• Microbiology and Biotechnology Letters
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• v.33 no.3
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• pp.200-206
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• 2005

A bacterium with high productivity of poly-$\gamma$-glutamic acid (PGA) was isolated from the traditional Korean seasoning, ChungKookJang. The 16s ribosomal RNA sequence of isolated strain showed 97.6, 98.9 and $90.3{\%}$ of similarity to those of Bacillus sp. WL-3, Bacillus subtilis; ENV1 and B amy-loliquefaciens (T), respectively. Accordingly, this bacterium was identified as a Bacillus sp. However, some biochemical characteristics of this strain were different from those of B. subtilis: D-xylose fermentation and glycogen utility were negative. Maximum production of PGA was achieved when it was grown aerobically in a culture medium containing glutamic acid ($3{\%}$) and fructose ($4{\%}$) as carbon sources. The volumetric yield of PGA reached up to 27 g/l in the optimum culture medium. These results suggest that the present strain can be applicable for industrial purposes such as a prototype strain for food or cosmetics industry.

• Journal of Dairy Science and Biotechnology
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• v.34 no.4
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• pp.231-237
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• 2016

Kefir is a probiotic food. Probiotics have shown to be beneficial to health, and are currently of great interest to the food industry. Hence, this study was carried out to evaluate the lactase activity of kefir-isolated lactic acid bacteria. Three strains, Lactobacillu kefiri DH5 isolated from the kefir grains and Bifidobacterium animalis subsp. Lactis and Bifidobacteria longum 720, commercial probiotic LAB, were fermented in 10% reconstituted nonfat dry milk suspensions and incubated at $37^{\circ}C$ for 48 h, and then analyzed for various saccarides by HPLC. The results showed that changes in the concentrations of lactose and galactose were significantly decreased and increased, respectively (p<0.05), but all 3 probiotic strains tested in this study showed no increase in glucose concentration during 48 h of incubation. Both DH5 and BL720 showed high lactase activities (p<0.05), whereas BLC exhibited the lowest activity. Additionally, all three lactic acid bacteria showed high tagatose, but did not show high xylose and sedoheptulose. Finally, DH5, a kefir-isolated LAB, may have similar characteristics and properties to typical Bifidobacterium spp. and showed higher lactase activity than commercial Bifidobacterium spp.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.97-102
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• 2003

Raw and washed spinaches were tested to evaluate the incidences of Aeromonas hydrophila, Escherichia coli O157:H7, Plesiomonas shigelloides, Pseudomonas aeruginosa, Salmonella spp., Shigella spp., Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Listeria monocytogenes, and Staphylococcus aureus. Four pathogenic bacteria were isolated from spinach samples, and identified by morphological and biochemical methods, including API and ATB identification systems. Isolates from MacConkey, Cereus Selective, Clostridium Perfringens, and Baird-Parker agar media were in 99.9, 99.8, 99.9, and 97.8% agreements with A. hydrophila, B. cereus, C. perfringens, and S. aureus at the species level, respectively. SET-RPLA revealed, among the five strains of S. aureus isolates, two produced type A enterotoxin. All five strains of B. cereus isolates produced enterotoxin as revealed with CRET-RPLA.

• Korean Chemical Engineering Research
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• v.50 no.1
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• pp.141-148
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• 2012

In order to study the utilization of brown seaweed Laminaria japonica as an alternative renewable feedstock for bioethanol production, the properties of acid hydrolysis and ethanol fermentation were investigated. The acid hydrolysis enhanced the final yield of fermentable sugars, which led great increase of ethanol productivity. The maximum yield of reducing sugars reached 135 mg/g-dry Laminaria japonica after 1.0N sulfuric acid-hydrolysis at $130^{\circ}C$ for 6 h. The Saccharomyces cerevisiae (ATCC 24858) could ferment $C_6$-sugars like glucose, galactose and mannose into ethanol, but not $C_5$-sugars like arabinose and xylose. Optimal fermentation time varied with sugars; 48 h for glucose, 72 h for galactose, and 96 h for mannose. Nevertheless, the ethanol yield from the hydrolysate reached 242 mg/g-dry Laminaria japonica after fermentation by the S. cerevisiae at $35^{\circ}C$ for 96 h, which corresponds to approximately 4 times more than the theoretical yield from total reducing sugars in the hydrolysates. It indicates that the non-reducing sugars or oligosaccharides dissolved in the hydrolysate played an important role in producing bioethanol. The ethanol concentration linearly increased from 2.4 to 9.2 g/L, while the ethanol yield per dry weight of biomass decreased from 242 to 185 mg/g, with increasing the ratio of biomass to acid solution from 1 to 5% (w/v). The bioethanol yield estimated was approximately 7,400~9,600 kg/ha/year, and indicated that Laminaria japonica is a promissing feedstock for bioethanol production.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.91-95
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• 2009

To examine physico-chemical properties of the polysaccharide extracted from liquid-cultured mycelia of Schizophyllum commune, each the polysaccharide was extracted with hot water treatment and then fractionated with ethanol, alkaline solution and ultrafiltration. And we determined carbohydrate contents, composition of amino acids, infra-red spectrum and viscosity. Carbohydrate contents of polysaccharide treated with ethanol and ultrafiltration were 72.0% and 62.3%, and proteins content were 15.3% and 32.0% respectively. The carbohydrate consisted of four monosaccharides and the protein contained 16 amino acids. The polysaccharide obtained from ultrafiltration was shown an absorption band characteristic of the ${\beta}$-glycosidic linkage by infra red spectra. These results suggest that the polysaccharide extracted from Schizophyllum commune showed the characteristics of proteinbounded polysaccharide, and it was ${\beta}$-glycosidic linkage with strong viscosity.

• Journal of Ginseng Research
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• v.30 no.1
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• pp.41-48
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• 2006

In the browning reaction of Korean ginseng, it appears that enzymatic and non-enzymatic browning reaction occurred In initial stage of steaming fresh ginseng at low temperature, and then non-enzymatic browning reaction followed in the drying period after steaming. Browning reaction of red ginseng occurred between $60{\sim}90$ min of steaming at $100^{\circ}C$, and browning pigments of red ginseng were mostly water soluble substances. The structural characteristics of water soluble browning reaction products(WS-BRPs) isolated from Korean red ginseng were showed the presence of hydroxyl, amide carbonyl and aliphatic methane groups. From sugar analysis it was identified that L and S-1, melanoidins isolated from red ginseng, contained two kinds of sugars, glucose and xylose, and the other melanoidin S-2 contained the previous and fructose. In order to find out pertinent methods for the acceleration of browning during ginseng processing, various treatment were made on fresh ginseng with sugars, amino acids and inorganic nitrogenous compounds and the extent of browning was measured. Among sugar tested, maltose resulted in the greatest acceleration of browning followed in decreasing order by glucose and lactose, whereas pentoses, fructose, sucrose and raffinose had negligible effect. A marked browning occurred in ginseng treated with basic amino acids, while the extent of browning was not greatly increased when ginseng was treated with aliphatic amino acids, hydroxyl amino acids, or acidic amino acids. The brown color intensity gradually increased with an increase of glucose concentration far up to 0.5M. L, S-1, and S-2 were found to have an ability to donate hydrogen to DPPH, and also they had anti-oxidative activity in the experiments of hydrogen peroxide scavenging, inhibitory activity in the formation of MDA from linoleic acid, auto oxidation of ok-brain homogenates, lipid peroxidation by the enzymatic and non-enzymatic system in liver microsome fraction, and mitochondrial fraction etc. The amounts of acidic polysaccharide(AP) in red ginseng were higher than those of wild and cultured Panax quinquefolius, Panax notoginseng as well as white ginseng (Panax ginseng). In white ginseng, the AP amount is no difference in root ages or sizes, also, the AP amount of ginseng body was similar to that of rhizome, but was higher than that of leaf and epidermis. Addition of red ginseng acidic polysaccharide(RGAP) increased production of nitric oxide(NO) and tumor necrosis factor (TNF)-$\alpha$ in the rodent macrophage cultures, and treatment of RGAP in vivo stimulated tumoricidal activities of natural killer (NK) cells.

• Microbiology and Biotechnology Letters
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• v.5 no.1
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• pp.18-23
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• 1977

Experiments were carried out to pursue the availability and the feasibility of utilizable cellulosic materials as substrate for the production of cellulosic single cell protein. The resuluts were obtained as fellows. 1. Effects of carbolydrates as a sole carton source on the growth of Cellulomonas flavigena KIST 321 were examined. The result showed that cellulose and xylose would be most utlizable for cell mass production. 2. Alkaline treated waste papers and clothes resulted in good growth of the organism than intact ones did. However the waste papers as substrate of cellulosic fermentation were not digestible, even if the meterial was treated with alkalies. 3. Rice straw, rape straw and panic grass appeared to be good substrates for the cell mass production. 4. Leaves were proved to be a good substrate for the cell mass production, but wood sawdust was hardly digested by merely alkaline treatment. 5. When cellulosic wastes as the substrate were examined into the concentration of alkaline solution, the result suggested that the best productivity of cell mass from cellulosic materials was obtained on treatment with 0.8∼1.0％ NaOH solution. 6. The productivity of cell mass was increased by washing out with water after alkaline treatment of newspaper, pine sawdust, lime sawdust and pine leaf.

• Korean Journal of Food Science and Technology
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• v.36 no.5
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• pp.800-803
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• 2004

Chemical components and physiological activities of acorn powders were investigated to develop functional food. Proximate components were 87.29% crude fiber, 1.18% crude fat, 0.84% crude protein, and 0.12% crude ash. Potassium was most predominant mineral, followed by phosphorus, calcium, magnesium, and sodium. Contents of unsaturated fatty acids, such as oleic, linoleic, and linolenic acids, were higher than those of saturated fatty acids. Water and 75% ethanol extracts of acorn powders showed higher absorbency at 285 nm. Water and 75% ethanol extracts exhibited antioxidative activity with $IC_{50}$ of 19.0 and $21.4\;{\mu}g/mL$, respectively, indicating they are the major biological component in acorn powders. Results suggest water extract of acorn can be used as new material for natural antioxidant and functional food.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.154-154
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• 2003

국내산 홍화씨를 부위별(Whole, Coat and Endosperm)로 분리한 후 추출용매, 볶음조건, 효소가수분해 등의 처리조건을 달리하여 추출된 추출물의 이화학적특성과 기능성성분 함량을 분석, 비교하였다. 홍화씨 부위별추출물의 고형분함량은 60%에탄올배유부분추출물이 11.29%로, 19$0^{\circ}C$, 30분 볶음처리배유추출물이 14.53%로, amyloglucosidase 처리배유추출물이 24.21%로 높은 고형분이 추출되었다. 총페놀함량은 추출용매의 에탄올농도가 증가함에 따라 증가하는 경향이었고, 80% 에탄올점질추출물이 965mg%로 가장 높았으며, 21$0^{\circ}C$, 30분 볶음처리껍질추출물이 756 mg%로, celluase처리껍질추출물이 1170mg%로 높은 함량이었다. 총플라보노이드함량은 80%에탄올전체추출물이 317 mg%로, 21$0^{\circ}C$, 30분 볶음 처리배유추출물이 488 mg%로, $\beta$-amylase 처리전체추출물이 554 mg%로 높은 함량이었다. 유리당 중 sucrose함량은 21$0^{\circ}C$, 10분 볶음처리배유추출물이 123.4 mg%로, 60%에탄올배유추출물이 57.0 mg%로, Celluase 처리배유추출물이 67.1 mg%로 가장 높은 함량이었고, 또한 glucose, fructose, xylose 및 arabinose 등도 함유하고 있었다. 유기산 중 citric acid 함량은 20%n 에탄올배유추출물이 243.3 67.1 mg%로, 21$0^{\circ}C$, 30분 볶음처리전체추출물이 76.3 mg%로, amyloglucosidase 처리배유추출물이 699.3 mg%로 가장 높은 함량이었고, 또한, oxalic, malic, succinic, acetic 및 fumaric acid 등도 확인되었다. Serotonin 화합물 중 serotonin- I 함량은 100% 에탄올껍질추출물이 431 mg%로, 21$0^{\circ}C$, 10분 볶음처리껍질추출물이 192 mg%로, amyloglucosidase 처리껍질추출물이 256 mg%로 가장 많았다. 또한, Serotonin-II함량은 100%에탄올껍질추출물이 763 mg%로, 17$0^{\circ}C$, 10분 볶음처리전체추출물이 312 mg%로, amyloglucosidase 처리껍질추출물이 456 mg%로 가장 많았다. Acacetin 함량은 80%에탄올배유추출물이 34.9 mg%로, 21$0^{\circ}C$, 30분 볶음처리배유추출물이 221.0 mg%로, amyloglucosidase 처리배유추출물이 27.8 mg%로 가장 많았다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.150.2-151
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• 2003

한국산 장뇌산삼의 열매, 잎, 줄기 및 뿌리를 -7$0^{\circ}C$ 동결건조 분말화시킨 시료에 대한 추출용매와 농도에 따른 유용성분의 함량을 비교, 분석하였다. 추출액의 당도는 잎과 줄기의 80% 에탄올추출액이 각각 22.58%와 22.53%로 가장 높았고, pH는 4.43-7.41 수준이었고, 갈변도는 흡광도가 잎과 뿌리 80% 에탄올추출액이 1.803과 1.085로 가장 높았다. 색도의 경우 L값는 줄기 100% 증류수추출액이 24.56, 열매 80% 메탄올추출액이 24.35로 가장 높았고, 뿌리와 잎 80% 에탄올추출액이 각각 17.47과 19.59로 가장 낮은 값을 나타내었다. a값은 잎100% 증류수추출액이 0.41로 가장 높았고, 줄기 80%메탄올추출 액이 -0.49로 가장 낮은 값을 보였다. b값은 줄기 80% 메탄올추출액이 3.69로 가장 높았고, 열매 100% 증류수추출액 이 0.45로 가장 낮은 값이었다. 주요 유리당은 sucrose, glucose 및 fructose 이었고, 유리당 총함량은 열매와 줄기 100% 증류수추출액이 각각 6733 mg/100g과 6142 mg/100g으로 가장 많은 량을 함유하였고, sucrose는 뿌리 80% 메탄올추출액 이 3673 mg/100g으로, glucose 및 fructose는 줄기 80% 에탄올추출액과 잎 80% 메탄올추출액에 각각 4283 mg/100g과 1897 mg/100g으로 높은 함유량을 나타내었다. 또한 잎과 줄기에는 xylose가 304-524 mg/100g 수준으로 함유되어 있었고, 뿌리에는 maltose가 소량 함유하고 있었다. 주요 유기산으로는 citric acid, tartaric acid 및 malic acid가 확인되었고, citric acid는 뿌리 80% 메탄올추출액이 1849 mg/100g으로 가장 높은 함량이었고, tartaric acid는 잎 80% 메탄올추출액이 3263 mg/100g으로 가장 높은 함량이었고, malic acid는 뿌리 80% 메탄올추출액이 1856 mg/100g으로 가장 높은 함량이었으며, 뿌리 80% 메탄올추출액에는 succinic acid, malonic acid 및 oxalic acid 등이 확인되었다. 유리아미노산은 L-Arginine, ${\gamma}$-Amino-n-butyric acid, Ethanolamine, L-Proline, $\beta$-Alanine 및 L-sarcosine 등 총 35종이 확인되었고, L-Arginine은 251-7379 mg/100g 수준으로 특히, 뿌리 80% 메탄올추출액에는 1319 mg/100g으로 총함유량의 79.13%로 매우 높은 함유량을 나타내었다. P, K, Na, Ca 및 Mg 등이 주된 무기질로 확인되었고, 그 중 P는 줄기 100% 증류수추출액에 15563 mg/100g으로 가장 높았고, K은 잎 80% 메탄을 추출액에 4952 mg/100g, Ca과 Na은 잎과 열매 100% 증류수추출액에 각각 3052 mg/100g과 1798 mg/100g, Mg은 잎 100% 증류수추출액에 950 mg/100g으로 매우 높은 함유량을 보였고, 또한 미량원소로는 Zn, Cu, Cr, Mn, Co, Mo, Fe 등이 함유되어 있었다.