Centre for Bioprocess Engineering, School of Chemical Engineering, University of Birmingham, Edgbaston,
Birmingham, B 15 2TT, UK.
¹Department of Chemical and Environmental Engineering, Faculty ofEngineering,
Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia
²Lonza Biologic Plc, 228, Bath Road, Slough, Berkshire, SL1 4DY, UK

Received 28 February 2001 /Accepted 15 March 2001

Abstract.
The importance of programmed cell death or apoptosis during the cultivation of animal cell lines is becoming increasingly apparent. Because apoptosis contributes to a diverse variety of adverse and undesirable processes, understanding its regulatory control might provide insight into the mechanism of these conditions and suggest novel strategies to improve cell viability and productivity. In this review we describe the morphological and biochemical characteristics of the two distinct forms of cell death (apoptosis and necrosis) and the common techniques used to identify them. The mechanisms involved in apoptosis and its regulation at the molecular level aswell as the involvement and role of factors that appear to participate in the apoptotic process are also described. We also discuss progress on the development of novel solutions to improve culture productivity through the apoptotic route with illustrations of practical applications from the authors' own research.

Keywords: Apoptosis, programmed cell death, cell culture, biotechnology, bioreactor, survival gene

Department of Clinical Laboratory Sciences, Faculty of Medicine and Health Sciences, Universiti Putra
Malaysia, 43400 UPM Serdang, Selangor; ¹Department of Parasitology and Medical Entomology,
Faculty of Medicine, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz,
50300 Kuala Lumpur1 ; ²Department of Biotechnology, Faculty of Food Sciences and Biotechnology,
Universiti Putra Malaysia, 43400 UPM Serdang, Selangor

(Received 10 March 2000 / Accepted 18 February 2001)

Abstract.
The performance of a newly developed dipstick colloidal dye immunoassay (DIA) was compared with that of a previously described Sandwich ELISA to detect parasite antigens in sera from patients with brugian filariasis. The rabbit polyclonal antibodies (RbBmCAg) and the same patients' sera were used in both the tests. In the DIA, 69 of 70 sera from well characterized microfilaremic patients were deemed to contain filarial antigens when screened at a dilution of 1:50. End titres were 1: 10 to 1280. The specificity of both assays was >95% but their sentivity was remarkably different. We have used 6 µl of the RbBmCAg per dipstick in comparision to 150 ?l per well for Sandwich ELISA. The DIA is a rapid test and can be read in approximate 2 h. In addition, coloured dots developed in the DIA can be qualitatively assessed visually for intensity. The DIA does not require sophisticated equipment or radioactivity, and is therefore suitable for field application.

Keywords: Dipstick, Colloidal Dye, Immunoassay, Filariasis

Molecular Biology and Biotechnology Laboratory, Faculty of Resource Science and Technology, Universiti Malaysia Sarawak,94300 Kota Samarahan, Sarawak, Malaysia.

(Received 12 June 1998 / Accepted 12 December 2000)

Abstract.
Genomic DNA from sago palm was isolated using the cetyltrimethlammoniurn bromide (CTAB) method with some modifications. The RAPD technique, employing ten base synthetic oligonucleotides, was used to generate molecular markers for this tropical palm. Successful amplification of the sago genomic DNA was also obtained using a microsatellite sequence (GATA)4, These molecular markers will be potentially useful for genetic fingerprinting of sago palm for future breeding programmes.

Keywords: Sago palm, Molecular Markers, RAPD

¹Jabatan Kimia, 2Jabatan Biokimia dan Mikrobiologi, Fakulti Sains & Pengajian Alam Sekitar Universiti
Putra Malaysia, 43400 UPM Serdang, Malaysia.

(Received 12 December 2000 / Accepted 10 April 2001)

Abstract.
Enzymatic synthesis of medium chain glycerides (MCG) from caprylic acid and glycerol was studied using lipase from Candida rugosa. The effects of various reaction parameters such as time course, type of organic solvents, molar ratio of substrates (mmol glycerol/mmol capric acid), amount of enzyme, and initial water activity (aw) were studied. The best condition tested for MCG synthesis at 37oC were respectively, at time, 24 h: molar ratio of substrates, 0.4 and amount of enzyme, 100.0 mg. Generally, the activity of lipase was high in non polar solvents with log P values from 3.60 to 5.60. The enzymatic synthesis of MCG was preferably carried out at an initial aw of 0.328, which resulted in maximum yield. Analysis of the products of reaction using gas chromatography showed that lipase from Candida rugosa seemed to produce only dicaprylin and tricaprylin.

Keywords: medium chain glycerides, lipase, esterification, solvents, water activity