Erythritol production by Yarrowia lipolytica mutant strain M53 generated through atmospheric and room temperature plasma mutagenesis

Xiaoyan Liu,Jinshun Lv,Jiaxing Xu,Jun Xia,Benlin Dai,Xiangqian Xu,Jiming Xu 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.4

Mutants of Yarrowia lipolytica with high erythritol production were generated through an atmospheric and room temperature plasma (ARTP) mutation system. Among these mutants, Y. lipolytica M53 exhibited the highest erythritol yield. In a batch culture, M53 produced 64.8 g/L erythritol from 100 g/L glycerol. The yields of byproducts (e.g. mannitol, arabitol, and a-ketoglutaric acid) were low, and the mechanisms underlying these changes were examined by measuring enzyme activities in the pentose phosphate pathway. Up to 145.2 g/L erythritol was produced by M53 from 200 g/L of glycerol, and erythritol accumulation was promoted by 3.7 mg/L of Cu2?, 10.15 mg/L of Mn2?, and 30.37 g/L of NaCl. Fed-batch cultivation of M53 in a 5-L fermentor produced 169.3 g/L erythritol with low levels of byproducts within 168 h. This finding confirmed the potential of M53 as an erythritol producer on a commercial scale.

Enhanced luminescence of Tb3+ by efficient energy transfer from Ce3+ in Sr2B5O9Cl host

Jiming Zheng,Chongfeng Guo,Xu Ding,Zhaoyu Ren,Jintao Bai 한국물리학회 2012 Current Applied Physics Vol.12 No.3

Ce3+ and Tb3+ co-doped Sr2B5O9Cl phosphors with intense green emission were prepared by the conventional high-temperature solid-state reaction technique. A broad band centered at about 315 nm was found in phosphor Sr2B5O9Cl: Ce3+, Tb3+ excitation spectrum, which was attributed to the 4f-5d transition of Ce3+. The typical sharp line emissions ranging from 450 to 650 nm were originated from the 5D4/7FJ (J ¼ 6, 5, 4, 3) transitions of Tb3+ ions. The photoluminescence (PL) intensity of green emission from Tb3+ was enhanced remarkably by co-doping Ce3+ in the Tb3+ solely doped Sr2B5O9Cl phosphor because of the dipoleedipole mechanism resonant energy transfer from Ce3+ to Tb3+ ions. The energy transfer process was investigated in detail. In light of the energy transfer principles, the optimal composition of phosphor with the maximum green light output was established to be Sr1.64Ce0.08Tb0.1Li0.18B5O9Cl by the appropriate adjustment of dopant concentrations. The PL intensity of Tb3+ in the phosphor was enhanced about 40 times than that of the Tb3+ single doped phosphor under the excitation of their optimal excitation wavelengths.

Assessment of across-wind responses for aerodynamic optimization of tall buildings

Xu, Zhendong,Xie, Jiming Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.21 No.5

A general approach of aerodynamic optimization of tall buildings is presented in this paper, focusing on how to best compromise wind issues with other design aspects in the most efficient manner. The given approach is reinforced by establishing an empirical method that can quickly assess the across-wind loads and accelerations as a function of building frequencies, building dimensions, aspect ratios, depth-to-width ratios, and site exposures. Effects of corner modifications, including chamfered corner and recessed corner, can also be assessed in early design stages. Further, to assess the effectiveness of optimization by tapering, stepping or twisting building elevations, the authors introduce a method that takes use of sectional aerodynamic data derived from a simple wind tunnel pressure testing to estimate reductions on overall wind loads and accelerations for various optimization options, including tapering, stepping, twisting and/or their combinations. The advantage of the method is to considerably reduce the amount of wind tunnel testing efforts and speed up the process in finding the optimized building configurations.

Assessment of across-wind responses for aerodynamic optimization of tall buildings

Zhendong Xu,Jiming Xie 한국풍공학회 2015 Wind and Structures, An International Journal (WAS Vol.21 No.5

A general approach of aerodynamic optimization of tall buildings is presented in this paper, focusing on how to best compromise wind issues with other design aspects in the most efficient manner. The given approach is reinforced by establishing an empirical method that can quickly assess the across-wind loads and accelerations as a function of building frequencies, building dimensions, aspect ratios, depth-to-width ratios, and site exposures. Effects of corner modifications, including chamfered corner and recessed corner, can also be assessed in early design stages. Further, to assess the effectiveness of optimization by tapering, stepping or twisting building elevations, the authors introduce a method that takes use of sectional aerodynamic data derived from a simple wind tunnel pressure testing to estimate reductions on overall wind loads and accelerations for various optimization options, including tapering, stepping, twisting and/or their combinations. The advantage of the method is to considerably reduce the amount of wind tunnel testing efforts and speed up the process in finding the optimized building configurations.

Effect of Bacterial Wilt on Fungal Community Composition in Rhizosphere Soil of Tobaccos in Tropical Yunnan

Yuanxian Zheng,Jiming Wang,Wenlong Zhao,Xianjie Cai,Yinlian Xu,Xiaolong Chen,Min Yang,Feiyan Huang,Lei Yu,Yuansheng He 한국식물병리학회 2022 Plant Pathology Journal Vol.38 No.3

Bacterial wilt, which is a major soil-borne disease with widespread occurrence, poses a severe danger in the field of tobacco production. However, there is very limited knowledge on bacterial wilt-induced microecological changes in the tobacco root system and on the interaction between Ralstonia solanacearum and fungal communities in the rhizosphere soil. Thus, in this study, changes in fungal communities in the rhizosphere soil of tobaccos with bacterial wilt were studied by 18S rRNA gene sequencing. The community composition of fungi in bacterial wilt-infected soil and healthy soil in two tobacco areas (Gengma and Boshang, Lincang City, Yunnan Province, China) was studied through the paired comparison method in July 2019. The results showed that there were significant differences in fungal community composition between the rhizosphere soil of diseased plants and healthy plants. The changes in the composition and diversity of fungal communities in the rhizosphere soil of tobaccos are vital characteristics of tobaccos with bacterial wilt, and the imbalance in the rhizosphere microecosystem of tobacco plants may further aggravate the disease.

Low-dose of organic trace minerals reduced fecal mineral excretion without compromising performance of laying hens

Qiu, Jialing,Lu, Xintao,Ma, Lianxiang,Hou, Chuanchuan,He, Junna,Liu, Bing,Yu, Dongyou,Lin, Gang,Xu, Jiming Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.4

Objective: The objective of this study was to investigate the effects of low doses of organic trace minerals (iron, copper, manganese, and zinc) on productive performance, egg quality, yolk and tissue mineral retention, and fecal mineral excretion of laying hens during the late laying period. Methods: A total of 405 healthy hens (HY-Line White, 50-week-old) were randomly divided into 3 treatments, with 9 replicates per treatment and 15 birds per replicate. The dietary treatments included feeding a basal diet + inorganic trace minerals at commercial levels (CON), a basal diet + inorganic trace minerals at 1/3 commercial levels (ITM), and a basal diet + proteinated trace minerals at 1/3 commercial levels (TRT). The trial lasted for 56 days. Results: Compared to CON, ITM decreased (p<0.05) egg production, daily egg mass, albumen height, eggshell strength, yolk Fe concentration, serum alkaline phosphatase activity and total protein, and increased (p<0.05) egg loss and feed to egg ratio. Whereas with productive performance, egg quality, yolk mineral retention, and serum indices there were no differences (p>0.05) between CON and TRT. The concentrations of Fe and Mn in the tissue and tibia were changed notably in ITM relative to CON and TRT. Both ITM and TRT reduced (p<0.05) fecal mineral excretion compared to CON. Conclusion: These results indicate that dietary supplementation of low-dose organic trace minerals reduced fecal mineral excretion without negatively impacting hen performance and egg quality.