Garuda - Garba Rujukan Digital

Article Per Year (5 Year)

All

ASEAN Journal of Chemical Engineering

AJChE
Website

Published by Universitas Gadjah Mada

ISSN : 26555409 EISSN : 26555409 DOI : https://doi.org/10.22146/ajche.52004

Core Subject : Science, Engineering,

Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry

The ASEAN Journal of Chemical Engineering publishes papers on Chemical Engineering, specifically but not limited to the areas of thermodynamics, reaction kinetics, transport phenomena, process control, environment, energy, biotechnology, corrosion, separation science, powder technology, materials science, and chemical engineering education

Arjuna Subject : Teknik Kimia (semua kategori) - Kimia Proses dan Teknologi

Articles 8 Documents

Search results for , issue "Vol 12, No 2 (2012)" : 8 Documents clear

Equilibrium Study on Reactive Extraction of Lactic Acid with Tri-n – Butyl Phosphate in n - Hexane Panut Mulyono; Anita Pardah
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Extraction of carboxylic acids from dilute aqueous solution using traditional solvents such as ketones, alcohols, ethers, and ester is inefficient because the distribution ratio is rather low. Reactive extraction which exploits reversible chemical complexation is an effective separation process for extraction of carboxylic acids from aqueous streams such as fermentation broths and wastewaters. In the extraction process, selection of the solvent is an important aspect to be considered. Considering its solubility in water, cost and availability, tri-n-butyl phosphate (TBP) seems to be an attractive solvent for the extraction of lactic acid from aqueous solution. The purpose of this experiment is to study the equilibrium of the reactive extraction of lactic acid in aqueous solution with TBP in n-hexane. The parameters studied in this experiment were initial concentration of lactic acid in the aqueous phase, TBP concentration in n-hexane phase, and the extraction temperature. The experiments at ambient temperature were carried out using a separatory funnel, while the experiments at other than ambient temperature were carried out using erlenmeyer flask and water bath shaker to adjust the temperature. In this experiment, the initial concentration of lactic acid was varied from 0.1 to 0.5 gmol/dm3. The range of initial TBP concentrations in n-hexane was 0.1 to 1.0 gmol/dm3 and the extraction temperature range was 283 to 313 K. The experimental results showed that the higher the initial concentration of lactic acid in aqueous solution, the higher the distribution ratio for a fixed TBP concentration and extraction temperature. For a fixed initial concentration of lactic acid in aqueous solution and extraction temperature, the distribution ratio of lactic acid is increased by increasing TBP concentration. The overall equilibrium constants (Kpq) for the experiments using TBP concentration ranging from 0.1 to 1.0 gmol/dm3 at the extraction temperature of 293 K are calculated to be 0.0668 to 0.5144. Kpq for the experiments at the temperature ranging from 283 to 313 K at the initial concentration of lactic acid of 0.2 gmol/L are found to be 0.0122 to 0.8856. The Kpq as a function of temperature (T) in K can be expressed as ln Kpq = 10,596/T - 38.08 with sum of square of error of 0.14.

Comparison of Cutinase Separation in Different Chromatographic Media Abdul Wahab Mohammad; Jamaliah Md.Jahim; Suhaila Johar; Osman Hassan
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Cutinase is a hydrolytic enzyme that has both properties of lipase and esterase, thus finding its use in many areas. Previous studies have investigated both upstream and downstream processes for cutinase production from microbial source. However, no study has yet to address the use of membrane chromatography for cutinase purification, which is more favourable in terms of process resolution and product throughput as compared to the conventional gel chromatography. Hydrophobic interaction was chosen as the separation mechanism for cutinase purification in this study. The optimisation of cutinase purification in two different types of chromatographic media; conventional packed-gel and membrane matrix, were pre-determined by the best compromise between the recovery and purity of the purified cutinase. It was found that the optimised condition were of pH 4.0 and 1.0 M ammonium sulfate for the conventional column (50% recovery, 4.8-fold purity) and pH 6.0 with 1.5 M ammonium sulfate for the membrane–matrix column(87% recovery, 30-fold purity). Preferential interaction analysis was used to describe the protein chromatographic behaviour in each chromatographic media. Graph of natural algorithm of protein retention data to the function of salt concentration at pH 4.0 and 6.0 for each column were plotted. It was found that at the optimum pH condition for gel-packed column, a small amount of ammonium sulfate was sufficient to achieve maximum cutinase recovery and purity since the effect of salt at that particular pH were less significant. Consequently, the number of released water molecules were calculated and it was observed that for membrane column, larger number of water was released at pH 6.0 illustrating more protein were bounded to the stationary phase, thus explaining the optimum pH condition of the particular column.

Co-solvent Selection for Supercritical Fluid Extraction of Essential Oil and Bioactive Compounds from Polygonum minus Masturah Markom; Norsyamimi Hassim; Nurina Anuar; Syarul Nataqain Baharum
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

This study evaluated the biological activity (antioxidant assay) of Polygonum minus extracted using Supercritical Fluid Extraction (SFE) added with different types of co-solvents. The seven co-solvents employed were water, methanol, ethanol, 50% methanol, 50% ethanol, 70% methanol and 70% ethanol for selection of the best co-solvent prior to optimization of SFE. 70% methanol produced the highest total yield of extract (33.1%) compared to other co-solvents. The antioxidant capacity was then evaluated using four different assays: the total phenolic content (TP), the total flavonoid content (TF), the ferric reducing/antioxidant power (FRAP) and the free radical-scavenging capacity of 2,2-diphenyl-1-picrylhydrazyl (DPPH). The highest TP and TF were from 70% methanol extract (11.2 ± 0.15 mg GAE/g sample (mg GAE/g) and 11.9 ± 0.03 mg CAE/g sample (mg CEQ/g) respectively). 70% metanol extract also showed the highest FRAP value (346.7 ± 0.66 µmol Fe (II)/g sample) and the highest percentage of DPPH radical inhibition was also shown by 70% methanol extract (88.7 ± 0.40%). There was a positive correlation between the antioxidant capacity (FRAP and DPPH) with those of TP and TF contents. Therefore, the best co-solvent chosen for further optimization of SFE is 70% methanol.

Effects of Fluxing Agents on Filter Aids Prepared from Lam-Dong Diatomate Mai Thanh Phong; Tran Duy Hai; Phan Dinh Tuan
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Diatomite (or kieselguhr) is deposit of skeletal remains of single-cell water plants (diatom algae). Diatomite can be used as raw materials for production of several products, such as filter aids, fire-bricks, adsorbents, etc. Two major deposits of diatomite in Vietnam are in Phu-Yen and Lam-Dong province. This study aims to study preparation of filter aids from Lam-Dong diatomite. Especially, the study focused on investigating effects of fluxing agents on quality of filter aids. Physic-chemical properties of the filter aids were determined by using X-ray fluorescence spectrometer, scanning electron microscope and instrumentally measured color coordinates. Results of beer filtration were also presented in this paper. The obtained results proved that Lam-Dong diatomite can be used to manufacture standard filter aids for beer filtration.

A Dynamic Model for Ultrasonic – assisted Extraction of Bio-active Compounds from Natural Products Trung Kien Tran; Lan Huong Phung; Hoai Nga Le; Thi Thu Huyen Nguyen; Xuan Son Nghiem; Van Thiem Pham
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Ultrasonic technique has been applied for extraction processes, especially for separation of bio-active substances from natural organic products because of the short time requirement, energy saving and easy operating. The ultrasonic-assisted extraction (UE) therefore becomes a promising option. However, a major available obstacle was the lack of appropriate models for designing technological process. This paper presents a dynamic model for the UE process, application of separation of bio-active substances from natural products such as Curcumin from rhizome of Curcuma Longa L., Epigallocatechin from green tea leaf of Camellia Sinensis and Rutin from bud of Sophora Japonica. The agreement between data from experiment and calculated ones with the model indicates that, this dynamic model is suitable for prediction of the UE process and for serving as the base for further investigation into scale-up the extraction process.

Research on Biological Activity of some Extracts from Vietnamese Carica papaya Leaves Do Thi Hoa Vien; Phung Thi Thuy
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Carica papaya leaves have long been used in some folk remedies to treat cancer. This folk remedy originated from Queensland - Australia from 1978 (Harald W. Tietze, 1997). In Vietnam, there are some successful cases of using Carica papaya leaves for cancer treatment even though this mediation do not always work out. In this study, the soluble substances in water (aqueous extract), the carotenoid and the polar substances (polar extract) were extracted from Carica papaya leaves grown in Vietnam; the bioassays such as cytotoxicity on some tumor cell lines as well as antioxidant activity were also tested with obtained extracts. The results showed that all obtained extracts had antioxidant activity stronger than the control substance - vitamin C at the same tested concentration. At concentration of 100 μg/ml, the inhibitive activity on lung cancer cell line LU-1 of obtained extracts was highest, from 43.47% (aqueous extract) to 62.88% (polar extract). On carcinoma cell line KB, inhibitive ability of extracts was lower: 2.8% (polar extract) and 20.6% (aqueous extract). On the breast cancer cells MCF7, inhibitive ability of above extracts was quite high, from 33.95% to 56.19%. On the leukemia cell line HL 60, inhibitive ability of these extracts was also high, from 39.56 to 60.64%. In addition, the result pointed out that on stem cells isolated from mouse embryos (ESC), the obtained extracts was not toxic to healthy cells of this line. This suggested that extracts from Carica papaya leaves has the potential to become one of the natural substance products that can support cancer treatment in certain cases.

Optimization Research into the Ultrasonic-assisted Extraction to Separate Polyphenol from Green Tea Waste Lan Huong Phung; Trung Kien Tran; The Cuong Nguyen; Hong Quang Do; Thu Tra Phan; Hong Son Vu; Tien Huy Nguyen
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Today, green tea leaves (Camellia sinensis) have been grown in nearly 30 provinces in Vietnam. Catechins, which are polyphenols, are abundant in green tea. In a freshly picked tea leaf, polyphenols can compose up to 30% of the dry weight. Recently, researchs have focused on tea polyphenols due to its potent anti-oxidant activity, anti-inflammatory and anti-cancer effects. Viet Nam currently ranks the fifth in the world in tea production and export turn-over. However, green tea is made from the top two leaves and buds of a shrub. A large amount of stems, older leaves and tea wastes from tea factories is not produced. For this reason, study to separation polyphenols from these materials plays an important role in science, society and economy. Polyphenols can be extracted from green tea leaves by using hot water and organic solvents. In the method of using hot water, green tea quality deteriorates and catechins are destroyed due to the heat applied. Therefore, we attempted to increase the amount of polyphenols in extracts with using ultrasonic irradiation at low temperature. This work has an aim to investigate the influent process parameters such as extraction time, stirring speed and the rate of raw material/solvent on efficiency of the extraction of polyphenols and antioxidant properties obtained extracts. The ultrasonic-assisted extraction was conducted at room temperature, ultrasound frequency (25 kHz) using water solvent. Extracts were analysed for total phenols content (TPC) by the Lowenthal method. The antioxidant properties have been determined by DPPH free radical scavenging effect, The results of the work are the basis to determine of the optimal technological factors by employing desirability methodology with experimental order of Box-Behnken design and to scale up for designed industrial extraction system that can be applied in tea plants for the production of tea polyphenols from tea wastes.

Optimisation of LS54/Dx Aqueous Two Phase System Conditions for Cutinase Recovery Jamaliah Md. Jahim; Abdul Wahab Mohamad; Fariza Akmal Abdul Mutalib; Farah Diba Abu Bakar; Osman Hassan
ASEAN Journal of Chemical Engineering Vol 12, No 2 (2012)
Publisher : Department of Chemical Engineering, Universitas Gadjah Mada

Aqueous two phase system comprising Dehypon® LS 54 and K4484 Dextrin® was selected for recovery of cutinase enzyme. Parameters such as pH, system composition and type of salt as an additive, influenced the protein partitioning behaviour and optimisation of these parameters become necessary to be done in the design of primary recovery process of ATPS. The cutinase partitioning experiments were carried out with 30% of cutinase solution added to LS 54/Dx system. Results showed that cutinase enzyme preferred to partition into LS 54 rich-phase at pH 8.0 and the affinity of cutinase into top phase was observed higher with the increment of system compositions, which represented by tie line length (TLL). Furthermore, the addition of 50mM salts such as K2SO4 and KCl into LS 54/Dx system has led to raise partition coefficient of cutinase, kcut to 2.2 and 1.95 fold, respectively. The dependence of kcut on various additives such as (NH4)2SO4, Na2SO4 and K2SO4 at the same concentration, suggested that the addition of selected ions could enhance positive electrostatic potential which could attract more cutinase to partition into LS54 rich phase. As conclusion, the best conditions obtained for cutinase partitioning were pH8.0, TLL = 23% and Na2SO4 = 50mM, from which the maximum kcut of 2.83 with improved recovery of cutinase in top phase up to 79% can be achieved.

Page 1 of 1 | Total Record : 8

Filter by Year

2013 2013

Filter By Issues

All Issue Vol 23, No 3 (2023) Vol 23, No 2 (2023) Vol 23, No 1 (2023) Vol 22, No 2 (2022) Vol 22, No 1 (2022) Vol 21, No 2 (2021) Vol 21, No 1 (2021) Vol 20, No 2 (2020) Vol 20, No 1 (2020) Vol 19, No 2 (2019) Vol 19, No 1 (2019) Vol 18, No 2 (2018) Vol 17, No 1 (2017) Vol 18, No 1 (2018) Vol 17, No 2 (2017) Vol 16, No 2 (2016) Vol 16, No 1 (2016) Vol 15, No 2 (2015) Vol 15, No 1 (2015) Vol 14, No 2 (2014) Vol 14, No 1 (2014) Vol 13, No 2 (2013) Vol 13, No 1 (2013) Vol 12, No 2 (2012) Vol 12, No 1 (2012) Vol 11, No 2 (2011) Vol 11, No 1 (2011) Vol 10, No 2 (2010) Vol 10, No 1 (2010) Vol 9, No 2 (2009) Vol 9, No 1 (2009) Vol 8, No 1 & 2 (2008) Vol 2, No 1 (2002) Vol 7, No 1 & 2 (2007) vol. 6 no. 2 (2006) Vol 6, No 1 (2006) Vol 5, No 2 (2005) Vol 5, No 1 (2005) Vol 4, No 2 (2004) Vol 4, No 1 (2004) Vol 3, No 1 (2003) Vol 1, No 1 (2001) More Issue

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name
Ari Pramudyantoro

Contact Email
ajche.ft@ugm.ac.id

Phone
+62274555320

Journal Mail Official
ajche.ft@ugm.ac.id

Editorial Address
Jln. Grafika No. 2 Kampus UGM Yogyakarta Indonesia 55281

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Home Page

OAI Link

Editorial Team

Contact

Reviewer

Google Scholar

Contact Name Ari Pramudyantoro

Contact Email ajche.ft@ugm.ac.id

Phone +62274555320

Journal Mail Official ajche.ft@ugm.ac.id

Editorial Address Jln. Grafika No. 2 Kampus UGM Yogyakarta Indonesia 55281

Location Kab. sleman, Daerah istimewa yogyakarta INDONESIA

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Abstract

Contact Name
Ari Pramudyantoro

Contact Email
ajche.ft@ugm.ac.id

Phone
+62274555320

Journal Mail Official
ajche.ft@ugm.ac.id

Editorial Address
Jln. Grafika No. 2 Kampus UGM Yogyakarta Indonesia 55281

Location
Kab. sleman,

Daerah istimewa yogyakarta

INDONESIA