The diversity and characterization of microorganisms isolated from the soil around several ranches in Korea were confirmed in this study. To isolate halophilic microorganisms, the marine agar medium was basically used and cultivated at 37℃ for several days. After single colony isolation, a total of 116 pure colonies were isolated and phylogenetic analysis was carried out based on the result of 16S rDNA sequencing, indicating that isolated strains were divided into 4 phyla, 23 families, 30 genera and 51 species. To confirm whether isolated strain can be a candidate for the fermentation of diverse food ingredients, amylase, lipase, and protease enzyme assays were performed individually, showing that 92 strains possessed at least one enzyme activity. Especially 4 strains, identified to Jonesia quinghaiensis (isolate name: JSF 19-2), Halomonas alkaliantarctica (isolate name: JSF 21), Bacillus velezensis (isolate name: NWFY-36), and Staphylococcus capitis subsp. urealyticus (isolate name: MSY-5), showed all enzyme activity tested. Moreover, 17 strains showed the ability for auxin production. This result indicated that isolated strains have shown the possibility of the application for the food and feed industries. Therefore, this study has contributed to securing domestic biological resources and the improvement of hydrolytic enzyme activity by using isolated strains.

백합은 항산화, 항균효능 및 만성폐쇄성폐질환에도 효능이 있고, 비수리는 항균, 항산화, 항노화, 피부 미백, 피부 광노화 개선 효과 등의 다양한 약리적 효능이 있다고 보고되고 있다. 본 연구에서는 백합 및 비수리를 열수와 20- 80% 주정으로 추출한 추출물을 대상으로 총 폴리페놀, 총 플라보노이드, 항산화 소거능을 조사하여 백합 추출물과 비수리 추출물의 혼합 비율을 선정하였으며, 혼합한 추출물을 이용하여 음료를 제조한 후 10, 25, 35oC에서 6개월 동안 저장하면서 조사포닌 및 총 플라보노이드 함량 변화 및 이화학적 특성을 조사하였다. 백합·비수리를 함유하는 음료를 각 온도별로 6개월 동안 저장한 후에 pH는 약간 감소하였으며, 산도는 약간 증가하였다. 저장 기간 중 당도와 고형분 함량은 크게 변화하지 않았다. DPPH 라디칼 소거능은 2개월 동안 저장하는 동안에는 초기의 활성과 유의적인 차이를 보이지 않았으나, 온도에 따라 4개월 후와 6개월 후에는 다소 감소하였다. 6개월 동안 저장하는 동안에 명도(L값)와 적색도(a값)는 큰 변화가 없었으나, 황색도(b값) 35oC에서 6개월 저장한 후에 약간 감소하였다. 조사포닌 함량은 저장 2개월까지는 큰 함량의 변화를 나타내지 않았으나, 저장 4개월과 6개월 후에는 감소하는 것으로 나타났다. 총 플라보노이드 함량은 저장 1개월이 지났을 때 저장온도에 상관없이 약 1/2로 감소하였으며, 그 후 6개월까지 일정하게 유지되었다. 백합구근 추출물과 비수리 추출물을 함유한 음료는 6개월 동안 저장하는 동안에 일반세균과 대장균군은 검출되지 않았다.

This study examined the effect of the trust of a restaurant brand on the quality of brand relations centered on the mediating effect of brand promise. The survey was conducted on September 18, 2018 to October 2, 2018, with a total of 707 end users, who are under the age of 19~59, using the restaurant brand for the last six months. The panel survey was conducted by distributing a questionnaire address (URL) email through an online questionnaire. As a result, if you apply the parameters of brand commitment between brand trust and brand relationship quality, brand promise an important role and influence. In particular, only one of the three elements of differentiation, consistency and continue, which are sub-dimensions of brand promise, was continue. This means that consistently long term continue are paramount between brand trust and the quality of brand relationships. These results can be applied to the brand marketing and operations of catering companies.

본 연구는 저온살균(60oC, 5-20분)과 대기압플라즈마(5- 20분)를 병용한 고춧가루 중의 E. coli 저감화 및 시너지 효과를 조사하였다. 저온살균 단일처리시 대장균의 불활 성화는 최대 2 log10 CFU/g(=99% 감소) 이상 나타내었으며, 대기압플라즈마 5, 10, 15, 및 20분간 단일처리 하였을 때 각각 0.4, 0.8, 0.9 및 1.4 log10 CFU/g 감소되었다. 저온 살균 및 대기압플라즈마 단독 처리만으로는 만족할 만한 미생물 저감화효과를 얻을 수 없었기에 저온살균 처리 후, 대기압플라즈마를 병용처리 하여 대장균의 불활성화는 1- 6 log10 CFU/g 이상 감소되었다. 그러나, 저온살균과 대기 압플라즈마 병용처리에 따른 관능적 품질 (색, 이취, 맛, 조 직감 및 전체적인 기호도)에 대한 유의적인 차이는 관찰 되지 않았다(P>0.05). 따라서 고춧가루의 미생물학적 안전성 확보를 위해 저온살균과 대기압플라즈마 단독처리보다 이 둘의 병용처리가 E. coli의 확실한 저감화 효과를 유도 하고 식품 고유의 품질특성을 유지하는데 효과적이었음을 본 연구를 통해 확인되었다.

The purpose of this study was to investigate the antioxidant activity and β-glucan content of extracts extracted by varying the temperature at 30, 55 and 80℃ after hot air drying or freeze drying of Pleurotus ostreatus and Pleurotus eryngii. For the analysis antioxidant activity of each mushroom, β-glucan, total phenol, flavonoid contents, and DPPH․ABTS+․Nitrite assay were measured. Also, the β-glucan content, total flavonoid content and ABTS+ scavenging activity increased with freeze drying rather than hot air drying, and increased with increasing extraction temperature in both mushrooms. However, the total phenol and nitrite scavenging activity increased with hot air drying rather than freeze drying, and decreased with increasing temperature in both mushrooms. DPPH scavenging activity was not significant in both mushrooms, but decreased with increasing extraction temperature. Pearson’s correlations between total flavonoid content and antioxidant activities were r=0.719~0.753 (p<0.01). As a result, the β-glucan content, total flavonoid content, and ABTS radical cation scavenging activity were highest during freeze drying and extraction at 80℃. And the highest total phenol content, DPPH radical scavenging activity and nitrite scavenging activity were obtained during hot air drying and extraction at 30℃.

This research confirmed the diversity and characterization of halophilic microorganisms isolated from the various solar salterns, collected on the inside and outside of the country. To isolate strains, the marine agar medium was basically used and cultivated at 37oC for several days aerobically. After single colony isolation, a totally of 230 pure colonies were isolated and phylogenetic analysis was carried out based on the result of 16S rDNA sequencing, indicating that isolated strains were divided into 4 phyla, 12 families, 27 genera and 64 species. Firmicutes phylum, the main phyletic group, comprised 89.6% with 3 families, 17 genera and 52 species of Bacillaceae, Staphylococcaceae and Carnobacteriaceae. To confirm whether isolated strain can produce industrially useful enzyme or not, amylase, lipase, and protease enzyme assays were performed individually, showing that 177 strains possessed at least one enzyme activity. Especially 17 strains showed all enzyme activity tested. This result indicated that isolated strains have shown the possibility of the industrial application. Therefore, this study has contributed to securing domestic genetic resources and the expansion of scientific knowledge of the halophilic microorganisms community in solar salterns.

본 연구에서는 고추의 수확 및 유통 단계에서 미생물 오염 수준과 그 발생원인을 확인하였고, 이를 바탕으로 수확 단계에 사용된 작업자 장갑의 교체와 온도 관리 및 소형 플라즈마 발생장치를 사용하여 신선 고추에 대한 미생물 오염에 저감화 방안을 모색하고자 하였다. 작업자 장갑 미교체 시 3시간 기준으로 작업 전과 후의 일반세균 미생물 오염증가율이 약 190% 증가하는 것으로 확인되었고, 이에 반해 교체한 작업자의 장갑의 미생물 오염증가율은 15% 증가하는 것으로 나타났다. 유통과정 중 보관 온도는 냉장 보관 보다 상온 보관일 때 미생물 오염 수준이 더 높은 것으로 나타나 냉장 보관이 미생물 오염 예방 에 더 효과적인 것으로 나타났다. 추가로 소형 플라즈마를 이용하였을 때 초기 균 수 대비 5일차에서 일반세균 3.0 log CFU/g 감소, 대장균군, 효모/곰팡이는 불검출로 나타났고 플라즈마 발생장치 없는 경우 5일차에 대장균군이 2.1 log CFU/g 수준으로 검출되어 소형 플라즈마 발생장 치가 보관 및 유통과정 중의 미생물의 저감에 효과적일 것으로 판단되었다. 이상의 결과로 볼 때 수확단계에서 미생물학적 위해요소 발생원인 중 하나인 작업자의 장갑을 주기적으로 교체하고 현장에서 쉽게 수행 가능한 냉장 유통 방법과 신선 고추의 수확 후 보관 및 유통 중에 소형 플라즈마 장치를 이용한다면 고추의 미생물 오염을 감소 시키는데 효과적인 것을 확인할 수 있었다. 또한 고추 이외에도 다른 신선농산물의 수확, 선별 단계나 유통단계에 미생물의 오염을 예방 또는 저감화 하는데 이용이 가능할 것으로 생각된다.

This study was conducted to investigate the antioxidant activities on hydropoic-cultured ginseng roots (HGR) and leaves (HGL). The samples were lyophilized, extracted with 80% ethanol, and then evaluated the antioxidant activities compare with conventional- cultured ginseng. Total polyphenol content of ginseng, HGR, and HGL were 128.85±0.41, 115.74±1.28, and 282.15±5.15 mg/g, respectively. The DPPH radical scavenging activity(IC50) was the highest value of 6.47±0.13 mg/mL in the HGL. The ABTS radical scavenging activity was the highest value of 29.37±0.37 mg AA eq/g in HGL, and ginseng and HGR were 10.23±0.49 and 8.18±0.37 mg AA eq/g, respectively. The reducing power of ginseng, HGR, and HGL were 0.56±0.01, 0.53±0.01, and 0.68±0.01, respectively. Chelating effect was the highest value of 92.65±3.42% in HGL. The results of this study suggest that antioxidant activities in hydropoic-cultured ginseng leaves could have significant health benefits.

In this study, the physicochemical traits of soybean (100-seed weight, seed coat rate, protein content, composition, and amino acid content) and the quality of tofu (texture and sensory characteristics) were evaluated in order to determine the features of six varieties (Saedanbaek, Daechan, Daepung2, Seonpung, Miso, Saegeum) in terms of textural and sensory characteristics of tofu. Regardless of cultivar, the order of amino acid composition rate was as follows: Glutamic acid > Aspartic acid > Arginine > Leucine > Lysine. Approximately 50-60% of tofu (dry weight) consisted of protein, and among the cultivars, Tofu made from Saedanbaek showed the highest amount of protein at 59%. It was followed by tofu made from Miso at 54%. The rest contained about 50% protein. According to the result of correlation, crude lipid (-0.933**), crude protein (0.961**), and total phosphorus (0.924**) were strongly correlated with tofu hardness, and such factors could be utilized as an indicator of tofu quality.

본 연구에서는 V. vulnificus와 V. cholerae를 중심으로 국내에서 유통되는 우렁쉥이에 대한 위해평가를 실시하였다. 위험성 확인 단계에서 병원성 비브리오균의 위험성에 대해 조사하였고, 노출평가 단계에서는 초기오염도를 산출 하기 위하여 네 권역에서 우렁쉥이의 병원성 비브리오균 오염실태를 조사하였다. 또한 대형할인마트, 시장 및 횟집 에서 관리자와의 면담을 통하여 유통 시간을 조사하였으며, 시료의 품온 및 진열대 온도를 직접 측정하여 유통 온도를 수집하였다. 예측모델 개발을 위하여 병원성 비브리오 균을 혼합하여 우렁쉥이에 접종 후 다양한 온도(7oC, 10oC, 15oC, 20oC)에 저장하면서 시간대별로 꺼내어 세균 의 생장 및 사멸을 확인하였다. 섭취자 비율 및 섭취량은 2016년 국민건강영양조사 원시자료를 활용하여 산출하였으며 용량-반응모델 선정을 위하여 문헌조사를 실시하였고, 최종적으로 수집된 데이터들을 활용하여 시나리오를 구성하였다. 오염실태 조사 결과 V. vulnificus는 검출되지 않았으며 V. cholerae는 101개의 시료 중 1개에서 양성으로 검출되었다. 유통환경조사 결과 우렁쉥이는 최소 1시간, 최대 48시간까지 진열되는 것으로 조사되었고 0-10oC 로 유통되는 것을 확인하였다. 예측모델 개발 결과 모든 온도(7oC, 10oC, 15oC, 20oC)에서 병원성 비브리오균은 점차 사멸하는 경향을 띄었으며 개발된 모델의 적합성 검증 결과 RMSE값이 0에 가까워 개발된 모델이 우렁쉥이에서 병원성 비브리오 균의 균주 변화를 묘사하기에 적합하다 고 판단되었다. 섭취자 비율 및 섭취량은 0.26% 및 65.13 g 으로 나타났으며 용량-반응 모델은 Beta-Poisson 모델을 사용하였다. 최종적으로 @RISK Fitting 프로그램을 활용하여 위해도를 추정한 결과, 우렁쉥이를 섭취하였을 경우 1일 1인에게서의 V. vulnificus로 인한 식중독 발생 확률은 평균 2.66×10-15, V. cholerae로 인한 식중독 발생 확률은 평균 1.02×10-12으로 추정되었다. 또한 민감도 분석결과 섭취자 비율이 위해도에 가장 큰 양의 상관관계를 나타내는 것으로 조사되었다. 해당 연구결과는 국내 우렁쉥이 유통 과정에서 병원성 비브리오균에 대한 안전한 수산물을 생산하는데에 기여할 수 있을 것으로 판단된다. 또한 위해 평가 결과는 국내 수산물에서 V. vulnificus와 V. cholerae 에 대한 기준·규격을 설정하는데 기초자료로 활용할 수 있을 것으로 사료된다.

The aim of this study was to investigate the antioxidant activities and quality characteristics of jelly added with 0%, 8%, 16%, 24%, and 32% rhubarb stem juice (RSJ). The moisture content and water activity of jelly samples increased significantly with increasing content of RSJ. The pH was highest in control samples; and the more the amount of RSJ added, the lower. Hunter color value of the jelly showed that L was highest in control samples, but it was not significant in RSJ-added samples. The A value was increased significantly with the addition of RSJ. Hardness, gumminess, and chewiness was highest in samples with 0~8% RSJ, and it decreased by increasing RSJ addition. DPPH radical scavenging activity results showed 60% activity in samples with 32% RSJ. ABTS radical scavenging activity was lowest in control samples and samples with 8~32% RSJ showed 70~80% activity, but it was not significant in samples with 8~32% RSJ. The total polyphenol was increased respectively with increasing levels of RSJ. In terms of consumer acceptance, overall acceptability did not show any significant difference among samples, and the color showed the highest value in samples with 32% RSJ and the lowest value in samples with 8% RSJ.

This research investigated the quality properties of yogurts added to barley (1, 2, and 3%) and tagatose or sucrose. After inoculation of S. thermophilus, pH, titratable acidity (TA), viscosity, and viable cell count were measured at 4 h intervals for 16 h and color value, antioxidant activity, and sensory evaluation were determined after fermentation in triplicate. In the case of yogurt containing only tagatose or sucrose, the pH was hardly decreased, but when 2-3% barley was added, the pH reached below 4.5 before 16 h. In addition, TA and viscosity tended to increase as barely was added. Viable cell count increased slowly in yogurt with tagatose, but rapidly increased when barley was added. As barley content increased, yellowness, redness, and antioxidant activity tended to increase, and significantly higher antioxidant activity in barley tagatose yogurt. Sour strength increased and significant difference in the sweetness was not observed when barley amount increased. Although there was no significant difference in overall acceptability, tagatose yogurt containing 3% barley scored the highest in preference. In conclusion, the fermentation rate of yogurt inhibited by the addition of tagatose is improved by the addition of barley, and the growth rate of lactic acid bacteria is considered to play a role.

본 연구는 원주시 내 대형 초밥 뷔페에서 제공되는 초밥, 회 등 26개 수산물 가공품을 대상으로 DNA 바코드를 분석하여 원재료의 종을 동정하였다. DNA 바코드 증폭을 위하여 미토콘드리아의 16S ribosomal RNA 및 cytochromec oxidase subunit I 유전자 부위를 증폭하는 프라이머 세트를 이용하여 증폭된 PCR 산물의 염기서열을 분석하였다. 확보한 염기서열은 BLAST Search를 이용하여 미국국 립보건원 GenBank에 등록되어있는 생물 종의 염기서열과 비교하여 염기서열 유사도와 매칭 점수를 고려하여 최종 종을 동정하였다. 모니터링 결과 분석 제품의 58%는 제품명과 사용된 원재료가 일치하였지만, 27%에서는 불일치가 관찰되었다. 초메기초밥에는 가이양(Pangasianodon hypophthalmus)이 꽃돔회에는 붉평치(Lampris guttatus)가 사용되었으며, 날치알군함 및 청어알무침에는 열빙어 (Mallotus villosus) 알이 사용되었음을 확인하였다. 타코와 사비군함 및 오징어간장소스에 사용된 원재료는 주꾸미 (Amphioctopus fangsiao) 및 남방주꾸미(Amphioctopus membranaceus)로 각각 동정되었다.

The pine bark extract was added during the beer manufacturing process to develop a functional beer using natural plant materials. Pilsner beer was prepared by adding 0-0.125% to the wort. Immediately before fermentation, extracts were added with yeast cultured twice for 48 hr, and fermentation was carried out at 25°C for 5 d and storage was carried out at 2°C for 15 d. In the experiment, pH, reducing sugars, soluble solid contents, specific gravity, alcohol contents, chromaticity, total flavonoids, total polyphenols, DPPH, and yeast number were tested during fermentation and storage to characterize. The pH, reducing sugar, soluble solid contents, specific gravity, and alcohol contents of the six samples were not significantly different during fermentation and storage. However, yeast number, flavonoids, polyphenols, and DPPH were higher at higher pine bark extract contents. L value in chromaticity was the highest in control, and a value and b value were higher as the amount of extract added. In the sensory test, beer with 0.05% pine bark extract showed the best color, sweetness and aroma. Therefore, it was judged that it is desirable to prepare beer by adding 0.05% pine bark extract to pilsner beer.

In this study, the quality characteristics and antioxidant activities of wet noodles added with doraji (Platycodon grandiflourm) powder at concentrations of 1%, 2%, 3%, and 4%, respectively, were investigated. The crude protein, crude fat, crude ash, crude fiber, and moisture contents of the dried doraji powder were 11.00%, 0.95%, 4.10%, 29.64%, and 6.21%, respectively. As the added amount of doraji powder increased, weight, volume, and water absorption of the wet noodles after cooking decreased. However, the turbidity of the soup increased. Color L values of wet and cooked noodles decreased, while a and b values increased by the addition of doraji powder. Texture measurement indicated that hardness, cohesiveness, springiness, and chewiness of the cooked noodles decreased by addition of doraji powder. The total polyphenol contents and DPPH radical scavenging activity in wet noodles added with doraji powder increased with increasing amounts of doraji powder. Finally, sensory evaluation of wet noodles added with doraji powder revealed that taste significantly decreased. However, flavor, color, texture, appearance, and overall acceptance scores for the 1% addition group ranked significantly higher than those of the other groups. In conclusion, these findings suggest that doraji powder could be used as functional food ingredients.

패류 중 소비량이 높은 굴에서의 고병원성 Vibrio균(V. vulnificus와 V. cholerae)의 식중독 발생 가능성을 분석하기 위하여 위해평가를 실시하였다. 남해권역, 서해권역, 수도권에서 유통되고 있는 굴 88개를 채취하여 V. vulnificus 와 V. cholerae의 오염실태를 조사하고, 생굴에서의 V. vulnificus와 V. cholerae의 생장 경향을 관찰하였다. 2017 년의 국민건강영양조사 데이터를 활용하여 생굴의 섭취자 비율 및 섭취량을 조사하였으며, 생굴 섭취로 인한 V. vulnificus와 V. cholerae의 식중독 발생 가능성을 분석하기 위해 @RISK를 통해 위해평가를 실시하였다. 88개의 생굴에서 V. vulnificus와 V. cholerae는 검출되지 않아 Beta distribution과 자연로그를 이용한 식을 통해 초기오염수준을 추정하였다. 그 결과 두 세균 모두 -3.6 Log CFU/g으로 생굴에 오염되어 있는 것으로 추정되었다. 생굴에 bioaccumulation된 V. vulnificus와 V. cholerae는 생장하지 않고 초기 접종 수준을 유지하는 것으로 확인되었다. 생굴을 섭취했다고 응답한 사람은 7,167명 중 25명이었으며, 따라서 섭취자 비율은 0.35%로 나타났다. 섭취량에 대한 최적확률분포는 exponential distribution으로 나타났으며 생굴의 평균 섭취량은 66.8 g으로 확인되었다. V. vulnificus와 V. cholerae의 용량-반응 모델은 Beta-Poisson model을 사용하였다. 이상의 데이터를 이용하여 위해평가 시뮬레이션을 개발하고 분석하였다. 초기오염수준으로 오염된 생굴을 바로 섭취함으로써 발생할 수 있는 식중독 발생 가능성은 V. vulnificus의 경우 평균 9.08×10-15, V. cholerae는 8.16×10-13이며, 섭취자 비율이 식중독 발생 가능성에 가장 큰 영향을 미치는 것으로 확인되었다.

Effects of heating methods (hot-air heating, roasting, and microwave radiation) and kernel characteristics on the expansion of whole grains from different botanical sources have been examined. Waxy brown rice which composed of hard endosperm with tightly adhering pericarps showed explosive expansion during heating. Scanning electron microscopy showed that starch granules in hard endosperm expanded during heating, forming porous internal structure. Meanwhile those in soft endosperm remained intact since moisture vaporized into the void surrounding the granules. Whole wheat which expanded to the least extent during heating showed the formation of large fissures between pericarp and seed coat, indicating improper rigidity of pericarps as well as endosperm texture for puffing. The degree of expansion and microstructure of kernel varied depending on the heating methods applied due to their different heat transfer characteristics. Hot-air heating resulted in the higher extent of expansion than roasting or microwave radiation. Whole grains heated by either roasting or microwave radiation showed not only similar extent of expansion but also internal microstructures, although roasting process created the formation of an agglomerated mass at the domain of endosperm due to the partial gelatinization of starches.

장과류의 방사능 안전성 확보를 위해 2016년부터 2018년까지 경기도 내 유통 중인 장과류 및 가공식품 15품목 258건을 수거하여 방사능 오염을 분석하였다. 방사능 분석은 게르마늄 감마핵종 분석기를 이용하였으며, 인공 방사성 물질인 요오드(131I)와 세슘(134Cs, 137Cs)을 분석하였다. 모든 제품에서 131I와 134Cs은 MDA (Minimum Detectable Activity)값 이상으로 검출되지 않았고, 39건에서 0.69-808.90 Bq/kg 범위로 137Cs이 검출되었다. 국내산 제품 6건은 0.70- 3.29 Bq/kg 범위에서 검출되었지만, 원재료는 모두 수입산 이었다. 수입산 제품 33건은 0.69-808.90 Bq/kg 방사능 농도를 나타내었으며, 폴란드산 블루베리 분말 제품 1건(808.90 Bq/kg) 및 링곤베리 분말 제품 2건(103.93, 188.46 Bq/kg)은 국내 방사성 세슘의 허용 기준을 초과하였다. 이러한 결과는 식품 안전 확보를 위해 수입산 장과류와 장과류 가공식품에 대한 방사능 검사 강화와 함께 수입 과정에서 더 철저한 관리가 필요한 것으로 판단된다.

In this study, a survey was conducted among university students (119 men and 134 women) in Chungbuk province using questionnaires to investigate the variables and eating patterns related to the use of food delivery apps. A survey was conducted from March 22, 2019 to April 3, 2019. Of the total respondents, 77.2% reported that they had ordered food at least once using food delivery apps on smartphones. Further, 63.3% of the total subjects had ordered food delivery through smartphone apps once or twice a month, and the most preferred cuisine for food delivery was fast food, followed by Bunsik (Korean street food/snack), western food, and Chinese food. The average satisfaction scorefor food delivery apps was 3.8 points, and the satisfaction score was the highest with the convenient ordering process (4.0), followed by good taste (3.9) and good portion (3.8). The subjects who used smartphone food delivery apps three times or more a month showed a significantly higher frequency of instant food intake (p=0.0132), dining out (p=0.0282), and late-night eating (p=0.0047) than the subjects who ordered food using delivery apps less than three times a month. In conclusion, these study results may be applied as baseline data for dietary education among university students.

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.