• Journal of Microbiology and Biotechnology
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• 제25권2호
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• pp.178-184
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• 2015

This work aims to utilize wastes from the potato starch industry to produce single-cell protein (SCP) with high lysine content as animal feed. In this work, S-(2-aminoethyl)-_L-cysteine hydrochloride-resistant Bacillus pumilus E1 was used to produce SCP with high lysine content, whereas Aspergillus niger was used to degrade cellulose biomass and Candida utilis was used to improve the smell and palatability of the feed. An orthogonal design was used to optimize the process of fermentation for maximal lysine content. The optimum fermentation conditions were as follows: temperature of 40℃, substrate concentration of 3%, and natural pH of about 7.0. For unsterilized potato starch wastes, the microbial communities in the fermentation process were determined by terminal restriction fragment length polymorphism analysis of bacterial 16S rRNA genes. Results showed that the dominant population was Bacillus sp. The protein quality as well as the amino acid profile of the final product was found to be significantly higher compared with the untreated waste product at day 0. Additionally, acute toxicity test showed that the SCP product was non-toxic, indicating that it can be used for commercial processing.

• 한국축산식품학회지
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• 제40권3호
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• pp.362-376
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• 2020

Rabbit meat bekasam is a traditional fermentation product from Indonesia. This study aimed to determine the chemical and microbiological characteristics of rabbit meat bekasam during the fermentation process in order to isolate, characterize (in vitro and in vivo), and identify lactic acid bacteria (LAB) as the probiotic candidate. The chemical contents of bekasam on 7-day fermentation were investigated in explorative and experimental methods in a completely randomized design. A proximate analysis reported a decrease in the moisture content, fat and carbohydrate content, and an increase in protein content. Also, lactic acid content was increased from 0.48% to 1.12%, and pH was decreased from 5.3 to 4.3. Other properties indicated different values, such as bacteria (2.75×10⁶ to 4.45×10⁷ CFU/g), total LAB (3.82×10⁶ to 4.67×10⁸ CFU/g), total yeast (9.89×10⁶ to 3.82×10⁸ CFU/g) and total mould (4.34×10¹ to 4.86×10³ CFU/g). The experiment produced nine LAB isolates, including two probiotics subjected to further 16S rRNA gene analysis, which indicated that Lactobacillus buchneri was the potential probiotic isolate. After being tested on BALB/c mice, L. buchneri could improve the immune system by inhibiting the growth of Coliform and Salmonella.

• 한국조리학회지
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• 제21권6호
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• pp.195-205
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• 2015

본 연구는 고추씨 분말을 부재료로 이용하여 0%, 10%, 20%, 30% 별로 첨가량을 달리한 고추씨 고추장을 제조하여 $28^{\circ}C$에서 100일 동안 숙성시키면서 화학적 특성을 조사하였다. 총 균수는 발효 기간 중 2.7~3.22 log CFU/g 의 수준을 유지하였으며. 처리구간에 차이는 없었고, 산도의 변화는 pH와 반대로 숙성기간 동안 증가하는 경향을 보여 숙성 100일째 고추씨분말 첨가 고추장의 산도는 0.45~0.42 mg% 수준이었다. DPPH 라디칼 소거 활성은 제조 초기보다 고추씨첨가량이 많을수록 숙성 될수록 증가하였다. 기호성 등의 관능검사에서 고추씨가루(20% 첨가)에서 가장 발효에 적합한 조건으로 판단된다.

• 한국식품위생안전성학회지
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• 제23권2호
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• pp.91-97
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• 2008

Kimchi is a representative traditional food in Korea and a type of vegetable product that is the unique complex lactic acid fermentation in the world. It can be considered as a unique fermented food generated by various flavors, which are not included in raw materials, that can be generated by mixing and fermenting various spices and seasonings, such as red pepper powder, garlic, ginger, and salted fish, added to Chinese cabbages. Functionalities in Kimchi have been approved through several studies and the probiotic function that is mainly based on lactic acid bacteria including their physical functions in its contents has also verified. Studies on the verification of the safety of Kimchi including its physiological functions have been conducted. In particular, the function of lactic acid bacteria, which is a caused of the fermentation of Kimchi. Although the lactic acid bacteria contributed to the fermentation of Kimchi is generated from raw and sub-materials, the lactic acid bacteria attached on Chinese cabbages has a major role in the process in which the fermentation temperature and dominant bacteria are also related to the process. The salt used in a salt pickling process inhibits the growth of the putrefactive and food poisoning bacteria included in the fermentation process of Kimchi and of other bacteria except for such lactic acid bacteria due to the lactic acid and several antimicrobial substances generated in the fermentation process, such as bacteriocin and hydrogen peroxide. In addition, the carbon dioxide gas caused by heterolactic acid bacteria contributes to the inhibition of aerobic bacteria. Furthermore, special ingredients included in sub-materials, such as garlic, ginger, and red pepper powder, contribute to the inhibition of putrefactive and food poisoning bacteria. The induction of the change in the intestinal bacteria as taking Kimchi have already verified. In conclusion, Kimchi has been approved as a safety food due to the fact that the inhibition of food poisoning bacteria occurs in the fermentation process of Kimchi and the extinction of such bacteria.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.422-427
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• 2003

Rhodopseudomonas palustris P4 can produce $H_2$ either from CO by water-gas shift reaction or from various sugars by anaerobic fermentation. Fermentative $H_2$ production by P4 is fast, but its yield is relatively low due to the formation of various organic acids. In order to increase $H_2$ production yield from glucose, P4 was investigated for the photo-fermentation of acetate which is a major by-product of fermentative $H_2$ production. Experiments were performed in batch modes using both light-grown and dark-grown cells. When the dark-grown P4 was challenged with light and acetate, $H_2$ was produced with the consumption of acetate after a lag period of 25 h. $H_2$ production was inhibited when a nitrogen source, especially ammonium, is present. When the dark-fermentation broth containing acetate was adopted for photo-fermentation with light-grown cells, $H_2$ production and concomitant acetate consumption occurred without a lag period. The $H_2$ yield was estimated as 2.4 - 2.8 mol $H_2/mol$ acetate and the specific $H_2$ production rate was as 9.8 ml $H_2/g$ cell${\cdot}$h, The fact that a single strain can perform both dark- and light-fermentation gives a great advantage in process development Compared to a one-step dark-fermentation, the combined dark- and light-fermentation can increase the $H_2$ production yield on glucose by two-fold.

• 한국식품영양과학회지
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• 제32권5호
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• pp.679-683
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• 2003

저장성이 낮은 딸기의 효율적인 이용 및 고부가가치 가공제품 개발을 위해 딸기식초 발효의 1단계인 딸기 과즙의 알콜 발효조건을 모니터링하였다. 딸기를 이용한 알콜발효에서 알콜함량이 가장 높게 나타나는 조건은 초기당도가 16.32$^{\circ}$Brix, 발효시간이 53.03 hr 및 발효온도가 28.83$^{\circ}C$일 때 가장 높은 9.22%를 나타내었으며, 산도가 가장 낮게 나타난 조건은 초기당도가 13.18$^{\circ}$Brix, 발효시간이 50.99 hr 및 발효온도가 24.69$^{\circ}C$일 때 가장 낮은 0.49%를 나타내었으며, 잔당함량이 가장 낮게 나타난 조건은 초기당도가 15.00$^{\circ}$Brix, 발효시간이 52.00 hr 및 발효온도가 26.0$0^{\circ}C$일 때 가장 높은 3.97$^{\circ}$Brix를 나타내었다. 알콜 발효조건에 따른 품질검사 결과 딸기식초 발효용 딸기 wine제조를 위한 최적 알콜 발효조건은 초기당도가 14$^{\circ}$Brix, 발효온도가 28$^{\circ}C$ 및 발효시간이 50 hr 일 때였다.

• Applied Biological Chemistry
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• 제44권2호
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• pp.81-87
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• 2001

굴을 대상으로 조미 양념 젓갈(salt-fermented oyster)과 전통적인 게장의 제조법을 이용한 젓갈 제품(oyster in soy sauce)으로 새로운 형태의 젓갈을 제조하여 각각 진공 및 무진공 상태로 저장하면서 숙성 형태별 숙성 기간에 따른 이화학적 성분의 변화를 살펴 보았다. 굴 젓갈에 있어서 pH는 숙성 기간이 경과함에 따라 점차 감소했으나, 아미노태 질소(AN)와 휘발성 염기 질소(VBN)는 반대로 증가하는 경향을 나타냈으며, 함량에 있어서는 AN의 경우 진공 숙성시에, VBN은 무진공 숙성시에 더 많은 것으로 나타났다. 총균수는 어느 정도 증가했다가 감소하는 경향은 비슷하나 진공 숙성에 비해 무진공 숙성시에 더 현저하였다. 총 구성 아미노산에 있어서는 숙성이 진행됨에 따라 진공의 경우 함량이 증가했거나 감소한 경우라도 무진공 숙성시에 비해 함량이 높은 것으로 나타났다. 이상의 결과를 종합해 볼 때,무진공 숙성시보다 진공 숙성시 숙성이 지연되는 것으로 보여지며, 숙성 지연으로 인한 젓갈의 품질 유지 기간의 연장에도 진공 숙성이 효과적이라고 사료되었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.272-276
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• 2005

Candida tropicalis, an osmophilic strain isolated from honeycomb, produced xylitol at a maximal volumetric production rate of 3.5 g $l^{-1}$ $h^{-1}$ from an initial xylose concentration of 200 g $l^{-1}$. Even with a very high xylose concentration, e.g., 350 g $l^{-1}$, this strain produced xylitol at a moderate rate of 2.07 g $l^{-1}$ $h^{-1}$. In a fed-batch fermentation of xylose and glucose, 260 g $l^{-1}$ of xylose was added, and xylitol production was 234 g $l^{-1}$ for 48 h, corresponding to a rate of 4.88 g $l^{-1}$ $h^{-1}$. To increase the xylitol production rate, cells were recycled in a submerged membrane bioreactor with suction pressure and air sparging. In cell-recycle fermentation, the average concentration of xylitol produced per recycle round, total fermentation time, volumetric production rate, and product yield for ten rounds were 180 g $l^{-1}$, 195 h, 8.5 g $l^{-1}$ $h^{-1}$, and 85%, respectively. When cell-recycle fermentation was started with the cell mass contratrated two-fold after batch fermentation and was performed for ten recycle rounds, we achieved a very high production rate of 12 g $l^{-1}$ $h^{-1}$. The production rate and total amount of xylitol produced in cell-recycle fermentation were 3.4 and 11 times higher than in batch fermentation, respectively.

• 한국식품조리과학회지
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• 제16권6호
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• pp.557-567
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• 2000

An optional ingredient, jasoja(Perillae semen), was adopted to improve the quality of Dongchimi. The final weight percentage of jasoja in Dongchimi was adjusted to 0, 0.25, 0.5, 0.75, or 1.0%, per radish, and sensory and microbiological characteristics were determined during fermentation at 10 for 45 days. The effect was varied depending on the amounts of jasoja, but Dongchimi fermented with 0.5% jasoja was most favored for color, flavor, taste, texture, and overall acceptability in sensory evaluation. According to a quantitative descriptive analysis for the product, the liquid portion of Dongchimi steadily became clearer and less sour in proportion to the amount of added jasoja. However, a strong off-taste was detected from 1.0% treatment. The viable cell numbers of total and lactic acid bacteria drastically increased during the first 2 days, and then gradually increased to their maximum values during fermentation and slowly decreased at the later stage. Dongchimi with 0.5% treatment showed a distinctive high number of microorganisms at the 15th-day of fermentation and this trend was maintained until the completion of fermentation. The lactic acid bacteria isolated and identified from Dongchimi were; Lactobacillus brevis, Lactobacillus plantarum, Leuconostoc mesenteroides, Lactococcus faecalis, and Lactococcus lactis. The combined number of Lactobacillus brevis and Lactobacillus plantarum began to increase right after preparation to as much as 10$\^$7/CFU/㎖, then decreased to 10-10$^3$CFU/㎖ afterward. This study showed that the addition of jasoja retarded the initial fermentation of Dongchimi; however, too much jasoja at above 1% weight level per Chinese radish might accelerate fermentation at the later fermentation stage and shoud be avoided. A comparable fermentation pattern was observed among the samples; however, more acceptable Dongchimi could be prepared by fermenting for 11 to 30 days at 0.5% jasoja concentration per radish.

• 한국식품영양학회지
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• 제32권5호
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• pp.494-503
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• 2019

The purpose of this study was to investigate the quality and antioxidant properties of three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria. During the fermentation, the pH was lowered and the titratable acidity increased. The viable cell counts of lactic acid bacteria increased 8.44-9.62 log CFU/g. Organic acid content (especially lactic acid) of sweet potatoes increased by fermentation. Also, ${\gamma}$-Aminobutyric acid increased more than 8.6 times by fermentation in all samples. The total polyphenol and flavonoid contents of sweet potato, showed insignificant changes in all samples by fermentation. ABTS radical scavenging activity of all samples slightly decreased by fermentation, but not significantly. DPPH radical scavenging activity decreased slightly by fermentation except Shinyulmi. However, when compared with the varieties, Shinjami showed the highest activity. The reducing power of Shinjami decreased slightly by fermentation, but activity was the highest among all samples. Based on these results, most of the chemical properties and functionality of fermented sweet potato are retained after fermentation, although some antioxidant activity decreases. We suggest that three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria can be used in various applications because of their effective functional properties.