Biginelli Reaction Synthesis of Novel Multitarget-Directed Ligands with Ca2+ Channel Blocking Ability,Cholinesterase Inhibition,Antioxidant Capacity,and Nrf2 Activation

Novel multitarget-directed ligands BIGI 4a-d and BIGI 5a-d were designed and synthesized with a simple and cost-efficient procedure via a one-pot three-component Biginelli reaction targeting acetyl-/butyrylcholinesterases inhibition, calcium channel antagonism, and antioxidant ability. Among these multitarget-directed ligands, BIGI 4b, BIGI 4d, and BIGI 5b were identified as promising new hit compounds showing in vitro balanced activities toward the recognized AD targets. In addition, these compounds showed suitable physicochemical properties and a good druglikeness score predicted by Data Warrior software.     

利用KS基因筛选Ⅱ型聚酮类化合物产生菌的方法研究

根据酮基合酶编码基因(ketoacyl synthase,KS)的同源性设计简并引物,并利用PCR技术快速筛选携带聚酮类化合物编码基因的放线菌菌株.试验筛选了33株放线菌菌株,检测获得PKSⅡ型阳性菌株16株.克隆并测序获得16条KS基因序列,进行BLAST同源性比对,与GenBank中已知的KS基因序列的相似度在89%~99%之间.提交GenBank,获得的各菌株KS基因登录号为FJ620885~FJ620889,FJ620892,FJ878801~FJ878810.抑菌实验表明,携带KS基因的16株放线菌中,13株具有抑制真菌活性,2株具有抑制革兰氏阳性细菌活性.系统进化树分析表明16株放线菌可以分为7个类群,其中,具有产生新型聚酮类化合物潜力的菌株8株,说明筛选出的KS基因具有一定的多样性.结果表明,利用PCR技术可以快速有效筛选Ⅱ型KS基因,为生物资源的开发利用奠定基础.     

山葵黑根病拮抗菌的筛选和应用

从山葵种植土壤中分离到一株对山葵墨入菌(Phoma wasabiae Yokogi)有强拮抗作用的菌株SA2.通过形态观察、生理生化实验及16S rDNA同源性序列分析,鉴定SA2为一株苏云金芽孢杆菌.盆栽和田间小区实验表明,A2对山葵黑根病有较好的防治效果,田间防效最高达78.98%.     

水霉拮抗菌拮抗活性物质的分离鉴定

本实验采用琼脂扩散法证实,功能拮抗菌株TCCC11322克隆及培养上清,对寄生水霉XJ001生长都有明显的抑制效果,在此实验基础上,对无菌培养上清,进行粗蛋白、粗多糖和肽类物质的分离提取,并对各组分进行了水霉生长拮抗活性检验鉴定,结果证明,培养上清中的分泌性蛋白成分对水霉生长具有明显的抑制效果。     

Synergistic and antagonistic effects of Citrus bergamia distilled extract and its major components on drug resistant clinical isolates

Abstract

In this study we determine the in vitro antimicrobial activities of Citrus bergamia distilled extract and compounds isolated from such extract against clinical MDR strains. The activity of these substances were tested using a broth microdilution assay, their MBC and their FBC to evaluate the nature of the interactions in tested components. Among Gram negative bacteria Enterobacter spp, Klebsiella spp and Pseudomonas spp exhibited the higher MBC values range (2.5–5% v/v). Among Gram positive and Yeast isolates, Corynebacterium spp, Enterococcus faecalis and Staphylococcus spp, as well as Candida lipolytica and lusitanae showed a range of 2.5 to >5% of MBC. To overcome such resistance toward the distilled extract, were used combination of isolated compounds from the same extract. Klebsiella pneumoniae 16/15 and Pseudomonas aeruginosa 7/15 were sensitive to synergistic effect of some tested combinations. Broad spectrum of antimicrobial activity was demonstrated for C. bergamia components and their combinations.     

Antagonism and Molecular Identification of an Antibiotic Bacterium BS04 Against Phytopathogenic Fungi and Bacteria

Through a modified agar well diffusion assay, antagonism of bacterium BS04 is tested. The data show that BS04 has antibiotic activity against phytopathogenic fungi and bacteria, including Phoma wasabiae Yokogi, Cochlibolus Heterostrophu, Exserohilum Turcicum, Curuvularia Lunata (Walk) Boed, Thantephorus cucumris, Fusarium graminearum, Xanthomonas axonopodis pv. Citri (Hasse) Dye and Xanthomonas zingiberi (Uyeda ) Savulescu. The products of bacterium BS04 can endure the treatment of a wide range of pH, and maintain the antibiotic activity after treatment of 100℃ for 30 min. The result suggests that bacterium BS04 has the potential as a promising biocontrol agent. In order to determine the taxonomic placement, the molecular identification of BS04 is performed. The comparative analysis of 16s rDNA sequences indicates that the 16s rDNA sequence of BS04 is highly homologous with sequences of typical Paenibacillus bacteria from the RPD library (from 92% to 99% ). And the constructed phylogenetic tree by using maximum-likelihood method with Bootstrap Trial 1000 proves that BS04 is subjected to Paenibacillus polymyxa.     

一株促生抗病的樱花内生细菌的分离、筛选和鉴定

【目的】解决樱属植物生产过程中根癌病的发生问题。【方法】采用组织分离法和稀释分离法分别从枝干和叶片中分离内生细菌;采用滤纸片法选拮抗菌,通过形态学、生理学和分子生物学法对筛选菌株进行种类鉴定;通过比色法测定筛选菌株的解有机磷的能力;以特定培养基测定菌株产IAA(anxin)的能力,通过测定OD₆₀₀值判断耐NaCl的能力。【结果】在樱花体内共分离到32株内生细菌,其中从枝条内分离到28株,从叶片内分离到4株。对32株内生细菌进行抑菌活性的筛选,有2株对根癌农杆菌(Agrobacterium tumefaciens)有明显的抑制作用。另对其中的1株细菌YH-20进行鉴定,鉴定结果为瓦雷兹芽孢杆菌(Bacillus velezensis)。菌株YH-20具有良好的解有机磷和无机磷作用,其在第7天的解无机磷的量为178.43 mg/L,在第7天解有机磷的量为76.50 mg/L;具有较高的分泌IAA的能力,在第7天IAA的生成量为9.174 μg/mL;可在含10% NaCl的培养基上正常生长。【结论】筛选获得的瓦雷兹芽孢杆菌YH-20菌株具有抗植物根癌病菌和解磷能力,是一株在林木根癌病的防治上有很好应用前景的菌株。     

酸枣仁皂甙A──新型的钙调蛋白天然拮抗剂

报导了具有宁心、安神等功效的中药酸枣仁的主要成分之一——酸枣仁皂甙Ａ， 它是钙调蛋白（ＣａＭ）的一种新型天然拮抗剂，以不含氮而区别于其它天然拮抗剂。酸 枣仁皂甙Ａ能有效地抑制ＣａＭ活化的环腺苷酸磷酸二酯酶（ＰＤＥ）的活力，其ＩＣ５０值 为 １５μｍｏｌ／Ｌ，是目前已发现的拮抗能力较强的一种 ＣａＭ天然拮抗剂。动力学研究表 明，酸枣仁皂甙Ａ对ＣａＭ活化ＰＤＥ活力的抑制是按非竞争性抑制方式进行的。     

Interactions of Ascorbic Acid, 5-Caffeoylquinic Acid,and Quercetin-3-Rutinoside in the Presence and Absence of Iron during Thermal Processing and the Influence on Antioxidant Activity

Bioactive compounds in fruit and vegetables influence each other’s antioxidant activity. Pure standards, and mixtures of the common plant compounds, namely ascorbic acid, 5-caffeoylquinic acid, and quercetin-3-rutinoside (sum 0.3 mM), in the presence and absence of iron, were analyzed pre- and post-thermal processing in an aqueous solution. Antioxidant activity was measured by total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (TEAC) radical-scavenging assays. Ionic ferrous iron (Fe²⁺) and ferric iron (Fe³⁺) were measured photometrically. For qualification and quantification of reaction products, HPLC was used. Results showed that thermal processing does not necessarily lead to a decreased antioxidant activity, even if the compound concentrations decreased, as then degradation products themselves have an antioxidant activity. In all used antioxidant assays the 2:1 ratio of ascorbic acid and 5-caffeoylquinic acid in the presence of iron had strong synergistic effects, while the 1:2 ratio had strong antagonistic effects. The pro-oxidant iron positively influenced the antioxidant activity in combination with the used antioxidants, while ferrous iron itself interacted with common in vitro assays for total antioxidant activity. These results indicate that the antioxidant activity of compounds is influenced by factors such as interaction with other molecules, temperature, and the minerals present.