Diversity of Butyrivibrio Group Bacteria in the Rumen of Goats and Its Response to the Supplementation of Garlic Oil

Zhu, Zhi,Hang, Suqin,Mao, Shengyong,Zhu, Weiyun Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.2

This study aimed to investigate the diversity of the Butyrivibrio group bacteria in goat rumen and its response to garlic oil (GO) supplementation as revealed by molecular analysis of cloned 16S rRNA genes. Six wethers fitted with ruminal fistulas were assigned to two groups for a cross-over design with 28-d experimental period and 14-d interval. Goats were fed a basal diet without (control) or with GO ruminal infusion (0.8 g/d). Ruminal contents were used for DNA extraction collected before morning feeding on d 28. A total bacterial clone library was firstly constructed by nearly full-length 16S rRNA gene cloned sequences using universal primers. The resulting plasmids selected by Butyrivibrio-specific primers were used to construct a Butyrivibrio group-specific bacterial clone library. Butyrivibrio group represented 12.98% and 10.95% of total bacteria in control and GO group, respectively. In libraries, clones were classified to the genus Pseudobutyrivibrio, Butyrivibrio and others within the family Lachnospiraceae. Additionally, some specific clones were observed in GO group, being classified to the genus Ruminococcus and others within the family Ruminococcaceae. Based on the criterion that the similarity was 97% or greater with database sequences, there were 29.73% and 18.42% of clones identified as known isolates (i.e. B. proteoclasticus and Ps. ruminis) in control and GO groups, respectively. Further clones identified as B. fibrisolvens (5.41%) and R. flavefaciens (7.89%) were specifically found in control and GO groups, respectively. The majority of clones resembled Ps. ruminis (98% to 99% similarity), except for Lachnospiraceae bacteria (87% to 92% similarity) in the two libraries. The two clone libraries also appeared different in Shannon diversity index (control 2.47 and GO group 2.91). Our results indicated that the Butyrivibrio group bacteria had a complex community with considerable unknown species in the goat rumen.

Effect of Rapid Chilling on Beef Quality and Cytoskeletal Protein Degradation in M. longissimus of Chinese Yellow Crossbred Bulls

Mao, Yanwei,Zhang, Yimin,Liang, Rongrong,Ren, Lulu,Zhu, He,Li, Ke,Zhu, Lixian,Luo, Xin Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.8

The objective of this study was to investigate the effect of rapid chilling (RC) on beef quality and the degradation of cytoskeletal proteins. Twenty Chinese Yellow crossbred bulls were selected and randomly divided into two groups. RC and conventional chilling (CC) were applied to left and right sides of the carcasses respectively after slaughtering. To determine whether electrical stimulation (ES) treatment can alleviate the potential hazard of RC on meat quality, ES was applied to one group. The effects of RC and ES were determined by meat color, shear force and cytoskeletal protein degradation postmortem (PM). The results showed that RC decreased beef tenderness at 1 d and 3 d postmortem, but had no detrimental effect on meat color. Western blotting showed that RC decreased the degradation rate of desmin and troponin-T, but the effects weakened gradually as postmortem aging extended. Degradation rates of both desmin and troponin-T were accelerated by ES. The combination of RC and ES could improve beef color, accelerate degradation rate of cytoskeletal protein and improve beef tenderness.

Effects of Ruminal Infusion of Garlic Oil on Fermentation Dynamics, Fatty Acid Profile and Abundance of Bacteria Involved in Biohydrogenation in Rumen of Goats

Zhu, Zhi,Mao, Shengyong,Zhu, Weiyun Asian Australasian Association of Animal Productio 2012 Animal Bioscience Vol.25 No.7

This study aimed to investigate the effects of ruminal infusion of garlic oil (GO) on fermentation dynamics, fatty acid (FA) profile, and abundance of bacteria involved in biohydrogenation in the rumen. Six wethers fitted with ruminal fistula were assigned to two groups for cross-over design with a 14-d interval. Each 30-d experimental period consisted of a 27-d adaptation and a 3-d sample collection. Goats were fed a basal diet without (control) or with GO ruminal infusion (0.8 g/d). Ruminal contents collected before (0 h) and at 2, 4, 6, 8, and 10 h after morning feeding were used for fermentation analysis, and 0 h samples were further used for FA determination and DNA extraction. Garlic oil had no influence on dry matter intakes of concentrate and hay. During ruminal fermentation, GO had no effects on total VFA concentration and individual VFA molar proportions, whereas GO increased the concentrations of ammonia nitrogen and microbial crude protein (p<0.05). Compared with control, GO group took a longer time for total VFA concentration and propionate molar proportion to reach their respective maxima after morning feeding. The ratio of acetate to propionate in control reduced sharply after morning feeding, whereas it remained relatively stable in GO group. Fatty acid analysis showed that GO reduced saturated FA proportion (p<0.05), while increasing the proportions of C18, t11-18:1 (TVA), c9,t11-conjugated linoleic acid (c9,t11-CLA), t10,c12-CLA, and polyunsaturated FA (p<0.05). The values of TVA/(c9,t11-CLA+TVA) and C18:0/(TVA+C18:0) were reduced by GO (p<0.05). Real-time PCR showed that GO tended to reduce Butyrivibrio proteoclasticus abundance (p = 0.058), whereas GO had no effect on total abundance of the Butyrivibrio group bacteria. A low correlation was found between B. proteoclasticus abundance and C18:0/(TVA+C18:0) (p = 0.910). The changes of fermentation over time suggested a role of GO in delaying the fermentation process and maintaining a relatively modest change of ruminal environment. The inhibitory effects of GO on the final step of biohydrogenation may be related to its antibacterial activity against B. proteoclasticus and other unknown bacteria involved.

Predictive Value of the Surface-Enhanced Resonance Raman Scattering-Based MTT Assay: A Rapid and Ultrasensitive Method for Cell Viability in Situ

Mao, Zhu,Liu, Zhuo,Chen, Lei,Yang, Jin,Zhao, Bing,Jung, Young Mee,Wang, Xu,Zhao, Chun American Chemical Society 2013 ANALYTICAL CHEMISTRY - Vol.85 No.15

<P>SERRS (surface-enhanced resonance Raman scattering) has been used to develop and optimize a novel and quantitative MTT assay for living cell viability. This highly sensitive method derives from two factors for formazan signal enhancing: the addition of Au nanoparticles and the resonance effect by 632.8 nm of excitation. The results show that the background elements, such as excessive MTT residues, serum, and the drug, did not interfere with the detection of formazan. Moreover, the detection limit of formazan is as low as 1 ng/mL. With the use of this method to quantify metabolically viable cells, dose–response curves of treated and untreated cells with the drug were constructed on the human lung cancer cell A549. The results also show that the Raman signal generated is dependent on the degree of activation of the cells. In comparison to the traditional method, the main advantages of this method are its rapidity (30 min), high-selectivity, high-precision, and cost-effectiveness (0.1 mg/mL MTT) without time-consuming steps and any modifying or labeling procedure. This work reports on an improved research tool that may help researchers apply this method for in situ cell assays.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancham/2013/ancham.2013.85.issue-15/ac401254s/production/images/medium/ac-2013-01254s_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ac401254s'>ACS Electronic Supporting Info</A></P>

Label-Free SERS Selective Detection of β-Lactamases Using Solid Phase Microextraction

( Zhu Mao ),( Mengyu Jing ),정영미 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

β-lactamase is an important bacterial enzyme with the ability to efficiently cleave β-lactam antibiotics. Therefore, there are reports of unscrupulous manufacturers illegally adding β-lactamase into milk to hide antibiotic residues. It is important to develop a reliable and highly sensitive on-site and real-time detection of β-lactamase in dairy products. Surface-enhanced Raman spectroscopy (SERS) is a highly sensitive, fingerprint-based, fast analysis technique. We combined solid phase microextraction (SPME) and SERS technique to develop a rapid and highly sensitive detection method for β-lactamase in dairy products. In this work, Ag-loaded TiO2 nanotube arrays fiber exhibited remarkable SERS activity and SPME selectivity. The results were shown that β-lactamase in milk solution at a low concentration of 0.5U/L can be easily detected without any pretreatment.

Plastic depth and load-bearing capacity of autofrettaged cylinders

Ruilin Zhu,Guolin Zhu,Aifeng Mao 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.6

Autofrettage technology is usually adopted to even out and reduce stresses as well as improve the load-bearing capacity of a variety of cylindrical ultra-high mechanical apparatuses. The autofrettage of cylinders is theoretically investigated based on maximum shear stress theory or the Tresca criterion to establish the general law for autofrettage theory. The equation for the optimum plastic depth for a certain load and radius ratio is derived to ensure that the equivalent stress of the total stress does not exceed the yield limit and the absolute value of the equivalent stress of the residual stress at the internal surface likewise does not exceed the yield limit. Through this equation, a set of concise equations for total stress and residual stresses are obtained. The safe and optimum load-bearing conditions for cylinders are presented. Results show that, provided the pressure contained in a cylinder is equal to the autofrettage pressure, irrespective of k j , the equivalent total stress, s e , equals the yield limit everywhere in the entire plastic zone, that is, s e is a constant. In the elastic zone, s e is always lower than the yield limit, but if k j is outside the quasi-infinite area enclosed by the curves of the sense and possible plastic depth, then either compressive yield occurs or k j is meaningless. The results based on the Mises criterion and Tresca criteria are compared.

Projected changes in wind erosion climatic erosivity over high mountain Asia: results from dynamical downscaling outputs

Mao Rui,Xu Yuanyuan,Zhu Jianze,Zhang Xuezhen,Song Shuaifeng,Gong Dao-Yi,Liu Lianyou,Shi Peijun 한국기상학회 2024 Asia-Pacific Journal of Atmospheric Sciences Vol.60 No.4

Wind erosion climatic erosivity is a measure of climatic conditions that affect wind erosion. Projecting wind erosion climatic erosivity is curcial for predicting future wind erosion risk. In this study, we employed dynamic downscaling outputs from the MPI-ESM1-2-HR model to project changes in wind erosion climatic erosivity over High Mountain Asia (HMA) from 2041 to 2060 under a middle-emission scenario (an additional radiative forcing of 4.5 W/m2 by 2100). From 1995 to 2014, wind erosion climatic erosivity in HMA was high in the southwest, on the Qiangtang Plateau, and in the Qaidam Basin, exceeding 1 kg·m−1 s− 1. Compared to the period 1995–2014, wind erosion climatic erosivity is projected to decrease by 0.5 kg·m−1 s− 1 over the east of the Qiangtang Plateau and increase by approximately 1 kg·m−1 s− 1 in the southwest of the HMA during 2041–2060 under the middle emission scenario. This increase in wind erosion climatic erosivity in the southwest of HMA is attributed to a projected rise in high-wind frequency for 2041–2060 compared to 1995–2014. Conversely, the decrease in wind erosion climatic erosivity in the east of the Qiangtang Plateau results from increased precipitation during 2041–2060, which mitigates the effects of increased high-wind frequencies. Given the growing risk of wind erosion in the southwest of the HMA, it’s essential to implement appropriate mitigation policies for the future.

Identification of ssDNA Aptamers Specific for Anti-neuroexcitation Peptide III and Molecular Modeling Studies: Insights into Structural Interactions

Zhu, Jon,Wang, Jian,Su, Zhen-Cheng,Li, Qin,Cheng, Mao-Sheng,Zhang, Jing-Hai 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.9

Twelve ssDNA aptamers specific for a novel recombinant anti-neuroexcitation peptide (ANEPIII) were identified using the SELEX method from a 79-nucleotide ssDNA pool to purify ANEPIII in a more efficient way. To further understand the binding modes between ssDNA and ANEPIII, fully flexible dinucleotides were docked onto the homology-modeled ANEPIII structure. AutoDocking identified favorable binding sites on ANEPIII for nucleotides, which was valuable for designing more potent ligands.

pH-Based immunoassay: explosive generation of hydrogen ions through an immuno-triggered nucleic acid exponential amplification reaction

Mao, Dongsheng,Chen, Tianshu,Chen, Huinan,Zhou, Mengru,Zhai, Xingwei,Chen, Guifang,Zhu, Xiaoli The Royal Society of Chemistry 2019 The Analyst Vol.144 No.13

<P>In this work, we propose a novel concept and a proof-of-concept strategy for the fabrication of a pH-based immunoassay platform with a certain degree of universality and scalability to make it adaptable for different application scenarios. The immunoreactions for the target detection are converted to pH changes through an engineered and optimized isothermal nucleic acid amplification, named exponential amplification reaction (EXPAR). Thus, a variety of well-developed methods for pH analysis, <I>e.g.</I> pH indicators, pH-strips and pH meters, can be applied for immunoassay directly. Here, we show that this proof-of-concept strategy is applicable for both macromolecular and micromolecular antigens by adopting human platelet-derived growth factor-BB (PDGF-BB) and chloramphenicol (CAP) as the model targets, respectively. The detection can be achieved using a colorimetric pH indicator after a 15 min reaction of the immuno-triggered isothermal nucleic acid amplification. In addition, compared with the traditional enzyme-linked immunosorbent assay (ELISA), the performance of our strategy, especially the detection limits, is improved to varying degrees for different targets, making the strategy a promising alternative for diverse application scenarios of immunoassay.</P>

Active control of amplitude and phase of high-power RF systems in EAST ICRF heating experiments

Zhu Guanghui,Liu Lunan,Mao Yuzhou,Zhang Xinjun,Guo Yaoyao,Ai Lin,Jiang Runhao,Qin Chengming,Zhang Wei,Yang Hua,Yuan Shuai,Wang Lei,Ju Songqing,Wang Yongsheng,Sun Xuan,Yang Zhida,Wang Jinxin,Cheng Yan 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.2

The EAST ICRF system operating space has been extended in power and phase control with a low-level RF system for the new double-strap antenna. Then the multi-step power and periodic phase scanning experiment were conducted in L-mode plasma, respectively. In the power scanning experiment, the stored energy, radiation power, plasma impedance and the antenna's temperature all have positive responses during the short ramp-ups of PL;ICRF. The core ion temperature increased from 1 keV to 1.5 keV and the core heating area expanded from jZj 5 cmto jZj 10 cm during the injection of ICRF waves. In the phasing scanning experiment, in addition to the same conclusions as the previous relatively phasing scanning experiment, the superposition effect of the fluctuation of stored energy, radiation power and neutron yield caused by phasing change with dual antenna, resulting in the amplitude and phase shift, was also observed. The active control of RF output facilitates the precise control of plasma profiles and greatly benefits future experimental exploration.