Animal experiments have demonstrated the effectiveness of fermented rice germ and soybean extracts in lowering blood alcohol concentration. A compound primarily derived from fermented soybean extract constitutes the principal component of DA-5521, an experimental dietary substance examined in this study. We investigated the possible hangover-alleviating effects of DA-5521 in individuals aged 19 to 50 who had previously experienced hangovers. Moreover, we enrolled 22 participants who met the eligibility criteria and conducted a double-blind, randomized, placebo-controlled crossover trial. Six hours after alcohol consumption, the test group exhibited a statistically significant reduction in blood acetaldehyde concentration compared with the placebo group. Further, our results displayed significantly lower levels in the DA- 5521 group at 0.50 and 0.75 h post-ingestion and substantially lower peak breath alcohol concentration compared to the placebo group. These findings confirm that consumption of DA-5521 can significantly ameliorate hangover symptoms by diminishing blood acetaldehyde concentration and reduce breath alcohol concentration.
1-Deoxynojirimycin (DNJ), an alpha-glucosidase inhibitor, has been used to prevent or treat type 2 diabetes. Low amounts of DNJ are found in mulberry leaf; however, a methodology is necessary to enhance the DNJ content of mulberry leaf extract (MLE) since increasing the amounts of DNJ is required for the prevention and treatment of type 2 diabetes. In this study, the DNJ content of MLE was increased through the optimization of the conditions for MLE fermentation by Lactobacillus plantarum SG-053, using response surface methodology (RSM). By single factor testing, the optimal conditions were identified as an inoculum concentration of 1%(v/v), an MLE concentration of 3°Bx, and no agitation. Based on a Plackett-Burman design, the following factors were considered to majorly affect the DNJ content in the MLE fermentation product: the initial pH, fermentation temperature, and fermentation time. By response surface methodology, the optimal conditions for MLE fermentation was found to have an initial pH of 5.5, a fermentation temperature of 31.9oC, and a fermentation time of 34 h. Under these optimal fermentation conditions, the DNJ content in MLE increased 3.59 times, or from 23.85 to 85.54 μg/mL.
본 연구에서는 메주에서 분리된 C. allociferrii JNO301 을 이용한 최적 홍삼 ginsenosides의 생물전환 조건을 확인한 결과, 1.0% (v/v)의 홍삼 추출물에 탄소원으로서 2.5%(w/ v)의 galactose, 질소원으로서 1.0% (w/v)의 soytone을 첨가 하여 30oC에서 145 rpm으로 8일간 배양을 최적 생물전환 조건으로 확립하였다. C. allociferrii JNO301에 의해 홍삼 추출물에 존재하는 Rb1, Rb2, Rc, Rf가 생물전환되어 F2, Rh1, Rh2, compound O, compound Mc1, compound K 등 의 minor ginsenosides의 함량이 증가되었다.
발아대두 동충하초의 유산균 발효를 위하여 발아대두와 동충하초가 함유된 배지에서 생육이 우수한 유산균주를 김치로부터 분리하여 동정한 결과 Lactobacillus plantarum KCB001로 명명하였다. 선정된 유산균을 이용하여 발아대두 동충하초의 고상발효조건을 최적화한 결과, 동충하초와 발아대두의 혼합비는 4:1, 가수량은 40%(v/v), 종배양액의 첨가량은 20%(v/w), 최적 발효온도와 시간은 각각 37oC와 72시간으로 확인되었다. 유산균발효에 의해 총 폴리페놀함 량과 DPPH 소거능이 증가하였으며, 특히 동충하초의 지표 물질인 cordycepin 함량은 발효에 의해 24% 증가함으로써 발효에 의해 발아대두 동충하초의 기능성이 증가함을 확인하였다.
Edible biopolymer films were developed from the exopolysaccharides (EPS) extracted from Weissella confusa 113-2. The optimum composition for film formation was determined using the response surface analysis with the explanatory variables of the EPS (0.5-5.5%) and glycerol (0.5-5.5%) concentrations and the response variable of film elastic modulus (EM). The mass ratio of distilled water to solids was set constant (14:1). Tensile strength (TS), percentage elongation at break (%E), EM, water vapor permeability (WVP) of EPS films were evaluated. The glass transition temperatures of the films were also determined by a dynamic mechanical analysis. The optimum mass ratio of EPS to glycerol was 0.754:0.375. The WVP, TS, %E, and EM of the film under the optimal composition were 3.53±0.21 g·mm/kPa·h·m2, 7.03±0.49 MPa, 84.82±12.31%, and 62.03±6.93 MPa, respectively. The glass transition temperature varied from 54 to 83 °C. The EPS film has the potential to be applied to food products as an edible film with physical and barrier properties comparable to other biopolymer edible films.
Acetic acid bacteria strains were isolated from a variety of fermented foods and fallen fruits. Among them, the strain MAK88, whose acetic acid fermentation ability, acid-tolerance, and alcohol-tolerance were high, was selected and identified as Acetobacter orientalis. A seed culture of A. orientalis MAK88 was inoculated into onion juice, and the optimum conditions of acetic acid fermentation was investigated. The optimum initial concentration of ethanol in onion juice was 5% (v/v) and in that condition, acidity was 4.31% at 144 h of fermentation. The optimum initial concentration of acetic acid was 1% and the final acidity was 5.32%. The optimum fermentation temperature was determined to be 28oC. The most appropriate preparation method of onion juice was to heat the onion at 121oC for 15 min and produce juice with pressure followed by filtering, and then sterilization at 121oC for 15 min. Prepared onion juice was used for fermentation without dilution.
Glucansucrase is an enzyme classified as a glycoside hydrolase (GH) 70 family, which catalyzes the synthesis of glucooligosaccharides with a low molecular weight using sucrose as a donor of D-glucopyranose and maltose as a carbohydrate acceptor. In this study, glucansucrase-producing lactic acid bacteria strain was isolated from the fermented foods collected in traditional markets, and the optimum conditions for the oligosaccharide production were investigated. The strain CCK940 isolated from Chinese cabbage kimchi was selected as an oligosaccharide-producing strain due to its high glucansucrase activity, with 918.2 mU/mL, and identified as Leuconostoc lactis. The optimum conditions for the production of oligosaccharides using Leu. lactis CCK940 were to adjust the initial pH to 6.0, add 5% (w/v) sucrose and 10% (w/v) maltose as a donor and acceptor molecules, respectively, and feed 5% (w/v) sucrose at 4 and 8 h of cultivation. When Leu. lactis CCK940 was cultured for 12 h at optimum conditions, at least four oligosaccharides with a polymerization degree of 2-4 were produced.
Glucansucrase is an enzyme classified as a glycoside hydrolase (GH) 70 family, which catalyzes the synthesis of various glucans and glucooligosaccharides with a low molecular weight using sucrose as a donor of D-glucopyranose and maltose as a carbohydrate acceptor. Oligosaccharides are indigestiable carbohydrate with low calories, which have various positive effects on the health of intestinal track. In this study, oligosaccharide produced from Leuconostoc lactis CCK940 was purified and its prebiotics effect was investigated. Leuconostoc lactis CCK940 which isolated from Chinese cabbage kimchi produced oligosaccharide using 5%(w/v) sucrose as a donor and 3%(w/v) maltose as an acceptor. Oligosaccharide produced was purified using Bio-gel P2 column chromatography and DPs of the resulting oligosaccharide were ranged from 3 to 7. When the prebiotics effects of freeze dried oligosaccharide were examined, 1%(w/v) of purified oligosaccharide added to carbohydrate-free MRS showed good prebiotics effects on Lactobacillus plantarum KCCM 12116, L. reuteri KCTC40417, and Bifidobacterium animalis KCCM1209.
For preliminary molecular typing, PCR-based fingerprinting using random amplified polymorphic DNA (RAPD) is the method of choice. In this study, 14 bacterial strains were isolated from different Korean food sources, identified using 16S rRNA gene sequencing, and characterized through RAPD-PCR. Two PCR primers (239 and KAY3) generated a total of 130 RAPD bands, 14 distinct PCR profiles, 10 polymorphic bands, one monomorphic band, and four unique bands. Dendrogram-based analysis with primer 239 showed that all 14 strains could be divided into seven clades out of which clade VII had the maximum of seven. In contrast, dendrogram analysis with the primer KAY3 divided the 14 L. citreum strains into four clades out of which clade IV consisted of a maximum of 10 strains out of 14. This research identified and characterized bacterial populations associated with different Korean foods. The proposed RAPD-PCR method, based on sequence amplification, could easily identify and discriminate the lactic acid bacteria species at the strain-specific level and could be used as a highly reliable genomic fingerprinting tool.
For preliminary molecular typing, PCR-based fingerprinting using random amplified polymorphic DNA (RAPD) is the method of choice. In this study, 14 bacterial strains were isolated from different Korean food sources, identified using 16S rRNA gene sequencing, and characterized through RAPD-PCR. Two PCR primers (239 and KAY3) generated a total of 130 RAPD bands, 14 distinct PCR profiles, 10 polymorphic bands, one monomorphic band, and four unique bands. Dendrogram-based analysis with primer 239 showed that all 14 strains could be divided into seven clades out of which clade VII had the maximum of seven. In contrast, dendrogram analysis with the primer KAY3 divided the 14 L. citreum strains into four clades out of which clade IV consisted of a maximum of 10 strains out of 14. This research identified and characterized bacterial populations associated with different Korean foods. The proposed RAPD-PCR method, based on sequence amplification, could easily identify and discriminate the lactic acid bacteria species at the strain-specific level and could be used as a highly reliable genomic fingerprinting tool.
Fermented food consists of a variety of lactic acid bacteria (LAB) that are also used in the industry as starter cultures. This genus comprises of different species that find importance as a preservatives in food like meat and sausages. Likewise, Lactobacillus brevis has been recognized as GRAS and is a potential probiotic strain extensively being used on an industrial scale. Since such bacteria are directly related to human health, there has been a need to identify and characterize them on the molecular level. In this study, LAB was identified and characterized from various fermented food samples available in South Korea. Two types to PCR-based molecular typing methods were used to analyze the 13 Lactobacillus brevis isolates, of which one was based on difference in the banding patterns originated on agarose gel and the other was related to the sequence analyses of various housekeeping genes in the particular strain. The former rep-PCR technique used three primers namely, REP, ERIC and (GTG)5 that amplified repetitive sequences in the genome and provided characteristic fingerprint profile for each isolate. This clustered the strains in 3 groups with the help of UPGMA method of clustering distinguishing between closely related strains. However, the latter multilocus sequencing typing (MLST) technique provided definite identification of the strains. A set of 7 housekeeping genes were determined as groEL, gyrB, rpoA, rpoB, pheS, recA and dnaK. These genes were amplified and sequenced and were subjected to comparative analysis. Discrete allelic profiles and 13 sequence types (STs) were resolved and minimum spanning tree (MST) was constructed, revealing the genetic relatedness among the isolates. On comparing the results from both the techniques, MLST proved to generate accurate and precise fingerprints owing to the sequence analysis of conserved genes thus providing a scope for research in the monitoring related species.
Glucansucrases are members of GH70 family of glycoside hydrolases and mainly produced by lactic acid bacteria such as Leuconostoc, Lactobacillus, and Weisella species. Glucansucrases use sucrose as a substrate to synthesize glucans as well as to produce oligosaccharides by transferring glucose moiety from sucrose onto acceptor carbohydrate molecules. It is known that some oligosaccharides produced by the reaction of glucansucrase show functional properties such as prebiotics and immunostimulatory activities. In this study, lactic acid bacteria which produce glucansucrase were screened from a variety of fermented foods, vegetables, and fruits collected from various area of Korea. Among 149 lactic acid bacteria strains which were isolated using BCP agar plates, 8 strains were selected which showed high glucansucrase activities. By nucleotide sequence analysis of 16S rRNA gene, strain no. 26-4 and 109-4 were identified as Leuconostoc mesenteroides, strain no. 95-4 strain was L. lactis, strain no. 92-4 and 112-1 were Weissella kimchii, strain no. 94-1 and 95-1 strains were W. confusa, and strain no. 113 was W. cibaria. When the oligosaccharides produced by the reaction of glucansucrase were analyzed using Bio-LC after these lactic acid bacteria were cultured into sucrose-containing media, the chromatograms of all bacterial showed unidentified peaks which implied the newly synthesized oligosaccharides
Recently, many studies have shown that propolis has diverse health beneficial effects such as anti-cancer, anti-bacterial, anti-inflammation, and anti-oxidant activities. Water-insolubility of propolis has made it extremely difficult in manufacturing health beneficial beverages containing propolis. In this study, the solubility of propolis was dramatically improved by entrapping with beta-cyclodextrin and the prebiotics effect of water-soluble propolis on the yogurt fermentation was investigated. Lactobacillus pentosus SC60 was selected as a starter for the yogurt fermentation due to its high DPPH radical scavenging activity. Low-fat milk which was supplemented with different concentrations of propolis (0.01, 0.05, 0.1, or 0.5% (w/v)) was fermented with L. pentosus SC60 for 30 h and the viable cell number, pH, and titratable acidity were checked. The rates of decrease in pH and increase in titratable acidity of yogurt after 12 h of fermentation were the highest when 0.5% (w/v) propolis were supplemented. Meanwhile pH and titratable acidity of yogurt without propolis reached 4.54 and 0.73%, respectively, most slowly after 30 hoffer mentation when compared with other yogurts supple mented with propolis. The viable cell number of L. pentosus SC60 in yogurt with 0.5% (w/v) propolis increased with highest rate and it exceeded 9 log CFU/mL at 8 h of fermentation, but that of yogurt with no propolis was only 8.54 log CFU/mL at 30 h of fermentation. This results showed that L. pentosus SC60 grew very well in the presence of water-soluble propolis and it is proposed that propolis acts as prebiotics
The genus Pediococcus belongs to the lactic acid bacteria and includes 15 species which are used in the food industry as both starter and probiotic cultures. The importance of Pediococcus spp. is due to their use as starter cultures in fermented meat as well as to their presence as the natural microbiota in vegetables. The availability of P. pentosaceus in the food industry increases the need for reliable molecular techniques for strain identification. To date, the reliable molecular methods for definite identification at strain level of microorganisms used in food industry has not been developed. Molecular identification based on suitable marker genes could be a promising alternative to conventional molecular typing methods such as ribotyping. In this study, the applicability of seven housekeeping genes gyrB, pyc, pgm, leuS, glnA, and dalR in combination with the pgi gene in multilocus sequence typing of P. pentosaceus was assessed. Sequencing and comparative analysis of sequence data were performed on 6 strains isolated from various vegetables. In addition to 17 sequence types, two new sequence types were identified and these fortified sequence types and seven marker genes allowed for a clear differentiation of the strains analyzed, indicating their applicability in molecular typing.
Pulsed electronic field(PEF) 처리에 의한 우유 단백질과 물리화학적 특성의 변화를 확인하기 위하여 원유, 탈지유, HTST, LTLT, UHT 우유를 PEF 처리하였다. 시료 중의 단백질을 SDS-PAGE로 확인하였을 때, PEF 처리에 의한 우유 단백질의 변성은 관찰할 수 없었다. Differential scanning calorimetry(DSC)로 우유 단백질의 열변성 정점 온도(Td)를 분석한 결과, 탈지유를 65oC에서 PEF 처리하였을 때 Td가 87.66oC에서 97.18oC로 증가하여 PEF 처리가 우유 단백질의 변성에 영향을 미치는 것을 확인하였다. PEF 처리에 의한 alkaline phosphatase, protease, lactoperoxidase의 잔존효소활성을 측정한 결과, 원유와 탈지유에서 alkalinephosphatase는 PEF 처리에 의해 효소활성이 감소하였다. 또한 protease와 lactoperoxidase의 활성은 PEF 처리에 의해 영향을 받지 않았다. 65oC에서 PEF 처리한 원유는 처리하지 않은 원유보다 높은 갈색도를 나타내었으나, 기타 우유는 PEF에 의한 유의적인 차이가 없었다. 우유를 PEF 처리하였을 경우 산도의 변화는 관찰되지 않았고 pH의 경우에도 PEF 처리 여부에 따라 유의적인 차이는 있었으나 크게 변화하지는 않았다.