• 한국약용작물학회지
• /
• 제19권6호
• /
• pp.472-477
• /
• 2011

The Forsythiae Fructus is an oriental medicine containing various lignans. In this study, the Forsythiae Fructus were extracted by hot water (Sample 1), hot water after bio-conversion using Lactobacillus strain (Sample 2-LP2, 2-LA, 2-LC, 2-LL, 2-BL and 2-LM) and 70% ethanol (Sample 3). Total polyphenol and flavonoid contents were improved by bio-conversion process using Lactobacillus strain, compared to water extract. Especially, sample 2-LL and 2-LA which had shown the high total polyphenol and flavonoid content in antioxidant activity. Also, sample 2-LL and 2-LA showed higher melanin generation inhibitory activity as of 55%, 53% in maximum extract concentration of $100{\mu}g/m{\ell}$. In the anti-inflammation test of the Forsythiae Fructus extracts, nitric oxide (NO) synthesis was inhibited. Specially, both 70% Forsythiae Fructus ethanol extract and sample 2-BL which have shown the relatively higher 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging and superoxide dismutase (SOD) like activities. In conclusion, the Forsythiae Fructus extracts with bio-conversion process has effect of skin whitening and anti-inflammation activity than other extracts. It could be used as a valuable materials for functional cosmetics.

• 한국미생물·생명공학회지
• /
• 제16권3호
• /
• pp.187-192
• /
• 1988

Cholesterol로부터 미생물전환 방법에 의한 4-androstene-3,17-dione(AD)의 생성에 대해 연구를 수행했다. 발효액중에 cholesterol의 용해도를 증가시키기 위해 ethanol을 용매로 사용하였는데, ethanol 농도가 2%(v/v)까지는 세균성장이 크게 저해되지 않았다. 미생물전환은 pH를 7.0으로 조절하고, 초기대수 증식기에 cholesterol을 첨가했을 때 효율적으로 AD가 생성되었다. AD 생성을 높이기 위해 cholesterol 첨가방법을 여러 가지로 변환시켰다. 즉, 최종 cholesterol 농도를 0.1% 하여 ethanol에 녹여 간헐적으로 첨가했을 때 가장 높은 수율을 얻었다. Cholesterol을 세번(전체 3g/$\ell$) 첨가했을 때 최종 전환수율이 65%에 도달한 반면, 같은 양의 cholesterol (3g/$\ell$)을 한번에 넣었을 때 40%의 생성수율을 얻었다.

• 신재생에너지
• /
• 제18권2호
• /
• pp.9-17
• /
• 2022

In this study, we used the Flux Balance Analysis (FBA) program to examine the behavior of hydrogen and organic acids according to seasonal changes in food wastewater collected from D city. The results showed that average hydrogen conversion rates in spring, summer, autumn, and winter were 1.06, 0.71, 1.21, and 1.13 mol H₂/mol of hexose_added, respectively, indicating a significantly lower hydrogen conversion rate in summer than in other seasons. This phenomenon is believed to occur because the carbohydrate concentration of the incoming food wastewater is low. In addition, Lactobacillus, the lactic acid-producing bacterium, was 21.3% in spring, 27.2% in summer, 17.5% in autumn, and 22.6% in winter. The most distinctive feature of the microbial community in summer was that 15.3% of the Ilyobacter was analyzed. It was confirmed that Ilyobacter, which is involved in the production of acetic acid and propionic acid, is closely associated with the tendency of increasing acetic acid and propionic acid and thus contributes to organic acid change. Clostridium, a hydrogen-producing bacterium, was 76.2%, 50.8%, 78.3%, and 74%, in spring, summer, autumn, and winter, respectively. It was confirmed that Clostridium dominates the microbial community by approximately 70% or more in all seasons except summer.

• Journal of Microbiology and Biotechnology
• /
• 제13권4호
• /
• pp.636-639
• /
• 2003

Entercbacter agglomerans 6L was isolated from citron (Citrus junos) peel by using an enrichment culture containing (+)-limonene. It was able to metabolize limonene and grew well ($A_{600}$:4.5) on limonene as a sole carbon source. E. agglomernas 6L was highly resistant to limonene toxicity, and grew to 1.0 optical density ($A_{600}$) even at 5% (v/v) of limonene in Luria-Bertani media. ${\gamma}-Valerolactone$ and cryptone were detected as the major metabolic products of limonene by E. agglomerans 6L.

• Journal of Microbiology and Biotechnology
• /
• 제31권5호
• /
• pp.740-746
• /
• 2021

Efficient cellulolytic enzyme production is important for the development of lignocellulose-degrading enzyme mixtures. However, purification of cellulases from their native hosts is time- and labor-consuming. In this study, a constitutive expression system was developed in Penicillium oxalicum for the secreted production of proteins. Using a constitutive polyubiquitin gene promoter and cultivating with glucose as the sole carbon source, nine cellulolytic enzymes of different origins with relatively high purity were produced within 48 h. When supplemented to a commercial cellulase preparation, cellobiohydrolase I from P. funiculosum and cellobiohydrolase II from Talaromyces verruculosus showed remarkable enhancing effects on the hydrolysis of steam-exploded corn stover. Additionally, a synergistic effect was observed for these two cellobiohydrolases during the hydrolysis. Taken together, the constitutive expression system provides a convenient tool for the production of cellulolytic enzymes, which is expected to be useful in the development of highly efficient lignocellulose-degrading enzyme mixtures.

• Journal of Microbiology and Biotechnology
• /
• 제21권5호
• /
• pp.494-502
• /
• 2011

Coenzyme $Q_{10}$ ($CoQ_{10}$) is a widely used supplement in heart diseases treatment or antioxidative dietary. The microbial production of $CoQ_{10}$ was enhanced by addition of solanesol and novel precursors recovered from waste tobacco. The novel precursors were separated by silica gel and identified as ${\alpha}$-linolenic acid (LNA) and butylated hydroxytoluene (BHT) based on the effect on $CoQ_{10}$ production and GC-MS. The effects of novel precursors on $CoQ_{10}$ production by Sphingomonas sp. ZUTE03 were further evaluated in a two-phase conversion system. The precursor's combination of solanesol (70 mg/l) with BHT (30 mg/l) showed the best effect on the improvement of $CoQ_{10}$ yield. A maximal $CoQ_{10}$ productivity (9.5 mg $l^{-1}$ $h^{-1}$) was achieved after 8 h conversion, with a molar conversion rate of 92.6% and 92.4% on BHT and solanesol, respectively. The novel precursors, BHT and LNA in crude extracts from waste tobacco leaves, might become potential candidates for application in the industrial production of $CoQ_{10}$ by microbes.

• Journal of Microbiology and Biotechnology
• /
• 제29권12호
• /
• pp.1993-2005
• /
• 2019

Thermophilic anaerobic digestion (TAD) is characterized by higher biogas production rates as a result of assumedly faster microbial metabolic conversion rates compared to mesophilic AD. It was hypothesized that the thermophilic microbiome with its lower diversity than the mesophilic one is more susceptible to disturbances introduced by alterations in the operating factors, as an example, the supply of nitrogen-rich feedstock such as poultry manure (PM). Laboratory scaled TAD experiments using cattle slurry and increasing amounts of PM were carried out to investigate the (in-) stability of the process performance caused by the accumulation of ammonium and ammonia with special emphasis on the microbial community structure and its dynamic variation. The results revealed that the moderate PM addition, i.e., 25% (vol/vol based on volatile substances) PM, resulted in a reorganization of the microbial community structure which was still working sufficiently. With 50% PM application, the microbial community was further stepwise re-organized and was able to compensate for the high cytotoxic ammonia contents only for a short time resulting in consequent process disturbance and final process failure. This study demonstrated the ability of the acclimated thermophilic microbial community to tolerate a certain amount of nitrogen-rich substrate.

• Asian-Australasian Journal of Animal Sciences
• /
• 제14권1호
• /
• pp.54-60
• /
• 2001

A study was conducted to assess the nutritive value of two diets based on a low-energy variety of wheat, RAC C1 and their effects on intestinal mucosal structure and function in broiler chickens. The diets were fed with or without microbial enzyme supplement to male and female broiler chickens. The digesta viscosity was reduced (p<0.001) through supplementation with a microbial enzyme in male and female chicks. Enzyme supplementation also improved the dietary apparent metabolizable energy content (p<0.001) and had slight but non-significant positive effects on chick growth and feed conversion ratio. Intestinal mucosal structure and enzyme function were not affected by microbial enzyme supplement. Male chicks consumed more feeds (p<0.001), attained higher final body weight (p<0.001) and were more efficient at feed utilization (p<0.01) than the female chicks. Except for duodenal villus surface area and ileal protein content, intestinal mucosal structure and enzyme activities were similar between the two sexes and dietary treatment groups. The study showed an improvement in the nutritive value of the diets in the presence of the microbial enzyme supplement.

• 한국수소및신에너지학회논문집
• /
• 제32권6호
• /
• pp.506-513
• /
• 2021

The use of fossil fuels is a major contributor to the increase atmospheric greenhouse gas emissions. As such problems arise, interest in new and renewable energy devices, particularly fuel cells, is greatly increasing. In this study, various characteristics of mixed strains were observed in wastewater collected by the Jeonju Environment Office to investigate the effects of microorganisms on voltage generation and voltage generation of substrates, electrode materials, electrons, electron transport media, and ash microbial fuel cells. As a result of separately measuring the voltage generated during inoculation, the inoculation voltage of Escherichia coli K12 (E. coli K12) was 0.45 V, and the maximum inoculation voltage of the mixed strain was 1.2 V. Thereafter, voltage values were collected using a digital multimeter and the amount of voltage generated over time was measured. In the case of E. coli K12, the maximum voltage reached 0.45 V, and the cell voltage was maintained above 0.23 V for 140 hours. In contrast, for the mixed strain, the maximum voltage reached 1.2 V and the voltage was slowly decreased to 0.97 V. In addition, the degree of microbial adsorption to the electrod surface after the inoculation test was confirmed using a scanning electron microscope. Therefore, these results showed the possibility of purifying pollutants at the same time as power generation through the production of hydrogen ions using microorganisms and wastewater.

• KSBB Journal
• /
• 제14권2호
• /
• pp.205-211
• /
• 1999

본 연구에서는 A.cycloclast ATCC 21921 균주를 사용하여 $\gamma$-butyrobetaine으로부터 L-carnitine을 생산하는 최적 조건에 대한 연구를 수행하였다. 배양액 내에 $\gamma$-butyrobetaine 만을 포함하였을때는 최대 L-carnitine 생산량이 29g/L이었고 전환수율도 30.9 mol%로 매우 낮았다. L-carmtine 생산에 미치는 탄소원의 영향을 관찰한 결과 glycerol을 첨가할 경우 L-carnitine 생산량이 4.6g/L 그리고 전환수율이 88.2 mol%로 $\gamma$-butyrobetaineaks을 포함하였을 때보다 월등히 향상되었다. Betaine, chohne와 같은 quaternary ammonium compounds 들이 L-carnitine 생산에 미치는 영향을 조사해본 결과, 이들에 의하여 L-carntine 생산 속도가 빨라지고 전환수율도 증가함을 알 수 있었다. 한편, 기질인 $\gamma$-butyrobetaine 농도 3% 이상에서 세포 생장은 저해되고 L-carnitine 생산은 기질 농도 2-3%에서 가장 우수함을 알 수 있었다. 본 연구에서 구한 최적 생산 조건, 다시 말해서 glycerol과 choline을 배양액에 포함하고 기질의 농도를 2%^로 하여 플라스크에서 회분식 배양을 하였을 때, 배양 4일 만에 최대 7.2g/L의 L-carrutine을 생산할 수 있었고 이때 $\gamma$-butyrobetaine으로부터 L-carnitine에로의 전환수율은 98.7mol%이었다.