Effect of Fermentation Conditions on L-Lactic Acid Production from Soybean Straw Hydrolysate

( Juan Wang ),( Qunhui Wang ),( Zhong Xu ),( Wenyu Zhang ),( Juan Xiang ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.1

Four types of straw, namely, soybean, wheat, corn, and rice, were investigated for use in lactic acid production. These straws were mainly composed of cellulose, hemicellulose, and lignin. After pretreatment with ammonia, the cellulose content increased, whereas the hemicellulose and lignin contents decreased. Analytical results also showed that the liquid enzymatic hydrolysates were primarily composed of glucose, xylose, and cellobiose. Preliminary experiments showed that a higher lactic acid concentration could be obtained from the wheat and soybean straw. However, soybean straw was chosen as the substrate for lactic acid production owing to its high protein content. The maximum lactic acid yield (0.8 g/g) and lactic acid productivity (0.61 g/(l/h)) were obtained with an initial reducing sugar concentration of 35 g/l at 30°C when using Lactobacillus casei (10% inoculum) for a 42 h fermentation period. Thus, the experimental results demonstrated the feasibility of using a soybean straw enzymatic hydrolysate as a substrate for lactic acid production.

One-pot preparation of LiFePO4/C composites

Juan Wang,Ji-Yu Li,Zhong-Bao Shao,Hong-Tao Fan,Hong-Qiang Ru,Shu-Yan Zang 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.2

A convenient one-pot method, called high-temperature high-energy mechanical force (HTHEMF), was successfully developed for the preparation of LiFePO4/C composites. Upon the combination of high-temperature with high-energy mechanical force, the whole synthesis process of this method is very simple and only involves two steps, the precursor preparation and the calcination step. The results of XRD, SEM, BET and electrochemical performance tests indicated that after calcination at 600 oC for 9 h, the LiFePO4/C composites have the best properties. The discharge capacity of the composites was 150.3mA h g−1 at 0.1 C. After 30 cycles test, the reversible capacity was 147mA h g−1 and the retention ratio to the initial capacity was 97.8%. The results indicated that LiFePO4/C composites with good properties can be obtained by one-pot HTHEMF method.

Genotypic analysis of degenerative Cordyceps militaris cultured in the pupa of Bombyx mori

Juan Yin,Xiang-Dong XIN,Yu-JieWENG,Shao-Hui Li,Jun-Qiang JIA,Zhong Zheng Gui 한국곤충학회 2018 Entomological Research Vol.48 No.3

The chemical composition and pharmacological effects of Cordyceps militaris are similar to those of Cordyceps sinensis, with the former undergoing greater development and utilization. Strain degeneration is a common phenomenon that occurs with high frequency during the subculturing of C. militaris, however, and the mechanism underlying strain degeneration remains unclear. In this study, we used touch‐down PCR to compare the ITS1 + 5.8S + ITS2, 18S, 28S and mating‐type (MAT) regions sequence of wild‐type and degenerated strains of C. militaris. We also used quantitative real‐time PCR to analyze expression levels of the CmMAT gene. Sequence analysis showed that the ITS1 + 5.8S + ITS2 and 28S regions of degenerated and wild‐type strains were completely identical, the 18S region of the degenerated strain contained seven single‐base mutations, including six base substitutions and one single‐base insertion. Compared with the wild‐type strain, the degenerated strain contained a deletion of the MAT1–2‐1 region, three base substitutions in the MAT1–1‐1 region, and a base substitution in the MAT1–1‐2 region that causes a glycine‐to‐valine amino acid substitution. Quantitative real‐time PCR analysis detected no CmMAT1–2‐1 gene expression in the degenerated strain, confirming the deletion of the CmMAT1–2‐1 gene. Expression levels of the CmMAT1–1‐1 and CmMAT1–1‐2 genes were significantly down‐regulated to only 7.5 % and 4.4 %, respectively, that of the wild‐type strain. These results indicate that 18S and MAT region mutations, as well as down‐regulated of CmMAT gene expression levels, may play important roles in C. militaris degeneration. This study provides a theoretical basis for further elucidation of the molecular mechanisms of C. militaris degeneration.

EFFECT OF SUBSTITUENTS IN THE IMIDAZOLIUM RING ON THE PERFORMANCE OF SOLID-STATE DYE-SENSITIZED SOLAR CELLS

Juan Li,ZHONG-SHENG WANG,KAI LV,HONG SUN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.5

Three solid-state imidazolium iodides have been designed and synthesized for use as all-solid-stateelectrolytes in solid-state dye-sensitized solar cells (ssDSSCs). The e®ect of substituents in theimidazolium ring on the ionic conductivity and solar cell performance of ssDSSCs has been inves-tigated. As compared to the methyl-ethyl-substituted imidazolium iodide, replacement of one alkylgroup (the methyl group) with an ester group increases the ionic conductivity and solar cell per-formance signi¯cantly, and further replacement of the other alkyl group (the ethyl group) with ahydroxyethyl group further increases the ionic conductivity and solar cell performance signi¯-cantly. A power conversion e±ciency of 7.45% has been achieved under the irradiation of simulatedAM1.5G solar light (100 mW cm? 2 ) with the ssDSSC using the hydroxyethyl and ester co-func-tionalized imidazolium iodide based solid-state electrolyte and a metal-free organic dye sensitizer.

Fructus mume Protects Against Cigarette Smoke Induced Chronic Cough Guinea Pig

Juan Xiang,Xiaodong Liu,Shan Zhong,Zhangfu Fang,Shuirong Shen,Jiaman Tang,Siqi Lai,Kefang Lai 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.2

Fructus mume was recorded in the Chinese Pharmacopoeia and traditional Chinese medical books for chronic cough, but the effect and related constituents are still unknown. Thus, we investigated the protect effects and the relevant constituents of F. mume in a guinea pig model with chronic cough induced by cigarette smoke (CS). The organic acids and polysaccharides in F. mume were detected by high performance liquid chromatography, gel permeation chromatography, and gas chromatography–mass spectrometry. The guinea pigs were orally administered with vehicle or the water extract of Fructus mume (FW) during the 14 days of CS exposure. Citric acid induced coughs were automatically measured by Buxco system. The differential cells in bronchoalveolar lavage fluid (BALF) and histopathological changes in lung tissue were assessed by hematoxylin and eosin staining. The tumor necrosis factor alpha (TNF-α) and interleukin-8 (IL-8) levels in lung tissue were detected via enzyme-linked immunosorbent assay. The mucus productions in tracheas were determined with Alcian blue-periodic acid Schiff staining. The results suggested relatively high concentration of citric acid, chlorogenic acid, and neochlorogenic acid in F. mume, and high proportion of galactose and glucose and lower molecular weight of polysaccharides. Administration of FW significantly reduced the cough frequency, decreased inflammatory cells in BALF and lung tissue, and attenuated the thickening of airway epithelium and submucosa compared with CS-exposure group. Moreover, the overproduction of TNF-α and IL-8 in lung tissues, and mucus in central airways of CS-induced guinea pigs was markedly inhibited by FW. The extract could also protect against CS exposure-induced chronic cough in guinea pigs by reducing coughs, airway inflammation, and mucus overproduction.

An Improved Method for Extracting Bacteria from Soil for High Molecular Weight DNA Recovery and BAC Library Construction

Juan Liu,Jingquan Li,Li Feng,Hui Cao,Zhongli Cui 한국미생물학회 2010 The journal of microbiology Vol.48 No.6

Separation of bacterial cells from soil is a key step in the construction of metagenomic BAC libraries with large DNA inserts. Our results showed that when combined with sodium pyro-phosphate and homogenization for soil dispersion, sucrose density gradient centrifugation (SDGC) was more effective at separating bacteria from soil than was low speed centrifugation (LSC). More than 70% of the cells, along with some soil colloids,were recovered with one round of centrifugation. A solution of 0.8% NaCl was used to resuspend these cell and soil pellets for purification with nycodenz density gradient centrifugation (NDGC). After purification,more than 30% of the bacterial cells in the primary soil were extracted. This procedure effectively removed soil contamination and yielded sufficient cells for high molecular weight (HMW) DNA isolation. Ribosomal intergenic spacer analysis (RISA) showed that the microbial community structure of the extracted cells was similar to that of the primary soil, suggesting that this extraction procedure did not significantly change the the soil bacteria community structure. HMW DNA was isolated from bacterial cells extracted from red soil for metagenomic BAC library construction. This library contained DNA inserts of more than 200 Mb with an average size of 75 kb.

“聲訓”說的歷史反思

鍾如雄(Zhong Ruxiong),胡娟(Hu Juan),劉春語(Liu Chunyu) 동아인문학회 2018 동아인문학 Vol.43 No.-

Many research have been done by previous scholars about the ‘acoustic explanations’ (a traditional exegetics terminology), however, there are still two unresolved problems, one of them is there is no strict definition of this term and the other is the theory has always been out of line with practice. Starts from a historical perspective, this article did an in-depth study of the formation process of theory and tried to clarify differences and connections between ‘acoustic explanations’ and ‘seeking meaning through sounds’. The article pointed out for the first time that ‘acoustic explanations’ is to directly interpret meaning through semantically related words while ‘seek meaning through sounds’ is to find out the original form of a character for those wrongly written or mispronounced characters in their written forms, the essence of it is to seek the characters through sound; ‘Seeking meanings through sound’ is to find the literal meaning with the help of the same/similar sounds.

Cytotoxic Isoflavanones from Uraria clarkei

Xiang-Zhong Huang,Xi-Shan Bai,Hui Liang,Chao Wang,Wen-Juan Li,Junming Guo,Zhi-Yong Jiang 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.5

Two new isoflavanones, (3R) 5,7,3',4'-tetrahydroxy-2'-methoxyisoflavanone (1) and (3R) 5',8-di-(γ,γ- dimethylallyl)-2',5-dihydroxyl-4',7-dimethoxyl-isoflavanone (2), were isolated from Uraria clarkei, together with two known compounds dalbergioidin (3), 5,7-dihydroxy-2',4'-dimethoxyisoflavanone (4). The structures involving the absolute configuration of the new compounds were well elucidated by MS, IR, UV, CD, 1D and 2D NMR analyses. Cytotoxicity of the four compounds were assessed, results suggested that compound 2 possessed well cytotoxic activity, against the Hela, K562, and HL60 cell lines with IC50 values of 28.0, 40.6 and 35.1 μM, respectively.

Efficacy of herbal medicine (Xuanfei Baidu decoction) combined with conventional drug in treating COVID-19:A pilot randomized clinical trial

Wu-zhong Xiong,Gang Wang,Juan Du,Wang Ai 한국한의학연구원 2020 Integrative Medicine Research Vol.9 No.3

Background: The aim of this study was to evaluate the clinical efficacy of Xuanfei Baidu Decoction (XBD) combined with conventional drug therapy compared with conventional medicine alone in patients with coronavirus disease 2019 (COVID-19). Methods: Forty-two patients with COVID-19 were randomly assigned to XBD plus conventional medicine (n = 22) and conventional medicine alone (n = 20). Both groups were treated for 1 week. The primary endpoint was the disappearance rate of main symptoms (fever, cough, and fatigue). Results: Compared with the conventional medicine, the disappearance rate of clinical symptoms such as fever, cough, fatigue and loss of appetite in the experimental group were significantly reduced (P < 0.05). The number of white blood cells and lymphocytes in the experimental group increased significantly (P < 0.05), which all returned to normal parameters. Meanwhile, the C-reactive protein and erythrocyte sedimentation rate in the experimental group were significantly reduced (P < 0.05). Conclusion: XBD combined with conventional medicine may significantly improve patient's clinical symptoms, increase the number of white blood cells and lymphocytes to improve immunity, and also significantly reduce C-reactive protein and erythrocyte sedimentation rate to play an anti-inflammatory effect. However, it needs to be confirmed by a large sample study.

Enzymatic Synthesis of Theanine with Escherichia coli γ-glutamyltranspeptidase from a Series of γ-glutamyl Anilide Substrate Analogues

Hong-juan Zhang,Wei-guo Zhang,Zhi-yuan Wang,Yue-ping Zhan,Li-sheng Xu,Jun-zhong Liu,Qian Liu,Qing-cai Jiao 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.2

In order to investigate the catalytic mechanism of Escherichia coli γ-glutamyltranspeptidase, ten para- and meta- substituted γ-glutamyl anilides were chemically prepared and employed as substrates to synthesize L-theanine to assay the activity of γ-glutamyltranspeptidase. The reaction was optimized for γ-glutamyl-p-nitroanilide. Key factors such as substrate specificity, pH, temperature, and the substrate mole ratio were all investigated. Kinetic studies of the acyl transfer reaction were described and the Hammett plot was constructed. This study indicated that the ratelimiting acylation reaction of γ-glutamyltranspeptidase can apparently be accelerated by either the electron-withdrawing or electron-donating substituents of γ-glutamyl anilides. The reaction could be catalyzed by the general acid and carboxy of Asp-433 or phenolic hydroxyl Tyr-444 may be the acid by autodock simulation for all prepared γ-glutamyl anilides.