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61.
Characterization of a fungal strain capable of degrading chlorpyrifos and
its use in detoxification of the insecticide on vegetables 总被引:2,自引:0,他引:2
A fungal strain capable of utilizing chlorpyrifos as sole carbon and energy sources was isolated from soil by enrichment cultivation approach. The half-lives of degradation (DT50) for chlorpyrifos at concentrations of 1, 10, and 100 mg l−1 by the fungal strain DSP in mineral salt medium were measured to be 2.03, 2.93, and 3.49 days, respectively. Two cell-free extracts [E (1:10) and E (1:20)] from the fungal strain DSP in bran–glucose medium were prepared and used to enhance chlorpyrifos degradation on vegetables. Compared with the controls, the DT50 of chlorpyrifos were reduced by 70.3%, 65.6%, 80.6%, 80.6%, and 86.1%, and by 53.8%, 43.2%, 66.0%, 54.3%, and 67.7% on E (1:20) and E (1:10) treated pakchoi, water spinach, Malabar spinach, haricot beans, and pepper, respectively. The 7-day residual values (R
7) of chlorpyrifos on E (1:10) treated vegetables were all lower than the corresponding maximum residue levels of European Union (EU MRLs), except that the R
7 value on haricot beans was slightly higher than the corresponding EU MRLs. The results indicate that cell-free extracts could rapidly degrade chlorpyrifos residues on vegetables. 相似文献
62.
A rapid clonal propagation system for Clerodendrum colebrookianum Walp. (Verbenaceae), a anti-hypertension folk medicinal shrub has been developed. A range of cytokinins has been investigated for multiple shoot induction with shoot apex, axillary shoot, leaf, petiole and root explants. Optimum shoot induction occurred with axillary buds using 6-benzyladenine where an average of 21 shoots were produced per explant in 6 weeks. Subculturing the newly produced shoots, by separating into groups of five shoots, produced an average of 43 new shoots per culture within 4 weeks. In vitro rooting and weaning of over 200 plantlets was completely successful. Cytological studies revealed no visible abnormalities in chromosome number.Abbreviations 2iP
2-isopentenyladenine
- BA
6-benzyladenine
- LSD
Least Significant Difference
- NAA
1-naphthaleneacetic acid
- TDZ
thidiazuron
- WPM
Woody Plant Medium (Lloyd & McCown 1980) basal medium 相似文献
63.
64.
Yanxin Gong Yuanqing Wang Yang Wang Fangyuan Mao Bin Bai Haibing Wang Qian Li Xun Jin Xu Wang Jin Meng 《Palaeontology》2020,63(4):547-564
Lophialetidae is an extinct group of endemic Asiatic tapiroids that are widely distributed in the Eocene sediments of Asia. Schlosseria magister and Lophialetes expeditus are the most abundant species in this family. However, their dietary and ecological characteristics are largely unknown. For the first time, we reconstruct the palaeodiet and habitat of these two lophialetids using a combination of mesowear and stable carbon isotope analysis of fossil teeth excavated from the Erlian Basin, China. Mesowear analysis (n = 141) suggests that the dietary structure of S. magister and L. expeditus shifted from less to more abrasive diets from ~52 to ~42 Ma. Stable carbon isotope analysis (n = 137) suggests that the habitats of S. magister and L. expeditus became drier and/or more open through time. The dietary shifts of the two lophialetids are consistent with evident changes in habitat. The changes in the diet and habitat were probably related to global climate change during that time period. The gradual drop in global temperatures during the early–middle Eocene led to a drier and more open terrestrial ecosystem in the Erlian Basin, probably resulting in changes in floral composition of the environment inhabited by S. magister and L. expeditus. Hence, herbivores highly susceptible to vegetation modification had to develop new resource exploitation strategies to adapt to these changes. Schlosseria magister, considered to be the sister-group of L. expeditus and with a low level of ecological flexibility, was unable to adapt to the habitat changes finally becoming extinct at ~45 Ma. 相似文献
65.
Dun-Feng Xu Yu-Jian Liu Yan-Fei Mao Yan Wang Chu-Fan Xu Xiao-Yan Zhu Lai Jiang 《Journal of cellular and molecular medicine》2021,25(8):4124-4135
Thrombocytopenia is independently related with increased mortality in severe septic patients. Renin-angiotensin system (RAS) is elevated in septic subjects; accumulating studies show that angiotensin II (Ang II) stimulate the intrinsic apoptosis pathway by promoting reactive oxygen species (ROS) production. However, the mechanisms underlying the relationship of platelet apoptosis and RAS system in sepsis have not been fully elucidated. The present study aimed to elucidate whether the RAS was involved in the pathogenesis of sepsis-associated thrombocytopenia and explore the underlying mechanisms. We found that elevated plasma Ang II was associated with decreased platelet count in both patients with sepsis and experimental animals exposed to lipopolysaccharide (LPS). Besides, Ang II treatment induced platelet apoptosis in a concentration-dependent manner in primary isolated platelets, which was blocked by angiotensin II type 1 receptor (AT1R) antagonist losartan, but not by angiotensin II type 2 receptor (AT2R) antagonist PD123319. Moreover, inhibiting AT1R by losartan attenuated LPS-induced platelet apoptosis and alleviated sepsis-associated thrombocytopenia. Furthermore, Ang II treatment induced oxidative stress level in a concentration-dependent manner in primary isolated platelets, which was partially reversed by the AT1R antagonist losartan. The present study demonstrated that elevated Ang II directly stimulated platelet apoptosis through promoting oxidative stress in an AT1R-dependent manner in sepsis-associated thrombocytopenia. The results would helpful for understanding the role of RAS system in sepsis-associated thrombocytopenia. 相似文献
66.
67.
Jia-Liang Li Lin-Ling Zhong Jing Wang Tao Ma Kang-Shan Mao Lei Zhang 《植物分类学报:英文版》2021,59(6):1220-1231
Natural selection serves as an important agent to drive and maintain interspecific divergence. Populus rotundifolia Griff. is an alpine aspen species that mainly occurs in the Qinghai–Tibet Plateau (QTP) and adjacent highlands, whereas its sister species, P. davidiana Dode, is distributed across southwest and central to northeast China in much lower altitude regions. In this study, we collected genome resequencing data of 53 P. rotundifolia and 42 P. davidiana individuals across their natural distribution regions. Our population genomic data suggest that the two species are well delimitated in the allopatric regions, but with hybrid zones in their adjacent region in the eastern QTP. Coalescent simulations suggest that P. rotundifolia diverged from P. davidiana in the middle Pleistocene with following continuous gene flow since divergence. In addition, we found numerous highly diverged genes with outlier signatures that are likely associated with high-altitude adaptation of these alpine aspens. Our finding indicate that Quaternary climatic changes and natural selection have greatly contributed to the origin and distinction maintenance of P. rotundifolia in the QTP. 相似文献
68.
69.
70.
Sato Nana Yuzawa Mao Aminul Md Islam Tomokiyo Mikado Albarracin Leonardo Garcia-Castillo Valeria Ideka-Ohtsubo Wakako Iwabuchi Noriyuki Xiao Jin-zhong Garcia-Cancino Apolinaria Villena Julio Kitazawa Haruki 《Probiotics and antimicrobial proteins》2021,13(3):824-836
Probiotics and Antimicrobial Proteins - The use of in vitro systems that allow efficient selection of probiotic candidates with immunomodulatory properties could significantly minimize the use of... 相似文献