Использование методологии SAR для идентификации аллелохемиков пресноводных макрофитов с высоким антицианобактериальным эффектом в отношении планктонных цианобактерий

Controlling harmful cyanobacterial “blooms” through developing a new generation of algaecides based on allelochemical substances is a challenge facing modern aquatic ecology and biotechnology. The present article is devoted to the use of the SAR (Structure-Activity-Relationship) information technology to identify allelochemicals from aquatic macrophytes (floating-leaved Nuphar lutea (L.) Sm. and several species of submerged macrophytes: Ceratophyllum demersum L., Myriophyllum spicatum L., Elodea canadensis Michx, and species of the genus Potamogeton) effective against planktonic cyanobacteria. Detection and identification of compounds were performed using gas chromatography-mass spectrometry. The PASS (Prediction of Activity Spectra for Substances) computer program has been applied to predict biological activity spectra of the major components of macrophyte metabolomes and discover their ecological potential against cyanobacteria. A study of the biological activities of major low-molecular-weight organic compounds showed that monocarboxylic acids, gallic acid, cis‑6-octadecenoic acid, cis‑9-octadecenoic acid, palmitoleic acid, linolenic acid, and 9-cis‑12-cis-linoleic acid are the most promising compounds for the experimental verification and creation of nature-like algaecides of a new generation. PASS predictions were successfully compared to the available information on the biological activity of those compounds and confirmed experimentally. The present study shows that some organic acids significantly inhibit the growth of Synechocystis aquatilis Sauvageau and Aphanizomenon flos-aquae Ralfs ex Bornet and Flahault and can be used as algaecides for suppression of cyanobacteria. The inhibitory effect of the combined mixture of these allelochemicals is stronger than the effect of each individual component, suggesting that there are various mechanisms of cyanobacterial growth inhibitionПроблема борьбы с опасными цианобактериальными «цветениями» посредством разработки нового поколения альгицидов, основанных на аллелохемиках растений, актуальна на современной стадии развития водной экологии и биотехнологии. Статья посвящена использованию информационной технологии SAR (cвязь структура – активность) для выявления эффективных аллелохемиков водных макрофитов (с плавающими листьями – Nuphar lutea (L.) Sm., и нескольких видов погруженных макрофитов: Ceratophyllum demersum L., Myriophyllum spicatum L., Elodea canadensis Michx и виды рода Potamogeton) против планктонных цианобактерий. Обнаружение и идентификацию соединений проводили с использованием метода газовой хромато-масс- спектрометрии. Компьютерная программа PASS (прогнозирование спектров активности для веществ) была применена для прогнозирования спектров биологической активности мажорных компонентов метаболома макрофитов, чтобы обнаружить их экологический потенциал против цианобактерий. Изучение биологической активности основных низкомолекулярных органических соединений показало, что монокарбоновые кислоты, галловая кислота, цис‑6-октадеценовая кислота, цис‑9-октадеценовая кислота, пальмитолеиновая кислота, линоленовая кислота и 9-цис‑12- цис-линолевая кислота являются наиболее перспективными соединениями для экспериментальной проверки и создания природоподобных альгицидов нового поколения. Прогнозные оценки PASS были успешно сопоставлены с доступной информацией о биологической активности этих соединений, а также подтверждены экспериментально. Было показано, что некоторые жирные кислоты значительно ингибировали рост Synechocystis aquatilis Sauvageau и Aphanizomenon flos-aque Ralfs ex Bornet and Flahault и могут использоваться в качестве альгицидов для подавления цианобактерий. Поскольку ингибирующий эффект комбинированной смеси аллелохемиков был сильнее, чем у отдельных компонентов, имеются основания предполагать, что существуют различные механизмы ингибирования роста цианобактери

Gas Chromatography-Mass Spectrometric Study of Low-Molecular-Weight Exogenous Metabolites of Algae-Bacterial Communities in the Laboratory Accumulative Culture

The study of exogenous metabolites of algae-bacterial communities in the laboratory accumulative culture obtained from natural river water was conducted using gas chromatography-mass spectrometry. Exometabolites of the algae-bacterial community (including microalgae and cyanobacteria) in the culture medium were represented by saturated, unsaturated, and aromatic hydrocarbons, carboxylic acids, phenolic, and terpene compounds and their derivatives. Possible biological activities of the discovered exometabolites are considered. The study has demonstrated that an increase in the number of main groups of microorganisms, along with changes in the composition of algae and cyanobacteria, are responsible for the increase in the composition and concentration of metabolites in the microecosystem’s culture medium after one month of cultivation. The presence of octacosane in high concentration (0.0603 mg/L; 23.78% of the total content of low molecular weight organic compounds) by the end of exposure accumulative culture is associated with the strong development of the cyanobacterium Gloeocapsa sp. in the presence of diatom algae of the genus Navicula and green algae of the genera Chlorella and Scenedesmus. Due to the need to comprehend the ecological and biochemical mechanisms of the formation and functioning of algae-bacterial communities, as well as to predict potential paths of transformation and evolution of aquatic ecosystems, the specificity of exometabolite complexes of algae and microorganisms, as well as their allelopathic and other biochemical interactions in freshwater ecosystems, requires further serious study

Measurement of the sum of WW and WZ production with W+dijet events in pp collisions at sqrt(s) = 7 TeV

A measurement of the inclusive WW+WZ diboson production cross section in proton-proton collisions is reported, based on events containing a leptonically decaying W boson and exactly two jets. The data sample, collected at sqrt(s) = 7 TeV with the CMS detector at the LHC, corresponds to an integrated luminosity of 5.0 inverse femtobarns. The measured value of the sum of the inclusive WW and WZ cross sections is sigma(pp to WW+WZ) = 68.9 +/- 8.7 (stat.) +/- 9.7 (syst.) +/- 1.5 (lum.) pb, consistent with the standard model prediction of 65.6 +/- 2.2 pb. This is the first measurement of WW+WZ production in pp collisions using this signature. No evidence for anomalous triple gauge couplings is found and upper limits are set on their magnitudes