• Microbiology and Biotechnology Letters
• /
• v.48 no.3
• /
• pp.287-295
• /
• 2020

Lactobacillus zymae GU240 was previously isolated from Kimchi, a Korean fermented vegetable, as a strong GABA producer. The strain showed β-galactosidase (β-Gal) activity on MRS agar plates with X-gal. When growth and β-Gal activities of GU240 were measured using MRS (glucose, 2%, w/v) and MRSL (lactose, 2%, w/v) broths, cells were found to grow slowly in MRSL, and the β-Gal activity (36 units at 4 h) was lower than that of cells grown in MRS (94 units at 16 h). The highest OD₆₀₀ value of the culture in MRS was 1.6 at 24 h at 37℃, whereas that of the culture in MRSL was 0.6 at 16 h. β-Gal activity of the culture in MRS reached the maximum (95.6 u/ml) at 16 h, decreased thereafter, and was not detected at 48 h. β-Gal activity for culture in MRSL reached its highest (36 u/ml) at 4 h and decreased gradually, but some activity (11.05 u/ml) still remained at 72 h. The structural gene encoding β-Gal in L. zymae GU240 was cloned as a 3.1 kb fragment, and DNA sequencing confirmed the presence of complete lacLM genes. lacLM genes from L. zymae GU240 showed 98-99% homologies in nucleotide sequences with other lacLM genes from L. brevis. Reverse transcription (RT)-PCR confirmed the operon structure of lacLM. The results indicated that L. zymae GU240 might be in the process of losing the ability to grow rapidly on lactose-containing medium, such as milk, due to adaptations to plant environments, including kimchi.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.1
• /
• pp.92-100
• /
• 2017

Acetoin (AC) is a volatile platform compound with various potential industrial applications. AC contains two stereoisomeric forms: (3S)-AC and (3R)-AC. Optically pure AC is an important potential intermediate and widely used as a precursor to synthesize novel optically active materials. In this study, chiral (3R)-AC production from meso-2,3-butanediol (meso-2,3-BD) was obtained using recombinant Escherichia coli cells co-expressing meso-2,3-butanediol dehydrogenase (meso-2,3-BDH), NADH oxidase (NOX), and hemoglobin protein (VHB) from Serratia sp. T241, Lactobacillus brevis, and Vitreoscilla, respectively. The new biocatalyst of E. coli/pET-mbdh-nox-vgb was developed and the bioconversion conditions were optimized. Under the optimal conditions, 86.74 g/l of (3R)-AC with the productivity of 3.61 g/l/h and the stereoisomeric purity of 97.89% was achieved from 93.73 g/l meso-2,3-BD using the whole-cell biocatalyst. The yield and productivity were new records for (3R)-AC production. The results exhibit the industrial potential for (3R)-AC production via whole-cell biocatalysis.

• Journal of Life Science
• /
• v.28 no.5
• /
• pp.547-554
• /
• 2018

Flaxseed (Linum usitatissimum L.), also called linseed and one of the raw materials for making linen, is rich in omega-3 fatty acids, vegetable estrogen, ${\alpha}$-linolenic acid, and dietary fiber. Studies on flaxseed have reported various additional effects, such as the inhibition of cholesterol, blood clotting, and tumor growth. In this study, we investigated the functional components of flaxseed fermented with lactic-acid bacteria. Lactic-acid bacteria was inoculated into heat-treated (roasted) flaxseed and fermented at $37^{\circ}C$ for 72 hr. The fermented flaxseed was extracted with 70% ethanol and the antioxidant effect of the fermented extracts according to the lactic-acid bacteria was analyzed. It was confirmed that the total polyphenol contents had expanded by about 1.5-8 times, and the total flavonoid contents had increased around 1.2 times in the case of fermented flaxseed with lactic-acid bacteria compared to non-fermented flaxseed (NFFS). DPPH radical scavenging and superoxide dismutase-like activities had increased around 5.6 and 2.3 times, respectively, in the fermented flaxseed compared to the NFFS at 100 ppm concentration. The study concluded that fermentation of flaxseed with lactic-acid bacteria is possible and that it is effective to increase the antioxidant effects of flaxseed. These results can be applied to the development of improved foods and cosmetic materials.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.6
• /
• pp.787-794
• /
• 2009

In this study, a new method for extending storage-life and palatability of Betula platyphylla sap by applying lactic acid bacteria fermentation was developed. The fluids of saps were filtered through 0.22 ${\mu}m$ membrane filter and each fermented by 8 different lactic acid bacteria which are Lactobacillus acidophilus, Lactobacillus brevis, Leuconostoc mesenteroides, Leuconostoc lactis, Lactococcus lactis, Pediocossus pentosaceus, Pediococcus dextrinicus, Streptococcus thermophilus. All the tested lactic acid bacteria except P. dextrinicus grew fast up to $10^6{\sim}10^7cfu/mL$ levels and lowered pH down to about pH 4 levels in 48 hours in both saps. The produced organic acids and lowered pH level inhibited the growth of spoilage microorganisms almost completely for 2 weeks during storage at room temperature. Addition of xylitol in the saps before fermentation accelerated the growth of lactic acid bacteria and increased the sweetness and overall taste of final product. The filtration process did not affect the mineral compositions of Betula platyphylla saps. Also the compositions and amounts of minerals showed very minor differences before and after fermentation in Betula platyphylla saps inoculated with L. acidophilus. By applying lactic acid fermentation to extend storage-life of tree saps instead of heat treatment, it was possible to keep natural minerals in active forms without any modifications.

• Korean Journal of Organic Agriculture
• /
• v.22 no.3
• /
• pp.491-502
• /
• 2014

The present study was conducted to investigate effective starter culture to improve biological activity of Asarum sieboldii. Antibacterial activity, antioxidant activity and reduction of enteric rumen methane production were used as criterions for biological activity. Ground A. sieboldii was added in MRS broth at 10% (w/v) and fermented by different starter cultures. Weissella confusa NJ28, Weissella cibaria NJ33, Lactobacillus curvatus NJ40, Lactobacillus brevis NJ42, Lactobacillus plantarum NJ45 and Lactobacillus sakei NJ48 were used for starter culture strains. Each starter culture was inoculated with 1% (v/v) ratio and fermentation was performed at $30^{\circ}C$ with agitation (150 rpm) for 48 h. MRS broth for the control was employed without starter culture. Then the fermentation growth was dried and extracted using ethyl alcohol. The growth of starter culture was detected at NJ40, NJ42, NJ45 and NJ48. And the highest cell growth was found in NJ40. Antibacterial activity against to Staphylococcus aureus, Listeria monocytogens, Mannheimia haemolytica and Salmonella gallinarum were observed in the extract fermented by NJ40 and NJ45. All treatments showed antioxidant activities, however, there were no significant differences (p>0.05). In in vitro rumen fermentation, negative control (NC) and positive control (PC) were assigned to without extract and with non-fermented A. sieboldii extract. Significant suppression of gas productions were detected in positive control and treatments compared to negative control (p<0.05). However, total volatile fatty acid production was not suppressed. Significant methane reduction per total volatile fatty acid productions were found in positive control and NJ45 treatment (p<0.05). The present study suggested a fermentation of A. sieboldii using NJ45 strain could improve its biological activity and make possible for its use in bio additive for enteric rumen methane mitigation without suppression of animal productivity.

• Preventive Nutrition and Food Science
• /
• v.3 no.4
• /
• pp.329-333
• /
• 1998

Cell wall (lactic acid bacteria-sonicated precipitate ; LAB-SP) and cytosoll(lactic acid bacteria-sonicated supernatant ; LAB-SS) fractions were prepared from kimchi fermenting lactic acid bacteria such as Leuconostoc mesenteroides, Lactobacillus brevis, Lactobacillus fermentum , Lactobacillus plantarum and Pediococcus acidilactici, with Lactobacillus acidophillus isolated from yogurt. Using the Ames mutagenicity test and SOS chormotest system, the antimutagenic acitivity of those cell fractions was studied . One hundered eighty $\mu$l of LAB-SP from lactic acid bacteria isolated from kimchi, excepting Pediococcus acidilactici, supressed the mutagenicity of 4-nitroquinoline-1-oxide(4-NQO) in Ames mutagenicity test and SOS chromotes system , by above 90% and 60% , respectively. LAB-SP from lactic acid bacteria also inhibited the mutagenicity mediated by 3-amino-1-methyl-5H-pyrido [4,3-b]indole (Trp-P-2). Lactobacillus fermentum, Lactobacillus plantarum, and Lactobacillus acidphillus had higher antimutagenicity against Trp-P-2). Lactobacillus fermentum , Lactobacillus plantarum , and Lactobacillus acidphillus had higher antimutagenicity against Trp-P-2 than the other lactic acid bacteria. However, LAB-SS of lactic acid bacteria did not show any mutagenic activity against 4-NQO in Ames mutagenicity test and SOS chromotest systems. On the mutagenicity of MEIQ and Trp-P-2 , LAB-SS of lactic acid bacteria from kimchi or dairy products exhibited a weaker inhibitory effect than LAB-SP of those bacteria. These results represent that, whether the lactic acid bacteria from kimchi are viable or nonviable, antimutagenic acitivity was still effective. We suggest that the strong, antimutaganic activity of lactic acid bacteria might be found in the cell wall fraction , rather than in the cytosol fraction.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.40 no.3
• /
• pp.131-137
• /
• 2020

The present study investigated effects of antifungal and carboxylesterase inoculant on rumen fermentation with different rumen pH. Corn silage was treated without inoculant (CON) and with a mixed Lactobacillus brevis 5M2 and L. buchneri 6M1 (MIX). Rumen fluid was collected from two cannulated Hanwoo heifers before morning feeding (high rumen pH at 6.70) and 3 h after feeding (low rumen pH at 6.20). Dried corn silage was incubated in the rumen buffer (rumen fluid + anaerobic culture medium at 1:2 ratio) for 48 h at 39℃. Eight replications for each treatment were used along with two blanks. Both in a high and a low rumen pH, MIX silages presented higher (p<0.05) the immediately degradable fraction, the potentially degradable fraction, total degradable fraction, and total volatile fatty acid (VFA) than those of CON silages. Incubated corn silages in a low rumen pH presented lower (p<0.05) total degradable fraction, ammonia-N, total VFA (p=0.061), and other VFA profiles except acetate and propionate, than those in a high rumen pH. The present study concluded that application of antifungal and carboxylesterase inoculant on corn silage could improve degradation kinetics and fermentation indices in the rumen with high and low pH conditions.

• Korean Journal of Acupuncture
• /
• v.29 no.2
• /
• pp.239-249
• /
• 2012

Objectives : This study was investigated to observe Foot Soeum Meridian Muscle in human. Methods : In order to expose components related to Foot Soeum Meridian Muscle, cadaver was dissected in the order of their depth; being respectively divided into superficial, middle, and deep layer. Results : Anatomical components related to Foot Soeum Meridian Muscle in human are composed of muscles such as flexor digitorum brevis tendon, abductor hallucis muscle, psoas major m., erector spinae m., and flexor retinaculum, fascia such as plantar aoneurosis, ligament such as sacrotuberal ligament, sacrospinous lig., nuchal lig., nerves such as plantar cut. br. of med. plantar nerve, med. crural cut. br. of saphenous n., br. of tibial n., post. femoral cut. n., spinal n.(dorsal rami of C4-6, T7-12, L1-3, and S1-3), and autonomic nervous system(sacral plexus, pelvic splanchnic n., etc.), and etc. Conclusions : This study shows comparative differences from established studies on anatomical components related to Foot Soeum Meridian Muscle, and the methodical aspects of analytic process. In addition, Foot Soeum Meridian Muscle in human is a comprehensive concept including the relevant nerves, but it remains questionable.

• Food Science and Preservation
• /
• v.11 no.2
• /
• pp.207-213
• /
• 2004

Methanol extracts were prepared from 32 medicinal herbs of the extracts were tested their microbial inhibition activities against food borne pathogens and/or food poisoning microorganisms, food-related bacteria and yeast. Methanol extracts of Cinnamomum cassia, Paeonia suffruticosa, Alnus japonica, Eugenio caryophyllata and Illicium verum exhibited antimicrobial activity for the microorganisms tested, except lactic acid bacteria and yeast. Minimum inhibitory concentrations(MIC) were about 5 mg/mL for Bacillus subtilis, Staphylococcus epidermidis and Pseudomonas aeruginosa. Cell growth of lactic acid bacteria was inhibitied, but greatly on Leuconostoc mesenteroides. The phenolic compound contents were 10.98 mg/g, 10.31 mg/g, 8.55 mg/g and 6.69 mg/g in Thea sinensis, Eugenia caryophyllata, Alnus japonica and Artenisia capillaris, respectively. Antimicrobial activity appeared to be related to phenol compound content in medicinal herbs. The methanol extracts of medicinal herbs could be suitable for the development of a food preservative.

• Food Science and Biotechnology
• /
• v.14 no.3
• /
• pp.375-379
• /
• 2005

Physicochemical properties, intestinal microbial growth, and inhibitory effects of alcohol-insoluble polysaccharide (AIP) extracted from cucumber peel were investigated. AIP was composed of 14.54% crude protein, 1.04% crude lipid, 13.74 % crude ash, 9.1% soluble dietary fiber, and 41.2% insoluble dietary fiber. AIP showed low bulk density (0.18 g/mL) and water-holding capacity (6.39 g/g), and high oil-holding capacity (3.96 g/g). Pectic substance fractions [water-soluble pectic substance (WSP), ethylenediaminetetraacetic acid-soluble pectic substance (ESP), and alkali-soluble pectic substances (ASP)] and hemicellulose fractions [1 M KOH-soluble hemicellulose (KHP1) and 4 M KOH-soluble hemicellulose (KHP4)] were obtained from sequential chemical fractionation of AIP. WSP showed higher total sugar contents than total uronic acid contents, whereas opposite results were observed in ESP and ASP. Molecular weight distributions of three pectic substance fractions were in order of ASP>ESP>WSP. Ion exchange chromatogram pattern of WSP was different from those of ESP and ASP. Major component of WSP was fraction eluted by 0.05 M ammonium acetate buffer, whereas that of ESP and ASP was fraction eluted by 0.2 M NaOH. WSP and ASP showed growth-promoting activities against Lactobacillus brevis, Bifidobacterium bifidum, and B. longum, whereas B. bifidum and B. longum for ESP. KHP1 and KHP4 fractions had significant growth-promoting activities against B. bifidum.