Sains Malaysiana 31: 109-115 (2002)                                                                           Sains Fizis dan Gunaan /

                                                                                                                                                Physical and Applied Sciences

Penurunan Sikloheksanon kepada Sikloheksanol oleh bakteria penghasil

aseton-butanol, Clostridium acetobutylicum NCIB 8052

(Reduction of cyclohexanone to cyclohexanol by acetone-butanol

producing bacteria, Clostridium acetobutylicum NCIB 8052)

Mohd Sahaid Kalil & Noorhisham Tan Kofli

Jabatan Kejuruteraan Kimia dan Proses

Fakulti Kejuruteraan

Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

ABSTRAK

Penyelidikan ini bertujuan mengkaji tindak balas penurunan sikloheksanon kepada sikloheksanol secara biotransformasi menggunakan Clostridium acetobutylicum NCIB 8052. C. acetobutylicum ditumbuhkan dalam media RCM dalam kultur tiub yang mengandungi sikloheksanon pada kepekatan 1­30 mM. Kajian biotransformasi dalam fermenter dilakukan menggunakan media minima glukosa yang mengandungi sikloheksanon (5 mM). Hasil biotransformasi dianalisis menggunakan kromatografi gas (GC). Kepekatan sikloheksanol yang terhasil didapati meningkat secara linear dengan peningkatan substrat yang diberikan sehingga 10 mM. Kepekatan substrat yang lebih tinggi secara relatifnya tidak meningkatkan hasil. Kajian ini menunjukkan bahawa biotransformasi sikloheksanon merupakan proses yang tidak berkait dengan pertumbuhan dan penghasilan butanol merupakan pra­syarat untuk biotransformasi.

ABSTRACT

The aim of this project was to investigate the reduction of cyclohexanone to cyclohexanol by Clostridium acetobutylicum NCIB 8052. C. acetobutylicum was grown in a tube culture containing RCM medium with added cyclohexanone at concentrations of 1-30 mM. Biotransformation studies in a fermenter was carried out using glucose minimal media containing 5 mM cyclohexanone. Products were ana lysed by gas chromatography (GC). It was found that cyclohexanol concentration increased with an increase in substrate concen­tration up to 10 mM. However, higher substrate concentration did not increase product concentration. This study showed that biotransformation of cyclohexanone was not growth-linked and the production of butanol was a prerequisite for biotransformation to occur.

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