J. Hamed, M.A. Hassan^*,1Y Shirai, A. Ariff
and M.I.A. Karim

Department of Biotechnology, Faculty of Food Science and Biotechnology,
University Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
¹Department of Biochemical Engineering and Science, Faculty of Computer Science and Systems Engineering,
Kyushu Institute of Technology, Iizuka, Fukuoka 820 8502, Japan

Received 3 January 2000 / Accepted 5 July 2000

Abstract.
Leachates from municipal solid wastes (MSW) in Kuala Lumpur area were subjected to anaerobic treatment under specified conditions for the production of short chained organic acids. Two different leachate samples were used in this study; fresh leachate from the city council garbage trucks and combined leachate taken from several cells at the sanitary landfill. The objective is to evaluate the effect of pH and inoculum on organic acids production during anaerobic treatment of leachate from MSW. Treatments were carried out at 30^oC for 7 10 days under different conditions of pH such as uncontrolled pH, adjusted to initial pH 7, controlled at pH 7 for 24 h, and continuous control at pH 5.5 and pH 7. The production of organic acids from fresh leachate was highest when the pH was adjusted initially to pH 7 with no further pH control. About 45 g/L total organic acids was produced after five days of treatment, with 28 g/L lactic acid, 8 g/L acetic acid and 9 g/L propionic acid. Based on the initial BOD, the organic acid yield was about 80%. In contrast, with the combined landfill leachate the highest organic acids production obtained was only 14 g/L when the pH was controlled at pH 5.5, with acetic acid as the main product. Lower pHs appeared to increase organic acids production in the combined landfill leachate. When the fresh leachate was autoclaved and seeded with 10% fermented kitchen garbage, the highest organic acids achieved were between 34 37 g/L. The highest selectivity of lactic acid (85%) was achieved during treatment of fresh leachate seeded with kitchen garbage without any pH adjustment. Overall, our results showed that the fresh leachate could be effectively converted to 45 g/L total organic acids by anaerobic treatment when the initial pH was adjusted to pH 7.

Keywords: Organic acids, municipal solid waste, landfill leachate

¹Department of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia,
43600, Bangi, Selangor ²Malaysian Palm Oil Board, P.O. Box 10620, 50720 Kuala Lumpur, Malaysia

Received 19 September 1999 / Accepted 25 February 2000

Abstract.
Oil palm Elaeis guineensis Jacq is the second largest contributor of edible oil to the total fat and oil production in the world. Malaysia is at present the largest producer and exporter of palm oil. Breeding programs are being carried out in order to increase the yield, quality of oil as well as other agronomically important characters. Understanding the genetic diversity in germplasm materials is of prime importance in these breeding programmes. In this study we employed the method of AFLP to study the genetic variation present in an oil palm germplasm collection. We screened germplasm collected from Nigeria, Madagascar, Democratic Republic of Congo (Congo) and Gambia. Ten palms from each country were selected. All together 38 genotypes were analyzed by the AFLP technique using three primer combinations of EcoRl and Mse l. The total number of bands scored was 233 of which 206 (88%) were polymorphic. The total number of bands produced by different primer pair combinations ranged from 64 to 101. Analyses of the results were carried out to determine the degree of heterogeneity and similarity between the population and two dendrograms were generated.

Keywords: Oil palm, AFLP, germplasm, polymorphism, Elaeis guineensis

¹Institute of Biological Science, Faculty of Science, 2Department of Medical Microbiology,
Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia

Received 21 September 2001 / Accepted 10 December 2001

Abstract.
Pulsed field gel electrophoresis (PFGE) despite being a highly reproducible and discriminatory method for molecular subtyping of many bacterial pathogens has been criticised for being time consuming. We have developed a modified, rapid PFGE method for Gram positive bacteria, in particular, Streptococccus spp. Our method can be completed in only 3 days' time as compared to the standard procedure which required Lip to 6 days. We successfully applied this method on clinical isolates of Streptococcus pneumoniae (50) and Group B Streptococcus (50) obtained from the University of Malaya Medical Center with comparable results. The method for DNA preparation was reproducible when repeated analysis was carried out. The rapid method has the ability to process a large number of isolates in less time than the standard method. This will definitely enhance the rapid and accurate analysis of outbreaks of nosocomial or community acquired Streptococcal infections.

Keywords: Rapid protocol, PFGE, Streptococcus spp.

Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia

Received 2 August 2001 / Accepted 5 September 2001

Abstract.
Pulsed field conditions specific for Pasteurella multocida B:2 have been optimised to obtain a good separation resolution. Restriction enzyme, NotI, was the most suitable as it generates discernible number of bands. Other optimised electrophoretic conditions were: 1.5% agarose gel concentration, 200 V, ramped pulsed time of 1-25 s and a run time of 26 h. This research is important for fast and accurate characterisation of this bacterial strain following an outbreak in Malaysia.

Keywords: Pasteurella multocida, PFGE, restriction enzymes