fed with ethanol. When SD rats were administrated with propolis 30 min after ethanol feeding, ethanol content in the rat serum decreased 2.1 times 1 h after ethanol feeding. Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in rat liver increased 3.0 and 4.4 times, respectively, 1 h after ethanol feeding and administration of propolis 30 min after ethanol feeding. There were no differences in the expression of ADH and ALDH genes regardless of propolis administration. These results indicated that a decrease in ethanol content in the serum was not due to an increase in the expression of ADH or ALDH genes but rather, an increase in activities of ADH and ALDH.
RESUMO
Identification and classification of beneficial microbes is of the highest significance in food science and related industries. Conventional phenotypic approaches pose many challenges, and they may misidentify a target, limiting their use. Genotyping tools show comparatively better prospects, and they are widely used for distinguishing microorganisms. The techniques already employed in genotyping of lactic acid bacteria (LAB) are slightly different from one another, and each tool has its own advantages and disadvantages. This review paper compiles the comprehensive details of several fingerprinting tools that have been used for identifying and characterizing LAB at the species, sub-species, and strain levels. Notably, most of these approaches are based on restriction digestion, amplification using polymerase chain reaction, and sequencing. Nowadays, DNA sequencing technologies have made considerable progress in terms of cost, throughput, and methodology. A research journey to develop improved versions of generally applicable and economically viable tools for fingerprinting analysis is ongoing globally.
RESUMO
The objective of this study was to track intentionally inoculated Leuconostoc mesenteroides (11251) and Lactobacillus brevis (B151) strains in kimchi using random amplified polymorphic DNA (RAPD), repetitive element palindromic PCR (rep-PCR), and comparative housekeeping gene sequences analysis. The 16S rRNA gene provided species-level information for 30 colonies randomly picked from kimchi inoculated with strains 11251 and B151. Out of 30 colonies, one colony was matched to strain 11251, and two colonies were found identical to strain B151 reference strain in inoculated kimchi. Notably, among the three tools, strain 11251 was best tracked by comparative gene sequence analysis, while strain B151 tracked by all three tools. Our results suggest that the gene sequence analysis is a more reliable tool for tracking of desired strains than RAPD and rep-PCR. Based on the findings, it is recommended that gene sequence analysis could be used to avoid misuse of industrially useful strains within the growing food industry.
RESUMO
The present work aimed at tracking intentionally inoculated lactic acid bacteria (LAB) strains in yogurt and probiotic powder. Leuconostoc (Leu.) mesenteroides (11251), Lactobacillus (L.) brevis (B151), and Lactobacillus plantarum (LB41K) strains were tracked in yogurt, and L. plantarum (LB41P) was tracked in a commercial probiotic powder. The yogurt was intentionally inoculated with the selected bacterial strains. Two types of yogurt with known and unknown bacterial pools were utilized. The standard 16S rRNA gene sequencing was used to evaluate the initial screening. The molecular typing tools, random amplified polymorphic DNA (RAPD), repetitive element palindromic PCR (rep-PCR), and comparative gene sequence analysis of selected housekeeping loci were used to track the inoculated dubious strains. Out of 30 random selections for each inoculation, the developed method identified seven (11251), nine (B151), and five (LB41K) colonies in the yogurt. The validation was performed by identifying 7 colonies (LB41P) out of 30 in the probiotic powder. The DNA banding profiles and the gene sequence alignments led to the identification of the correct inoculated strains. Overall, the study summarizes the use of molecular tools to identify the deliberately inoculated LAB strains. In conclusion, the proposed polyphasic approach effectively tracked the intentionally inoculated strains: Leu. mesenteroides, L. brevis, and L. plantarum (LB41K) in yogurt and L. plantarum (LB41P) in probiotic powder. The study demonstrates how to track industrially relevant misused LAB strains in marketable food products.
RESUMO
Lactobacillus brevis is a part of a large family of lactic acid bacteria that are present in cheese, sauerkraut, sourdough, silage, cow manure, feces, and the intestinal tract of humans and rats. It finds its use in food fermentation, and so is considered a "generally regarded as safe" organism. L. brevis strains are extensively used as probiotics and hence, there is a need for identifying and characterizing these strains. For identification and discrimination of the bacterial species at the subspecific level, repetitive element-polymerase chain reaction method is a reliable genomic fingerprinting tool. The objective of the present study was to characterize 13 strains of L. brevis isolated from various fermented foods using repetitive element-polymerase chain reaction. Repetitive element-polymerase chain reaction was performed using three primer sets, REP, Enterobacterial Repetitive Intergenic Consensus (ERIC), and (GTG)5, which produced different fingerprinting patterns that enable us to distinguish between the closely related strains. Fingerprinting patterns generated band range in between 150 and 5000 bp with REP, 200-7500 bp with ERIC, and 250-2000 bp with (GTG)5 primers, respectively. The Jaccard's dissimilarity matrices were used to obtain dendrograms by the unweighted neighbor-joining method using genetic dissimilarities based on repetitive element-polymerase chain reaction fingerprinting data. Repetitive element-polymerase chain reaction proved to be a rapid and easy method that can produce reliable results in L. brevis species.
Assuntos
Alimentos Fermentados/microbiologia , Levilactobacillus brevis/classificação , Levilactobacillus brevis/isolamento & purificação , Tipagem Molecular , Sequências Repetitivas de Ácido Nucleico , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , DNA Bacteriano/genética , Microbiologia de Alimentos , Reação em Cadeia da Polimerase , República da Coreia , Especificidade da EspécieRESUMO
The objective of this study was to perform genetic diversity analysis of 13 strains isolated from South Korean foods by multilocus sequence typing (MLST). For typing, seven housekeeping loci (atpA, dnaA, dnaK, gyrB, pheS, pyrG, and rpoA) were selected, amplified and analyzed. Fifty-one polymorphic sites varying from 1 to 22 in each species were identified. Thirteen sequence types were generated with allele numbers ranged from 2 to 10. The overall relationship between strains was assessed by unweighted pair group method with arithmetic mean dendrogram and minimum spanning tree. In addition, combined spits tree analysis revealed intragenic recombination. No clear relationship was observed between the isolation sources and strains. The developed MLST scheme enhanced our knowledge of the population diversity of Leu. citreum strains and will be used further for the selection of industrially important strain.
RESUMO
To identify and discriminate the bacterial species at the subspecific level, rep-PCR is a reliable genomic fingerprinting tool. Fourteen strains of bacteria were isolated from different food sources, identified as Leuconostoc citreum using 16S rRNA gene sequencing, and amplified using rep-primers (REP, ERIC, and (GTG)5). Fingerprinting patterns generated bands in the range of 300-6,000 bp with REP, 150-6,000 bp with ERIC, and 200-1,700 bp with (GTG)5 primers. In UPGMA dendrogram analysis, 14 strains were clustered into three clades (I, II, and III) with all the primers, thus differentiating them at the molecular level. The present study revealed the differentiation of L. citreum strains using rep-PCR.
Assuntos
Impressões Digitais de DNA/métodos , Alimentos Fermentados/microbiologia , Leuconostoc/genética , Leuconostoc/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Sequências Repetitivas de Ácido Nucleico/genética , Técnicas de Tipagem Bacteriana , Sequência de Bases , Primers do DNA/genética , DNA Bacteriano/genética , Microbiologia de Alimentos , Genes Bacterianos , Leuconostoc/classificação , Tipagem Molecular/métodos , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Especificidade da EspécieRESUMO
Lactic acid bacteria are known for their preservative effects on food products like meat and sausage. Since they are related to humans, these bacteria require proper characterization and identification among various other bacteria in the surroundings. For their identification, several typing methods have already been applied of which the genotyping methods provide reproducible and unambiguous results. In this study, PCR-based method called repetitive element PCR was used for typing 37 Leuconostoc mesenteroides with three primers, REP, ERIC, and (GTG)5, annealing to repetitive sequences present in the bacterial genome. Different fingerprints were obtained for the isolates showing distinguishing profiles. Further phylogenetic analysis was performed using UPGMA method of clustering which provided proper identification with genetic relatedness of all the isolates. It was finally observed that, out of the three primers used, (GTG)5 discriminated the strains precisely than the other two.
RESUMO
To produce onion vinegar with high efficiency, various fermentation conditions, such as varying initial ethanol concentrations and the addition of ethanol or onion juice were optimized. Acetobacter tropicalis KFCC 11476P consumed ethanol at a rate of 0.125-0.140 g/h when the initial ethanol concentrations were 4, 5, and 6%, and the acidity of the fermentation broth reached the maximum level when the ethanol was completely starved. In the case of fed-batch fermentation with continuous feeding, when a small amount of ethanol and onion juice was continuously supplied into the broth after 30 h of fermentation, the acidity continued to increase up to 4.5% at 45 h. All the while, the remaining ethanol content of the fermentation broth was 1.13-1.69%. The maximum acidity of onion vinegar in the pilot-scale fermenter reached 4.6% at 48 h of which fermentation speed was five times faster than the general standard.