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Home > Isolation and Mutagenesis of a Bacterial Strain for Enhanced Production and Characterization of Organophosphate Hydrolase

Isolation and Mutagenesis of a Bacterial Strain for Enhanced Production and Characterization of Organophosphate Hydrolase

Thesis Info

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External Link

Author

Rasul, Samreen

Program

PhD

Institute

University of Agriculture

City

Faisalabad

Province

Punjab

Country

Pakistan

Thesis Completing Year

2015

Thesis Completion Status

Completed

Subject

Natural Sciences

Language

English

Link

http://prr.hec.gov.pk/jspui/handle/123456789/761

Added

2021-02-17 19:49:13

Modified

2024-03-24 20:25:49

ARI ID

1676726537729

Similar


Organophosphate pesticides are of common interest due to increased envionmenal contamination. Such agents cause several undesired and un-solved problems in non-target species. The enzyme organophosphate hydrolase (OPH) producing bacterial strain Brevibacillus parabrevis SR2729 (B. parabrevis SR2729) was isolated from soil contaminated with chlorpyrifos. Brevibacillus parabrevis SR2729 was subjected to strain improvement by physical and chemical mutagenesis; where two strains B. parabrevis SR2729-A and B. parabrevis SR2729-B were selected after classical screening through Triton-x-100 and 3,5,6-trichloro-2-pyridinol. The mutant derived strains Brevibacillus parabrevis SR2729-A and Brevibacillus parabrevis SR2729-B showed 229 and 240 % greater OPH production as compared to parental strain. The optimum levels of six variables (pH, temperature, incubation time, carbon source, nitrogen source and pesticide concentration) were obtained after statistical analysis by RSM. After process optimization, the activities of OPH from B. parabrevis SR2729-A and B. parabrevis SR2729-B were 195 and 178 % greater than OPH from parental strain B. parabrevis SR2729. The specific activity for purified enzyme was observed to be 935, 1521 1911 U mg-1 from parental and mutant derived strains B. parabrevis SR2729-A and B. parabrevis SR2729-B, respectively. After kinetic and thermodynamic analysis, the enzyme from mutant derived strains was observed to be more suitable for utilizing chlorpyrifos as substrate, with higher thermostability as compared to the enzyme from parental strain. The molecular weight of OPH enzymes from parental and mutant derived strains were 37 kDa. In soil, the OPH from mutant derived strains B. parabrevis SR2729-A and B. parabrevis SR2729-B showed 206 and 208 % greater degradation of chlorpyrifos as compared to parental strain. The enzyme from mutant derived strains B. parabrevis SR2729-A and B. parabrevis SR2729-B degraded 28 and 65 % greater insecticide in water compared to enzyme from parental strain. In conclusion, the strain improvement by physical and chemical mutagenesis resulted in the selection of potential mutant derived strains which were more significant agents for the degradation of chlorpyrifos in soil and water samples.
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زندہ ہے بھٹو

زندہ ہے بھٹو

                                                                                                                رضا زیدی

سیدھی بات ہے جو موت کو ،امیر المومنین علی ؑ کی سنت پر دلیری سے عمل پیرا ہوتے ہوئے ۔کامیابی سمجھ کر گلے سے لگائے وہ بھٹو بن جا تا ہے ۔اس کی زندگی کا مذاق اڑانے یا جلنے والے جلتے جلتے مر جاتے ہیں ۔مٹ جاتے ہیں اور بھٹو گردشِ لیل و نہارکے ساتھ ساتھ اپنی زندگی ،اپنے وجود اور اپنی خوشبو محسوس کراتا رہتا ہے ۔۔۔۔زندہ ہے بھٹو جلنے والے دفع دور رہیں ۔

جب تک سورج رہے گا

بھٹو تیرا نام رہے گا

یہ شخص ایک شکست خوردہ ملک کا سربراہ تھا ۔سامنے والی خاتون فاتح تھی اور اس کی قید میں اس شخص کی نوے ہزار سپاہ تھی اور اس کی زمین کا خاطر خواہ حصہ اس خاتون کے قبضے میں تھا ۔پھر بھی اس شخص کے چہرے پر اعتماد اطمینان اور اس کی بدن بولی دیکھیے ۔ایک شکست خوردہ ملک کا صدر مذکرات کی میز پر وہ سب کچھ جیت گیا جو ہم ممیدانِ جنگ میں ہار چکے تھے ۔

 

Challenges of Translating the Arabic Qur’an into English A Comparative Study of Eight Leading Translations

Any translation of the Arabic Qur’an in English or any European language is likely to be imperfect. This is primarily due to the differences in the language, semantics, idiom, style and culture. Almost fifty such translations have appeared in the last fifty years, both by Muslim and other scholars, but none can claim any perfection in imaging the Arabic Qur’an. Nevertheless, there are some that are faithful to word-by-word (literal) or sense-for-sense (free) translation, but most lack the flavor of the Qur’anic essence and image either due to the translating approach, or inadequate understanding of the meaning of Sacred Arabic Text, or constraints of eloquence of the English language. This paper examines eight of the leading translations and draws conclusions relating to the use of translation techniques and literary devices and concepts that add beauty to the eloquence of Arabic Qur’an and makes it a living and literary masterpiece. It is found that the meaning of the lexical expressions have been maintained to a high degree in the process of translation and the use of literary devices has been adequately captured by the selected translations.

Factors Promoting Excellence in Schools

The study, “Factors Promoting Excellence in Schools” took cognizance of the pressing problem that there was widespread deterioration of education in Khyber Pakhtunkhwa Province of Pakistan. The stakeholders had many expectations from the secondary schools both in public (government) and private sectors. The parents also needed feedback and authentic information about the criteria of excellent schools. It was therefore considered imperative to identify factors that promoted excellence in schools on the basis of information obtained from review of global literature as well as the feedback provided by stakeholders in the form of their responses. The items included in the opinionnaires and interviews for principals, teachers, parents and students were mostly derived from the authentic sources that were studied. For the purpose of obtaining relevant information from participants items were mentioned under different categories such as school specific statements, school improvement strategies and the skills of effective principals. The population of the study included 247 principals/headmasters, 2964 teachers, 494 parents and more than 10,000 students of 10th class in total number of 247 boys’ high schools in Peshawar City including 27 schools in public (government) and 220 in private sector in Khyber Pakhtunkhwa province of Pakistan. The sample included 30 principals, 60 teachers, 600 students of 10th class and 60 parents. The primary data were collected through opinionnaires administrated to principals/headmasters, teachers and students, while closed-ended interviews were held with purposively selected parents. The results of Board of Intermediate and Secondary Education Peshawar for 10th class of the sampled schools for the last 03 years (2008-10) were also made part of secondary data. The data received both quantitative and qualitative treatment. The quantitative analysis applied statistical measures to some of the aspects of the collected data. The data were analyzed with the help of tables and graphs and rendered meaningful with discussion and interpretation. The qualitative data were placed under different patterns and categories for discussion. The outcome of the study indicated that excellence was multi-dimensional phenomenon and, therefore, many factors collectively contributed to effectiveness of school. The most important factors included relevant curricula, devoted and well trained teachers, co- curricular activities, effective principals, collegiality of teachers and the needed infrastructure. The interventional role of principals also made difference in school effectiveness. They could intervene in matters of instructional supervision, efficient administration, promoting collegiality of teachers, and including them in decision-making processes. The positive school-community relationships were also instrumental in school effectiveness. The study found that excellent schools had effective classroom interaction, stakeholders’ consideration that it was better school for teaching-learning and both teachers and students were proud of the effectiveness of their schools. The recommendations of the study were a set of general and specific factors developed on the basis of review of literature and responses of subjects of different categories. They included a focus on within and out of school factors such as leadership skills of principals, qualified and devoted teachers, better school environment and infrastructure as well as effective school-home relationships. The study answered all the four research questions that were posed in the study.