Prebiotic Potential of Xylooligosaccharides Derived from Corn Cobs and Their In Vitro Antioxidant Activity When Combined with Lactobacillus

( Xiuhua Yu ),( Jianyuan Yin ),( Lin Li ),( Chang Luan ),( Jian Zhang ),( Chunfang Zhao ),( Shengyu Li ) 한국미생물 · 생명공학회 2015 Journal of microbiology and biotechnology Vol.25 No.7

In the present work, the in vitro prebiotic activity of xylooligosaccharides (XOS) derived from corn cobs combined with Lactobacillus plantarum, a probiotic microorganism, was determined.These probiotics exhibited different growth characteristics depending on strain specificity. L. plantarum S2 cells were denser and their growth rates were higher when cultured on XOS. Acetate was found to be the major short-chain fatty acid produced as the end-product of fermentation, and its amount varied from 1.50 to 1.78 mg/ml. The antimicrobial activity of XOS combined with L. plantarum S2 was determined against gastrointestinal pathogens. The results showed that XOS proved to be an effective substrate, enhancing antimicrobial activity for L. plantarum S2. In vivo evaluation of the influence of XOS and L. plantarum S2, used both alone and together, on the intestinal microbiota in a mouse model showed that XOS combined with L. plantarum S2 could increase the viable lactobacilli and bifidobacteria in mice feces and decrease the viable Enterococcus, Enterobacter, and Clostridia spp. Furthermore, in the in vitro antioxidant assay, XOS combined with L. plantarum S2 possessed significant 2,2-diphenyl-1- picrylhydrazyl, 2,2’-azino-bis, and superoxide anion radical-scavenging activities, and the combinations showed better antioxidant activity than either XOS or L. plantarum S2 alone.

PREPARATION OF FOLATE-CONJUGATED BOVINE SERUM ALBUMIN NANOPARTICLES ADSORBING EPIRUBICIN HYDROCHLORIDE

XIUHUA ZHAO,JIAMING TANG,YUANGANG ZU,WEIGUO WANG,NA LI,WENJIA XU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.6

This work investigated the preparation process of folate-conjugated bovine serum albumin nanoparticles (FA–BSANPs) adsorbing epirubicin hydrochloride (EPI) nanoparticles (FA–EPI–BSANPs), a specific-targeting drug delivery system in cancer chemotherapy. The BSANPs were prepared by desolvation as a drug carrier system and conjugated with folate to produce FA–EPI–BSANPs that specifically target tumors by cross-linking. EPI, an anticancer drug, was adsorbed by this drug carrier system. The influences of six experimental parameters, namely, the adsorption time, FA–BSANPs solution-adsorbed EPI concentration, stirring speed, FA–BSANPs solution pH, the ratio of glutaraldehyde and BSA, and mass ratio of FA–BSANPs to EPI, on the drug loading efficiency (DLR) and drug entrapment efficiency (DER) of FA–EPI–BSANPs were investigated via the single factor method. The results indicated that the optimum operation conditions were obtained with 145.4 nm±0.5 nm MPS, 23.41% DLR and 98.93% DER. The N-hydroxysuccinimide-folate content associated with BSANPs was up to 0.9757% (wt). The DLR and DER of EPI increased with increasing adsorption time, FA–BSANPs solution concentration, and pH value, peaking at 1750 rpm with increasing stirring speed, but decreasing thereafter. The FA–EPI–BSANPs obtained were characterized by laser light scattering, scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and thermogravimetric analysis. Drug release in vitro was investigated, as well. The characterization results showed that EPI in FA–EPI–BSANPs existed in an amorphous, instead of crystalline state. Most of the EPI was enclosed by FA–BSANPs, and a small amount was adsorbed onto the surface of the FA–BSANPs. The FA–EPI–BSANPs particles are nearly ellipsoidal and significantly affect sustained release. The inhibitory rate of FA–EPI–BSANP was mensurated by MTT method. The inhibitory rate of FA–EPI–BSANPs for SMMC 7721 cell developed with raise of concentration and was higher than other samples. The IC50 values of FA–EPI–BSANPs and EPI were 11.5 μg/mL and 18.8 μg/mL, respectively. The target ability of FA–EPI–BSANP for SMMC 7721 cell was mensurated by fluorescence (FITC) modified albumin techniques. The uptake rate of FA–EPI–BSANPs was higher than samples without folate conjugated, and increased with increased concentration.

Preparation of a Novel Three-Dimensional TiO2 Macroporous/TiO2 Nanorods/Ag Nanoparticles Composite Nanostructure and its Use as SERS Substrates

Xiuhua Li,Jian Lin,Junhong Zhao 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.5

A novel composite nanostructure which is made up of TiO2 three dimensionally ordered macroporous (3DOM) nanostructure and TiO2 nanorods (NRs) has been successfully synthesized through a combination of colloidal crystal template technology and hydrothermal method, then we achieved its combination with Ag nanoparticles (NPs) via a silver mirror reaction. We studied the SERS (Surface-Enhanced Raman Scattering) performance of the obtained structure, the results show that our samples are very sensitive substrates when being used to detect dye R6G molecules, with a low detection concentration of 10 -11 M. This proves that it is a promising material in the area of analyzing and molecule-level detecting as a kind of novel and low-cost SERS substrate.

A bidirectional valveless piezoelectric micropump with three chambers applying synthetic jet

Xiuhua He,Liang Xu,Xitong Zhang,Song Yang 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.9

A new type of valveless piezoelectric micropump is presented. Synthetic jet and Coanda effect are utilized to achieve larger and bidirectional flow rate. The numerical simulation applying the velocity and pressure boundary conditions as well as the SST turbulence model were utilized to research the performance and internal flow state of the micropump. The simulation method was tested by the previous experimental data and the results matched well. The results suggest that the flow rate of the micropump is related to the Reynolds number and frequency. The entrainment flow rate of synthetic jet accounts for over 80% of the total outflow rate. The outflow rate is much larger than the volume change of the micropump chambers. There is an optimal frequency to obtain the maximum flow rate regarding the volume change of the chambers as a constant. The fluctuation of the flow rate decreases with the increase of frequency. When the frequency is higher than 25 Hz, the outflow can be continuous. Working at the Reynolds number of 1000 and optimal frequency of 50 Hz, the flow rate is 6.8 ml/min.

Mechanical Properties of Special-shaped Mo Fiber Reinforced Mineral-filled Polymer Composite

Xiuhua Ren,Chao Zhang,Jianhua Zhang,Peng Liu,Guangjiu Qin 한국섬유공학회 2021 Fibers and polymers Vol.22 No.2

With superior vibration alleviation property, mineral-filled polymer composite (MFPC) has attracted moreattention in the field of mechanical manufacturing. However, the application of MFPC is limited by its inferior mechanicalstrength. Straight-line and special-shaped Mo fibers were respectively added into MFPC to improve its mechanical propertiesin the paper. The influences of fiber shape and matrix performance on interface bonding property of fiber-matrix were studiedsystematically. And the effects of fiber shape and fiber content on compressive and flexural strength of MFPC wereseparately discussed. Finite element analysis was employed to further verify experimental results. Compared with straightlinefiber, both pulling ability and interfacial bonding strength of special-shaped Mo fiber are greatly improved when massratio r of resin and curing agent is identical. For the same fiber, interface bonding strength of r=4:1 is obviously greater thanthat of r=7:1. The maximum mechanical strength is achieved when mass fraction of fibers is 1.2 %. Mechanical properties ofMFPC reinforced by special-shaped fibers are much better than those reinforced by straight-line fibers. By contrast, thereinforcing effect of M-shaped fibers is optimal, followed by N-shaped, U-shaped the third, and V-shaped the minimum,which consists with the results of finite element simulation.

A Fuzzy Identity-Based Signcryption Scheme from Lattices

( Xiuhua Lu ),( Qiaoyan Wen ),( Wenmin Li ),( Licheng Wang ),( Hua Zhang ) 한국인터넷정보학회 2014 KSII Transactions on Internet and Information Syst Vol.8 No.11

Fuzzy identity-based cryptography introduces the threshold structure into identity-based cryptography, changes the receiver of a ciphertext from exact one to dynamic many, makes a cryptographic scheme more efficient and flexible. In this paper, we propose the first fuzzy identity-based signcryption scheme in lattice-based cryptography. Firstly, we give a fuzzy identity-based signcryption scheme that is indistinguishable against chosen plaintext attack under selective identity model. Then we apply Fujisaki-Okamoto method to obtain a fuzzy identity-based signcryption scheme that is indistinguishable against adaptive chosen ciphertext attack under selective identity model. Thirdly, we prove our scheme is existentially unforgeable against chosen message attack under selective identity model. As far as we know, our scheme is the first fuzzy identity-based signcryption scheme that is secure even in the quantum environment.

MALDI-TOF-MS analysis of small molecules using modified mesoporous material SBA-15 as assisted matrix

Li, Xiuhua,Wu, Xue,Kim, Ji Man,Kim, Sung Soo,Jin, Mingshi,Li, Donghao Springer-Verlag 2009 Journal of the American Society for Mass Spectrome Vol.20 No.11

<P>Mesoporous silica, SBA-15 was successfully functionalized with quinoline moiety, and was applied as a matrix in the MALDI-TOF-MS analysis of small molecules. The modified SBA-15 material [SBA-15-8-(3-(triethoxysilyl)propoxy) quinoline, SBA-15-8QSi] was obtained by using calcined SBA-15 and 8-hydroxy quinoline. The structure of the functionalized mesoporous material was systemically characterized by TEM, the N<SUB>2</SUB> adsorption-desorption isotherm technique and FT-IR spectra. Compared with DHB and SBA-15, SBA-15-8QSi demonstrated several advantages in the analysis of small molecules with MALDI-TOF-MS, such as less background interference ions, high homogeneity, and better reproducibility. Based on these results, the various analytical parameters were optimized. The ideal operating conditions were (1) methanol used as the dissolving solvent; (2) sample first dropping method; (3) a ratio between the analyte and the matrix of 3.5:10. Under these optimization conditions, a low detection limit (8 pmol for L-Arginine-HCl) and high reproducibility (≤29%) were obtained. This technique was successfully applied to the analysis of various types of small molecules, such as saccharides, amino acids, metabolites, and natural honey.</P>

중국인 학습자의 한국어 접촉 정도가 요청 화행에서의 공손 표현 실현에 미치는 영향

Peng Xiuhua,김영주 한국국어교육학회 2021 새국어교육 Vol.- No.129

Purpose: this study aimed to investigate the ability of Chinese learners of Korean to use polite expressions along with influence of the amount of contact with Korean and some other factors on the Korean polite expressions of Chinese Korean learners in the target language area. Method: all forty Chinese student participants who study in South Korea and twenty-one Korean native speakers were asked to finish the ODCT for obtaining the data of Chinese speakers’ polite expression and baseline data, respectively. Chinese students were also asked to finish the LCP for getting their data on the amount of contact with Korean as well. Result: according to the results of regression analysis, the amount of contact with Korean showed a positive effect on the polite expressions. The polite expressions of Chinese learners who have larger amount of contact with Korean (e.g., productive and more interactive type of language contact) were found to be close to that of Korean native speakers. Conclusion: Depending on the Korean Proficiency is not enough for learners having properly usage of polite expression ability. The contact of high interactive and productive conversations is also needed. In this regard, we offer different conversations with various social background (e.g., social status and affinities) which are close to the real conversation in our daily life. 목적: 본 연구는 목표어 환경에서 중국인 학습자의 한국어 공손 표현 실현은 어떠한지 또 학습자 변인 특히 한국어 접촉 정도가 공손 표현 실현에 영향을 미치는지 알아보는 데에 있다. 방법: 한국에 있는 중국인 학생 40명을 대상으로 요청 화행에서 그들의 공손 표현 실현을 분석하기 위해 ODCT를 시행하였고 비교 분석을 위해 한국어 모어화자 21명도 ODCT에 참여하였다. 또한 언어접촉 정도 설문으로 한국어 접촉 정도를 조사하였다. 결과: 회귀 분석을 통해 한국어 접촉 정도가 중국인 학습자의 공손 표현 실현에 긍정적인 영향을 미치며, 특히 생산성이 높은 접촉의 영향이 더 큼을 확인하였다. 결론: 학습자가 공손 표현을 적절하게 산출할 수 있는 능력을 갖추고자 하면 한국어 지식에 대한 숙달도만으로는 부족하고 상호작용이 강하고 생산성이 높은 회화 접촉이 필요하다. 이에 교실 현장에서 실제 담화와 같이 사회적 지위와 친소 관계와 같은 사회적 규칙이 정해진 다양한 대화 연습의 기회를 제공해야 할 것이다.

The Mind in Process: Meaning of Chinese philosophy of Mind on Mind Ecology Studies

Zhang Xiuhua 한국마음학회 2013 한국마음학회 학술대회논문집 Vol.2013 No.1

Traditional Chinese Philosophy is different with the Western Philosophy as metaphysics of substance and epistemology for inquiry cosmos, world and knowledge. Its interest lies in considering the relationship between man and world, man and man, man and himself, in order to construct ethic aesthetical and value world of meaning. Therefore, Chinese Philosophical Human Studies of humanism directly concern the issue of mind. There is not only theory of Mind-Nature, but also many scholars regard Confucianism as Philosophy of Mind, so that some see Chinese Philosophy as Philosophy of Mind. These understanding are coincident with postmodern Mind Ecology Studies in the perspective of Process Philosophy, so we. can say that Chinese Philosophy of Mind has the meaning of Mind Ecology Studies, and the latter further demonstrates the contemporary theoretic value and meaning of practice from Chinese Philosophy of Mind. Hence, three issues have to be discussed in this paper. First one is the Mind as Absolute Subject and Its Characters. The traditional Chinese Philosophy always see mind as an absolute subject which dominates everything, concerns everything in the universe, moreover, the mind as absolute subject has characters of wholeness and introversion. Second one is The Mind with Praxis Function for Growing and Developing. The growing and developing is a process, so the mind is not entity but spiritual praxis for actualizing Sage Realm of morality. In the course, various factors and relations of the mind get synergy in the thinking of organism and holism. Third one is Seeing Chinese Philosophy of Mind from Mind Ecology Studies.

The periplasmic chaperone protein Psg_2795 contributes to the virulence of Pseudomonas savastanoi pv. glycinea: the causal agent of bacterial blight of soybean

Wang Xiuhua,Zhang Xiaoyan,Lu Bao-Hui,Gao Jie 한국미생물학회 2022 The journal of microbiology Vol.60 No.5

Pseudomonas savastanoi pv. glycinea (Psg, also named P. syringae pv. glycinea and P. amygdali pv. glycinea) is the causative agent of bacterial blight in soybean. The identification of virulence factors is essential for understanding the pathogenesis of Psg. In this study, a mini-Tn5 transposon mutant library of Psg strain PsgNC12 was screened on soybean, and one low-virulent mini-Tn5 mutant, designated as 4573, was identified. Sequence analysis of the 4573-mutant revealed that the mini-Tn5 transposon was inserted in the Psg_2795 gene. Psg_2795 encodes a FimC-domain protein that is highly conserved in Pseudomonas. Further analysis revealed that the mutation and knockout of Psg_2795 results in a reduced virulence phenotype on soybean, decreased motility, weakened bacterial attachment to a glass surface and delayed the population growth within soybean leaves. The phenotype of the 4573-mutant could be complemented nearly to wild-type levels using an intact Psg_2795 gene. Collectively, our results demonstrate that Psg_2795 plays an important role in the virulence, motility, attachment and the population growth of PsgNC12 in soybean. This finding provides a new insight into the function of periplasmic chaperone proteins in a type I pilus and provides reference information for identifying Psg_2795 homologues in P. savastanoi and other bacteria.