• Food Science and Industry
• /
• v.44 no.1
• /
• pp.59-62
• /
• 2011

전세계적으로 감염성 질환은 주요한 건강 문제이다. 장내 미생물 균총은 해로운 미생물로부터 숙주를 보호할 뿐 아니라 면역계에 있어서 매우 중요한 역할을 한다. 이점이 바로 프로바이오틱스 즉, 건강에 도움을 주며 살아있는 미생물로 정의되는 기본 개념을 탄생시켰다. Lactobacillus rhamnosus GG(이하 LGG) 균은 세계적으로 가장 많이 연구된 프로바이오틱스 균종 중 하나로서, 확인된 효능의 대부분은 주로 위장관 질환에 관한 것이다. 몇몇 연구를 통해 급성 수양성 설사의 치료, 항생제 관련 증상의 예방, 그리고 여행자 설사에 대한 LGG균의 효과가 밝혀졌다. LGG균은 소아에서 호흡기 감염의 발생을 줄이거나 그 합병증을 감소시키는 것으로 보인다. 많은 연구를 통해 LGG 균, LC705, 그리고 프로피오니박테리움 PJS균을 모두 포함한 복합 유산균 제제인 $LGG^{(R)}$ Extra가 위장관 불편감을 줄이고 삶의 질을 향상시키는 것으로 나타났다. 따라서 LGG균의 사용은 감염성 질병의 관리와 위장관 건강을 얻는데 있어 안전하고 쉬운 방법이라 하겠다.

• Journal of the East Asian Society of Dietary Life
• /
• v.26 no.5
• /
• pp.435-444
• /
• 2016

This study was conducted to investigate the effects of natural preservatives (G3, G3-1, F3, and F3-1) using Cordyceps militaris on improvement of food quality and safety of noodle during storage. Wheat flour noodle were prepared using three different concentrations of natural preservatives (0.100, 0.200, and 0.400%). Changes in microbial populations, pH value, titratable acidity, and sensory evaluation were measured during storage at $12{\pm}2^{\circ}C$ for 3 days. Overall, use of natural preservatives resulted in lower levels of total mesophilic bacteria, coliform, yeast and mold in noodle compared to the control. In particular, natural preservatives using $2{\times}$ MIC concentrations (0.400%) of F3 and F3-1 were effective at maintaining levels of total mesophilic bacteria for noodle during storage. The pH values of noodle made with F3 and F3-1 were higher than the others. The titratable acidity of noodle with natural preservatives did not significantly change during storage. In sensory evaluation, appearance, color, and overall acceptability of noodle with F3 and F3-1 were preferred than the control. These results could provide useful information for developing an alternative preservation method to improve food quality and shelf-life of noodle using natural preservatives.

• Korean Journal of Microbiology
• /
• v.51 no.4
• /
• pp.374-381
• /
• 2015

Occurrences of coastal dredged materials are ever increasing due to port construction, navigational course maintenance and dredging of polluted coastal sediments. Ocean dumping of the coastal dredged materials has become virtually prohibited as London Treaty will be enacted as of the year 2012. It will be necessary to treat and recycle the dredged materials that may carry organic pollutants and heavy metals in a reasonable and effective process: collection of the dredged materials, liquid and solid separation, and treatment of organic compounds and heavy metals. In this study we have developed a continuous bioreactor system that can treat a mixture of silt and particulate organic matter using a microbial consortium (BM-S-1). The steady-state operation conditions were: pH (7.4-7.5), temperature ($16^{\circ}C$), DO (7.5-7.9), and salt concentration (3.4-3.7%). The treatment efficiencies of SCOD, T-N and T-P of the mixture were 95-96%, 92-99%, and 79-97%. The system was also effective in removal of heavy metals such as Zn, Ni, and Cr. Levels of MLSS during three months operation period were 11,000-19,000 mg/L. Interestingly, there was little sludge generated during this period of operation. The augmented microbial consortium seemed to be quite active in the removal of the organic component (30%) present in the dredged material in association with indigenous bacteria. The dominant phyla in the treatment processes were Proteobacteria and Bacteroidetes while dominant genii were Marinobacterium, Flaviramulus, Formosa, Alteromonadaceae_uc, Flavobacteriaceae_uc. These results will contribute to a development of a successful bioremediation technology for various coastal and river sediments with a high content of organic matter, inorganic nutrients and heavy metals, leading to a successful reuse of the polluted dredged sediments.

• Korean Journal of Poultry Science
• /
• v.33 no.2
• /
• pp.141-149
• /
• 2006

An experiment was conducted to investigate the effects of dietary acidifier($Lactacid^(R)$) and essential oil($Immunocin^(R)$) on the performance, nutrient metabolizability, small intestinal microflora, IgG level and leukocytes and erythrocytes in broiler chickens. Five hundred males and 500 females broiler chickens($Ross^(R)$) were divided into 20 pens of 50 chickens(25 birds in each sex). Five pens were assigned to each of four dietary treatments: control, diets containing antibiotics(Bacitracin methylene disalicilate), acidifier($Lactacid^(R)$) and essential oil($Immunocin^(R)$) dietary treatments. Birds were fed experimental diets ad libitum 5 wks. Weight gain, feed intake, and feed conversion rate were significantly affected by dietary treatment(P<0.05). Overall weight gain($0{\sim}5$ wks) of $Lactacid^(R)$ treatment was significantly lower than the others. Feed intake was highest(P<0.05) in the control followed by antibiotics, $Lactacid^(R)\;and\;Immunocin^(R)$ treatment. Feed conversion rate of $Immunocin^(R)$ treatment was lowest(P<0.05) followed by antibiotics, $Lactacid^(R)$ treatment and the control. Production indices of $Immunocin^(R)$ and antibiotics treatments were significantly higher than those of the control and $Lactacid^(R)$ treatment(P<0.05). $Immunocin^(R)$ treatment was the highest and antibiotics was lowest in serum IgG level. The number of leukocytes and stress index(neutrophil/lymphocytes) tended to be lower in $Immunocin^(R)$ treatment than others. There were no significant differences in erythrocytes among the treatments. The cfu of E. coli was significantly lower in $Immunocin^(R)$ and antibiotics treatments than $Lactacid^(R)$ treatment and the control. Metabolizability of crude protein was significantly lower in the control than $Lactacid^(R)\;and\;Immunocin^(R)$ treatment while that of NFE was significantly lower in $Immunocin^(R)\;than\;Lactacid^(R)$ and antibiotics treatments. It was concluded that essential oil product $Immunocin^(R)$ is as effective as antibiotics in improving feed conversion efficiency and production index while $Lactacid^(R)$ is not.

• Journal of Life Science
• /
• v.23 no.1
• /
• pp.79-83
• /
• 2013

A biofertilizer, BIOACTIVE, was manufactured by N-acetyl-thioproline (ATCA) and mineral phosphate solubilizing bacteria. The growth promoting effect of the biofertilizer on lettuce was evaluated under three different pot conditions, and its stability was assessed in the field. According to the results of the pot experiments, plant growth was improved compared with that of control: 128%, 122%, and 153% for the leaf number, leaf length, and leaf mass, respectively. Applying the manufactured biofertilizer increased the concentration of phosphate: 118% and 132% in the cultivation soil and plant cells, respectively. These show that BIOACTIVE may have potential as an effective biofertilizer in agriculture.

• Journal of Animal Science and Technology
• /
• v.53 no.5
• /
• pp.409-418
• /
• 2011

This study was conducted to investigate the effects of dietary probiotics and immunomodulator on growth performance, carcass characteristics, fecal $NH_3$ content and pathogenic bacteria counts in ileum and cecum and ileum of broiler chicken (Korean native chicken, HanHyup No. 3). A total of 120 (day-old) chicks were randomly divided into 5 treatments with 3 replicates and there were 8 birds per replicate. Dietary treatments consisted of five diets; the corn-soybean based control diet (C), the diet containing antibiotics (Avilamycin) 10 ppm (T1), the diet containing probiotics 1 [(Lactobacillus ($4.45{\times}10^6$) + yeast ($1.51{\times}10^6$) + Bacillus subtilis ($3.50{\times}10^5$)] at 0.5% level (T2), probiotics 2 [(Lactobacillus ($6.70{\times}10^7$) + yeast ($3.10{\times}10^6$)] at 0.5% level in diet (T3), and the diet containing probiotics 3 [T2 + ${\beta}$-glucan + organic acid] (T4) and raised for 9 weeks. There were no significant differences among treatments in weight gain, feed intake and feed conversion. Carcass ratios of broilers were higher in T3 and T4 than other treatments, however, the differences were non-significant. Internal organs and liver, heart weight were significantly increased in T4 (p<0.05) compared to other treatments. The fecal $NH_3$ gas content was decreased (p<0.05) in antibiotics fed group than others. However, probiotic fed groups were not different when compared with control. The number of Salmonella and E. coli in cecum were reduced in the group supplemented with probiotics and immunomodulator compared to the antibiotics (p<0.05). In this experiment, we showed that diets containing pro-biotics and immunomodulator were capable of an alternative to antibiotics.

• Korean Journal of Organic Agriculture
• /
• v.27 no.1
• /
• pp.65-76
• /
• 2019

Bacillus genus are found abundantly in various sites and their secondary metabolites were used as potential agents in agriculture, notably plant growth promoting and bio-control. The objective of this study was to develop the culture conditions of GH1-13 strain including higher cell growth, stable endospore-forming and enhancement of potential agents which are related with plant growth promoting and phytopathogen suppression. The optimal carbon and nitrogen sources were determined by glucose and soy bean flour, respectively, then resulted in $7.5{\times}10^9cells/mL$, $6.8{\times}10^9\;endospore\;cells/mL$ and sporulation yield of 90% after 30 h cultivation in 500 L submerged fermenter at $37^{\circ}C$, pH 7.0. Cells and cell-free supernatant of GH1-13 strains showed the potent antifungal activity against phytopathogenic fungi of Colletotrichum gloeosporioides. It was also confirmed that indole-3-acetic acid (IAA) production of GH1-13 strain was greatly increased by addition of 0.3% tryptophan.

• Journal of Life Science
• /
• v.24 no.4
• /
• pp.352-360
• /
• 2014

We evaluated the growth performance, biochemical characteristics, and immune responses in weaning pigs given a diet containing MR-1 (0.2%/feed) or antibiotics (0.1%/feed) for 45 days. In vitro study showed that MR-1 has antibacterial activity against a variety of strains of pathogenic bacteria, especially a strain of cattle-derived Escherichia coli K99 (E. coli K99) by agar diffusion assay. In the in vivo model, 0.2% MR-1-given group clearly ameliorated the weight gain and feed efficiency in the growth performance of weaning pigs compared to the basal diet group (p<0.05). Additionally, 0.2% MR-1 induced an elevation in the levels of mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) and showed a similar pattern ($TNF{\alpha}$ and $IFN{\gamma}$ production) to the antibiotic treated pigs. Taken together, we suggest that 0.2% MR-1 makes probiotics an alternative to antibiotics in weaning pigs.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.7
• /
• pp.1026-1034
• /
• 2016

To develop a natural antimicrobial agent, we investigated the antimicrobial activities of 13 species of edible herbal plant extracts against major Gram-positive foodborne bacteria. Among the 13 screened edible herbal plants, Caesalpinia sappan L. showed the highest antimicrobial activity. In the paper disc agar diffusion assay, Caesalpinia sappan L. extracts had strong antibacterial activities against most Gram-positive bacteria but did not have antibacterial activities against most Gram-negative bacteria. Minimum inhibitory concentrations of the ethanol extract were 0.06 mg/mL against Clostridium difficile and Listeria monocytogenes and 0.03 mg/mL against Staphylococcus aureus. Their inhibitory activities were not reduced by heat treatment or pH adjustment against C. difficile, L. monocytogenes, and S. aureus. Antimicrobial activities were higher in ethanol extract than in distilled water extract. These results support the potential use of Caesalpinia sappan L. ethanol extract as an antimicrobial agent or functional food components against Gram-positive bacteria.

• Microbiology and Biotechnology Letters
• /
• v.49 no.1
• /
• pp.111-119
• /
• 2021

A bacterial strain isolated from a Malva verticillata leaf was identified as Bacillus velezensis MV2 based on the 16S rRNA sequencing results. Complete genome sequencing revealed that B. velezensis MV2 possessed a single 4,191,702-bp contig with 45.57% GC content. Generally, Bacillus spp. are known to produce diverse antimicrobial compounds including bacteriocins, polyketides, and non-ribosomal peptides. Antimicrobial compounds in the B. velezensis MV2 were extracted from culture supernatants using hydrophobic interaction chromatography. The crude extracts showed antimicrobial activity against both gram-positive bacteria and gram-negative bacteria; however, they were more effective against gram-positive bacteria. The extracts also showed antifungal activity against phytopathogenic fungi such as Fusarium fujikuroi and F. graminearum. In time-kill assays, these antimicrobial compounds showed bactericidal activity against Bacillus cereus, used as indicator strain. To predict the type of antimicrobial compounds produced by this strain, we used the antiSMASH algorithm. Forty-seven secondary metabolites were predicted to be synthesized in MV2, and among them, fourteen were identified with a similarity of 80% or more with those previously identified. Based on the antimicrobial properties, the antimicrobial compounds may be nonribosomal peptides or polyketides. These compounds possess the potential to be used as biopesticides in the food and agricultural industry as an alternative to antibiotics.