국내 액상 발효유용 유산균 스타터 미생물의 동정 및 생리적 특성

전상록,송태석,김지연,신원철,허송욱,윤성식,Jeon, Sang-Rok,Song, Tae-Suk,Kim, Ji-Yoon,Shin, Won-Cheol,Her, Song-Wook,Yoon, Sung-Sik 한국축산식품학회 2007 한국축산식품학회지 Vol.27 No.4

Starters of lactic acid bacteria(LAB) were isolated from the commercial yoghurt products and the four isolates have been studied on their identification and some physiological characteristics. For the purpose of identification, microscopic examination, API test, and 16s rRNA gene sequencing were conducted. Isolate A from a yogurt product of local dairy company A was shown to be Gram-positive rod-shaped bacterium. All strains isolated were turned out to be as Lactobacillus paracasei by using a API 50 CHL kit. In contrast, isolate A was identified as a strain of Lactobacillus helveticus based on the 16S rRNA sequencing data, and L. casei ssp. casei for both B and D and L. paracasei for C. All the isolates survived the simulated gastric juice, pH 2.0 within 3 hours and sharply decreased in viability so that no viable cell was observed after 4.5 hours incubation. In addition, the four isolated strains were almost identical in antibiotic susceptibility to six different kinds of antibiotics including erythromycin ($15\;{\mu}g$), ampicillin ($10\;{\mu}g$), gentamycin ($10\;{\mu}g$), neomycin ($30\;{\mu}g$), but rather resistant to colistin ($10\;{\mu}g$) and streptomycin ($10\;{\mu}g$). It was noteworthy that four isolates were confirmed to produce antibacterial substance against foodborne pathogens of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli 0157:H7 as test organisms based on the inhibitory zones on an MRS soft agar medium. At presence, the inhibitory factor is unknown so that further studies are required to ascertain the active factor responsible for the inhibitory activities.

Tumor Growth Suppression and Enhanced Radioresponse by an Exogenous Epidermal Growth Factor in Mouse Xenograft Models with A431 Cells

임유진,전상록,고재문,우홍균 대한암학회 2015 Cancer Research and Treatment Vol.47 No.4

Purpose The purpose of this study was to evaluate whether an exogenous epidermal growth factor(EGF) could induce anti-tumor and radiosensitizing effects in vivo. Materials and MethodsBALB/c-nu mice that were inoculated with A431 (human squamous cell carcinoma) cellsin the right hind legs were divided into five groups: I (no treatment), II (EGF for 6 days), III(EGF for 20 days), IV (radiotherapy [RT]), and V (RT plus concomitant EGF). EGF was administeredintraperitoneally (5 mg/kg) once a day and the RT dose was 30 Gy in six fractions. Hematoxylin and eosin (H&E) stained sections of tumor, liver, lung, and kidney tissues wereinvestigated. Additionally, tumors were subjected to immunohistochemistry staining withcaspase-3. ResultsEGF for 6 days decreased tumor volume, but it approached the level of the control group atthe end of follow-up (p=0.550). The duration of tumor shrinkage was prolonged in group Vwhile the slope of tumor re-growth phase was steeper in group IV (p=0.034). EGF for 20days decreased tumor volume until the end of the observation period (p < 0.001). Immunohistochemistryrevealed that mice in group V showed stronger intensity than those in groupIV. There were no abnormal histological findings upon H&E staining of the normal organs. ConclusionEGF-induced anti-tumor effect was ascertained in the xenograft mouse models with A431cells. Concomitant use of EGF has the potential role as a radiosensitizer in the design offractionated irradiation.

Identification of Genes Involved in EGF-Induced Apoptosis Using CRISPR/Cas9 Knockout Screening: Implications for Novel Therapeutic Targets in EGFR-Overexpressing Cancers

김재식,이주호,전상록,김용섭,전승혁,우홍균 대한암학회 2023 Cancer Research and Treatment Vol.55 No.3

Purpose Exogenous epidermal growth factor (EGF) causes apoptosis in EGF receptor (EGFR)–overexpressing cell lines. The apoptosis-inducing factors could be a therapeutic target. We aimed to determine the mechanism of EGF-induced apoptosis using a genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)-based knockout screen. Materials and Methods Two-vector system of the human genome-scale CRISPR knockout library v2 was used to target 19,050 genes using 123,411 single guide RNAs (sgRNAs). Recombinant human EGF (100 nM) or distilled water four times was administered to the experimental and control groups, respectively. The read counts of each sgRNA obtained from next-generation sequencing were analyzed using the edgeR algorithm. We used another EGFR-overexpressing cell line (A549) and short hairpin RNAs (shRNAs) targeting five EGF-resistance genes for validation. DUSP1 expression in A431, A549, and HEK293FT cells was calculated using reverse transcription–quantitative polymerase chain reaction. Results We found 77 enriched and 189 depleted genes in the experimental group using the CRISPR-based knockout screen and identified the top five EGF-resistance genes: DDX20, LHFP, REPS1, DUSP1, and KRTAP10-12. Transfecting shRNAs targeting these genes into A549 cells significantly increased the surviving fractions after EGF treatment, compared with those observed in the control shRNA-transfected cells. The expression ratio of DUSP1 (inhibits ERK signaling) increased in A431 and A549 cells after EGF treatment. However, DUSP1 expression remained unchanged in HEK293FT cells after EGF treatment. Conclusion The CRISPR-based knockout screen revealed 266 genes possibly responsible for EGF-induced apoptosis. DUSP1 might be a critical component of EGF-induced apoptosis and a novel target for EGFR-overexpressing cancers.

일본과 한국의 기능성 유제품의 규격기준 및 시장현황에 관한 연구

박다정,이단원,박정민,신진호,김지연,전상록,송태석,윤성식,김진만,Bak, Da-Jeong,Lee, Dan-Won,Park, Jung-Min,Shin, Jin-Ho,Kim, Ji-Youn,Jeon, Sang-Rok,Song, Tae-Suk,Yoon, Sung-Sik,Kim, Jin-Man 한국축산식품학회 2009 한국축산식품학회지 Vol.29 No.4

Changing health awareness has had an important effect on the functional food industry and is creating greater market opportunities. Unfortunately, there is no statement on functional dairy products in the Processing of Livestock Products Act. As a result, there is confusion in the market and legal difficulties with regard to the advertising of functional dairy products. This study was carried out to improve the current standardization of functional dairy products by comparing the domestic Health/Functional Food Act with the Japanese Health Promotion Law, and by investigating scientific data and articles from various literature and the Internet. In Japan, the Ministry of Health, Labor, and Welfare (MHLW) officially presented the Food with Health Claims (FHC) system that consists of Food with Nutrient Function Claims (FNFC), and innovated Food for Specified Health Uses (FOSHU). In 2005, the FOSHU system was changed to include several new subsystems: Current, Standardized, Reduction of disease risk, and Qualified FOSHU. Finally, to manufacture FOSHU, scientific evidence pertaining to such products must be examined by MHLW. Since FNFC was allowed, only 12 vitamins, ${\beta}-carotene$, and five minerals were approved, though without scientific evidence of efficacy. The Korean Health/Functional Food Act requires that health/functional foods (HFFs) be marketed in measured doses. There are two types of HFFs: generic and product-specific. There are 67 ingredients listed in the act for generic HFFs, and if an HFF has a new active ingredient, it is considered a product-specific HFF. Product-specific HFFs must be approved by the Korean Food and Drug Administration (KFDA). With the present standards, it is impossible to label and advertise functional dairy products with health/functional claims. Government agencies must cooperate to solve this problem, and standardization should be carried out by considering existing health/functional products and claims/indications from other countries.

기능성 유제품의 생산 현황 및 관리제도 : 미국,유럽을 중심으로

윤성식 ( Sung Sik Yoon ),송태석 ( Tae Suk Song ),전상록 ( Sang Rok Jeon ),박다정 ( Da Jeong Park ),박정민 ( Jung Min Park ),운재호 ( Jae Ho Woon ),임경종 ( Kyung Jong Lim ),김진만 ( Jin Man Kim ) 한국유가공기술과학회 2008 Journal of Dairy Science and Biotechnology (JMSB) Vol.26 No.2