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951.
Isolation of a soil bacterium capable of biodegradation and detoxification of endosulfan and endosulfan sulfate 总被引:2,自引:0,他引:2
Lee JB Sohn HY Shin KS Jo MS Kim JE Lee SW Shin JW Kum EJ Kwon GS 《Journal of agricultural and food chemistry》2006,54(23):8824-8828
Endosulfan, an endocrine disrupting chemical, is a widely used cyclodiene organochlorine pesticide worldwide, and it blocks neuronal GABA(A)-gated chloride channels in mammals and aquatic organisms. Endosulfan and its metabolites, such as endosulfan sulfate, are persistent in environments and are considered as toxic chemicals. For bioremediation of endosulfan, in this study, an attempt was made to isolate an endosulfan and endosulfan sulfate degrading bacterium from endosulfan-polluted agricultural soil. Through repetitive enrichment and successive subculture using endosulfan or endosulfan sulfate as the sole carbon source, a bacterium KS-2P was isolated. The KS-2P was identified as Pseudomonas sp. on the basis of the results of a 16S rDNA sequencing analysis and MIDI test. The degradation ratios for endosulfan or endosulfan sulfate in minimal medium containing endosulfan (23.5 microg mL(-1)) or endosulfan sulfate (21 microg mL(-1)) were 52% and 71%, respectively. Our results suggest that Pseudomonas sp. KS-2P has potential as a biocatalyst for endosulfan bioremediation. 相似文献
952.
Watts AE Fubini SL Vernier-Singer M Golkowski C Shin S Todhunter RJ 《American journal of veterinary research》2006,67(12):2030-2035
OBJECTIVE: To determine the effect of nonthermal plasma on Staphylococcus aureus, fibroblasts in monolayer culture, and clean and contaminated skin explants. SAMPLE POPULATION: Normal skin from euthanized horses. PROCEDURES: S aureus organisms were plated and treated with nonthermal plasma followed by bacterial culture to assess viability. Fibroblasts in monolayer culture and the epidermal and dermal surfaces of clean and S aureus-contaminated skin explants were treated. The effects of distance and duration on the response to treatment were compared. RESULTS: Compared with controls, treatment with nonthermal plasma resulted in significantly decreased bacterial growth and significantly inhibited survival of fibroblasts in monolayer culture. When epidermal and dermal surfaces of skin explants were treated, there was no effect on production of normal fibroblasts during explant culture, except when extended exposure times of >or= 2 minutes were used. Treatment with nonthermal plasma resulted in significantly lower bacterial counts after 24 hours of culture of S aureus-contaminated epidermis but not of dermis. CONCLUSIONS AND CLINICAL RELEVANCE: Nonthermal plasma resulted in bacterial decontamination of agar and epithelium; negative effects on fibroblasts in monolayer; and no negative effects on skin explants, except at long exposure times. Use of nonthermal plasma appears safe for treatment of epithelialized surfaces, may be safe for granulating wounds, and results in decontamination of S aureus. Investigations on the effects that nonthermal plasma may have on patient tissues are indicated with a clinically applicable delivery device. 相似文献
953.
Jae‐Bom Ohm Gary Hareland Senay Simsek Bradford Seabourn Elizabeth Maghirang Floyd Dowell 《Cereal Chemistry》2010,87(6):553-560
Molecular weight distribution (MWD) of proteins extracted from hard red spring wheat was analyzed by size‐exclusion HPLC to investigate associations with wheat and breadmaking quality characteristics. Certain protein fractions were related to associations between wheat and breadmaking parameters, specifically when effect of quantitative variation of protein on those parameters was statistically eliminated by partial correlation analysis. SDS‐unextractable high molecular weight polymeric proteins had positive partial correlations with percent vitreous kernel content and breadmaking parameters, including mix time and bread loaf volume. SDS‐extractable protein fractions that were eluted before the primary gliadin peak had positive partial correlations with kernel hardness and water absorption parameters. The proportion of main gliadin fractions in total protein had a negative partial correlation with bread loaf volume and positive correlations with kernel hardness and water absorption parameters. Intrasample uniformity in protein MWD and kernel characteristics was estimated from three kernel subsamples that were separated according to single kernel protein content within individual wheat samples by a single‐kernel near‐infrared sorter. Wheat subsamples were significantly different in protein MWD. Intrasample uniformity in protein MWD did not differ greatly among wheat samples. 相似文献
954.
Inhibitory effects of Orostachys japonicus extracts on the formation of N-nitrosodimethylamine 总被引:1,自引:0,他引:1
Choi SY Chung MJ Seo WD Shin JH Shon MY Sung NJ 《Journal of agricultural and food chemistry》2006,54(16):6075-6078
In Korea, Orostachys japonicus has been used traditionally as a drug and health food. The aim of this study was to investigate possible inhibitory effects of O. japonicus extracts on the formation of N-nitrosodimethylamines (NDMA). Chloroform extraction was the most effective method for recovering the highest number of phenolic compounds and flavonoids; in these extracts the greatest nitrite-scavenging activity and inhibition of NDMA formation occurred at pH 2.5. The chloroform extract was separated into 10 fractions (J1-J10); fraction J4 inhibited NDMA formation by 90.1 +/- 0.4%. This fraction was then separated into five subfractions (J4-1-J4-5) using a silica gel column. Subfractions J4-2 [(+)-catechin] and J4-4 (3,4-dihdroxybenzoic acid) inhibited NDMA formation by 89.5 +/- 0.9 and 77.6 +/- 0.8%, respectively. 相似文献
955.
Lee Chorong Kim Soohwan Shin Jaehyeong Kim Min-Gi Gunathilaka Buddhi E. Kim Sung Hun Kim Ji Eun Ji Seung-Cheol Han Jee Eun Lee Kyeong-Jun 《Aquaculture International》2021,29(6):2463-2475
Aquaculture International - This study was conducted to evaluate the dietary supplementation of two Bacillus spp. on digestibility, growth performance, innate immunity, and water ammonia level of... 相似文献
956.
San San Yi Yukari Akashi Katsunori Tanaka Tin Tin Cho May Thin Khaing Hiromichi Yoshino Hidetaka Nishida Tatsuya Yamamoto Kyaw Win Kenji Kato 《Genetic Resources and Crop Evolution》2009,56(8):1149-1161
Genetic diversity of Myanmar melon was evaluated by analysis of 27 RAPD markers and morphological characters using 41 accessions
of melon landraces of which 36 accessions were small-seed type. The gene diversity was 0.239, higher than for group Conomon
from East Asia and equivalent to Indian melon populations. Melon accessions were classified into six major clusters. The largest
cluster IV comprised mainly group Conomon which was closely related to cluster V consisting of mainly group Agrestis. Most
of the accessions of group Cantalupensis were grouped into clusters II or VII and were distantly related to groups Conomon
and Agrestis. The genetic relationship to melon accessions from neighboring countries was analyzed. The 24 accessions of clusters
IV and V were mostly clustered together with small-seed type melon of India, but the 14 accessions of clusters VI and VII
were mostly clustered together with large-seed type melon of India. These results indicated that the genetic diversity of
Indian melon is conserved in Myanmar. Genetic introgression among melon groups through spontaneous hybridization was also
indicated and was considered important to maintain or increase the genetic diversity in Myanmar. 相似文献
957.
The brown marmorated stink bug. Halyomorpha halys, (BMSB) is an exotic pest causing damage to fruits and vegetables. They also transmit diseases. Integrated pest management strategies are lacking for this invasive. For the first time, information is presented on the virulence of several entomopathogenic fungi against BMSB. Three Beauveria bassiana and two Metarhizium anispoliae isolates were bioassayed against adult BMSB. One B. bassiana isolate was the active ingredient in BotaniGard® which produced 85 and 100% mortality in 9 and 12 days post treatment, respectively. Experimental isolates ERL 1170 and ERL 1540 were also efficacious. Metarhizium anispoliae isolates produced lower mortalities than the B. bassiana isolates. Data presented showed the potential for management of BMSB with entomopathogenic fungi. Copyright © 2012 Society of Chemical Industry 相似文献
958.
BACKGROUND: The relationship between the particle size of spray‐dried Bacillus thuringiensis NT0423 technical powder and its insecticidal activity against diamondback moth was investigated in laboratory and glasshouse conditions. A variety of sizes of Bt particles were made by homogenisation, followed by pilot‐scale milling to optimise further the current Bt formulation process. RESULTS: In laboratory conditions, homogenised Bt suspension with smaller particles had higher control efficacy against diamondback moth. However, in glasshouse conditions, the smallest particle treatment did not follow the size‐dependent insecticidal activity, rather showing decreased control efficacy. Secondly, air‐jet‐milled Bt powder (16.9 µm) had higher control efficacy than hammer‐milled Bt powder (35.1 µm) in glasshouse conditions. However, double air‐jet milling (5.3 µm) had lower control efficacy compared with one‐time milling. CONCLUSION: These results suggest that NT0423 technical powder with smaller particles is better in controlling diamondback moths, but excessively small particles (<10 µm) possibly reduce the insecticidal activity. Copyright © 2012 Society of Chemical Industry 相似文献
959.
Ana Alfaro-Fernández Mai Abdalla Ali Fadia Mobarak Abdelraheem Ebrahim Abd Elhameed Saeed María Isabel Font San Ambrosio 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(4):791-795
In January 2011, symptomatic chickpea and faba bean plants were observed in fields located in the Gezira state (Sudan). Faba bean plants showed yellowing and stunting, whereas chickpea plants presented yellowing, reddening and little leaves. The disease etiology was investigated using nested polymerase chain reaction (PCR) with phytoplasma-specific primers which amplify a fragment of the 16S rRNA gene. Sequencing and restriction fragment length polymorphism (RFLP) analyses revealed that the tested phytoplasmas belonged to the group 16SrII. Phylogenetic analyses of the 16S rRNA gene of the obtained sequences indicated that the chickpea and faba bean phytoplasmas from Sudan were more closely related to the phytoplasmas subgroup 16SrII-D. To our knowledge, this is the first report of phytoplasmas from the group 16SrII-D infecting chickpea in Sudan, and faba bean worldwide. 相似文献
960.
Mohamed Tharwat Aya Takamizawa Yoshinao Z. Hosaka Daiji Endoh Shin Oikawa 《Canadian journal of veterinary research》2012,76(4):241-247
The objective of this study was to investigate hepatocyte apoptosis in dairy cows during the transition period. Four clinically healthy, pregnant dairy cattle were used. The cows had no clinical diseases throughout this study. Blood samples were collected and livers were biopsied from the cows at 3 different times: 3 weeks before expected partition (wk −3); during parturition (wk 0), and 3 weeks (wk +3) after parturition. The damage to deoxyribonucleic acid (DNA) caused by hepatocytes was evaluated by comet assay. The apoptotic features of hepatocytes were examined by immunohistochemistry and electron microscopic analyses. The hepatic triglyceride content markedly increased at wk 0 and wk +3 compared with the values at wk −3. The results of the comet assay showed increases in the mean tail moment values of hepatic cells after parturition in all cows, which suggested increased DNA damage. Histopathologically, the hepatocytes began to contain lipid droplets at wk 0 and were severely opacified at wk +3. Caspase-3-positive and single-stranded DNA-(ssDNA)-positive cells were first detected in the liver after parturition. Condensation of nuclear chromatin, a typical sign of apoptosis, was confirmed by transmission electron microscopy after parturition. These results suggest that apoptosis is induced in hepatocytes of dairy cows around parturition and may result from lipotoxicity in hepatocytes. 相似文献