Isolation and characterization of chitinase from soil fungi, Paecilomyces sp.

AbstractChitinolytic fungal strains were isolated from soil in Thailand. They were screened as chitinase producers by testing their shrimp shell digestion ability on potato dextrose agar plates. The chitinase activity was tested with colloidal chitin in culture medium C and basal medium. There was greater activity in culture medium C than in the basal medium. The results of sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis from the culture filtrate of medium C showed three protein bands at about 40 kDa, 46 kDa and 56 kDa. The chitinase gene was sequenced from genomic DNA. The obtained sequence consisted of 713 bp upstream, a 1499 bp open reading frame that was interrupted by three introns and 1698 bp downstream sequences. The intron lengths were 63 bp, 57 bp and 110 bp, respectively. The sequence was found to be the most similar to the chitinase gene of Paecilomyces lilacinus (EF183511). Pairwise alignment of the 1499 bp and P. lilacinus resulted in 72.5% DNA sequence identity, while alignment of the 1269 bp coding sequence and P. lilacinus resulted in 78.5% cDNA sequence identity and 83.5% amino acid sequence identity. The protein structure contained two conserved domains of the putative substrate binding site (S-I-G-G) and catalytic domain (D-G-I-D-L-D-W-E), suggesting that this fungal chitinase belonged to the glycosyl hydrolases family 18 chitinase (GH18). Phylogenetic analysis of the chitinase gene from the nematopathogenic fungi suggested that this chitinase sequence was class V chitinase

การศึกษารูปแบบการเรียนรู้ของนักศึกษาระดับปริญญาตรี มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าพระนครเหนือ

The objective of this research is firstly to study the teaching and learning process of senior or fourth-year undergraduate students in academic year 2012 and secondly to examine the difference in learning patterns. Lastly, the purpose is to compare the learning patterns categorized by the field of study. This research methodology applied a random sampling method by selecting the sample from the final year undergraduate student who is studying in 4 to 5 years course and 2 to 3 years course in King Mongkut’s University of Technology North Bangkok. The 1,516 selecting samples were implemented from totally 5,185 students by using the questionnaire as a tool to obtain the data and to analyze the learning patterns. The research questionnaire consists of 40 questions based on 5 forms of the process skills in teaching and learning patterns by dividing question into 2 groups, 20 questions for university’s identity consistently and others for university’s identity inconsistently. The result is found that the learning pattern of students which is corresponding to the identity has an overall average equal to 3.66 which indicated as high level. And the average of pattern which is not corresponding to identity is estimated to be 3.19 or moderate level. However, by comparison the results between each faculty, it demonstrated that there are not different much in learning pattern. Therefore, this research can be helpful for university’s administrators by considering these aspects into university’s policy and bring to the decision management plans in order to gain the optimal teaching process. Furthermore, by conducting the process of this research can help the lecturers and teaching staffs to know and integrate the student’s opinion for improvement the teaching plan appropriately and response to the learning styles of student and university’s identity. In conclusion, the lecturers and teaching staffs will be able to integrate the ideas and develop the learning process of most students coherently

Delay Factors between Main Contractors and Nominated Subcontractors in High Rise Buildings in Thailand

This research is a study of factors affecting the delay of the construction period by working together during construction between main contractors and nominated sub-contractors in high rise building at Bangkok and vicinity. The focus of factors which cause delays to the structural works, architectural work, electrical - mechanical works and sanitation work in General Contract (Dominated –Sub-contract) and Nominated Sub-contract. This study used questionnaires and interviews as tool for collecting data. Data analysis methods to compare average frequency in order to know the factors that make each type of construction delays and statistical methods Independent-Sample t-test to find out the critical factors to the construction both of the contrast delay. The results showed that factors which cause delays affecting the construction period consisted of not working together as team-work, project management experience is not enough and be deficient in skill of communicate and coordinate. It also found that the delay factor of five critical factors that make construction in terms of structure, architecture, electrical-mechanical and sanitation was always delayed. Factors include delays resulting from not working together as team work, period of plan laid down, delayed delivery area, delays in approval and construction item and shortage of skilled labor, or labor shortages during the season so aware of critical factors that delay the construction above. And find ways to prevent construction delays caused by these factors

Biological control of turfgrass diseases with organic composts enriched with Trichoderma atroviride

The increasing demand of natural products for the control of plant diseases has led to the search for biological control agents, namely fungi, often isolated from composts of organic residues. By composting two different mixes of agro-industrial residues, P1 and P2 composts were obtained, from where a known antagonist, Trichoderma atroviride, was isolated. Later, a second composting process was performed and when the composting mix reached room temperature, the previously isolated T. atroviride was inoculated in both composts to enrich its population (E) and named as P1E and P2E. The suppressive capacity of these two composts against Sclerotium rolfsii, Clarireedia spp. and Rhizoctonia solani was tested two weeks after T. atroviride inoculation, in 100 mL pots with turfgrass seeded with Agrostis stolonifera. The tested treatments were: composts P1 and P2 without any treatment; thermally treated P1 and P2 (P1t, P2t); P1 and P2 enriched without and with previous thermic treatment (P1E, P2E, P1tE, P2tE), and a commercial peat-based substrate, natural (P) and thermally treated (Pt), enriched (PE) and enriched after thermal treatment (PtE). Enriched composts achieved the highest disease control. P1E was more effective in controlling Clarireedia spp.; pots with infected plants grown on P1E, showed 53.5% less affected area compared to P1t. P2E was more effective against R. solani; results showed 69.3% less affected area compared to P2t and both were effective in S. rolfsii control, with a reduction of 38.5% in P1E and 43.5% in P2E. The larger population of Trichoderma spp. observed in the enriched substrates associated to the greater enzyme activity, namely and N-acetyl-β-glucosaminidase, standing out in P2E, will have contributed strongly to the biocontrol of the studied diseases. An increase in some macro and micronutrients was observed in the enriched heat-treated substrates.FCT: SFRH/BD/109218/2015info:eu-repo/semantics/publishedVersio