Nutrition and bioprocess development for efficient biosynthesis of an antitumor compound from marine-derived fungus

An integrated nutrition and bioprocess strategy was developed for improving the biosynthesis of an antitumor compound, 1403C, by a marine-derived fungus, Halorosellinia sp. (no. 1403). First, statistical design strategies were synthetically applied to optimize the nutritional composition. The resulting 1403C production reached 2.07 g/l, which was 143.5 % higher than the original production. However, it only produced 0.44 g/l of 1403C in 5-l bioreactor fermentation. Thus, the operating parameters including culture pH, dissolved oxygen, agitation speed, impeller type and inoculum level were considered to improve the fermentation process, and an effective control strategy for 1403C production by Halorosellinia sp. submerged in a 5-l bioreactor was established. When inoculating 0.22 g/l dry biomass, controlling dissolved oxygen not lower than 30 % during the growth phase but ranging between 30 and 40 % during the stationary phase, using a double-layer six-flat-blade Rushton disc turbine agitated at 400 rpm, keeping short-term low pH and rapid-rising pH with glucose starvation, the highest 1403C production was finally obtained at 1.32 g/l, which was promoted by 200 % compared to before optimization. Fermentation scale-up was finally performed in a 500-l bioreactor, and 1403C production of 1.09 g/l was obtained.     

Responses of macrophages against Salmonella infection compared with phagocytosis

To explore the responses of host cell after infection with live Salmonella compared with phagocytosis to dead bacteria, the responses of mouse macrophage after infection with Salmonella enteritidis C50041 and the fixed C50041 (C50041-d) were analyzed. Results indicated that the cytotoxicity induced by C50041 was stronger than C50041-d. Similar changing trends of mitochondrial membrane potential, intracellular concentration of calcium ions, reactive oxygen species and nitric oxide were found between C50041 and C50041-d infection. But the cell responses against C50041 were earlier and stronger than C50041-d. LC3 expression of macrophage induced by C50041 was lower than C50041-d. C50041 significantly inhibited the production of tumor necrosis factor and interleukin (IL)-6. Whereas intracellular caspase-1 activation and IL-1β release induced by C50041 were stronger than C50041-d, caspase-1 activation and IL-1β release are the innate defense responses of macrophage. Therefore, it will be beneficial to explore the use of this pathway in the control of Salmonella infection.     

Development and characterization of 14 novel microsatellite markers for an invasive goby (Tridentiger bifasciatus) in water transfer system

Genetic patterns observed among populations by neutral molecular markers is a major method used to reconstruct the invasion history of invasive species. The Shimofuri goby (Tridentiger bifasciatus) has invaded several lakes along the East Route of the South-to-North Water Transfer Project, China (ENST). However, neutral molecular markers for this goby are not currently available. In this study, fourteen novel polymorphic microsatellite loci were developed through next generation sequencing technology. These markers were also tested in an invasive population (Nansi Lake, a storage lake of ENST) consisting of 54 individuals. The average number of alleles per locus was 7.6 and ranged from 4 to 13. The average H_o was 0.587 and ranged from 0.404 to 0.852, and the average H_e was 0.733 and ranged from 0.564 to 0.851. The average PIC per locus was 0.689 and ranged from 0.521 to 0.824. Four markers (TB4, TB65, TB66 and TB26) were found to deviate from HWE after correction following the False Discovery Rate method. Null alleles were found in four loci (TB11, TB65, TB66 and TB26). These highly polymorphic microsatellite markers are useful for further study to reconstruct invasion history of Shimofuri goby.     

Alleviative effects of nitric oxide on Vigna radiata seedlings under acidic rain stress

Molecular Biology Reports - Although nitric oxide (NO) is a key regulatory molecule in plants, its function in plants under conditions of simulated acid rain (SAR) has not been fully established...     

硒与内生真菌对中华羊茅生长和代谢产物的影响

[目的] 探讨亚硒酸钠和内生真菌对中华羊茅生长和代谢产物的影响。[方法] 采用气相色谱-质谱联用仪检测中华羊茅两个地理种群带菌（E+）和不带菌（E-）植株地上部分和根系的非靶标代谢产物,利用单因素方差分析（LSD）显著性统计挖掘处理间的差异性代谢产物。[结果] 从地理种群海北（HB）和玉树（YS）植株中分别鉴定出206种和205种化合物,地上部分和根系中代谢产物存在较大的差异性,根据显著性统计检验P<0.001分别从地理种群HB地上部分、HB根系、地理种群YS地上部分、YS根系筛选出差异性代谢物27种、42种、40种、33种,这些差异性代谢物主要是一些含氮化合物、碳水化合物和有机酸。HB地上部分与HB根系共同差异性代谢物9种,YS地上部分与YS根系共同差异性代谢物8种,HB地上部分与YS地上部分共同差异性代谢物5种,HB根系与YS根系共同差异性代谢物14种。地理种群HB内生真菌极显著增加植物地上部分和根系中tyrose含量（P<0.001）,加硒促进E+和E-地上部分和根系α-ketoisocaproic acid含量极显著上升（P<0.001）,加硒和内生真菌极显著积累地上部分和根系aspartic acid含量（P<0.001）。加硒极显著提高地理种群YS E+和E-地上部分和根系α-ketoisocaproic acid和acetol含量（P<0.001）。[结论] 中华羊茅两个地理种群地上部分和根系非极性代谢物存在较大的差异性,亚硒酸钠和/或内生真菌能提高一些代谢产物的含量。     

Comparative Metabolomics Analysis between Red- and White-Flowered Common Buckwheat Cultivars

Common buckwheat (Fagopyrum esculentum), a specialty crop in southwest China, is not only used as a supplement to primary grain crops but also to produce beverages, such as tea and wine. To fully exploit the products made from common buckwheat flower, ultra-performance liquid chromatography–electrospray ionization– tandem mass spectrometry (UPLC–ESI–MS/MS) was conducted to analyze the metabolites in red- (‘Guihong 2’) and white-flowered (‘Fengtian 1’) buckwheat cultivars. A total of 784 metabolites were identified of which flavonoids were the largest group with 191 components, followed by organic acids and derivatives (126), and amino acids and derivatives (95). Besides, dozens of phenylpropanoids, nucleotides and derivates, lipids, alkaloids as well as several kinds of indole derivatives and sterides were detected. Among these rich varieties of metabolites, 24 metabolites were only detected in the red flower that mainly included 8 anthocyanins and 6 flavones, while 22 metabolites were only detected in the white flower, which mainly contained 5 lipids, 5 flavonoids, and 5 organic acids and derivatives. Our results enrich the metabolites’ information of buckwheat and may be helpful for the exploitation of products from common buckwheat flowers.