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PENGARUH DERAJAT DEASETILASI KHITOSAN DARI KULIT UDANG TERHADAP APLIKASINYA SEBAGAI PENGAWET MAKANAN Rokhati, Nur
Reaktor Volume 10, Nomor 2, Desember 2006
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (151.483 KB) | DOI: 10.14710/reaktor.10.2.54-58

Abstract

Industri pengolahan udang banyak menimbulkan hasil samping berupa limbah kulit udang yang belum dimanfaatkan secara optimal, yaitu hanya dijadikan tepung dan campuran makanan ternak. Hal itu kurang memiliki nilai ekonomis dibandingkan dengan mengolahnya menjadi khitin dan khitosan. Khitosan banyak digunakan di berbagai industri. Salah satu penerapan khitosan yang penting dan dibutuhkan dewasa ini adalah sebagai pengawet bahan makanan pengganti formalin. Kualitas khitosan sering dinyatakan dengan besarnya nilai derajad deasetilasi. Penelitian ini bertujuan untuk menentukan kondisi operasi optimum proses deasetilasi khitin serta mempelajari pengaruh derajat deasetilasi terhadap khitosan sebagai bahan pengawet makanan. Proses deproteinisasi dengan larutan NaOH (3.5 % w/v) selama 2 jam pada suhu 65 oC dan proses demineralisasi dalam larutan HCl (1N) selama 30 menit pada suhu kamar. Proses deasetilasi dilakukan dengan memanaskan khitin dengan larutan NaOH (20%, 30%, 40%, 50%, 60%, 70%, 80% w/v) pada suhu (50 oC, 60 oC, 70 oC, 80 oC, 90 oC, 100 oC, 110 oC) selama (1, 2, 3, 4, 5, 6, 7 jam). Parameter respon adalah derajat deasetilasi khitosan. Produk khitosan diaplikasikan untuk pengawet tahu dan analisa mikroba dilakukan dengan menggunakan metode TPC untuk mengetahui pengaruh derajat deasetilasi terhadap kemampuannya mengawetkan makanan. Hasil penelitian menunjukkan bahwa kondisi optimum proses deasetilasi khitin  menjadi khitosan adalah pada konsentrasi NaOH 50% dan suhu 100oC selama 1 jam yang memberikan derajat deasetilasi sebesar 71,2%.. Total bakteri pada perendaman tahu selama 3 hari dalam larutan asam asetat ditambah chitosan 6,8.104, dalam larutan asam asetat saja 9,9. 105, dan dalam blangko 8,6. 107, sehingga bisa disimpulkan bahwa khitosan dapat menghambat pertumbuhan bakteri. Namun meningkatnya derajad deasetilasi tidak begitu berpengaruh terhadap penurunan jumlah bakteri.
DEPOLIMERISASI KITOSAN DENGAN HIDROLISA ENZIMATIK MENGGUNAKAN ENZIM α-AMILASE P.L., Hanik Handayani; R., Paramarta Siwi; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 4, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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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 ?-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 ?-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 ?-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.
LAYER BY LAYER COMPOSITE MEMBRANES OF ALGINATE-CHITOSAN CROSSLINKED BY GLUTARALDEHYDE IN PERVAPORATION DEHYDRATION OF ETHANOL Rokhati, Nur; Istirokhatun, Titik; Samsudin, Asep Muhamad
International Journal of Renewable Energy Development Vol 5, No 2 (2016): July 2016
Publisher : Center of Biomass & Renewable Energy, Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (802.193 KB) | DOI: 10.14710/ijred.5.2.101-106

Abstract

Hydrophilicity of membrane causing only water can pass through membrane. Pervaporation process using organophilic membrane has been offered as alternative for ethanol dehydration. This paper investigate pervaporation based biopolymer composite membrane from alginate-chitosan using layer by layer method prepared by glutaraldehyde as crosslinking agent and polyethersulfone (PES) as supported membrane. Characterization of crosslinked of composite membrane by FTIR helped in identification of sites for interaction between layers of membrane and support layer (PES). The SEM showed a multilayer structure and a distinct interface between the chitosan layer, the sodium alginate layer and the support layer. The coating sequence of membranes had an obvious influence on the pervaporation dehydration performance of membranes. For the dehydration of 95 wt% ethanol-water mixtures, a good performance of PES-chitosan-alginate-chitosan (PES/Chi/Alg/Chi) composite membrane was found in the pervaporation dehydration of ethanol. Article History: Received April 12nd , 2016; Received in revised form June 25th , 2016; Accepted July 1st , 2016; Available onlineHow to Cite This Article: Rokhati, N., Istirokhatun, T. and Samsudin, A.M. (2016) Layer by Layer Composite Membranes of Alginate-Chitosan Crosslinked by Glutaraldehyde in Pervaporation Dehydration of Ethanol. Int. Journal of Renewable Energy Development, 5(2), 101-106.http://dx.doi.org/10.14710/ijred.5.2.101-106 
INFLUENCE OF MICROWAVE IRRADIATION ON EXTRACTION OF CHITOSAN FROM SHRIMP SHELL WASTE Apriyanti, Dwi Titik; Susanto, Heru; Rokhati, Nur
Reaktor Volume 18 No. 1 March 2018
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (417.081 KB) | DOI: 10.14710/reaktor.18.1.45-50

Abstract

Chitosan is natural polysaccharides which is nontoxic, biodegradable, and biocompatible and have many advantages in various kinds of fields including health, food, agriculture, and industry. Chitosan usually take long time to extract by conventional method for deacetylation process of chitin. Raw material for chitosan can be found in shrimp shell waste. Chitosan manufactures usually need high temperatures and chemicals in large quantities and it takes much time and consumes a lot of energy where will give bad effect to the environment. Recently microwave irradiation as nonconventional energy sources is widely used in chemical reactions. To reduce the impact of environmental pollution due to excessive use of chemical treatment, the objective of this work is processing chitosan under microwave irradiation. Expected production of chitosan with the same mass requires fewer chemicals than conventional heating. In particular, the study will examine the effect of making the chitosan and adding chemicals, reaction time and operating temperature and degree of deacetylation in chitosan with conventional heating methods that the results will be compared using a microwave. In this research will be developed to the design and fabrication of prototype scale extractor for manufacturing chitosan from shrimp shell waste after optimum results obtained from the research laboratory scale. From the research we can conclude that microwave will speed up reaction time. FTIR also showed functional group of chitosan formed from microwave irradiation have same results.  Keywords: chitosan, shrimp shells, microwave
PENGARUH KONSENTRASI KITOSAN TERHADAP PROSES FLOKULASI PADA PEMANENAN MIKROALGA Warsita Aji, Rangga; Gusniawati, Wulan Sari; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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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 COATING ALGINATE-CHITOSAN TERHADAP PERTUMBUHAN MIKROBA PADA BUAH MELON KUPASAN Cahyana, Heru; Christwardana, Marcelinus; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 1, Nomor 1, Tahun 2012
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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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 SERTA PENAMBAHAN GLISEROL TERHADAP KARAKTERISTIK FILM ALGINAT DAN KITOSAN Anward, Giovanni; Hidayat, Yusuf; Rokhati, Nur
JURNAL TEKNOLOGI KIMIA DAN INDUSTRI Volume 2, Nomor 3, Tahun 2013
Publisher : Jurusan Teknik Kimia, Fakultas Teknik, Universitas Diponegoro,

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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.
Produksi Glukosamin melalui Hidrolisis Kitosan Menggunakan Irradiasi Microwave Rokhati, Nur; Istirokhatun, Titik; Marpaung, Reisa Novita; Utomo, Ananda Dwi
Prosiding Seminar Nasional Teknik Kimia "Kejuangan" 2017: PROSIDING SNTKK
Publisher : Prosiding Seminar Nasional Teknik Kimia "Kejuangan"

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Abstract

Glucosamine (2-amino-2-deoxy-glucose) is an amino-monosaccharide from chitosan, which has many usesin the field of health, especially for the joints, bones, and teeth. Glucosamine can be obtained by the completehydrolysis of chitosan. The influence of microwave irradiation on the chitosan hydrolysis with catalyzed byhydrochloric acid was studied. The hydrolyzed chitosan was characterized by reducing sugar measurement,and FT-IR analysis. The results were compared between hydrolysis using conventional heating andmicrowave irradiation. Microwave irradiation can increase the reaction rate of glucosamine formation.Under the condition of microwave irradiation, the yield of glucosamine is 72.67% after 20 min hydrolysis.While to obtain yield glucosamine 70% required 2 hours for hydrolysis using conventional heating.Chemical structure by FTIR and the reducing sugar content of the glucosamine produced not different withthe glucosamine purchased from Sigma-Aldrich.
Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme Rokhati, Nur; Pramudono, Bambang; Istirokhatun, Titik; Susanto, Heru
Bulletin of Chemical Reaction Engineering & Catalysis 2018: BCREC Volume 13 Issue 3 Year 2018 (SCOPUS and Web of Science Indexed, 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. Copyright © 2018 BCREC Group. All rights reservedReceived: 19th March 2018; Revised: 19th June 2018; Accepted: 25th June 2018How to Cite: Rokhati, N., Pramudono, B., Istirokhatun, T., Susanto, H. (2018). Microwave Irradiation-Assisted Chitosan Hydrolysis Using Cellulase Enzyme. Bulletin of Chemical Reaction Engineering & Catalysis, 13 (3): 466-474 (doi:10.9767/bcrec.13.3.2378.466-474)Permalink/DOI: https://doi.org/10.9767/bcrec.13.3.2378.466-474 
HIDROLISIS ENZIMATIK KITOSAN DENGAN KOMBINASI ENZIM ENDO-GLUCANASE DAN CELLOBIOHYDROLASE Rokhati, Nur; Pramudono, Bambang; Istirokhatun, Titik; Sulchan, Mohammad; Kresnianingrum, Dyah Ayu; Dewi, Luthfi Kurnia
Reaktor Volume 15 No.4 Oktober 2015
Publisher : Dept. of Chemical Engineering, Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (568.317 KB) | DOI: 10.14710/reaktor.15.4.261-267

Abstract

Abstract CHITOSAN ENZYMATIC HYDROLYSIS USING A COMBINATION OF ENDO-GLUCANASE AND CELLOBIOHYDROLASE. Chitosan is very promising in various fields including medicine, pharmacology, and the food industry. However, the application of this polysaccharide is limited by its high molecular weight resulting in its low solubility in aqueous media. In this respect, the chitosan with shorter chain length, display a reduced viscosity and are soluble in aqueous media at pH values close to neutrality. The aim of this study is the hydrolysis of chitosan to obtain a low molecular weight chitosan using enzymes endo-glucanase and cellobiohydrolase. The hydrolysis of chitosan was carried out under a temperature of 40° C and pH 5. Chitosan degradation was monitored by the analysis of reducing sugars and viscosity, whereas the chemical characterization of chitosan is done by using test FTIR (infrared spectroscopy). The results showed that enzyme treatment resulted in a substantial loss in viscosity of the chitosan solution shows depolymerization. Depolymerization using endo-glucanase took place very quickly during the initial 15 minutes. The rate of viscosity decrease on chitosan degradation using cellobiohydrolase is lower than using endo-glucanase. When the reaction time was 4 h, the lowest  viscosity is showed by cellobiohydrolase, and the highest solubility is showed by combination of endo-glucanase and cellobiohydrolase. Keywords: endo-glucanase; cellobiohydrolase; chitosan; hydrolysis Abstrak Kitosan dapat dimanfaatkan di berbagai bidang seperti kedokteran, farmasi dan industri makanan. Aplikasi kitosan sering dibatasi oleh berat molekul kitosan yang tinggi sehingga viskositasnya tinggi dan kelarutannya rendah. Kitosan dengan rantai polimer pendek, akan mempunyai viskositas rendah, dan mudah larut pada larutan/air dengan pH mendekati netral. Penelitian ini bertujuan untuk menghidrolisis kitosan secara enzimatis menggunakan enzim endo-glucanase dan cellobiohydrolase. Hidrolisis kitosan dilakukan pada suhu 40 °C dan pH 5. Degradasi kitosan dipantau melalui analisa gula reduksi dan viskositas, sedangkan karakterisasi kimia kitosan dilakukan dengan menggunakan uji FTIR (infra red spectroscopy). Hasil penelitian menunjukkan bahwa hidrolisis enzimatis kitosan dapat menyebabkan terjadinya penurunan berat molekul yang ditandai dengan adanya penurunan viscositas larutan kitosan. Pada 15 menit awal hidrolisis terjadi penurunan viskositas yang sangat besar. Laju penurunan viskositas enzim cellobiohydrolase lebih rendah dibanding dengan enzime endo-glucanase. Setelah waktu reaksi 4 jam, viskositas terendah diperoleh pada enzime cellobiohydrolase, sedangkan kelarutan tertinggi diperoleh pada kombinasi enzime endo-glucanase dan cellobiohydrolase. Kata kunci: endo-glucanase; cellobiohydrolase; kitosan; hidrolisis