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Akashdeep Singh Oberoi, Ligy Philip
In the present study, an attempt was made to understand the variation in the toxicity during the biodegradation of aromatic hydrocarbons in single and multi-substrate system. The bacterial bioassay based on the inhibition of dehydrogenase enzyme activity of two different bacterial sp. E.coli and Pseudomonas fluorescens was used for toxicity assessment. Amongst the chosen pollutants, the highest acute toxicity was observed for benzothiophene followed by benzofuran having EC50 value of 16.60mg/L and 19.30mg/L respectively...
October 19, 2016: Ecotoxicology and Environmental Safety
J E Correia, C A Christofoletti, A C C Marcato, J F U Marinho, C S Fontanetti
Sugarcane vinasse is one of the main residues generated by the transformation of cane into ethanol. Because of the high organic content (COD), high biochemical oxygen demand (BOD), low pH, the large amount that this residue is generated (15l for every liter of ethanol produced) and their use as fertilizer on the sugarcane crop, this residue is potentially polluting to the soil ecossystem and by percolation to water ecossystem too. Thus, this study aimed to assess the toxicity of vinasse by analyzing Oreochromis niloticus gills exposed to different dilutions (1%, 2...
October 19, 2016: Ecotoxicology and Environmental Safety
Hans-Uwe Dahms, Eun-Ji Won, Hui-Su Kim, Jeonghoon Han, Heum Gi Park, Sami Souissi, Sheikh Raisuddin, Jae-Seong Lee
Aquatic invertebrates contribute significantly to environmental impact assessment of contaminants in aquatic ecosystems. Much effort has been made to identify viable and ecologically relevant invertebrate test organisms to meet rigorous regulatory requirements. Copepods, which are ecologically important and widely distributed in aquatic organisms, offer a huge opportunity as test organisms for aquatic toxicity testing. They have a major role not only in the transfer of energy in aquatic food chains, but also as a medium of transfer of aquatic pollutants across the tropic levels...
October 14, 2016: Aquatic Toxicology
Guaraci D Cordeiro, Mardiore Pinheiro, Stefan Dötterl, Isabel Alves-Dos-Santos
Bees are the most important diurnal pollinators of angiosperms. In several groups of bees a nocturnal/crepuscular habit was developed, yet, little is known about their role in pollination and whether some plants are adapted specifically to these bees. We used a multidisciplinary approach to investigate the reproductive biology and to understand the role of nocturnal/crepuscular bees in pollination of Campomanesia phaea (Myrtaceae), popularly named cambuci. We studied the floral biology and the breeding system of C...
October 22, 2016: Plant Biology
Kaouther Majouli, Assia Hamdi, Kamel Msaada, Abderraouf Kenani
This study was carried out with the objective to investigate the antibacterial activity of Hertia cheirifolia L. extracts against Gram-positive and Gram-negative strains including Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633), Bacillus licheniformis, Esherichia coli (ATCC 8739), Pseudomonas aeruginosa (ATCC 9027), Salmonella enterica (CIP 8039) and Salmonella typhimirium. The results of this antibacterial screening showed that the ethyl acetate (EtOAc) extracts had the best activity against the tested microorganisms...
October 18, 2016: Microbial Pathogenesis
Chandrashekhar Patil, Rahul Suryawanshi, Sunil Koli, Satish Patil
Aminocyclopropane-1-carboxylate deaminase (ACCD) producing microorganisms support plant growth under a variety of biotic and abiotic stress conditions such as drought, soil salinity, flooding, heavy metal pollution and phyto-pathogen attack. Available screening methods for ACCD give idea only about its primary microbial ACCD activity than the actual potential. In the present investigation, we have simply improved screening method by incorporating pH indicator dyes (phenol red and bromothymol blue) in ACC containing medium...
October 18, 2016: Journal of Microbiological Methods
Xing-Hai Liu, Wen Zhao, Zhong-Hua Shen, Jia-Hua Xing, Tian-Ming Xu, Wei-Li Peng
A series of novel difluoromethylpyrazole carboxamides derivatives were synthesized by introduction of flexible alkyl chain. Nematicidal bioassay results showed that some of them exhibited good control efficacy against M. incognita, which indicated that these difluoromethylpyrazole carboxamides derivatives might be potential novel lead compounds for discovery new nematicides. The nematicidal activity was affected by the substituted position in the molecule, especially the substitution group on the alkyl chain...
October 10, 2016: European Journal of Medicinal Chemistry
Jochem Louisse, Karsten Beekmann, Ivonne Magdalena Catharina Maria Rietjens
The development of reliable non-animal based testing strategies, such as in vitro bioassays, is the holy grail in current human safety testing of chemicals. However, the use of in vitro toxicity data in risk assessment is not straightforward. One of the main issues is that concentration-response curves from in vitro models need to be converted to in vivo dose-response curves. These dose-response curves are needed in toxicological risk assessment to obtain a point of departure to determine safe exposure levels for humans...
October 21, 2016: Chemical Research in Toxicology
Maryam Jamshidi-Aidji, Gertrud Elisabeth Morlock
Phytochemicals are promising agents in the development of new antibiotics. A streamlined strategy for rapid screening and reliable characterization of antibiotics in botanicals was demonstrated in contrast to the commonly applied chromatographic column fractionation followed by microtiter plate assay. Modern direct bioautography hyphenated to structure elucidation techniques is a straightforward bioanalytical tool, especially if microbiological assays were taken into account. At one go, lipophilic antimicrobials in Salvia miltiorrhiza root samples were analyzed using high-performance thin-layer chromatography (HPTLC) in direct combination with Aliivibrio fischeri and Bacillus subtilis bioassays...
October 21, 2016: Analytical Chemistry
Hajime Suzuki, Takahiro Sakabe, Yuu Hirose, Toshihiko Eki
We aimed to develop the bioassays for genotixicity and/or oxidative damage using the recombinant yeast. A genotoxicity assay was developed using recombinant Saccharomyces cerevisiae strain BY4741 with a green fluorescent protein (GFP) reporter plasmid, driven by the DNA damage-responsive RNR3 promoter. Enhanced fluorescence induction was observed in DNA repair-deficient strains treated with methyl methanesulfonate, but not with hydrogen peroxide. A GFP reporter yeast strain driven by the oxidative stress-responsive TRX2 promoter was newly developed to assess oxidative damage, but fluorescence was poorly induced by oxidants...
October 21, 2016: Applied Microbiology and Biotechnology
Lucía N Biruk, Juan Moretton, Alicia Fabrizio de Iorio, Cristian Weigandt, Jimena Etcheverry, Javier Filippetto, Anahí Magdaleno
The aim of this study was to investigate the parameters of chemical extraction associated with the detection of toxicity and genotoxicity in sediment sample extracts. Quantitative analysis of metals and polycyclic aromatic hydrocarbons (PAHs), together with a battery of four bioassays, was performed in order to evaluate the extraction efficiency of inorganic and organic toxicants. The extracts were carried out using two inorganic solvents, two organic solvents and two extraction methodologies, making a total of five extracts...
October 17, 2016: Ecotoxicology and Environmental Safety
Alemayehu Teressa Negawo, Linda Baranek, Hans-Jörg Jacobsen, Fathi Hassan
Transgenic pea lines transformed with the cry1Ac gene were characterized at molecular (PCR, RT-PCR, qRT-PCR and immunostrip assay) and functional levels (leaf paint and insect feeding bioassays). The results showed the presence, expression, inheritance and functionality of the introduced transgene at different progeny levels. Variation in the expression of the cry1Ac gene was observed among the different transgenic lines. In the insect bioassay studies using the larvae of Heliothis virescens, both larval survival and plant damage were highly affected on the different transgenic plants...
October 20, 2016: GM Crops & Food
Lavanya Kakarla, Suresh Babu Katragadda, Ashok K Tiwari, K Srigiridhar Kotamraju, K Madhusudana, D Anand Kumar, Mahendran Botlagunta
BACKGROUND: Cyperus scariosus R. Br and Cyperus rotundus L are widely used in ayurvedic preparation for the treatment of diabetes and other diseases. The early literature, so far, does not indicate the presence of any bioactive principle isolated from these plants. OBJECTIVE: To identify free radical scavenging, anti-diabetic and anti- inflammatory principles from these two species. MATERIALS AND METHODS: The bioassay guided fractionation and isolation of active constituents was done by chromatographic techniques...
July 2016: Pharmacognosy Magazine
Rebecca A Schmidt-Jeffris, Brian A Nault
Many vegetable insect pests are managed using neonicotinoid and pyrethroid insecticides. Unfortunately, these insecticides are toxic to many bees and natural enemies and no longer control some pests that have developed resistance. Anthranilic diamide insecticides provide systemic control of many herbivorous arthropod pests, but exhibit low toxicity to beneficial arthropods and mammals, and may be a promising alternative to neonicotinoids and pyrethroids. Anthranilic diamides may be delivered to vegetable crops via seed, in-furrow, or foliar treatments; therefore, it would be desirable to identify which application method provides high levels of pest control while minimizing the amount of active ingredient...
October 19, 2016: Journal of Economic Entomology
Gillian Hertlein, Marlene Seiffert, Sebastian Gensel, Eva Garcia-Gonzalez, Julia Ebeling, Ranko Skobalj, Anja Kuthning, Roderich D Süssmuth, Elke Genersch
The Gram-positive bacterium Paenibacillus larvae (P. larvae) is the causative agent of a deadly honey bee brood disease called American Foulbrood (AFB). AFB is a notifiable epizootic in most countries and, hence, P. larvae is of considerable relevance for veterinarians and apiculturists alike. Over the last decade, much progress has been made in the understanding of the (patho)biology of P. larvae. Recently, several non-ribosomally produced peptides (NRP) and peptide/polyketide (NRP/PK) hybrids produced by P...
2016: PloS One
A Sobrino-Figueroa
The toxic effects of four powder detergents: two laundry detergents (A and B), one household detergent (C), one dishwashing detergent (D), and the surfactant alkylbenzene sulfonate (LAS) were analyzed in this study on organisms from different trophic levels (microalgae, cladocerans, ostracods, amphipods, macrophytes, and fish). LC50 and EC50 values obtained in the toxicity bioassays varied between 0.019 and 116.9 mg L(-1). The sensitivity of the organisms to the detergents was (from most sensitive to least sensitive) Ostracods > microalgae > amphipods > cladocerans > fishes > macrophytes...
October 18, 2016: Environmental Science and Pollution Research International
Stefan C Weiss, Nicole Egetenmeyer, Wolfgang Schulz
Modern analytical test methods increasingly detect anthropogenic organic substances and their transformation products in water samples and in the environment. The presence of these compounds might pose a risk to the aquatic environment. To determine a possible (eco)toxicological risk, aquatic samples are tested using various bioassays, including sub-organismic assays such as the luminescent bacteria inhibition test, the acetylcholinesterase inhibition test, and the umu-test. The effect-directed analysis (EDA) combines physicochemical separation methods with biological (in vitro) tests...
October 19, 2016: Advances in Biochemical Engineering/biotechnology
Yoshiaki Manse, Kiyofumi Ninomiya, Ryosuke Nishi, Iyori Kamei, Yushi Katsuyama, Takahito Imagawa, Saowanee Chaipech, Osamu Muraoka, Toshio Morikawa
An aqueous acetone extract from the fruit of Alpinia galanga (Zingiberaceae) demonstrated inhibitory effects on melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells (IC50=7.3μg/mL). Through bioassay-guided separation of the extract, a new 7-O-9'-linked neolignan, named galanganol D diacetate (1), was isolated along with 16 known compounds including 14 phenylpropanoids (2-15). The structure of 1, including its absolute stereochemistry in the C-7 position, was elucidated by means of extensive NMR analysis and total synthesis...
October 6, 2016: Bioorganic & Medicinal Chemistry
Narayan D Chaurasiya, Vedanjali Gogineni, Khaled M Elokely, Francisco León, Marvin J Núñez, Michael L Klein, Larry A Walker, Stephen J Cutler, Babu L Tekwani
Calea urticifolia (Asteraceae: Asteroideae) has long been used as a traditional medicine in El Salvador to treat arthritis and fever, among other illnesses. The chloroform extract of the leaves of C. urticifolia showed potent inhibition of recombinant human monoamine oxidases (MAO-A and -B). Further bioassay-guided fractionation led to the isolation of a flavonoid, acacetin, as the most prominent MAO inhibitory constituent, with IC50 values of 121 and 49 nM for MAO-A and -B, respectively. The potency of MAO inhibition by acacetin was >5-fold higher for MAO-A (0...
October 18, 2016: Journal of Natural Products
J C Vidal-Quist, F Ortego, B N Lambrecht, P Castañera, P Hernández-Crespo
The expression of allergen genes in house dust mites is influenced by temperature and relative humidity, but little is known of the impacts of other environmental factors that may alter the repertoire of allergens released by mites in home microhabitats. Bioassays were conducted in concave microscope slides in combination with real-time quantitative polymerase chain reaction (RT-qPCR) to analyse gene expression of 17 allergens of Dermatophagoides pteronyssinus (Acariformes: Pyroglyphidae) exposed to three chemical stressors that can be present in domestic environments...
October 18, 2016: Medical and Veterinary Entomology
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