http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Asymmetrie synthesis of unnatural amino acids using transaminase technology
조병관,주황수,김병기 한국공업화학회 2001 한국공업화학회 연구논문 초록집 Vol.2001 No.-
Transaminases are valuable enzymes For the production oi optically pure unnatural amino acids, chiral amines and many D-amino acids through asymmetric synthesis or kinetic resolution. However, although transaminases have appropriate characteristics such as rapid reaction rates, broad substrate specificity and no requirement for external cofactor regeneration, the frequently cited drawback is the equilibrium constant for the reaction. We screened microorganisms having asymmetric synthesis activity for the production of L-2-amino-4-phenylbutyric acid (L-APBA) from 2-oxo-4-pTienyTbutyric acid (OPBA) using L-aspartic acid (L-ASP) as amino donor from soil samples. Among them, we have selected one microorganism showed the highest acceptor specificity to OPBA and the lowest specificity to pyruvate as amino acceptor. To characterize screened transaminase, we carried out purification of this transaminase. Using partially purified transaminase, we found that this transaminase also foHows ping-pong bi-bi mechanism and shows excellent stability at 37℃. Based on the substrate specificity study, this transaminase appears to be a kind of aromatic transaminases (ArAT). We tried to produce L-APBA at high concentration of OPBA using fed-batch type reaction.
Effects of SNS Characteristics on SNS Engagement and Consumer Brand Engagement
조병관,신향숙 한국프랜차이즈경영학회 2020 프랜차이즈경영연구 Vol.11 No.2
Purpose: Social Network Sites(SNS) have been grown up as a public communication channel consumer frequently participate in. Most of food service brands are utilizing social media for advertising recently. As a result of SNS marketing, food service brands anticipate positive outputs from SNS engagement and consumer brand engagement so that we need to verify structural relationship among SNS characteristics, SNS engagement and consumer brand engagement. Research design, data, and methodology: This study identifies that SNS characteristics have effects on SNS engagement and examines relationship between SNS engagement and behavioral engagement. We conceptualize SNS characteristics as information quality, hedonic level and interaction. Furthermore, SNS engagement is composed of SNS participation, positive word of mouth(WOM). In order to verify the purposes of this research, research model and hypotheses were developed. All constructs were measured with multiple items developed and tested in the previous studies. Sample data were collected from 433 online survey panels and analyzed by using SmartPLS 3.2.9. Result: The findings of this research are as follows. First, information quality is positively related with SNS participation. Hedonic level and interaction have impacts on SNS participation and positive WOM respectively. Second, SNS participation has positive effects on positive WOM. Third, both SNS participation and WOM influence behavioral engagement respectively. Conclusions: The implications demonstrate that SNS characteristics such as information quality and hedonic level and interaction exert effects for consumer to participate in SNS brand page. Meanwhile, hedonic level and interaction influence on positive WOM but information quality doesn’t. SNS participation and positive WOM affect consumer to engage in specific brand behaviorally as well. Therefore, food service brand marketer is required to manage SNS information quality and hedonic level and interaction among members to encourage SNS participation and positive WOM. As SNS participation and positive WOM increases behavioral engagement of consumer, marketer needs to incentivize SNS participation and look after situation of positive WOM and respond swiftly.