Studies on the Mode of Action of Organophosphorus Compounds

It was presumed in the previous paper that sumithion was easily absorbed from the gastrointestestinal tract, similarly to methylparathion, following the oral administration to mammals. Inhibition of blood and brain cholinesterase of Guinea pigs and white rats in vivo after oral treatment with sumithion and methylparathion was determined. Inhibition of the enzymes was found to proceed rather rapidly and in most cases it reached maximum within one hour. Sumithion hindered the brain cholinesterase activity far less effectively than methylparathion. Intravenous administration of these phosphorothioates and their oxygen analogs clarified that the latters were more inhibitory on the cholinesterases and that of the two oxygen analogs, sumioxon was less effective. The poor susceptibility of the brain enzyme to sumithion was also observed in this case. This paper deals with the experimental results and their possible implications in the toxicity of the organophosphorus compounds toward mammals.     

Studies on the Mode of Action of Organophosphorus Compounds

For the purpose of distinguihsing sumithion from methylparathion in the mammalian metabolism, phosphorus³² labeled compounds were administered to Guinea pig and white rat. Both compounds were found to be absorbed readily, and phosphorus containing metabolites excreted chiefly into urine. By chromatographic separation and identification of the metabolites, the decomposition of sumithion was observed to proceed presumably more easily than methylparathion. From these results lower toxicity of the former toward mammals than the latter was discussed. In addition, compounds remaining in rice plant and German cockroach were also analysed.     

Studies on the Mode of Action of Organophosphorus Compounds

In order to further elucidate the mechanism of metabolic difference between sumithion and methylparathion, distribution of sumithion and methylparathion into several tissues, activation, that is, conversion into more toxic oxygen analogs, and degradation into non-toxic compounds were examined in vivo following the intravenous administration of the phosphorothioates to Guinea pigs and white rats. Sumioxon and methylparaoxon were detected in all tissues tested, among which lung and liver were richest in them. More sumioxon than methylparaoxon was found. Chese organophosphorus compounds were found to be decomposed to non-toxic desmethyl compounds and dimethyl phosphorothioic acid mainly in liver and kidney. From these results it seems improbable that the lower toxicity of sumithion than that of methylparathion results from the different in their rate of metabolism.     

Anti-inflammatory Activity of Bioactive Compounds from Microalgae and Cyanobacteria by Focusing on the Mechanisms of Action

Molecular Biology Reports - Microalgae and cyanobacteria are the potentially valuable source of bioactive compounds applied in the various industries and human usage in different fields of...     

水稻条纹病毒胁迫下的水稻全基因组表达谱

水稻条纹叶枯病由水稻条纹病毒(Rice stripe virus, RSV)引起,对我国水稻生产危害严重.为了明确RSV侵染对水稻基因表达谱的影响,采用Affymetrix水稻全基因组芯片对RSV接种后出现条纹症状第7天的武育粳3号水稻病叶和相应的健康叶片进行了全基因组表达谱分析,得到3 517个差异基因,其中2 002个表达上调,1 515个表达下调.根据TIGR数据库注释(http://www.tigr.org/tdb/e2k1/osa1/)和MIPS基因功能分类标准(http://mips.gsf.de/projects/funcat)将差异基因归类为15个功能类别,多数差异基因与植物防御、信号传导及蛋白质、碳水化合物的代谢相关,一些转录因子的表达也发生了明显的变化.代谢途径分析表明,RSV侵染后磷酸戊糖途径、类黄酮合成途径和芸苔素合成途径的相关基因表达明显增强,赤霉素合成途径相关基因的表达受到了抑制.     

Metabolic Profiling in Banana Pseudo-Stem Reveals a Diverse Set of Bioactive Compounds with Potential Nutritional and Industrial Applications

Banana (Musa spp.) is an ancient and popular fruit plant with highly nutritious fruit. The pseudo-stem of banana represents on average 75% of the total dry mass but its valorization as a nutritional and industrial by-product is limited. Recent advances in metabolomics have paved the way to understand and evaluate the presence of diverse sets of metabolites in different plant parts. This study aimed at exploring the diversity of primary and secondary metabolites in the banana pseudo-stem. Hereby, we identified and quantified 373 metabolites from a diverse range of classes including, alkaloids, flavonoids, lipids, phenolic acids, amino acids and its derivatives, nucleotide and its derivatives, organic acids, lignans and coumarins, tannins, and terpene using the widely-targeted metabolomics approach. Banana pseudo-stem is enriched in metabolites for utilization in the food industry (L-lysine and L-tryptophan, L-glutamic acid, Phenylalanine, Palmitoleic acid, α-Linolenic acid, and Lauric acid, and Adenine) and pharmaceutical industry (Guanosine and Cimidahurinine, Bergapten, Coumarins, Procyanidin A2, Procyanidin B1, Procyanidin B3, Procyanidin B2, and Procyanidin B4, Asiatic acid). The metabolome of banana pseudo-stem with integration across multiomics data may provide the opportunity to exploit the rich metabolome of banana pseudo-stem for industrial and nutritional applications.     

HPLC法分析山姜属植物中的8种活性成分

本文采用高效液相色谱方法,对18份16种山姜属植物中的8种抗血小板聚集活性成分进行了分析.这8种成分包括山姜素、豆蔻明、4',7-二羟基-5-甲氧基二氢黄酮、蜡菊亭、5,6-去氢醉椒素、4'-羟基去氢醉椒素、1,7-二(4-羟基苯基)-3-羟基-1,3,6-庚三烯-5-酮和1,7-二(4-羟基苯基)-3-羟基-1,3-庚二烯-5-酮.其中,对山姜素和豆蔻明进行了含量测定,其余6种成分进行了定性分析.结果表明这些山姜属植物有不同的化学成分特征.山姜素和豆蔻明是草豆蔻种子的主要特征成分,艳山姜种子中检测到较多的5,6-去氢醉椒素.     

HPLC/HR-MS-Based Metabolite Profiling and Chemometrics: A Powerful Approach to Identify Bioactive Compounds from Abarema cochliacarpos

Despite its importance as a medicinal plant, there is a lack of studies that assessed the chemical composition of A. cochliacarpos extracts. Herein, we used a metabolite profiling approach and chemometrics as a powerful strategy to correlate the chemical composition with the antioxidant activity of A. cochliacarpos extracts. Extracts obtained with ethyl acetate showed greater antioxidant activity and higher total phenolic content than extracts obtained with hexane. The chemical composition was assessed by HPLC/HR-MS and it encompassed fatty alcohols, terpenoids, phenolic derivatives, lipids, carotenoid-like compounds, alkaloids, flavonoids, polyketides, and glycerophospholipids. Chemometrics successfully differentiated not only the chemical composition of extracts in response to the nature of the extraction solvent and the botanical part used during extraction but also it allowed us to associate the chemical composition with the antioxidant activity of the extracts, which might be particularly helpful for drug discovery and development programs.     

Enzymic Breakdown of Amino Acids and Related Compounds by Suspensions of Washed Mycobacteria

The ability of washed mycobacteria, harvested from Lowestein-Jensen medium, to break down amino acids and related compounds was investigated. One hundred and thirty mycobacteria representing 17 species were tested against 21 compounds. Three compounds were broken down by all strains, seven were not attacked by any strain and in the remainder there was variable degradation both between and within species.     

Mode of Action of α, β Unsaturated Carbonyl Compounds

The toxicity of the α, β unsaturated carbonyl compounds (α, β UCC_s) (patulin, penicillic acid, parasorbic acid, tulipalin and plumbagin) towards Pythium sp. group F (Van Der Plaat -Niterinks 1981) was neutralized by the addition of an excess of cysteine. This suggests that the mode of action of these compounds could be due to a binding of the α, βi UCC_s to sulphydryl groups in enzymes or other macromolecules. Alcohol dehydrogenase (ADH), an enzyme with a sulphydryl group at the active site, was assayed spectrophotometrically and all the α, β UCC_s inhibited ADH.     

A compilation of Bioactive Compounds from Ayurveda

This review deals with the key bioactive compounds and the role of medicinal plants in Ayurvedic systems of medicine in India and their earlier investigation. There has been an increase in demand for the Phytopharmaceutical products of Ayurvĕda in Western countries, because of the fact that the allopathic drugs have more side effects. Many pharmaceutical companies are now concentrating on manufacturing of Ayurvĕdic Phytopharmaceutical products. Ayurvĕda is the Indian traditional system of medicine, which also deals about pharmaceutical science. Different type of plant parts used for the Ayurvedic formulation; overall out line of those herbal scenario and its future prospects for the scientific evaluation of medicinal plants used by traditional healers are also discussed. In India most of them, where Ayurvedic treatment is frequently used, for their ailments and provides instructions to local people how to prepare medicine from the herbs. As much as possible importance is also given for the taxonomic literature.     

江南牡丹草的化学成分研究

江南牡丹草 Leontice kiangnanensis,别名江南玄胡 ,主要分布在浙江西北部和安徽皖南山区。民间草药 ,药用块茎 ,有清热解毒、活血化瘀功效 ;用于治疗跌打损伤、骨折疼痛、头痛、吐血、外伤出血等症 ,疗效显著。其化学成分研究未见报道。我们从江南牡丹草块茎水溶性生物碱中分离得到 1 5个生物碱成分 ,报道了其中 7个已知化合物 ,其它 8个生物碱的结构另文报道。1 　实验部分1 .1 　实验仪器与材料熔点用 X-4型显微熔点仪测定 (温度计未校正 )。红外光谱用 Perkin-Elmer 983型红外光谱仪测定 ,溶剂为 CDCl3和 CDOD,TMS内标。质谱用 V…     

Volatile Nitrogenous Compounds from Bacteria: Source of Novel Bioactive Compounds

Bacteria can produce nitrogenous compounds via both primary and secondary metabolic processes. Many bacterial volatile nitrogenous compounds produced during the secondary metabolism have been identified and reported for their antioxidant, antibacterial, antifungal, algicidal and antitumor activities. The production of these nitrogenous compounds depends on several factors, including the composition of culture media, growth conditions, and even the organic solvent used for their extraction, thus requiring their identification in specific conditions. In this review, we describe the volatile nitrogenous compounds produced by bacteria especially focusing on their antimicrobial activity. We concentrate on azo-compounds mainly pyrazines and pyrrolo-pyridines reported for their activity against several microorganisms. Whenever significant, extraction and identification methods of these compounds are also mentioned and discussed. To the best of our knowledge, this is first review describing volatile nitrogenous compounds from bacteria focusing on their biological activity.