Tylosin Production by Mutant Resistant to Oleic Acid

최두복,문옥란,윤미란,지성남,신대윤,Choi, Du-Bok,Choi, On-You,Moon, Ok-Ran,Yoon, Mi-Ran,Ji, Sung-Nam,Shin, Dae-Yewn Korean Society of Environmental Health 2005 한국환경보건학회지 Vol.31 No.5

Streptomyces fradiae로부터 Tylosin을 효율적으로 생산하기 위해 지방산 내성균주을 분리 했다. 여러 지방산중에서 oleic acid 1.6 g/l 이상이 첨가될 때 세포 성장이 완전히 저해 되었다. 그러나 oleic arid 1.2 g/l에서 얻어진 TM-224-1 균주는 최대 균체농도와 tylosin 생산이 얻어졌다. 또한 oleic acid 소비속도는 parent strain 비해 3.8배 증가했다. Oleic acid 내성균주, TM-224-1 균주와 parent strain을 이용해서 jar fermentor에서 균체농도, tylosin 생산, 그리고 rapeseed oil 소비를 표준조건하에 5일동안 비교하였다. TM-224-1 균주을 이용할 경우 균체 농도는 초기에 parent strain비해 증가했으나 배양중반부터는 감소하기 시작했다. rapeseed oil 소비의 경우는 거의 비슷했다. 그러나 Tylosin 생산 수율은 parent strain 비해 약 3.2배 증가했다. When rapeseed oil as the carbon source was used for tylosin production from Streptomyces fradiae TP-1239 was very sensitive to oleic acid. Cell growth was restrained by adding 0.8 g/l of oleic acid to the culture broth. Mutant strain TM-224-1 resistant to 1.2 g/l of oleic acid was obtained by screening in solid and liquid media containing oleic acid. The uptake rate of oleic acid by TM-224-1 was approximately 3.8 fold higher than the parent strain. For comparing the TM-224-1 and the parent strain, batch cultures were carried out in a jar fermentor. Cell growth of TM-224-1 strain was higher than the parent strain after two days of culturing. However, after four days of culturing, it was similar to that of the parent strain. The amount of rapeseed oil consumed by TM-224-1 and the parent strain were 60.5 and 78.2 g/l, respectively. The production and yield of tylosin was aproximately 2.0 and 3.2 fold higher than the parent strain, respectively. From these results, it was concluded that this mutant, which was resistant to oleic acid, has improved tylosin production.

Optimization for Phosphorus Remove by Loess Ball Using Chromobacterium

최두복,이춘범,차월석,Choi Du Bok,Lee Choon-Boem,Cha Wol-Suk Korean Society of Life Science 2005 생명과학회지 Vol.15 No.4

담체인 황토볼와 Chromobacterium WS 2-14을 이용하여 F-STEP공정(혐기${\rightarrow}$ 호기${\rightarrow}$ 무산소)에서 실제폐수에 존재하는 인산을 효율적으로 제거하기 위해 최적 황토볼 크기 및 소성 온도, 폐수의 초기 pH,폐수의 초기 인산염 농도, 운전온도, 그리고 통기를 검토했다. 최적 조건은 다음과 같다. 황토볼 크기 및 소성 온도, $2\~4mm,\;960^{\circ}C$; 실페수의 초기pH, 6.0; 실페수의 초기 인산 농도, 5.0mg/1. 운전온도, $30^{\circ}C$; 그리고 통기, 5.0L/min등이 얻어졌다. 그리고 최적 운전조건을 이용해서 pilot test을 65일 동안 진행했다. 인산 평균 제거율은 $92.0\%$였고. 또한 최종 유출수에서 COD와 BOD의 평균 제거율은 각각 77.1와 $74.2\%$였으며, SS의 경우는 평균 제거율이, $86.4\%$였다. 이상의 결과로부터 황토볼을 담체로 이용한 Biofilter System은 실제폐수에 존재하는 인산 제거 가능성을 암시했다. To investigate factors affecting the removal of phosphorus from the practical wastewater in the F-STEP PROCESS using a loess ball and Chromobacterium WS 2-14, first, the loess ball size and calcining temperature, initial pH, initial phosphorus concentration, working temperature, and aeration were studied. A $2\~4mm$ of loess ball made at $960^{\circ}C$ of calcining temperature was the most suitable one for the removal of phosphorus. When the initial pH was increased from 3.0 to 6.0, the removal efficiency of phosphorus was increased. Especially, at 6.0 of initial pH, the maximum removal efficiency of phosphorus was $88.7\%$. The maximum removal efficiency of phosphorous was gained, 1.8mg/h when the initial concentration of phosphorous was 5.0mg/1. When the operating temperature was $30^{\circ}C$, the maximum removal efficiency of phosphorus was obtained. In the case of aeration, when it was increased from 0.5 to 5.0L/min, the removal efficiency of phosphorus was increased. On the other hand, above 7.0 L/min, the removal efficiency of phosphorus did not increased. Using the optimum operation conditions, pilot tests for the effective removal efficiency of phosphorus were carried out for 65 days. The average removal efficiency of phosphorus was $92.0\%$. The average removal efficiency of COD, BOD, and SS were 77.1, 74.2, and $86.4\%$, respectively. from the results, it can be concluded that F-STEP PROCESS using loess ball might be useful process for phosphorus removal.

증숙된 더덕 추출물의 피부기능 개선 효과

이희경,최온유,최두복,최현숙,Lee, Hee-Gyeong,Choi, On-Yu,Choi, Du-Bok,Choi, Hyun-Suk 한국식품영양학회 2020 韓國食品營養學會誌 Vol.33 No.5

In this study, hot water and ethanol, acetone, and hexane extracts of the steamed Deodeok were investigated for use as raw materials for natural cosmetics. Hot water and ethanol, acetone and hexane extracts of steamed Deodeok did not indicate cell toxicity up to 300 ㎍/mL concentration in the MTT assay. The tyrosinase inhibition effects of the ethanol extract were higher than the ascorbic acid. The efficacy of the steamed Deodeok's ethanol extract on the elastase inhibition was similar to that of quercetin at higher concentrations. In conclusion, water, ethanol, acetone and hexane extracts of the steamed Deodeok indicated strong possibility as a whitening and anti-wrinkle functional cosmetic ingredient. Among them, the steamed Deodeok's ethanol extract, which showed excellent activity, is highly available because it has high safety compared to other organic solvent extraction methods used in cosmetics, and has minimal irritation to the skin.

증숙 더덕 에탄올 추출물에 대한 항산화·항균 활성

이희경,최온유,최두복,최현숙,Lee, Hee-Kyung,Choi, On-Yu,Choi, Du-Bok,Choi, Hyun-Suk 한국식품영양학회 2021 韓國食品營養學會誌 Vol.34 No.1

This study was investigated the contents of total polyphenol, flavonoids and antioxidant and antimicrobial activities of Codonopsis lanceolata extracts according to different steaming times. The contents of total polyphenol and flavonoid proportionally increased from 6.45 mgGAE/g to 18.26 mgGAE/g and 2.01 mgRE/g to 6.12 mgRE/g according to ethanol extracts at EDS7. DPPH radical scavenging activity was found to have been 15.26~65.2% and showed the highest level of antioxidant activity at EDS7 was 65.2%. The activity of ABTS radical scavenging and SOD-like activity were also the same result. DPPH and ABTS radical scavenging activity was related to the number of steaming, and the scavenging activity was increased up to 7 times of steaming. The antimicrobial activity of EDS7 had strong antioxidant activity. Antimicrobial activities were examined against 5 microorganisms related to pathogens and food poisoning. The antimicrobial Activity was different depending on the bacteria, but it was effective at the concentration of 300 mg/mL rather than 150 mg/mL. These results showed that Codonopsis lanceolata extracts with a different number of steaming would be conducted to confirm the possibility of developing antimicrobial and antioxidant. It will be helpful in the study of component analysis of Codonopsis lanceolata extracts processed products.

Hybrid SPR 접합을 적용한 이종소재 인장전단에 관한 연구

유관종(Kwan-jong Yu),최두복(Du-bok Choi),김재열(Jae-yeol Kim) 한국기계가공학회 2020 한국기계가공학회지 Vol.19 No.9

Self-piercing rivets are often used in the automotive industry, among other industries, as mechanical components to join multiple materials such as aluminum alloys. Self-piercing rivets have a strong sealing property, although there is considerable scope for their performance improvement. In this study, to enhance the performance of self-piercing rivets, the hybrid self-piercing riveting (SPR) technique, using the existing SPR and structural adhesive, was proposed. Moreover, heterogeneous material specimens subjected to the hybrid SPR technique were manufactured and tested. The joint strength of the test pieces of different materials was evaluated through finite element analyses.

해상죽 추출물의 성분 및 생리 활성에 관한 연구

박승규(Seung-Kyu Park),최두복(Du-Bok Choi),조훈(Hoon Cho) 대한환경위생공학회 2008 대한환경위생공학회지 Vol.23 No.2

The purposes of this study were to investigate the effects of bamboo (SasacoreanaNakai)extracton chemical characteristics and biological activities. pH ranges of bamboo extract using 'water and ethanol were between 5.2 and 6.1. The concentration of total phenol compounds using ethanol extract was 0.51%, which was about 2.0 fold higher than that of water extract. The mineral concentrations were order of K, Mg, Ca. and Na, respectively. The nitrite scavenging ratio of bamboo extract using ethanol was 20.4% in vitro. In the case of bamboo extract using water, it was 18.0%. Especially, the maximum nitrite scavenging ratio was obtained at pH 1.5. On the other hand, when pH was increased from 3.0 to 6.0, the nitrite scavenging ratio was decreased from 16.2% to 3.0%. The antioxidant activity of bamboo extract in vitro was increased from 100 to 160% when bamboo extract using ethanol was increased from 10 to 50μL. These results suggest that the bamboo extract of Sasa coreana Nakai using ethanol can be used in bioactive and functional material.

정제과정에 따른 대나무기름의 물리화학적 특성 성분에 관한 연구

니명순 ( Myung Sun Na ),최현숙 ( Hyun Suk Choi ),이명렬 ( Myung Yul Lee ),류성렬 ( Seong Ryeol Ryu ),박승규 ( Seung Kyu Park ),최용덕 ( Yong Deok Choe ),박옥란 ( Yu Lan Piao ),최두복 ( Du Bok Choi ),신대윤 ( Dae Yewn Shin ) 한국공업화학회 2008 공업화학 Vol.19 No.1

식품류를 이용한 방사선 방호 효과

김종수(Jong-Soo Kim),안병권(Byeong-Kwon Ahn),최현숙(Hyun-Suk Choi),최두복(Du-Bok Choi),염정민(Jung-Min Yeom),김숭평(Soong-Pyung Kim),이인성(In-Sung Lee),조미자(Mi-Ja Cho),차월석(Wol-Suk Cha) 한국생물공학회 2015 KSBB Journal Vol.30 No.1

Radiation causes various pathophysiological alterations in living animals, and it causes death at high doses by multiple mechanisms, including direct DNA damage and indirect oxidative stress. The search for useful radioprotectors has been an important issue in the field of radiation biology. Ideal radioprotectors should have low toxicity and an extended window of protection. As many synthetic compounds have toxic side effects, the natural products have attracted scientific attention as radioprotectors. Natural products that have been recently shown to be effective with various biological activities were found to have radioprotective effect. The aim of this review is to summary the recent research of the radioprotective effects of natural foods, especially focused on the glycobiological properties of mushrooms.

추출용매에 따른 함초 추출물의 피부미용 효과

김연순 ( Youn Soon Kim ),안병권 ( Byeong Kwon Ahn ),김란 ( Ran Kim ),최두복 ( Du Bok Choi ) 한국공업화학회 2011 공업화학 Vol.22 No.1

본 연구는 함초를 이용하여 기능성 화장품 개발을 위한 기초자료를 얻기 위해 추출용매에 따른 함초 추출물의 항산화 활성, tyrosinase 저해활성, elastase 저해활성, collagenase 저해활성을 검토 하였다. 여러 아미노산 중에서 glutamic acid이 가장 높았고, 그 다음으로는 proline, alanine, y-amino-n-butyric acid, arginine 순이였다. 폴리페놀 함량 및 항산화 효과는 ethyl acetate extract>n-butanol extract>hexane extract>hot water extract>ethanol extract 순이였다. 특히 ethyl acetate를 추출용매로 사용 할 경우 폴리페놀 함량이 31.6mg/mL였고, 항산화 활성은 82.6%였다. Tyrosinase활성 저해도는 ethyl acetate 추출물의 농도에 의존적으로 증가하였다. 특히 추출물 농도가 20에서 100mg/mL로 증가 할 경우 ty-rosinase활성 저해도는 15.2에서 98.2%로 증가 했다. Ethylacetate 추출물 농도가 20에서 100ug/mL 증가 할 경우 elastase 저해활성은 2.9에서 32.5%로 증가 되었고, collagenase 저해 활성은 3.8에서 29.7%로 증가 하였다. 이상의 결과는 함초 ethylacetate추출물이 화장품 기능성 소재로서 응용 가능성을 나타내었다. This study investigates the effect of Salicornia bigelovii extract on the activities of antioxidant, anti-wrinkle and whitening. Among amino acids, the glutamic acid concentration was the highest with an order of proline>alanine>y-amino-n-butyric acid>arginine. The total polyphenol concentration and antioxidant activity were an order of ethyl acetate extract>n-butanol extract>hexane extract>hot water extract>ethanol extract. Especially, when ethylacetate was used as extractant, the total polyphenol concentration and antioxidant activity were 31.6mg/mL and 82.6%, respectively. The inhibition activity of tyrosinase was increased with the increase concentration of ethylacetate extract. Especially, when the extract concentration was increased from 20 to 100mg/mL, it was raised from 15.2 to 98.2%. In the case of inhibition activities of elastase, and collagenase, they were also increased with the increase concentration of ethylacetate extract. When the extract concentrations were increased from 20 to 100ug/mL, they were enhanced from 2.9 to 32.5% and from 3.8 to 29.7%, respectively. The results show that the ethyl acetate extract of Salicornia bigelovii can be applied as sources for functional cosmetics and pharmaceuticals.

추출 용매에 따른 오죽(Phyllostachys nigra Munro) 추출물의 생리활성 효과

김연순 ( Youn Soon Kim ),조기안 ( Ki An Cho ),최두복 ( Du Bok Choi ) 한국공업화학회 2010 공업화학 Vol.21 No.1