检索结果-南通市图书馆

In vitro bioactivity and phytochemical screening of Suaeda maritima(Dumort):A mangrove associate from Bhitarkanika,India

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Medicine 2011年第9期4卷 727-734页

作者： JK Patra NK Dhal HN Thatoi department of biotechnology North Orissa UniversityBaripada-757003OdishaIndia department of Natural Products Institute of Minerals and Materials TechnologyBhubaneswar-751013OdishaIndia department of biotechnology College of Engineering and Technology(Bijn Patnaik University of Technology)Bhubaneswar-751003OdishaIndia

Objective:To investigate the in vitro antioxidant and antimicrobial activities along with phytochemical screening of organic and aqueous extracts of leaf and stem of Suaeda maritima (Dumort).a mangrove associate from Bhitarkanika of ***:Antioxidant activity of the crode extracts was evaluated in terms of total antioxidant capacity,total phenol content,ascorbic acid content,DPPH radical scavenging,metal chelating,nitric oxide scavenging,and reducing power *** antimicrobial activity of the plant was determined by agar well diffusion method along with MIC and BBC carried out by microdilulion techniques against 10 gram positive and gram negative human pathogenic *** qualitative and qualitative phytochemical screening were carried out by standard biochemical ***: Out of the seven antioxidant bioassavs,both the leaf and stem extracts were found to posses strong antioxidant properties of 70%to 92%for phenol,total antioxidant capacity,DPPH free radical scavenging aclivitv and fairly good ascorbic acid content,metal chelating(1.33%-22.55%). reducing power(0.01-0.12) and nitric oxide scavenging(0.84%-66.99%) *** of the four extracts evaluated for antimicrobial activity,two leaf extracts such as acetone and ethanol showed promising activity against four pathogenic bacteria and one stem methanol extracts against one pathogenic bacteria when compared with amoxcycillin as *** MIC and MBC values of the antimicrobial extracts ranged between 2.5 to 5.0 mg/*** of phytochemicals showed presence of carbohydrates,protein,tannins,alkaloids and flavonoids in comparatively higher amount than other phytochemicals ***:The present study reveals the presence of potential antioxidants and antimicrobial properties in the plant extract which could be exploited for pharmaceutical application.

关键词： Mangrove plants Suaeda maritima Antioxidant Antimicrobial Phytochemicals

Nuclear magnetic resonance based structure of the protoberberine alkaloid coralyne and its self-association by spectroscopy techniques

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Pharmaceutical Analysis 2019年第6期9卷 437-448页

作者： Kumar Padmapriya Ritu Barthwal department of biotechnology Indian Institute of Technology Roorkee

Coralyne is an important alkaloid due to its anti-cancer and other medicinal *** targets DNA in cells and acts as human topoisomerase-I poison,telomerase inhibitor and nucleic acid *** has high tendency to undergo self-association,which is a matter of concern for therapeutic *** understanding of its interaction with DNA requires precise knowledge of chemical shifts in Nuclear Magnetic Resonance(NMR)spectra besides *** present study is the first report of a complete assignment of all 1H/13C resonances in NMR spectra of coralyne in DMSO-d6 using one dimensional 1H/13C and two dimensional NMR *** chemical shift of all proton and several 13C resonances have also been obtained in D2O and *** same has been calculated using Density Functional Theory(DFT).NMR spectra of coralyne show upfield shift of 0.6e1.2 ppm in aromatic ring protons suggesting stacking *** from 11 intra molecular NOE cross peaks in 2D 1H e1H ROESY spectra,3 short distance NOE correlations,H6e10OCH3,H5e10OCH3 and H12e16CH3,give direct independent evidence of the formation of a stacked *** absorbance,fluorescence,circular dichroism and fluorescence lifetime experiments conducted in the present investigations corroborate results obtained by NMR.

关键词： Coralyne alkaloid NMR spectra Chemical shift calculations Restrained molecular dynamics

Increase in the Transition Enthalpy of Fibrinogen upon Adsorption onto Hydroxyapatite

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1999年第6期16卷 431-433页

作者： CHEN Yong-li MAO Hai-bin ZHANG Xiu-fang GONG Yan-dao ZHAO Nan-ming department of Biological Science and biotechnology State Key Laboratory of Biomembrane and Membrane BiotechnologyTsinghua UniversityBeijing 100084

The increase of the protein transition enthalpy upon adsorption onto biomedical material surfaces was observed by measuringthe differential scanning calorimetry(DSC)traces of bovine fibrinogen adsorbed onto a hydroxyapatite *** mechanism causing the transition enthalpy increase upon adsorption was clariHed by using DSC measurements of bovine fibrinogen for different ionic strength and sodium dodecyl sulfate *** fesu7ts surest that the increased Hbrinogen transition enthalpy may be attributed to the electrostatic interactions between the carboxyl of the D domains and the calcium loci of hydroxyapatite,which may result in a more compact protein structure.

关键词： structure. surface. enthalpy

Effect of Long-Term Intake of Y^(3+) in Drinking Water on Gene Expression in Brains of Rats

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2006年第3期24卷 369-373页

作者：杨维东张萍刘洁生薛艳芳 department of biotechnology Jinan University Guangzhou 510632 China

The rats were fed with water dissolved Y^3＋ at different levels （0, 53.4, 5340 mg·L^-1） for 7 months. The gene expression in brain tissue was detected with oligonucleotide microarray. The results show that, compared to the control, 789 genes express differentially, 507 over-expressed genes and 282 under-expressed genes in the high-dose group （5340 mg· L^-1）, of which, most were related to cell receptor, cell signal and transmission, and ionic passage. 44 genes were found to express differentially including 32 over-expressed genes and 12 under-expressed genes in the low-dose group （53. 40 mg· L^-1）, of which, most were related to cell skeleton and movement, immunity, and DNA binding protein. These resuits suggest that Y^3. can change the expression of some genes, which may be responsible for the toxicity of rare earths on learning and memory.

关键词： gene expression rats cRNA rare earths

Molecular processes in iron and zinc homeostasis and their modulation for biofortification in rice

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2018年第12期60卷 1181-1198页

作者： Yuta Kawakami Navreet K.Bhullar Plant biotechnology Department of Biology ETH Zurich

More than a billion people suffer from iron or zinc deficiencies globally. Rice(Oryza sativa L.) iron and zinc biofortification; i.e., intrinsic iron and zinc enrichment of rice grains, is considered the most effective way to tackle these deficiencies. However, rice iron biofortification, by means of conventional breeding, proves difficult due to lack of sufficient genetic variation. Meanwhile,genetic engineering has led to a significant increase in the iron concentration along with zinc concentration in rice grains. The design of impactful genetic engineering biofortification strategies relies upon vast scientific knowledge of precise functions of different genes involved in iron and zinc uptake, translocation and storage. In this review, we present an overview of molecular processes controlling iron and zinc homeostasis in rice. Further,the genetic engineering approaches adopted so far to increase the iron and zinc concentrations in polished rice grains are discussed in detail, highlighting the limitations and/or success of individual strategies. Recent insight suggests that a few genetic engineering strategies are commonly utilized for elevating iron and zinc concentrations in different genetic backgrounds, and thus, it is of great importance to accumulate scientific evidence for diverse genetic engineering strategies to expand the pool of options for biofortifying farmer-preferred cultivars.

关键词： Molecular processes in iron and zinc homeostasis and their modulation for biofortification in rice Zn

In vitro assessment on medicinal properties and chemical composition of Michelia nilagirica bark

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2017年第9期7卷 782-790页

作者： Babu Venkatadri Ameer Khusro Chirom Aarti Marimuthu Ragavan Rameshkumar Paul Agastian Research department of Plant Biology and biotechnology Loyola College department of Microbiology and biotechnology Presidency College (Autonomous)

Objective: To outline the antibacterial, antioxidant, a-glucosidase inhibition and anticancer properties of Michelia nilagirica(M. nilagirica) bark ***: The antibacterial activity of bark extracts against human pathogens was assessed by disc diffusion assay. Phytochemical screening, total phenols, flavonoids content, antioxidant and a-glucosidase inhibition properties of bark extracts were investigated by standard methods. In vitro anticancer activity of ethyl acetate extract at various concentrations was observed against Hep G2 cells using MTT [3-(4, 5-dimethyl thiazol-2 yl)-2,5-diphenyl tetrazolium bromide] assay. The presence of diverse bioactive constituents in the ethyl acetate extract was identified using FT-IR and GC–MS ***: Ethyl acetate extract was found to be the promising agent against human pathogens tested. The ethyl acetate extracts showed the presence of various phytochemicals and comprised the substantial content of phenolics and flavonoids. The ethyl acetate extract showed better antioxidant activities and also revealed remarkable reducing power ability and a-glucosidase inhibition property. The dose dependent assay of extract showed remarkable cancer cell death with IC_(50) value of(303.26 ± 2.30) mg/m L. FTIR and GC–MS results indicated the presence of major bioactive constituents in the ethyl acetate extract of M. nilagirica ***: Revealing the first report on in vitro biological properties and chemical composition analysis of M. nilagirica bark extract, our study implied that this plant could be of great importance in food and pharmaceutical industries.

关键词： Antibacterial Antioxidant Anticancer Bark extract Michelia nilagirica

Modulation of photovoltaic behavior of dye-sensitized solar cells by electron donors of porphyrin dyes and cosensitization

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2015年第7期26卷 899-904页

作者： Bin Chen Lu Sun Yong-Shu Xie Shanghai Key Laboratory of Functional materials Chemistry East China University of Science and Technology department of Theoretical Chemistry and Biology School of Biotechnology KTH Royal Institute of Technology

Porphyrin dyes have received great attention due to their excellent photovoltaic performance in dye- sensitized solar cells （DSSCs）. In this work, dyes XCI-XC3 were synthesized by introducing various numbers of bis（4-methoxyphenyl）amino and p-hexyloxyphenyl groups to porphyrin meso-positions. The XC1 molecule contains two p-hexyloxyphenyl groups, and its DSSCs showed the power conversion efficiency of 4.81%. For XC2 and XC3, the replacement of p-hexyloxyphenyl with diphenylamino groups can effectively enhance the light harvesting around 500 nm. However, the highest occupied molecular orbitals （HOMOs） were elevated too much, which suppressed the dye regeneration processes, leading to low cell efficiencies of 2.51% and 1.27% for XC2, and XC3, respectively. To further improve the cell performance, an anthracene derivative Cl was used as the cosensitizer for XCl, which increased both the Jsc and Voc values, with an improved efficiency of 5.75：g.

关键词： Porphyrins DSSCs Cosensitizer Theoretical calculation

Estimating the combined toxicity of flufenacet and imazaquin to sorghum with pore water herbicide concentration

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2016年第3期28卷 154-161页

作者： Donghong Wang Qian Zhang Yuan Zheng Dunli Lin Yunlong Yu department of Plant Protection College of Agriculture & BiotechnologyZhejiang University

Combined toxicity of herbicides to non-target crops is usually resulted from their successive *** present study was conducted to assess the combined toxicity of flufenacet（FLU）and imazaquin（IMA）to sorghum with their concentration in soil pore *** concentrations that inhibited growth by 50%（IC50）of FLU and IMA individually and their combination estimated from the herbicide concentrations in soil pore water notably differed from those based on the amended concentrations,due to the decline in bioavailability resulting from adsorption of the herbicides onto *** to the amended concentrations,the combined effect of FLU and IMA in soil on sorghum growth was identified as additive *** on the concentration in soil pore water,however,it was determined to be antagonism,which was identical to that observed in a test using culture *** results revealed that pore water herbicide concentration might be an effective tool to assess the combined toxicity of herbicides in soil to rotational crops.

关键词： Adsorption Bioavailability Combined toxicity Herbicide Pore water

Biosensors: Types, features, and application in biomedicine

在线全文

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2022年第9期12卷 367-373页

作者： Elmira Karami Fatemeh Kazemi-Lomedasht biotechnology Research Center Biotechnology DepartmentPasteur Institute of IranTehranIran

Fast and precise diagnostic techniques are required for the treatment of many *** are one of the diagnostic devices that are applicable in biological and medical *** could be utilized to recognize biological molecules with high *** are consisted of different components and have different *** type of biosensor is used in a particular field according to its specific *** are a novel class of antibodies with small size,high affinity,and specificity to their *** unique properties of nanobodies make them appropriate tools for diagnostic *** this paper,we review biosensors,and their features and roles in ***/nanobody-based biosensors are also specifically discussed.

关键词： Biosensor Nanobody-based biosensor Antibodybased biosensor Biomedicine biotechnology