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All Journal Journal of Biobased Chemicals (JOBC)
Rizki Fitria Darmayanti
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Chemical Engineering, Chemistry & Bioengineering Chemistry

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Biobutanol Production Using Fed-Batch High-Cell Density Extractive Fermentation Rizki Fitria Darmayanti; Yukihiro Tashiro; Kenji Sakai; Kenji Sonomoto
Journal of Biobased Chemicals Vol. 1 No. 1 (2020): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (782.366 KB) | DOI: 10.19184/jobc.v1i1.108

Abstract

Butanol, as a product with specific toxicity for its producer, is necessary to be maintained in low concentration during fermentation. In-situ integrated recovery using extensive volume extraction was used in high cell density fermentation in order to prevent the lag phase in the prime condition. Clostridium saccharoperbutylacetonicum N1-4 ATCC 13564 was employed to ferment glucose in extractive fermentation with oleyl alcohol as extractant. As the results of fed-batch cultures using high cell density with different extractant to broth volume ratios (Ve/Vb), 0.8 g/l butanol concentration in the broth was maintained with a ratio of 10, which was much lower than 4.4 g/l with the ratio of 0.5. Besides, the Ve/Vb ratio of 10 demonstrated 2.7-fold higher total butanol concentration (28 g/l) than that 11 g/l obtained with a Ve/Vb ratio of 0.5. These results indicated that larger Ve/Vb improved total butanol concentration by reducing butanol toxicity in broth.
Quantitative Structure-Activity Relationship Study of Ester-Based Ferulic Acid Derivatives Against Cervical Cancer Cell (HELA) Helda Wika Amini; Istiqomah Rahmawati; Rizki Fitria Darmayanti; Boy Arief Fachri
Journal of Biobased Chemicals Vol. 1 No. 1 (2020): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (641.554 KB) | DOI: 10.19184/jobc.v1i1.109

Abstract

Quantitative structure-activity relationship (QSAR) has been studied for ferulic acid derivatives to determine the QSAR model able to predict anticancer. As the subject of this research was a set of experimentally calculated IC50 value data of 6 ferulic acid derivatives against cervical cancer cells (HELA). QSAR analysis was based on multilinear regression calculation on fitting subset using log (1/IC50) as the dependent variable, and dipole moment, partition coefficient in the n-octanol/water, and atomic net charges of the aromatic carbons as independent variables. The values of the descriptors were obtained from semiempirical PM3 quantum mechanic calculation. The relationship between log (1/IC50) and the descriptors was described by the result in the QSAR model. The QSAR model for ferulic acid derivatives against HELA cell lineswas developed with the statistical parameters of R=0.998; R2=0.999; SE=0.00857; and F=394. The calculated log (1/IC50) using QSAR Hansch Model for ferulic acid derivatives have excellent agreement with experimental data of Log (1/IC50).
Optimization of Subcritical Water Assisted by Nitrogen Before Enzymatic Hydrolisis for Reducing Sugar Production Maktum Muharja; Nur Fadhilah; Rizki Fitria Darmayanti; Dwina Moentamaria; Arief Widjaja
Journal of Biobased Chemicals Vol. 1 No. 1 (2020): Journal of Biobased Chemicals
Publisher : Program Studi Teknik Kimia Universitas Jember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (892.156 KB) | DOI: 10.19184/jobc.v1i1.110

Abstract

The objective of this study is to optimize the three significant parameters of the subcritical water (SCW) process for sugarproduction from coconut husk by using response surface methodology (RSM). In this study, the effect of temperature, reaction time and solvent-feed (S/F) ratio was evaluated and discussed comprehensively. The results showed that the S/F ratio had the most significant effect on sugar yield. The optimal sugar yield was obtained at the highest S/F ratio of 23.4, the shortest time of 4.8 min, and the highest temperature of 183.6 oC of the SCW process. The characterization resultsconfirmed that the lignocellulose structure was changed remarkably then contribute to the efficient processes of enzymatichydrolysis. The parameters evaluation using RSM in this study suggests that SCW hydrolysis could be subjected to commercial purposes.
Co-Authors Arief Widjaja Boy Arief Fachri Dwina Moentamaria Helda Wika Amini Istiqomah Rahmawati Kenji Sakai Kenji Sonomoto Maktum Muharja Nur Fadhilah Yukihiro Tashiro