Claim Missing Document
Check
Articles

Found 28 Documents
Search

KARAKTERISASI FILM KOMPOSIT ALGINAT DAN KITOSAN Nur Rokhati; Bambang Pramudono; Nyoman Widiasa; Heru Susanto
Reaktor Volume 14, Nomor 2, Oktober 2012
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (517.1 KB) | DOI: 10.14710/reaktor.14.2.158-164

Abstract

CHARACTERIZATION OF ALGINATE AND CHITOSAN COMPOSITE FILM. Due to the specific characteristics of (thin) films, the use of polymer films in various aplications has singnificantly increased. Alginate and chitosan are natural polymers, which have potential as a raw material for the manufacture of composite films. This paper presents the preparation and characterization of alginate, chitosan and chitosan-alginate composite films. The film characterization included permeability test, degree of swelling, mechanical property, morphology (by SEM), and surface chemistry (by FTIR). The results showed that alginate films have a higher permeability ​​and degree of swelling (DS) than chitosan films. Both permeability and DS decreased with increasing concentration for both alginate and chitosan films. DS experiments showed that the films have the highest DS in water followed by ethanol 95% and ethanol >99.9%, respectively. The mechanical strength of chitosan films was larger than alginate films. Alginate-chitosan composite films prepared by layer by layer method showed better characteristics than the composite films prepared by blending of alginate and chitosan solutions. Meningkatnya aplikasi film polimer di berbagai industri tidak terlepas dari keunggulan yang dimiliki. Alginat dan kitosan merupakan polimer alam yang mempunyai potensi sebagai bahan dasar pembuatan film komposit. Pada penelitian ini dilakukan pembuatan dan karakterisasi film komposit berbasis alginat dan kitosan. Karakterisasi film yang dilakukan meliputi uji: permeabilitas, derajat swelling, mekanik, morfologi (dengan SEM), dan struktur kimia permukaan (dengan FTIR). Hasil penelitian menunjukkan bahwa film alginat mempunyai nilai permeabilitas maupun derajat swelling yang lebih tinggi dibanding dengan film kitosan. Baik pada kitosan maupun alginat memberikan fenomena bahwa semakin besar konsentrasi larutan maka semakin kecil nilai permeabilitas maupun derajat swelling, dengan derajat swelling terhadap air adalah yang  paling besar kemudian diikuti oleh ethanol teknis (± 95%) dan yang terkecil adalah ethanol PA (> 99,9%). Kekuatan mekanik film kitosan lebih besar dibanding dengan film alginat. Film komposit alginat-kitosan yang dibuat dengan metode layer by layer memberikan karakteristik yang lebih baik dibanding dengan film komposit yang dibuat dengan pencampuran larutan alginat dan larutan kitosan.
DEPOLIMERISASI KITOSAN DENGAN HIDROLISA ENZIMATIK MENGGUNAKAN ENZIM α-AMILASE Hanik Handayani P.L.; Paramarta Siwi R.; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 4, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (249.973 KB)

Abstract

Chitosan is a polymer derivative of chitin that has many benefits in food and medical. Since chitosan has a large molecular weight, it has constraints to its application. To overcome the disadvantage, it needs hydrolysis of chitosan in order to obtained a lower molecular weight. In this research the hydrolysis of chitosan will  be operated by enzymatic process uses thermophilic enzyme α-amylase. The experiment begins by making a chitosan solution 1% w/v in an acetic acid solution 1% v/v. The chitosan solution is hydrolyzed using the enzyme α-amylase with varied pH, operating temperature, time, and ratio of the enzyme:substrate to obtain the optimum. The response comprehends Dextrose Equivalent (DE), viscosity, and the average of molecular weight. The results showed that the optimum operating conditions for chitosan hydrolysis using α-amylase enzyme is at pH 5, temperature 90 °C, 2 hours operating time, and ratio of enzyme:substrate 1:2500 (0,1 ml). For variable pH, temperature, time, and enzyme addition, DE rises meanwhile variables are increased, then it dropped significantly after the optimum level. The hydrolysis can reduce molecular weight of chitosan from 1680-1750 kDa to 144,18 kDa thus it is included to MMWCs.
HIDROLISIS KITOSAN MENGGUNAKAN KATALIS ASAM KLORIDA (HCl) Irsan Adhiatama; Muhamad Zainudin; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (244.472 KB)

Abstract

The molecular weight is an important factor in the application of chitosan. High molecular weight will restrict the use of chitosan. This research uses a chemical process with acid hydrolysis. Hydrolysis is de-polymerization to lower molecular weight that occur because of the termination of glycoside bond by reaction with water (H2O). De-polymerization of chitosan is different from other polysaccharide compounds, because its have a difficult decomposed β-bond and a cationic amine groups. Therefore, it required operating conditions and type of catalyst to produce chitosan in accordance with specifications. The purpose of this research is to obtain optimum conditions of chitosan hydrolysis process and determine the type of acid catalyst is best to produce chitosan with low molecular weight (LMWCs). Results showed that temperature, catalyst concentration, and type of catalyst greatly affect on the depolymerization of chitosan. Depolymerization effect increases with increasing temperature and catalyst concentration, characterized by reduced viscosity and molecular weight of chitosan. To produce chitosan with a molecular weight between 50-100 kDa, optimum conditions : temperature of 70 0C, hydrolysis time 120 minutes, and the concentration of Hidrochloric Acid (HCl )was 0.6 to 0.8 N.
PENGARUH COATING ALGINATE-CHITOSAN TERHADAP PERTUMBUHAN MIKROBA PADA BUAH MELON KUPASAN Heru Cahyana; Marcelinus Christwardana; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (83.541 KB)

Abstract

Lack of peeling fruit processing now cause the rapid spoilage the fruit. Therefore, most of the industry slows microbial growth by using a coating on the fruit. In this study making edible films made from alginate and chitosan. Edible film also applied to peeling melon and tested the microbial growth during 3 days. The result showed melon which coating with chitosan film is very good because this film can hold up during 2 days with growth of microbe to 21,6 x 105 CFU/gr.
PENGARUH COATING ALGINATE-CHITOSAN TERHADAP PERTUMBUHAN MIKROBA PADA BUAH MELON KUPASAN Heru Cahyana; Marcelinus Christwardana; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1566.329 KB)

Abstract

Lack of peeling fruit processing now cause the rapid spoilage the fruit. Therefore, most of the industry slows microbial growth by using a coating on the fruit. In this study making edible films made from alginate and chitosan. Edible film also applied to peeling melon and tested the microbial growth during 3 days. The result showed melon which coating with chitosan film is very good because this film can hold up during 2 days with growth of microbe to 21,6 x 105 CFU/gr.
PENGARUH KONSENTRASI KITOSAN TERHADAP PROSES FLOKULASI PADA PEMANENAN MIKROALGA Rangga Warsita Aji; Wulan Sari Gusniawati; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (512.957 KB)

Abstract

The common method used for harvesting microalgae is filtration. But, it has disadvantages such as particle size of microalgae are generally small causing the harvesting process uneffecient. It can be measure using chitosan as bioflocculant. The first procedure of research is making a stock solution of chitosan was prepared by dissolving chitosan flakes in 1% (v/v) acetic acid until the flakes was totally dissolved, then  it is introduced  into 500 ml of microalgae culture (Spirulina sp). The flocculation process is experimental designed by the variation of the concentration of chitosan (5 mg/L ; 10 mg/L ; 15 mg/L ; 40 mg/L ; 70 mg/L ; 100 mg/L) at pH 8 and slow mixing speed 40 rpm.  The result shows that increasing concentration of chitosan causes increasing flocculation efficiency but at the concentration that is too high, it will make flocculation efficiency decrease.
PENGARUH KONSENTRASI SERTA PENAMBAHAN GLISEROL TERHADAP KARAKTERISTIK FILM ALGINAT DAN KITOSAN Giovanni Anward; Yusuf Hidayat; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 3, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (277.978 KB)

Abstract

Bioethanol used as fuel should have purity greater than 99.5%, but the conventional distillation produces only 95% purity. One way to increase the purity of ethanol is pervaporation method using selective membrane. The aim of this research is to prepare and characterize alginate and chitosan films. To determine the optimum concentration of alginate and chitosan films, both of these films were characterized. The results showed that the optimum alginate film obtained at 3% of concentration with the addition of 20% glycerol, while the optimum chitosan film obtained at 3% of concentration without the addition of glycerol. Alginate film has the highest permeability and swelling degree, while chitosan film has the lowest value. Alginate and chitosan films have the highest swelling degree in water, then 95% alcohol and the lowest is in PA alcohol.
PEMANFAATAN MINYAK GORENG BEKAS DAN ABU KULIT BUAH KAPUK RANDU (SODA QIE) SEBAGAI BAHAN PEMBUATAN SABUN MANDI ORGANIK BERBASIS TEKNOLOGI RAMAH LINGKUNGAN Naliawati Prastiya Ningrum; Muhamad Alfin Indra Kusuma; Nur Rokhati
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 2, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (972.522 KB)

Abstract

Capok Randu (Ceiba petandra (L)) Gaerin van Indica (D.C) are most everseen in Indonesia mainly as horticulture in Central Java, with the total areas of95.107,17 ha. Manufacture of capok randu’s ash leather called Soda Qie and itcontains 78%W of potassium. In the other hand, consumption of frying oil inIndonesia is very high and it increases annually, up to 500.000 tons/year. Ex fryingoil produced still contains plenty of free fatty acid and it can be used as raw materialin preparation of soap with soda qie as a source of alkaly by saponification reaction.This experiment aimed to find the optimum operation condition in soap preparationand the its reaction kinetic. This experiment is designed using RSM method (ResponseSurface Methodology) and software Statistica 6. Parameters in this research are exfrying oil volume of 100 ml, soda qie solution concentration of 300 g / 1000 ml, andsaponification reaction time of 60 minutes. Independent variables are the reaction temperature of 30, 60, 90 oC, ratio of soda qie volume : ex frying oil volume 3:1 ; 4:1; 5:1 ml. Optimation is conducted at saponification reaction time variables of 30, 60,90, 120 minutes. Observed responses are amount of Free Fatty Acid (FFA), and freealkali of the product. The optimum operation condition are gained at temperatur of90oC, reactant ratio of 3:1. In the soap product, the number of FFA are 0,80%, andthe number of free alkali are 0,08%, this is fulfill the SII.0005-72. The rate constantgained were 0,068 menit-1.
Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme Nur Rokhati; Bambang Pramudono; Titik Istirokhatun; Heru Susanto
Bulletin of Chemical Reaction Engineering & Catalysis 2018: BCREC Volume 13 Issue 3 Year 2018 (December 2018)
Publisher : Department of Chemical Engineering - Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (493.463 KB) | DOI: 10.9767/bcrec.13.3.2378.466-474

Abstract

The influence of microwave irradiation on the chitosan hydrolysis catalyzed by cellulase enzyme was studied. The hydrolyzed chitosan was characterized by measuring its viscosity and reducing sugar. Further, it was also characterized by Fourier-Transform Infrared Spectroscopy (FT-IR), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM). The classical Michaelis-Menten kinetic parameters were measured by analyzing the amount of reducing sugars. The results were compared with the hydrolysis by using conventional shaker incubator. The hydrolysis reaction time needed to obtain similar reducing sugar yield was significantly lower for microwave irradiation than shaker incubator. On the other hand, the reduction rate of the relative viscosity was significantly higher for the hydrolysis of chitosan using shaker incubator. A significant difference in chemical structure was observed between hydrolysis using microwave irradiation and shaker incubator. Overall, the result showed that the hydrolysis behavior of chitosan using microwave irradiation is significantly different with using shaker incubator.  
Pengaruh Pretreatment Iradiasi Microwave pada Hidrolisis Kitosan dengan Enzim Cellulase Nur Rokhati; Bambang Pramudono; Mohammad Sulchan; Anggara Eka Permana; Suryo Tetuko
Jurnal Aplikasi Teknologi Pangan Vol 6, No 1 (2017): Februari 2017
Publisher : Indonesian Food Technologists

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (512.002 KB) | DOI: 10.17728/jatp.212

Abstract

Kitosan merupakan polimer alam yang diperoleh dari proses deasetilasi kitin yang terkandung di dalam cangkang binatang invertebrata terutama crustacea seperti udang dan rajungan. Karena sifatnya yang biocompatible, biodegradable, bioaktivitas, dan tidak beracun, kitosan telah digunakan secara luas dalam berbagai bidang seperti pangan, nutrisi, farmasi, medis, dan pertanian. Kitosan memiliki berat molekul yang tinggi, viskositas tinggi, dan kelarutan di dalam air yang rendah, sehingga akan menghambat aplikasinya. Salah satu metode yang umum dilakukan untuk menurunkan berat molekul kitosan adalah hidrolisis enzimatis. Kelemahan dari metode ini adalah laju reaksi yang lambat. Penelitian ini bertujuan untuk mengkaji pretreatment iradiasi microwave pada hidrolisis enzimatis kitosan. Hasil penelitian menunjukkan bahwa pretreatment iradiasi microwave dapat meningkatkan laju penurunan berat molekul dan viskositas larutan kitosan. Hidrolisis kitosan dengan pretreatment iradiasi microwave pada power 120 watt selama 9 menit dapat meningkatkan kelarutan kitosan dalam air dari 0,02% menjadi 0,26% (berat/volume). Analisis FTIR menunjukkan bahwa struktur kimia produk hidrolisis mirip dengan kitosan awal.Chitosan is a natural polymer obtained from the deacetylation of chitin contained in shells of invertebrates, especially crustaceans such as shrimp and crab. Because it is biocompatible, biodegradable, bioactivity, and non-toxic, chitosan has been widely used in various fields such as food, nutritional, pharmaceutical, medical, and agriculture. Chitosan has a high molecular weight, high viscosity, and solubility in water is low, so it will hamper application. One common method to lower the molecular weight of chitosan is the enzymatic hydrolysis. The disadvantage of this method is the reaction rate is slow. This study aims to assess the microwave irradiation pretreatment on enzymatic hydrolysis of chitosan. The results showed that pretreatment microwave irradiation can increase the rate of decrease in molecular weight and viscosity of chitosan solution. Pretreatment of chitosan hydrolysis with microwave irradiation at 120 watts power for 9 minutes can increase the solubility of chitosan in water from 0,02% to 0,26% (weight / volume). FTIR analysis showed that the hydrolysis products of the chemical structure is similar to the initial chitosan.