Improvement of Fumigaclavine C Production in a Two-stage Culture of Aspergillus fumigatus with Molasses as a Cost-effective Ingredient

Yi-Xiang Zhu,WEIWEI HUAN,Ling-yun Yao,Wan-Guo Yu,Ruihua Jiao,Yan-Hua Lu,Renxiang Tan 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.6

Fumigaclavine C (FC), which is produced by Aspergillus fumigatus, is a conidiation-associated ergot alkaloid with significant medical benefits. However, its application is restricted by low yields from submerged cultures. In this study, the technical feasibility of using molasses as a cost-effective ingredient for FC production in a two-stage culture of A. fumigatus was evaluated. The results indicated that molasses supplementation significantly enhanced FC accumulation by promoting conidiation and up-regulating hydroxymethylglutaryl-CoA reductase activity. Via the optimization of the two-stage process in the presence of molasses, FC production in shake flasks reached 226.9 mg/L, which was approximately three times that in the original medium (75.9 mg/L). The use of molasses as a cost-effective ingredient for FC fermentation was also successfully reproduced in a lab-scale bioreactor system in which the maximum FC production reached 215.0 mg/L. The FC production obtained in this study is the highest ever reported. This increased efficiency will enable large-scale production of FC and extend the application of molasses as a low-cost substrate for producing other conidiation-related secondary metabolites.

Density measurement and equal density temperature of CO2+brine from Dagang - formation from 313 to 363 K

Yi Zhang,Weiwei Jian,Yangchun Zhan,Yongchen Song,Mingjun Yang,Jiafei Zhao,Yu Liu,Weiguo Liu,Yong Shen 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.1

Densities of CO2+Dagang - formation brine solution were measured by a magnetic suspension balance(MSB) in the pressure range from (10 to 18) MPa, at the temperatures from (313.15 to 363.15) K and CO2 mass frac-tions at 0, 0.0101, 0.0198 and 0.0299. The experimental results revealed that the solution densities increased linearlywith the increasing pressure and CO2 concentration, while decreasing with the increasing temperatures in the experi-mental range. When the temperature increased from (313.15 to 363.15) K, the slopes of the densities versus (vs.) CO2mass fractions decreased from (0.193 to 0.106) g·cm−3. A correlation equation was developed based on thermody-namic theory and experimental data. The absolute average deviation between the correlation equation and the experi-mental data was 0.05%, and the maximum deviation was 0.37% for the density of CO2+water/brine solution in com-mon geological storage conditions. According to the density of CO2 - free brine and apparent molar volume of CO2 inbrine, the equal density temperature (Te) of CO2+Dagang brine solution was obtained at 464.67 K when pressure is10MPa, which means that the density of brine dissolved with CO2 will be less than that of CO2-free brine when thetemperature is higher than 464.67 K at 10MPa. In this work the formation temperature of the Dagang oilfield reser-voir is from 313.15 K to 363.15 K, which is lower than the equal density temperature. Therefore, the safety of CO2 stor-age in Dagang oilfield reservoir can be guaranteed.

Maize-Straw-Derived Biochar Effectively Suppressed the Decomposition of Native Organic Carbon in an Intensively Cultivated Sandy Loam Soil of North China Plain: A Negative Priming Effect

Weiwei Lu,Weixin Ding,Junhua Zhang,Yi Li,Jiafa Luo,Nanthi Bolan,Zubin Xie 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Involvement of Nuclear Related Factor 2 Signaling Pathway in the Brain of Obese Rats and Obesity-Resistant Rats Induced by High-Fat Diet

Weiwei Ma,Bingjie Ding,Li-Jing Wang,Yi Shao,Rong Xiao 한국식품영양과학회 2016 Journal of medicinal food Vol.19 No.4

We aimed to investigate the mechanism of brain damage in diet-induced obese (DIO) rats and diet-resistant (DR) rats from the viewpoint of redox state and nuclear related factor 2 (Nrf2) signaling pathway. Sprague-Dawley rats were fed with a high-fat diet for 10 weeks to obtain the DIO and DR rats. d-Galactose was injected subcutaneously through the back of the neck for 10 weeks to establish oxidative stress model rats. Then, the ratio of reduced glutathione (GSH)/oxidized glutathione (GSSG) and the level of glutathione peroxidase (GSH-Px) in serum and brain tissue were measured by using enzymatic assay kits. The levels of cholecystokinin and peptide YY in the brain tissue were detected by using enzyme-linked immunosorbent assay kits. In addition, the protein expression of Nrf2 and its downstream factors such as heme oxygenase 1, manganese superoxide dismutase, and NAD(P)H quinone oxidoreductase 1 (NQO1) in the brain tissue were measured by Western blotting. In the brain of DIO rats, the level of GSH and ratio of GSH/GSSG were lower, whereas the GSH-Px concentration was higher compared with DR rats significantly. On the other hand, the GSSG level was higher in the serum of DIO rats compared with the DR rats. The oxidative stress state in the brain of DIO rats, but not in DR rats, were observed. In addition, the protein expressions of Nrf2 and NQO1 were downregulated in the brain of DR rats compared with that in DIO rats. Our data suggest that the Nrf2/NQO1 signaling pathway and redox state were involved in the pathogenesis of the rats prone to obesity, but not the DR rats resistant to obesity.

3D Architectures of LaVO₄:Eu³⁺ Microcrystals via an EG-assisted Hydrothermal Method: Phase Selective Synthesis, Growth Mechanism and Luminescent Properties

Ding, Yi,Zhang, Bo,Ren, Qifang,Zhang, Qicai,Zha, Weiwei,Li, Xin,Chen, Shaohua,Oh, Won-Chun The Korean Ceramic Society 2017 한국세라믹학회지 Vol.54 No.2

In this article, pure $m-LaVO_4:Eu^{3+}$ and $t-LaVO_4:Eu^{3+}$ nanocrystals were prepared by an EG-assisted hydrothermal method with regular shapes. A series of controlled experiments showed that the pH value of a mixed solution, the volume ratio of $EG/H_2O$ and the dosage of the doped $Eu^{3+}$ all had an important effect on the sizes and shapes of the final products. Furthermore, the constitutional unit of the products changed from 0D to 2D with an increase in the EG dosage. The PL results showed that $t-LaVO_4$ doped with $Eu^{3+}$ ions had better luminescence properties than $m-LaVO_4$ due to its special structure. All of these results not only expand our understanding of the luminescence properties of lanthanide orthovanadates, but they also elucidate the principles of the crystal growth.

한국어와 중국어의 수(數) 표현에 대한 대조 연구

( Li Weiwei ),이선웅 ( Yi Seon-ung ) 한민족어문학회 2018 韓民族語文學 Vol.0 No.80

본고는 대조언어학의 관점에서 한·중 수 표현 대조를 통해 정수 표현, 서수 표현, 개략수 표현에 어떤 공통점과 차이점이 있는지를 살펴볼 것이다. 수 표현은 수사에 의해 표현되는 수량 범주이다. 대부분의 선행 연구는 수사와 수 표현을 구분하지 않고 모두 수사 체계에 포함시켰는데 본고는 수사와 수 표현을 구분하는 입장에서 수사 체계와 수 표현 체계를 나누어 고찰하였다. 수사의 구성에 주목하여 수사 체계를 구축하였고 수사를 사용하여 특정한 수량 범주를 표현하는 것을 수 표현으로 분류하여 수 표현 체계를 구축하였다. 한·중의 수 표현 체계에는 정수 표현, 서수 표현, 개략수 표현을 포함한 다. 각 범주에서 한·중의 표현 양상을 자세히 살펴보았다. 한·중의 정수 표현에서는 중국어에는 보조수사 ‘零(0), 兩(2)’이 있는 등 한국어와 다소간 차이점을 보였다. 서수 표현에 있어서는 ‘수사+명사’의 방법으로 양수와 서수를 모두 나타낼 수 있음을 한국어와 중국어에서 모두 확인하였다. 개략수 표현에 있어서는 한국어보다 중국어의 개략수 표현 방법이 더 다양하다. 본고는 표현론적 관점에서 한·중의 수 표현의 공통점과 차이점을 추출하여 중국인 학습자에 대한 한국어 교육에도 충실한 자료가 될 것이라 생각한다. The purpose of this paper is to contrast the numerical expressions used in the Korean and Chinese numeral systems. The numerical expression in this paper is the quantity category expressed by the numerals. In the previous study, numerals and numerical expressions were both included in the numeral system. We constructed a microscopic numeral system of Korean and Chinese numbers by paying attention to the constitution principle of the numerals. We also constructed a numerical expression system for Korean and Chinese numbers by expressing quantities using macroscopic numerals. The system includes basic numerals, unit numerals, and union numerals from the Korean numeral system, and basic numerals, unit numerals, auxiliary numerals, and union numerals from the Chinese numeral system. Korean and Chinese numerical expressions include integer expressions, ordinal expressions, and approximate numerical expressions. In this paper, the integer expressions, the ordinal expressions, and the approximate expressions used in the Korean and Chinese numerical expression systems are compared; the differences and common points between the expressions in each category are revealed.

Vision measurement of gear pitting based on DCGAN and U-Net

Zhiwen Wang,Yi Qin,Weiwei Chen 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.7

To quantitatively detect the gear pitting, this paper proposes a vision measurement method based on deep convolutional generative adversarial network (DCGAN) and fully convolutional segmentation network (U-Net) for measuring the area ratio of gear pitting. A machine vision system is designed to automatically collect the pitting images of all gear teeth obtained from gear fatigue tests, but the pitting images are not sufficient due to the high cost of gear fatigue test. To solve the problem of small sample, DCGAN is applied to expand pitting samples. By the expansive sample set, the edge detection algorithm and U-Net are respectively used to segment the tooth surface and pitting. The proposed approach is applied to measure the gear pitting, and a comprehensive evaluation index is designed to evaluate the performance of gear pitting detection. Experimental results show that the average relative error and the absolute error of pitting area ratio obtained by the proposed method are respectively 7.83 % and 0.18 %, which are much lower than those obtained by the conventional detection method without sample augmentation. Thus, the proposed method has satisfactory accuracy and precede the detection method without sample augmentation.

Neferine increase in vitro anticancer effect of dehydroepiandrosterone on MCF-7 human breast cancer cells

Yang, Dingyi,Zou, Xiaochuan,Yi, Ruokun,Liu, Weiwei,Peng, Deguang,Zhao, Xin The Korean Society for Applied Biological Chemistr 2016 Applied Biological Chemistry (Appl Biol Chem) Vol.59 No.4

This study was conducted to investigate the in vitro anticancer reinforcing effects of neferine (Nef) on dehydroepiandrosterone (DHEA) and the mechanism was also determined during the investigation. By the growth effects of Nef and DHEA on MCF-7 human breast cancer cells, 8 mg/mL Nef was a non-virulent concentration in MCF-7 cells, and this concentration was used for further experiment. In 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide assay, 30 mg/mL DHEA showed 49.4 % growth inhibitory effect in MCF-7 cells, whereas Nef (8 mg/mL) + DHEA (30 mg/mL) treatment had the higher effect at 67.8 %. The flow cytometry analysis results showed that 15 and 30 mg/mL DHEA-treated MCF-7 cells had 12.2 and 21.6 % apoptotic cells, respectively, Nef + DHEA could raise the apoptotic cells to 36.7 %. Reverse transcription-polymerase chain reaction assay shows remarkable results according to which DHEA could significantly increase caspase-3, caspase-8, caspase-9, Bax, p53, p21, E2F1, Fas, FasL mRNA expressions and decrease Bcl-2, Bcl-xL, HIAP-1, HIAP-2, survivin expressions as compared to the untreated control cancer cells. Moreover, these effects depend on the concentration of DHEA, and Nef which could further strengthen these effects. From these results, low concentration of Nef could not influence the growth of MCF-7 cells, but using its sensitization effect, Nef raised the in vitro effects of DHEA. Nef could be got easily. With these results we can accomplish that Nef + DHEA might be used as the new anticancer materials combination.

Neferine increase in vitro anticancer effect of dehydroepiandrosterone on MCF-7 human breast cancer cells

Dingyi Yang,Xiaochuan Zou,Ruokun Yi,Weiwei Liu,Deguang Peng,Xin Zhao 한국응용생명화학회 2016 Applied Biological Chemistry (Appl Biol Chem) Vol.59 No.4

This study was conducted to investigate the in vitro anticancer reinforcing effects of neferine (Nef) on dehydroepiandrosterone (DHEA) and the mechanism was also determined during the investigation. By the growth effects of Nef and DHEA on MCF-7 human breast cancer cells, 8 mg/mL Nef was a non-virulent concentration in MCF-7 cells, and this concentration was used for further experiment. In 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide assay, 30 mg/mL DHEA showed 49.4 % growth inhibitory effect in MCF-7 cells, whereas Nef (8 mg/mL) + DHEA (30 mg/mL) treatment had the higher effect at 67.8 %. The flow cytometry analysis results showed that 15 and 30 mg/mL DHEA-treated MCF-7 cells had 12.2 and 21.6 % apoptotic cells, respectively, Nef + DHEA could raise the apoptotic cells to 36.7 %. Reverse transcription-polymerase chain reaction assay shows remarkable results according to which DHEA could significantly increase caspase-3, caspase-8, caspase-9, Bax, p53, p21, E2F1, Fas, FasL mRNA expressions and decrease Bcl-2, Bcl-xL, HIAP-1, HIAP-2, survivin expressions as compared to the untreated control cancer cells. Moreover, these effects depend on the concentration of DHEA, and Nef which could further strengthen these effects. From these results, low concentration of Nef could not influence the growth of MCF-7 cells, but using its sensitization effect, Nef raised the in vitro effects of DHEA. Nef could be got easily. With these results we can accomplish that Nef + DHEA might be used as the new anticancer materials combination.

Fabrication of copper ions-substituted hydroxyapatite/polydopamine nanocomposites with high antibacterial and angiogenesis effects for promoting infected wound healing

Bailong Tao,Chuanchuan Lin,Ai Guo,Yonglin Yu,Xian Qin,Kai Li,Hongchuan Tian,Weiwei Yi,Dengliang Lei,Lixue Chen 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.104 No.-

Infected wound healing remains a critical threat, which frequently delays the healing process and evenleads to severe life-threatening complications. Herein, we reported an effective anti-infection approach,which was based on copper ions-releasing hydroxyapatite/polydopamine (HA-Cu/PDA) nanocompositeswith photothermal effect. The HA-Cu/PDA nanocomposites was fabricated through a co-precipitationreaction between polydopamine (PDA)-coated hydroxyapatite nanoparticles (HA)-loaded Cu2+ (HA-Cu). Through a synergistic effect of released Cu2+ and photothermal efficiency of PDA coating, and the HACu/PDA nanocomposites exhibited extraordinary antibacterial capacities against Escherichia coli (E. coli)and Staphylococcus aureus (S. aureus). The nanocomposites presented good biocompatibility for mouseembryonic fibroblast (NIH-3T3) cells and promoted NIH3T3 cells to migrate toward wound sites. Additionally, this nanocomposite could stimulate the tissue remodeling-related gene expression toinduce the blood vessels formation, granulation tissues and collagen deposition, and eventually enhancewound healing. In vivo study further verified that HA-Cu/PDA nanocomposites with NIR irradiation couldsignificantly improve bacterial infected wound healing through the prominent antibacterial property,reduced inflammatory response, the formation of granulation tissue, collagen deposition, and angiogenesisability. Thus, this study develops a versatile strategy for a broad range of wound healing and skinreconstruction caused by bacterial infection.