Lactic acid bacteria as probiotics are intensively used in human and animal species. These probiotic properties of LABs were variable according to bacterial strain and species. However, there was limited information on probiotic properties of monkey origin LABs. In this study, we investigated the antibacterial activity of monkey and human origin LABs against monkey origin enteric bacteria by the agar disc diffusion test and broth culture inhibition assay. All LABs represented enough tolerance to pepsin (0.3%) and bile acid (pH = 2). To 50% of Clostridium perfringens and 20% of Escherichia coli, monkey origin LABs showed statistically higher antibacterial activity compared to human origin LABs (p < 0.05). Also, distinct antibacterial activity was verified among some bacteria species and strains. Higher antibacterial activity against enteric bacteria except for C. perfringens was verified in Lactobacillus johnsonii strains compared to Lactobacillus reuteri and Lactobacillus salivarius. Statistically different antibacterial activity against C. perfringens was verified among strains within L. reuteri and L. johnsonii. In conclusion, we prove the higher probiotic properties of monkey origin LABs against homogenous enteric bacteria although humans and monkeys were phylogenetically similar species. For non-human primates, homogenous LABs should be used as probiotics, not human origin LABs. Furthermore, it was confirmed among monkey origin LABs, L. johnsonii showed a high antibacterial activity on various enteric pathogenic bacteria and was an appropriate lactic acid strain for inhibiting C. perfringens.

The abnormal meat could caused by abscess, fibrosis and granuloma in the region of the neck by the adverse effect of foot-and-mouth disease (FMD) vaccination practice for Korean swine. After FMD vaccination was implemented in 2010, the number of incidences of abnormal meat has been increasing. In this study, it was evaluated whether needless intradermal injection (NII) of FMD vaccine reduces abnormal meat at the injection site in comparison to conventional intramuscular injection (IM). In addition, the onset of humoral immunity was analyzed in order to see if NII of this vaccine is able to mount comparable antibody response with IM. This study was carried out in four Korean pig farms. The O-type FMD vaccine was implemented via NII at three farms and the control group was vaccinated via IM. Antibody titers were compared from the serum samples taken from 10 random pigs at age of 8, 12, 16 and 22~24 weeks of age. The O+A type FMD vaccine was also compared with the same protocol. When test animals were slaughtered, incidence, type and size of abnormal meat were recorded. The results of this study showed that the antibody titers between intradermal and intramuscular group were similar but a significant difference in the incidence of abnormal meat formation was observed between two groups (p < 0.05). In summary, needless intradermal injection of FMD vaccination was proven to be effective for the onset of humoral immunity and reducing abnormal meat formation.

The purpose of this study was to investigate probiotic characteristics and immune enhancing effects of Bifidobacterium (B.) longum KBB1-26 and BIF-4, B. breve KBB5-22 isolated from human intestine for probiotic use in humans and animals. We measured acid, bile and heat tolerance, antimicrobial activity against pathogenic bacteria, Escherichia (E.) coli, Salmonella (S.) Enteritidis, Staphylococcus (S.) aureus, and Listeria (L.) monocytogenes. Immune enhancing effects of B. longum and B. breve were investigated by measuring nitric oxide (NO), nuclear factor (NF–κb), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-12 (IL-12) and tumor necrosis factor- α (TNF- α) in RAW 264.7 cells or RAW BLUE cells. B. longum KBB1-26 was survived at pH 2.0. B. longum KBB1-26 and BIF-4, B. breve KBB5-22 also showed tolerance to 0.3% of oxgall bile salt. B. longum KBB1-26 was able to survive at 70 ℃ and 80 ℃ for 20 min. KBB1-26 showed the antimicrobial inhibition zone to pathogenic bacteria such as E. coli (12 mm), S. Enteritidis (14 mm), S. aureus (14 mm) and L. monocytogenes (41 mm). The production of NO (4.5 ± 0.00μM/mL) and IL-1β (39.7 ± 0.55pg/mL) of KBB1-26 significantly higher than BIF-4 and KBB5-22, respectively. In addition, KBB1-26 and KBB5-22 induce the production of high level of TNF-α and IL-6 in macrophages. Collectively, B. longum KBB1-26 have acid, bile, heat tolerance, antimicrobial activity and immune enhancing effects. These results suggest that KBB1-26 can be used as probiotics for humans and animals.

It has been known that the ability of Shiga toxinproducing Escherichia coli (STEC) to produce Stx2e in culture media plays a role in the diagnosis of edema disease and determination of subunit vaccine candidates in STEC isolates. To examine the efficiency of Stx2e production in several commercial media, a Stx2e-producing strain (KEFS1302) was grown in four different media: ISO-Sensitest broth (ISB), E. coli broth (ECB), trypticase soy broth (TSB), and Mueller Hinton broth (MHB), with or without mitomycin C at 37°C (250 rpm) for 6 h. Toxin production was measured by enzyme-linked immunosorbent assay. In the presence of mitomycin C, ECB was found to be the most suitable medium, reaching a production peak (OD600 = 1.2) at 1 h; Stx2e was mostly produced during the logarithmic phase (within 3 h). On the other hand, toxin production in ISB reached a peak at 3 h after incubation in the absence of mitomycin C. Stx2e was purified by fast protein liquid chromatography (FPLC) using anion-exchange chromatography. The 43 kDa band of Stx2e was confirmed by western blot using the ECB supernatant. Our results showed that ECB and ISB media would be a suitable medium for mass production of Stx2e even if the toxin production is dependent on time.

The emergence of antimicrobial resistant Escherichia (E.) coli is a major problem in pig farms. To tackle this issue, in July 2011, the Korean government banned the use of antimicrobials for growth promotion of animals in farms. Moreover, E. coli encoding the Stx2e gene cause edema disease which results in high mortality and morbidity in pig farms. Therefore, the aim of this study was to investigate the prevalence of antimicrobial resistance among E. coli encoding the Stx2e gene isolated from weaned piglets with diarrhea before and after the ban on antibiotic growth promoters (AGPs) in Korea from 2007 to 2016. In this period, 479 E. coli isolates were obtained from weaned piglets with diarrhea, and of them, 144 E. coli isolates encoding the Stx2e gene were detected by polymerase chain reaction. The susceptibility of the E. coli isolates to antibiotics were tested using the standard Kirby-Bauer disk diffusion method. The most frequently observed resistances in isolates obtained from weaned piglets in the last 10 years were to tetracycline (92.4%) and chloramphenicol (88.9%). The prevalence of resistance to colistin (3.1% to 16.5%) and tetracycline (86.2% to 97.5%) was also observed to have increased over this period. Additionally, multi-drug resistance was also found to have increased (87.7% to 97.5%) after the ban on AGPs. These findings provide useful data for designing prevention and treatment strategies for postweaning diarrhea and edema disease, and can be used in future studies on antimicrobial resistance in Korea.

Aging is a growing concern of age-associated aberrations in immune system or immunosenescence. Probiotics contain not only these general health advantages but also other the regulation of host immune function. Among those probiotics, the immunomodulatory effects of Weissella cibaria JW15 (JW15) strain has already been reported in our previous studies. The objective of this study is to assess improved immunity of JW15 strain in aged mice. In experiment, mice were divided into five groups. Twenty eight–month-old C57BL/6J mice were given a daily dose of 1×109 CFU/ mouse (JW15-H group) and 1×108 CFU/mouse (JW15- L group) of viable JW15. The young mice group (YM) and old mice group (OM) were given PBS. After four weeks of administration, mice were euthanized. Mice blood was collected and analyzed for complete blood cell count (CBC). Then, mice spleen was weighed and analyzed for splenocyte. Finally, we measured the concentration of cytokine secreted by splenocyte and serum. The results showed splenocyte proliferation of JW15-L group by the addition of LPS and concanavalin A was significantly higher than that of OM group. Splenocyte TNF-α production was significantly increased by JW15 intake. In particular, splenocyte TNF-α production of JW15-L group by the addition of LPS (5 μg/mL) was significantly greater than that other group. Splenocyte IL-6 production was also the highest in JW15-L group. Serum IFN-γ production of JW15-L (59.13 ± 16.13 pg/mL) group was significantly higher than that of OM group (39.71 ± 2.51 pg/ mL). When compared to the OM group (32.22 ± 1.92 pg/mL), Serum TNF-α production was significantly increased by JW15-H intake (69.01± 26.51 pg/mL). In conclusion, JW15 enhanced immunomodulative effects. In particular, the effect was significantly excellent in JW15-L group (1 × 108 CFU/mouse). Therefore, Weissella cibaria JW15 would be suitable for consideration as a helpful functional food for companion animals and humans.

Characteristics and immuno-modulatory effects of Enterococcus (E.) faecium JS1-8 isolated from Kimchi were investigated for potential probiotic use. We measured their acid, bile, and heat tolerances, adhesion properties in Caco-2 cells, antimicrobial activity against pathogenic bacteria, and bacteriocin-like substance-producing activity. Immuno-modulatory effects of E. faecium JS1-8 were measured by determination of nitric oxide (NO), nuclear factor-κB (NF-κB), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) production in RAW 264.7 cells or RAW BLUE cells. JS1-8 survived at pH 2.0 for 2 hr and showed tolerance to 0.3% oxgall bile salt, and it survived after exposure for 5 min at 80°C. JS1-8 showed high antimicrobial inhibition zones to Staphylococcus aureus (460 mm), Listeria monocytogenes (310 mm), Salmonella enteritidis (280 mm), and E. coli (150 mm). Bacteriocin-like substance produced by JS1-8 showed a broad spectrum of activity against Listeria monocytogenes KCCM 40307 and Lactobacillus sake KCCM 40264. Low concentration (1 × 107 CFU/mL) of heat-killed E. faecium JS1-8 induced statistically higher production of NO than Lactobacillus rhamnosus GG (LGG), which is a well-known immuno-modulatory lactic acid bacteria. Low and high (5 × 107 CFU/mL) concentrations of JS1-8 induced statistically higher production of NF-κB than that produced by LGG. We also found that JS1-8 increased production of pro-inflammatory cytokines such as IL-1β and TNF-α in a concentration-dependent manner. As a result, E. faecium JSI-8 could be used as a useful probiotic for controlling pathogens and enhancing host immune responses.

In this study, characteristics and immuno-modulatory effects of Weissella cibaria JW15 isolated from Kimchi, traditional Korean fermented food, were examined for investigation of the capacity of potentially probiotic strains. We measured acid, bile, and heat tolerance, adhesive properties to intestinal epithelial cells, and inhibitory activity against pathogens. JW15 could survive at pH 3.0 for 2 hr, but not at pH 2.0. JW15 also showed tolerance to 0.3% oxgall bile salt, and heat tolerance at 70°C and 80°C for 5 min, respectively. Adhesive ability to Caco-2 cells was similar to that of Lactobacillus rhamnosus GG (LGG), a well-known commercial probiotic. JW15 exhibited antimicrobial activities to pathogenic bacteria such as Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Salmonella enteritidis. The immuno-modulatory effects of JW15 were compared with those of LGG, a well-known immune enhancer. For analysis, production of nitric oxide (NO), NF-κB (Nuclear factor κB), Interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) was measured. The concentration of NO induced by JW15 was higher than that by LGG at low concentration (1 × 107 cfu/mL). Low and high (5 × 107 CFU/mL) concentration of JW15 induced statistically higher production of NF-κB, IL-1β, and TNF-α than that produced by LGG, respectively. In conclusion, Weissella cibaria JW15 had ability as a probiotic strain, including acid, bile, and heat tolerance, adhesive properties to intestinal epithelial cells, and inhibitory activity against pathogens. In addition, JW15 showed better immuno-modulatory effects than LGG when NO, NF-κB, IL-1β, and TNF-α were measured. According to these results, the characteristics and immunomodulating activity of Weissella cibaria JW15 are suitable for consideration as a potential probiotic.

The aim of this study was to evaluate immunopotentiating activities of β-glucan derived from Saccharomyces (S.) cerevisiae and to select new strains having possibility as an immune-enhancing substance. We examined SB20 strains derived from commercial product as a control, and extracted β-glucans from the four strains of S. cerevisiae. RAW264.7 macrophages were treated with heat-killed yeasts, β-glucans, and lipopolysaccharide (LPS). The production of nitric oxide (NO) and cytokines such as TNF-α and IL-1β were then quantified. When macrophages were induced directly by in vitro addition of β-glucan, little production of NO and IL-1β was observed. When pretreated with strong stimulants, i.e., LPS, most yeasts showed down-modulation of NO and IL-1β production. However, TNF-α secretion was triggered by β-glucans and even more increased by the mixture effect of LPS and β-glucans. In particular, S6 strain induced TNF-α secretion more than other strains. Therefore, we can conclude that the S6 strain has possibility as an immune-enhancing substance.

Lactic acid bacteria (LAB) are known to promote activation of macrophages, selectively eliminate harmful intestinal bacteria that enter the body, and increase secretion of cytokines, chemokines, and inflammatory mediators that boost the immune system. In the current study, the immune-enhancing effects of five Leuconostoc stains (Leu. kimchii WK18, Leu. citreum DH33, Leu. mesenteroides DH34, SE34, and GY17) isolated from traditional Korean fermented food, Kimchi, were evaluated. Lactobacillus rhamnosus GG (LGG), which is known for its extraordinary immunopotentiating activity, was used as a reference strain. According to the results, several heat-killed Leuconostoc strains induced a higher level of NO, IL-1β, or TNF-α production than the LGG strain. Collectively, results of the current study suggest that Leuconostoc strains could enhance immune response through activation of macrophages, and could be significant references when verifying the possibility for use of Leuconostoc strains as probiotics, starter, dietary supplement, or immune-enhancing medicine.

This study was carried out to evaluate the genotoxicity of the gamma-irradiated (0, 5 and 10 kGy) milk and ice cream. The Salmonella typhimurium reversion assay was performed using S. typhimurium TA98, TA100, TA102, TA1535 and TA1537 as tester strains. The number of revertant colonies were not increased in both milk and ice cream, compared with negative controls with or without metabolic activation. There were no significant differences among the irradiation doses. These results indicate that the gamma-irradiated milk and ice cream do not show any genotoxic effect under these experimental conditions, and that they may be safe genotoxically.

본 연구에서 사용한 홍삼 전분은 홍삼 농축액 제조 공정에서 발생하는 부산물중 하나로 현재까지는 특별한 활용도가 없었다. 하지만 홍삼 농축액 제조 과정에서 발생되는 홍삼 유래의 물질로 홍삼의 유효 성분인 진세노사이드 및 각종 유리당, 탄수화물 등이 풍부한 안전한 소재로서의 가능성을 알아보고자 하였다. 홍삼전분을 이용한 새로운 홍삼막걸리의 차별화를 위하여 제품의 진세노사이드 함량, 유기산, 유리당, 효모수 등을 분석하였다. 효모 생균수의 변화 조사결과 4℃에서 저장하였을 때는 저장 20일까지 효모 균수에 큰 변화가 없었지만 25℃ 저장에서는 저장 20일에 초기 효모균수의 약 75%가 감소되었다. 유기산분석 결과 막걸리에서는 lactic acid가 4.16 mg/mL의 농도로 가장 많았으며, 그 다음으로는 citric acid 0.88 mg/mL, malic acid 0.39 mg/mL의 순서로 많았다. 저장 초기에는 malic acid의 함량이 4℃ 및 25℃에서 0.39 mg/mL 와 0.58 mg/mL 이었으나 저장일이 20일 경과하였을 때에는 0.46 mg/mL 그리고 0.17 mg/mL으로 측정되었고 대부분의 유기산은 저장기간에 관계없이 변화가 크게 나타나지 않았으나 butyric acid는 증가를 보였다. 20일 경에 lactic acid와 isobutyric acid는 감소하였으며 다른 종류의 유기산은 증가를 보였다. 유리당 분석결과 glucose가 4.4 mg/mL, sucrose 2.8 mg/mL 그리고 mannose 1.4 mg/mL 으로 막걸리의 주 구성당으로 분석되었으며 저장기간이 지속되면서 sucrose, glucose, mannose의 함량은 감소를 보여 알콜 발효의 주요 기질로 사용되었음을 보여주었다. 저장 4~8일 이후부터는 당이 급격히 감소하였으며 8일 이후부터는 큰 차이를 보이지 않았다. 이것은 저장 중 당분이 알콜과 탄산가스로 분해되었기 때문에 함량이 감소한 보여진다. 4℃에서 저장시, 일반적인 유통기간보다(10일) 긴 20일 동안 유리당의 변화를 보였으며 유리당은 12일 경에 sucrose, glucose와 mannose의 양은 1/2으로 감소하였다. 총산 및 pH 분석결과 각 저장온도에서 저장기간에 따른 pH의 변화는, 4℃에서 저장한 경우, 저장 4일경 pH 4.3에서 8일경 pH 3.8로 떨어지면서 저장기간 동안 서서히 감소되었다. 25℃에서 저장한 경우, pH 4.6~3.2 수준으로 4℃ 저장 온도보다 25℃ 온도에서 pH가 낮게 관찰 되었고 진세노사이드 분석결과 함량은 2.47 mg/g으로 측정되었다.