Enhanced cold active lipase production by metagenomic library recombinant clone CALIP3 with a step-wise temperature and dissolved oxygen level control strategy

A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen（DO） on cold active lipase production by batch culture of metagenomic library recombinant clone（CAPL3） from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 ℃ for the first 15 h, and then switched to30 ℃. The cold active lipase activity and productivity reached 315.2 U·ml^-1and 8.08 U·ml^-1·h^-1, respectively,increased by both 14.5% compared to the results obtained with temperature controlled at 30℃. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34℃, 30% during 0–15 h;30 ℃, 30% during 15–18 h, and 30 ℃, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml^-1at 39 h, which was 28.8% higher than that achieved without temperature and DO control（275.3 U·ml^-1）.

An empirical research on strategic planning in public libraries of China's Mainland

Purpose: As an important issue, strategic planning in public libraries has been paid more attention in China recent years. However, a comprehensive and systematic research, especially strategic models based on empirical studies, is required in the public library strategic planning. The purpose of this research is to investigate the current practices and propose an appropriate reference and guidance of strategic planning in public libraries in China’s mainland.Design/methodology/approach: A questionnaire-based survey method is carried out to collect the views of public libraries staff at different levels in China’s mainland. The questionnaire is designed on the following four aspects toward strategic planning in public libraries: The attitude, the status quo, basic issues and the guides. The 882 valid questionnaires are processed by a statistic analysis to reflect the current practices of strategic planning in public libraries in China’s mainland.Findings: Our research results reveal that the unclear and confused understanding of the strategic planning still exist among the public libraries staff in China’s mainland. However, the majority of respondents still believe that the strategic planning in public libraries is significant and the library developments will be affected for lacking strategic planning. Moreover, it is considerable that the strategic plans are jointly made by independent agencies and public libraries, or by the public library itself. Also, guidelines and a set of softwares in strategic planning are needed.Research limitations/implications: The study was restricted to six main areas in China. A wider geographic sampling can preferable show the basic status of strategic planning in public libraries.The procedures of data collection would be another limitation. Nevertheless, case studies should be used in the further research.Originality: The importance of this research originates from a large number of first-hand data about strategic planning in public libraries in China’s mainland. The results provide extra perception into the future development of Chinese public libraries. The understanding obtained from this study will play a part in forthcoming evolution of this area of research.