Elaine Remi Anak Douglas Telajan, (2009) Isolation and characterisation of fibrolytic and lipolytic enzymeproducing bacteria from oil palm empty fruit bunch compost. Masters thesis, Universiti Malaysia Sabah.
Palm kernel cake (PKC) is an important oil palm by-product. PKC has been widely used as animal feed especially for ruminants and poultry. The inclusion of PKC in poultry diet is limited due to the presence of several anti-nutritive fibrous materials in PKC such as galactomannan and xylan. These anti-nutritive materials increase the viscosity of the diet due to their high absorbability of water and therefore inhibit the absorption of nutrients by the animals. One way to overcome this problem is to treat PKC with enzyme or enzyme-producing microorganisms to digest those recalcitrant components. Hence, this work was carried out to isolate microorganisms; especially mesophilic and thermophilic bacteria with fibrolytic activities such as galactomannanase, xylanase, cellulase, and lipase which can be used to treat PKC. Apart from that, these bacteria may also increase the nutritive value of PKC as single cell proteins (SCP). Isolations were carried out using the dilution plate method on Nutrient agar medium for bacteria, Starch Casein Nitrate agar medium (SCA) for mesophilic actinomycete, Czapex-dox Yeast Extract Casamino Acid agar medium (CYC) for thermophilic actinomycete, yeast extract peptone glucose agar medium (YEPD) for yeast and potato dextrose agar medium (PDA) for fungi. Commercially available substrates; Azo-carob-galactomannan, Azoxylan (oat) and Azo-CM-cellulose were used to screen for galactomannanase, xylanase and cellulase activities, respectively. Sobitan monolaurate (Tween 20) was used as the substrate for lipase activity. A total of 1146 colonies were isolated from various empty fruit bunch (EFB) compost samples, effective microbe solution and raw EFB. Out of that number, a total of 627 bacteria, 219 actinomycetes, 101 yeast and 199 fungi were isolated and screened. Sixteen isolates with the ability to produce mannanase, cellulase and xylanase were assayed using quantitative assay techniques for the measurements of mannanase, cellulase and xylanase activities. These assays indicated that three isolates of the Baciflus sp. exhibited significantly higher activity of mannanase (Isolates 7DY7, 7DU3 and 4DB3 with maximum activity of 1.30 U/µg protein, 0.95 U/µg protein and 0.92 U/µg protein respectively), cellulase (Isolates 7DY7, 7DU3 and 4DB13 with maximum activity of 0.08 U/µg protein, 0.35 U/µg protein and 0.11 U/µg protein respectively) and xylanase (Isolates 7DY7, 7DU3 and 4DB8 with maximum activity of 0.15 U/µg protein, 0.08 U/µg protein and 0.21 U/µg protein respectively) compared to the other 13 bacterial isolates. The 16 isolates were identified using their 165 rDNA sequences. Eleven Bacillus sp. and a single isolate of Micromonospora sp., Streptomyces sp. and Thermoactinomyces sp. were identified by comparing the partial 165 rDNA sequences of the isolates in this work to 165 rDNA sequences in the GenBank using the Basic Alignment Search Tool (BLAST). These microbes could be used to treat PKC to increase the nutritive value of PKC.
|Item Type:||Thesis (Masters)|
|Uncontrolled Keywords:||isolation, oil-palm, fibrolytic, lipolytic, fruit bunch compost, enzyme-producing microorganism|
|Subjects:||S Agriculture > SB Plant culture|
|Divisions:||SCHOOL > Biotechnology Research Institute (BRI)|
|Deposited By:||IR Admin|
|Deposited On:||25 Jun 2013 12:26|
|Last Modified:||25 Jun 2013 12:26|
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