Enhanced carrier transport and visible light response in CA-β-CD/g-C3N4/Ag2O 2D/0D heterostructures functionalized with cyclodextrin for effective organic degradation

Xue Li,Tingting Liu,Fei Tian,Xiyang Tao,Zhansheng Wu 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.11

The high cost and low carrier separation efficiency of g-C3N4/Ag2O photocatalysts affect its application in the degradation of organic pollutants. In this study, the CA-βCD/g-C3N4/Ag2O 2D/0D heterojunction photocatalysts were successfully prepared to enhance the visible light response and inhibit the electron-hole recombination simultaneously during pollutant degradation. The 10:1:1 CA-βCD/g-C3N4/Ag2O showed the outstanding photochemical catalysis performance for the degradation of organic pollutants. The degradation efficiency of methyl orange, reactive black and norfloxacin was 2.53, 1.92 and 1.14 times than that of 1:1 g-C3N4/Ag2O. In addition, 10:1:1 CA-β-CD/g-C3N4/Ag2O also showed excellent photocatalytic stability. The free radical scavenging experiment and electron spin resonance proved that ·O − 2 was the chief active specie in the degradation process. The mechanism research results showed that the formation of heterojunction improved the utilization rate of sunlight and promoted the separation efficiency of photo-generated electrons and holes, which significantly advanced the photocatalytic activity of the composite catalyst. The preparation of CA-βCD/g-C3N4/Ag2O provided ideas for modification of photocatalyst by macromolecular organic matter.

Heterologous Expression of Rhizopus Oryzae CYP509C12 Gene in Rhizopus Nigricans Enhances Reactive Oxygen Species Production and 11α-Hydroxylation Rate of 16α, 17-Epoxyprogesterone

( Chaohui Shen ),( Xiyang Gao ),( Tao Li ),( Jun Zhang ),( Yuqian Gao ),( Liyou Qiu ),( Guang Zhang ) 한국균학회 2019 Mycobiology Vol.47 No.3

The 11a-hydroxylation of 16a, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The 11a-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the 11a-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The H₂O₂ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the 11a-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

Dynamics of fungal community during silage fermentation of elephant grass (Pennisetum purpureum) produced in northern Vietnam

Viet Ha Vu,Xiyang Li,Mengyuan Wang,Rongmei Liu,Guojian Zhang,Wei Liu,Baixue Xia,Qun Sun 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.7

Objective: This study aimed to gain deeper insights into the dynamic changes in spoilage fungi populations during fermentation and the influence of traditional additives on silage quality. Methods: Elephant grass (Pennisetum purpureum) was prepared without any additive (control), and with the addition of 0.5% salt, and 0.5% salt–0.2% sugar mixture. The fungal community was then determined using a classic culturing method and high-throughput sequencing at 0, 5, 15, and 60 days after ensiling. Results: The results showed that the fungal community of elephant grass silage varied significantly between the natural fermentation without any additive and the two additive groups. The diversity and relative abundance of spoilage molds in the control group were much higher than those in the two treatment groups (p<0.05). Three species of yeasts (Candida sp., Pichia sp., Trichosporon sp.) and four spoilage molds (Fusarium sp., Aspergillus sp., Muco sp. and Penicillin sp.) were the predominant fungi in elephant grass during natural fermentation from 0 to 60 days, which were found to be significantly decreased in salt and sugar additive groups (p<0.05). Meanwhile, the diversity and relative abundance of undesirable molds in the 0.5%-salt additive group were the lowest among all groups. Conclusion: Adding salt and sugar, particularly 0.5% salt, is a promising effective approach to reduce the amount of undesirable fungi thus, improving the silage quality of elephant grass in northern Vietnam.

Heterologous Expression of Rhizopus Oryzae CYP509C12 Gene in Rhizopus Nigricans Enhances Reactive Oxygen Species Production and 11α-Hydroxylation Rate of 16α, 17-Epoxyprogesterone

Shen, Chaohui,Gao, Xiyang,Li, Tao,Zhang, Jun,Gao, Yuqian,Qiu, Liyou,Zhang, Guang The Korean Society of Mycology 2019 Mycobiology Vol.47 No.3

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

Drying performance and energy consumption of Camellia oleifera seeds under microwave-vacuum drying

Dongyan Zhang,Dan Huang,Xiyang Zhang,Hangyi Zhao,Guiliang Gong,Xiaohong Tang,Lijun Li 한국식품과학회 2023 Food Science and Biotechnology Vol.32 No.7

Microwave-vacuum drying performance and energy consumption of Camellia oleifera seeds were studied in this paper. The effects of microwave power, vacuum pressure and loading quantity were evaluated and discussed. Orthogonal experiments were also conducted to optimize the drying process. A new drying model based on the weibull distribution model was developed. Results showed that the microwave-vacuum drying process was dominated by internal water diffusion and surface water evaporation. As the microwave power and vacuum pressure increased and the loading quantity decreased, the drying time and energy consumption both decreased. However, too low or too high microwave power would increase the energy consumption. The optimal microwave-vacuum drying conditions were found to be a loading quantity of 150 g, a microwave power of 350 W and a vacuum pressure of 0.09 MPa. The developed drying model and the calculated scale and shape parameter were all consistent with experimental results.

PCSK9 regulates myocardial ischemia–reperfusion injury through parkin/pink1-mediated autophagy pathway

Huang Guangwei,Bao Hailong,Zhan Peng,Lu Xiyang,Duan Zonggang,Xiong Xinlin,Lin Muzhi,Wang Bing,An Hongxin,Xiahou Luanda,Zhou Haiyan,Luo Zhenhua,Li Wei 대한독성 유전단백체 학회 2024 Molecular & cellular toxicology Vol.20 No.2

Objectives This study aimed at investigating the role of the proprotein convertase subtilisin/Kexin type 9 (PCSK9)-mediated autophagy on myocardial ischemia/reperfusion injury (MIRI). To determine the relationship between autophagy, apoptosis, fibrosis, and inflammation in the myocardium, to provide experience in preventing and treating the myocardial ischemia/reperfusion (I/R) injury. Methods An AC16 hypoxia-reoxygenation model and a rat myocardial ischemia–reperfusion model were established. The concentrations of cardiac troponin T (cTnT) and creatine kinase-MB (CKMB) in plasma were measured by ELISA. To determine the size of the myocardial infarction, TTC/EB staining was performed. In addition to identifying pathological changes in myocardial tissue, Masson’s trichrome stains and H&E stains were used to identify pathological changes. Echocardiography was employed to detect cardiac function. Western blot analysis was then performed to detect the protein expression of Parkin, Pink1, and markers associated with autophagy (Beclin-1, p62, LC3). Results A significant increase in PCSK9 was observed in the myocardium during H/R. In the cardiac-specific PCSK9 knockdown model, cardiac autophagy was significantly inhibited, whereas cardiac-specific PCSK9 overexpression promoted cardiac autophagy. In vivo studies have demonstrated a significant decrease in cardiac autophagy when the PCSK9 inhibitor was administered. Apoptosis induced by I/R was greatly decreased, and myocardial infarction size and function were both improved by PCSK9 inhibitors. Mechanistically, the PCSK9 inhibitor improved the degree of myocardial fibrosis and inhibited the development of inflammation. Conclusions Our results demonstrated that increased PCSK9 via the parkin/pink1 signaling pathway contributes to I/R and H/R by exaggerating excessive autophagy during reperfusion/reoxygenation. In addition, the PCSK9 inhibitor blocked the development of inflammation and improved Infarct size, myocardial function, and myocardial fibrosis.