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Teramethylpyrazine (TMP) is a pyrazine alkaloid with a variety of pharmacological effects and widely used in clinical practice. In this study, Monascus strain M-3 with high TMP and low citrinin productions was screened from red yeast rice collected from different areas of Fujian province in China. Monascus strain M-3 was further identified through molecular biological methods based on the sequencing of different gene regions. Results showed that primer set of β-tubulin-F/β-tubulin-R targeting the β-tubulin gene was more suitable for the identification of Monascus strain M-3. Based on comparative analysis of the results obtained by different primer sets, Monacus strain M-3 was finally identified as Monascus purpureus. Then, the composition of culture medium and liquid state fermentation conditions of Monacus strain M-3 were optimized by single-factor experiment and central composite design of response surface methodology, with the purpose of optimizing the TMP productions. The optimum composition of culture medium and liquid state fermentation conditions are as follows: starch 5.1%, peptone 3.51%, Mg2SO4 0.1%, NaNO3 0.2%, KH2PO4 0.25%, fermentation temperature of 28.23 °C, fermentation time of 9 d, shaker speed of 180 r/min, inoculum size of 7.21% and loading volume of 100 mL/250 mL triangular flask. Under the optimum composition of culture medium and liquid state fermentation conditions, the TMP production of Monacus strain M-3 can reach 13.49 µg/mL. This study is expected to provide a new approach of TMP production through biosynthesis by Monascus strain, and promote the further development of functional foods or medicines from Monascus fermentation products.

From two aspects, namely the sensitivity of regional economic system to internal and external interference, and its resilience, we establish the evaluation indicator system of fragility of the economic system in Poyang Lake Ecological Economic Zone, and evaluate the internal differences in fragility of the regional economic system, using set pair analysis method. The results show that there is a great difference in fragility of the economic system between different administrative units; the difference in resilience is the major factor responsible for difference in fragility of the economic system in various cities and counties within the region; according to the difference in fragility characteristics, we conduct classification as follows: Nanchang City is a low-sensitivity and high-resilience type; Jiujiang City is a high-sensitivity and high-resilience type; Jiujiang County, Xingzi County, Yongxiu County, Hukou County, Duchang County, Ruichang County, De'an Xian, Wuning County, Pengze County, Leping City, Dongxiang County, Fengcheng City and Gao'an City are a high-sensitivity and low-resilience type; other cities and counties are a low-sensitivity and low-resilience type.