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Teaching and Research Lab

Written by hidayah. Posted in Research

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Isolation, characterization and identification of lipase producing bacteria and optimization of lipase production

Written by hidayah. Posted in Research

  • Researcher                      : Prof. Dr. Ibrahim Che Omar
  • Student                             : Sharlina Binti Mat Saad

Abstract

Samples were collected from different sources in palm oil mill factory located in Kulim, Kedah. Screening of lipase producing bacteria was done on Tributyrin agar plate and formation of zone of hydrolysis was observed. Total 18 isolates were characterized and identified based on morphological properties, colony characteristics and biochemical properties. Isolate HS6 was selected for its maximum yield of lipase (627 U/ml) and identified as Bacillus cereus via 16S rRNA analysis, a Gram positive bacilli. The optimum media composition derived from Response Surface Methodology (RSM) was consists of (per liter): peptone, 54.99g; NaCl, 2.92; olive oil, 5.48ml with the lipase activity was 687 U/ml. Optimum culture conditions was observed when 7% Bacillus cereus inoculated in the media containing above composition at pH 6.91 with agitation rate of 234 rpm for 24 hours. The lipase activity had increased more than 30% (1020 U/ml) upon the exposure in the optimum media and culture condition. Crude extracellular lipase enzyme was characterized for its activity and stability profile towards pH and temperature and both pH 6.0 and temperature, 30°C were observed to be the best condition for enzyme in 25 hours incubation.

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Preliminary Study of Monosex Red Hybrid Tilapia (tilapia sp.) Seed Production and Its Health Management

Written by hidayah. Posted in Research

  • Researcher : Dr. Lee Seong Wei
  • Student        :  Tuan Nur Izzatie Azie bt Zulkefli
  • Grant            : Short Term Research Grant

ABSTRACT

Aquacultures of tilapia have been increasing due to high global demand. Tilapia was a major contributor to world food security (Food Agriculture Organization). So this study will be conducted for improving technology in aquaculture industry. The study is carried out to evaluate the effectiveness of the commercial hormone and plant extract to make sex reversal in tilapia and its health management. The one day old tilapia will be purchase from Pusat Perikanan Machang Kelantan. The requirements for maintaining the fry will be supply adequately such as aeration, feed and water quality during the treatment period. The fry will be raised and treat with the hormone and plant extratct. Two type of traditional herb which are  Polyalthia bullata (Tongkat Ali hitam) and Jackiopsis ornata (Aji Samad) will be used.  This herbal plant have been using in Malay community as aphrodisiac to stimulate sex. The plant will be grind and soak into water for five concentration 1g/l, 2g/l, 4g/l, 8g/l, and 16g/l. After that the solution will be filter with whittman filter paper. Then the fish will be kept into the solution for two weeks. While two type commercial hormone which are ethestosterone and 17α methyltestosterone also prepared for five different concentrations. The fry will be raised and treat with the hormone and plant extract until it becomes 2-3cm. After that the fry are ready to analyses for sex determination. The methyl blue will be used to determine the sex of the fish. For health management bacteria colonized diseases monosex red hybrid tilapia will be isolated and identified based on conventional biochemical tests (Holt et al. 1994) and confirmed with commercial identification kit (BBL, USA). Then the project will be follow by analyses of effectiveness of antibiogram and plant extract in controlling photogenic bacteria. About 19 types of antibiotic and 13 species of plant will be extracted as natural bacteria agent for the treatment of the tilapia fish disease. The plant extractions were used 70% of methanol. In the end of the study we can determine the sex of the fish and evaluate the effectiveness of the plant extraction in sex reversal and compare to the commercial hormone. Besides, the data from this study also can be used for controlling disease cause by bacteria in tilapia.

Keywords: Red hybrid tilapia, sex reversal, antibiotic, bacteria