Kesan perencatan enzim oleh perencat merupakan suatu isu biasa dalam process
biokatalisis. Dalam kajian ini, kesan suhu terhadap mekanisma perencatan telah
dikaji. Hydrolisis 4-nitrophenol butyrate (4NPB) oleh lipase telah digunakan sebagai
model tindak balas. Sebelum kajian ini dilaksanakan, kesan kepekatan substrat dan
suhu telah dikaji. Akhir sekali, kesan metanol sebagai perencat untuk lipase dari jenis
Candida rugosa dan mekanisma perencatan serta kinetiknya pada suhu yang berbeza
telah dibandingkan. Kadar tindak balas meningkat apabila kepekatan substrat
meningkat dari 1.0 M kepada 5.0 M. Apabila kepekatan substrat meningkat dari 10.0
M kepada 15.0 M, kelajuan tindak balas adalah malar. Suhu yang sesuai berada pada
40 ℃ apabila pH 7.2 digunakan. Akhir sekali, kajian telah mendapati bahawa
mekanisma perencatan Candida rugosa lipase pada 30 ℃ dan 40 ℃ adalah
perencatan tidak bersaing. Manakala, pada suhu 50 ℃, mekanisma perencatan adalah
berdaya saing. Bagi kinetik enzim pada 40 ℃, kelajuan maksimum adalah lebih
tinggi, produk mudah untuk terbentuk manakala kesan perencat adalah ketara
berbanding pada suhu 30 ℃. Apabila kinetik enzim dibandingkan berdasarkan
kepekatan perencat, bagi perencatan tidak bersaing, Vmax *, Km * dan KI telah
menurun. Bagi perencatan berdaya saing, Vmax* kekal malar, Km* meningkat
manakala KI berkurang.
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Enzyme inhibition by the inhibitor is a common issue in the bio-catalysis. In this
work, the effect of temperature on the inhibition mechanism was investigated.
Lipase-catalyzed hydrolysis of 4-nitrophenol butyrate (4NPB) was used as a model
reaction. Prior to the investigation, the effect of substrate concentration and
temperature were studied. Finally, the effect of methanol as an inhibitor to Candida
rugosa lipase and mechanism of inhibition as well as its kinetics at different
temperatures were compared. Rate of reaction increased proportionally with
substrate concentration from 1.0 M to 5.0 M. When substrate concentration increased
from 10.0 M to 15.0 M, the reaction velocity was constant. The ideal temperature
was found to be at 40 ℃ when the pH of 7.2 was used. Lastly, it was found that the
mechanism of inhibition of Candida rugosa lipase at 30 ℃ and 40 ℃ were
uncompetitive inhibition. Whereas at temperature 50 ℃, the mechanism of inhibition
is competitive inhibition. For enzyme kinetics at 40 ℃, the maximum velocity is
higher, product easy to form while the inhibitory effect is significant compared to at
temperature 30 ℃. When the kinetics is compared based on the concentration of
inhibitor, for uncompetitive inhibition, Vmax*, Km* and KI were decreased. For the
competitive inhibition, the Vmax* remained constant, Km* increased while the KI was
decreased.
The effect of temperature on the inhibition mechanism of candida rugosa lipase / Nurul Afini Fuad