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Identification and sequence analysis of two thaumatin‐like protein (TmTLP) genes from Tenebrio molitor 下载免费PDF全文
Thaumatin‐like proteins (TLPs) share structural similarity with the sweet‐tasting thaumatin protein but exhibit antifungal activity by inhibiting growth of fungal pathogens. In a Tenebrio model, two TLP genes were identified by RNA‐sequencing analysis and genome sequencing. Both TmTLP1 and TmTLP2 genes contain 729 nucleotide sequences encoding 242 amino acid residues, including an initiation codon (ATG) and a termination codon (TAA). Interestingly, TmTLPs are proteins with 14 central cysteine residues that may have an important role in structure formation. These data will be used to characterize the innate immune functions of TmTLPs in Tenebrio molitor. 相似文献
95.
《Bioorganic & medicinal chemistry》2016,24(16):3649-3656
Novel benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) precursors, these NHC precursors were metallated with Ag2O in dichloromethane at room temperature to give novel silver(I)–NHC complexes. Structures of these benzimidazolium salts and silver(I)–NHC complexes were characterized on the basis of elemental analysis, 1H NMR, 13C NMR, IR and LC–MS spectroscopic techniques. A series of benzimidazolium salts and silver(I)–NHC complexes were tested against standard bacterial strains: Enterococcus faecalis, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and the fungal strains: Candida albicans and Candida tropicalis. The results showed that benzimidazolium salts inhibited the growth of all bacteria and fungi strains and all silver(I)–NHC complexes performed good activities against different microorganisms. 相似文献
96.
Muhammed Akif Akgz 《化学与生物多样性》2019,16(12)
Phytochemicals, which are commonly found at different levels in many medicinal plants, are natural strong antioxidants used in traditional medicine. In this research, determination of differences of phytochemical compositions and biological properties were aimed as periodically (pre‐, full and post flowering) and daily (6 am, 1 pm and 8 pm) in Achillea gypsicola Hub.‐Mor . The volatile oils belonging to A. gypsicola were obtained by hydrodistillation and analyzed by gas chromatography‐flame ionization detection (GC‐FID) and gas chromatography‐mass spectrometry (GC/MS). The antimicrobial activities of the volatile oils were determined with disc diffusion method. The microdilution method was used to determine minimum inhibitory concentration (MIC). Total phenolic and flavonoid contents were determined by spectrophotometric methods and antioxidant capacities were evaluated by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) free radical, reducing power (RP) and metal chelating activity (MCA) assay. In addition, the phenolic acid and flavonoid compositions were evaluated by reversed phase‐high‐performance liquid chromatography (RP‐HPLC). This study presented a comprehensive report for the first time on evaluation of the phytochemical composition and the biological properties of A. gypsicola at different phenological stages. Thirty‐two compounds, containing the major component as camphor, 1,8‐cineole and borneol, were detected. Designated harvest time for the highest yield of volatile oils was found to be at full flowering stage‐1 pm. It has been observed that the volatile oil composition changes periodically and even daily. Also, in this research, menthol and menthone were found as the composition of volatile oil in Achillea species for the first time. Full flowering stage was found as the richest period in terms of phenolic acid and flavonoid compositions of A. gypsicola for the first time. The species examined in this research showed a high antioxidant and antimicrobial activity in comparison to other studies with Achillea species. The volatile oils exhibited high performances with range of inhibition zones (8.3–42.3 mm) and minimum inhibitory concentration values (2.25—144 μg/ml). Besides, a high correlation between antioxidant activity and phenolic content of A. gypsicola was found. These results suggest that A. gypsicola can be used as a safe source in the cosmetic, food and pharmaceutical industries. 相似文献
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Hacer Tugba Degirmencioglu Etil Guzelmeric Parla Isil Yuksel Hasan Krmzbekmez Inci Deniz Erdem Yesilada 《化学与生物多样性》2019,16(12)
This study was undertaken to analyze the phenolic profiles of 19 propolis samples from Turkey by using a high‐performance thin‐layer chromatographic (HPTLC) method in order to identify their plant origins. Furthermore, their antioxidant and antimicrobial activity profiles were comparatively evaluated. For the appraisal of antioxidant potential, total phenolic (TPC) and total flavonoid contents (TFC) of propolis samples were firstly determined and then their effects on free radicals were evaluated by FRAP, ABTS.+, CUPRAC, DPPH. and HPTLC‐DPPH. methods. Antimicrobial activity of propolis samples against Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 11229) and Candida albicans ATCC 10231 were determined by disc diffusion and broth dilution methods. HPTLC fingerprinting analyses revealed that O‐type (botanical origin from Populus nigra L.) was the primarily available propolis type in Turkey. Moreover, 3‐O‐methylquercetin (3MQ) rich propolis was identified as a new propolis type for the first time. Principal component analysis (PCA) indicated that 3MQ‐type propolis differs from the O‐type. Antioxidant activity studies showed that O‐type of propolis possesses higher antioxidant effect than the other tested propolis types. Quercetin, caffeic acid, caffeic acid phenethyl ester (CAPE) and galangin were determined to contribute significantly to the antioxidant potential of O‐type propolis among others. Propolis extracts exerted moderate antimicrobial activity against the tested microorganisms with MIC values between the ranges of 128–512 μg/mL. 相似文献
98.
Sheng‐Xiang Yang Wen‐Ting Zhao Heng‐Ye Chen Lei Zhang Ting‐Kai Liu He‐Ping Chen Jian Yang Xiao‐Long Yang 《化学与生物多样性》2019,16(9)
Two new C13‐polyketides, aureonitols A and B ( 1 and 2 ), along with five known compounds ( 3 – 7 ), were isolated from the solid fermentation culture of the plant endophytic fungus Chaetomium globosum from the aerial parts of Salvia miltiorrhiza. The structures and absolute configurations of 1 and 2 were determined by comprehensive spectroscopic data analysis and computed methods. Compound 5 was found to display the remarkable antimicrobial activities against four multidrug‐resistant bacteria (Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, and Staphylococcus epidermidis) with MIC values of 3.13–6.25 μg/mL (ciprofloxacin: 0.78–1.56 μg/mL), and also against all tested fungal strains with MIC values of 3.13–25 μg/mL (ketoconazole: 0.78–12.50 μg/mL). 相似文献
99.
S. Amat D. Baines E. Timsit J. Hallewell T.W. Alexander 《Journal of applied microbiology》2019,126(6):1668-1682
100.
H.T. Nguyen S. Kim N.H. Yu A.R. Park H. Yoon C.-H. Bae J.H. Yeo I.S. Kim J.-C. Kim 《Journal of applied microbiology》2019,126(3):894-904