Effect of propionic acid on citric acid fermentation in an integrated citric acid–methane fermentation process

In this study, an integrated citric acid-methane fermentation process was established to solve the problem of wastewater treatment in citric acid production. Citric acid wastewater was treated through anaerobic digestion and then the anaerobic digestion effluent (ADE) was further treated and recycled for the next batch citric acid fermentation. This process could eliminate wastewater discharge and reduce water resource consumption. Propionic acid was found in the ADE and its concentration continually increased in recycling. Effect of propionic acid on citric acid fermentation was investigated, and results indicated that influence of propionic acid on citric acid fermentation was contributed to the undissociated form. Citric acid fermentation was inhibited when the concentration of propionic acid was above 2, 4, and 6 mM in initial pH 4.0, 4.5 and, 5.0, respectively. However, low concentration of propionic acid could promote isomaltase activity which converted more isomaltose to available sugar, thereby increasing citric acid production. High concentration of propionic acid could influence the vitality of cell and prolong the lag phase, causing large amount of glucose still remaining in medium at the end of fermentation and decreasing citric acid production.     

Skin aging caused by intrinsic or extrinsic processes characterized with functional proteomics

The skin provides protection against environmental stress. However, intrinsic and extrinsic aging causes significant alteration to skin structure and components, which subsequently impairs molecular characteristics and biochemical processes. Here, we have conducted an immunohistological investigation and established the proteome profiles on nude mice skin to verify the specific responses during aging caused by different factors. Our results showed that UVB‐elicited aging results in upregulation of proliferating cell nuclear antigen and strong oxidative damage in DNA, whereas chronological aging abolished epidermal cell growth and increased the expression of caspase‐14, as well as protein carbonylation. Network analysis indicated that the programmed skin aging activated the ubiquitin system and triggered obvious downregulation of 14‐3‐3 sigma, which might accelerate the loss of cell growth capacity. On the other hand, UVB stimulation enhanced inflammation and the risk of skin carcinogenesis. Collectively, functional proteomics could provide large‐scale investigation of the potent proteins and molecules that play important roles in skin subjected to both intrinsic and extrinsic aging.     

<Emphasis Type="Italic">Phialemoniopsis endophytica</Emphasis> sp. nov., a new species of endophytic fungi from <Emphasis Type="Italic">Luffa cylindrica</Emphasis> in Henan,China

During a survey of endophytic fungi in the cucurbit plants collected from Henan, China, a new species, Phialemoniopsis endophytica was isolated from the lower stem of Luffa cylindrica. It differs from other Phialemoniopsis species by its cylindrical to flask-shaped phialides, falcate conidia with blunt ends, ostiolate pycnidium-like conidiomata without marginal setae and ellipsoidal chlamydospores. Multi-locus (ITS, LSU, ACT, and TUB) phylogenetic analysis confirmed that P. endophytica is distinct from other species. A synopsis of the morphological characters of the new species is provided.     

麻疯树G蛋白γ亚基JcAGG3基因的克隆及表达分析

从麻疯树c DNA中克隆到一个与拟南芥AGG3同源的基因,命名为Jc AGG3。该基因开放阅读框为834bp,编码277个氨基酸,软件预测等电点为8.61,分子质量为30.514k Da。亚细胞定位预测显示其定位于细胞质膜上。在该基因的顺势作用元件上发现了与胚乳发育、激素调节、光响应和逆境胁迫相关的启动元件。荧光定量PCR(q PCR)检测发现,Jc AGG3在根、茎、叶和种子中均有表达,在发育中的种子中表达量最高,幼叶中的表达量显著高于老叶,在茎中只检测到极微量的表达;对麻疯树的幼苗进行黑暗处理后Jc AGG3基因表达显著下调,脱落酸(ABA)和干旱胁迫处理下Jc AGG3表达量显著增加。