25 research outputs found
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No full textVolume 14, Nomor 1. Hal. 1 – 39 Juli 2004KAJIAN PRODUKSI BIOINSEKTISIDA DARI Bacillus thuringiensis subsp israelensis PADA MEDIA TAPIOKA Abdul Aziz Darwis, Khaswar Syamsu, Ummi Salamah …………………….. 1KAJIAN STRATEGI PENINGKATAN KUALITAS TEH HITAM ORTHODOKS DI PT. PERKEBUNAN NUSANTARA VIII (PTPN VIII Persero)UNIT KEBUN GEDEH, KABUPATEN CIANJURMarimin dan Eneng Karmila ........................................................................... 6 ARANG AKTIF SEBAGAI BAHAN PENANGKAP FORMALDEHIDA PADA KAYU LAPIS Gustan Pari, Kurnia Sofyan, Wasrin Syafii dan Buchari ………………….... 17PENGARUH LAMA PENGUAPAN PELARUT (DIKLOROMETANA) DAN KONSENTRASI UMPAN TERHADAP FILTRASI SARIBUAH APEL PADA MEMBRAN SELULOSA ASETAT MIKROBIALAbdul Aziz Darwis, Proyoga Suryadarma, dan Ely Rosita …………………. 24EKSTRAKSI DAN ANALISA DIETARY FIBER DARI BUAH MENGKUDU (Morinda citrifolia)Sapta Raharja, Imam Paryanto dan Fitria Yuliani …………………………… 3
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No full textVolume 14, Nomor 1. Hal. 1 – 39 Juli 2004KAJIAN PRODUKSI BIOINSEKTISIDA DARI Bacillus thuringiensis subsp israelensis PADA MEDIA TAPIOKA Abdul Aziz Darwis, Khaswar Syamsu, Ummi Salamah …………………….. 1KAJIAN STRATEGI PENINGKATAN KUALITAS TEH HITAM ORTHODOKS DI PT. PERKEBUNAN NUSANTARA VIII (PTPN VIII Persero)UNIT KEBUN GEDEH, KABUPATEN CIANJURMarimin dan Eneng Karmila ........................................................................... 6 ARANG AKTIF SEBAGAI BAHAN PENANGKAP FORMALDEHIDA PADA KAYU LAPIS Gustan Pari, Kurnia Sofyan, Wasrin Syafii dan Buchari ………………….... 17PENGARUH LAMA PENGUAPAN PELARUT (DIKLOROMETANA) DAN KONSENTRASI UMPAN TERHADAP FILTRASI SARIBUAH APEL PADA MEMBRAN SELULOSA ASETAT MIKROBIALAbdul Aziz Darwis, Proyoga Suryadarma, dan Ely Rosita …………………. 24EKSTRAKSI DAN ANALISA DIETARY FIBER DARI BUAH MENGKUDU (Morinda citrifolia)Sapta Raharja, Imam Paryanto dan Fitria Yuliani …………………………… 3
Purifikasi dan Karakterisasi α-amilase Termostabil dari Bacillus stearothermophilus TII-12
Full text link<p>Purification and Characterization of Thermostable<br />α-amylase from Bacillus stearothermophilus TII-12. Puji<br />Lestari, Nur Richana, Abdul A. Darwis, Khaswar Syamsu,<br />and Untung Murdiyatmo. Thermostable α-amylase is a<br />potential enzyme employed in the starch processing and<br />widely used in food industries, but this enzyme is still<br />imported. The local enzyme production would be more<br />economist and useful for its broad applications. Here we<br />report α-amylase from indigenous bacteria TII-12 which was<br />purified and characterized, as well as analyzed its hydrolysis<br />product on cassava starch. The enzyme of Bacillus<br />stearothermophilus TII-12 partially purified by ultrafiltration,<br />acetone precipitation and gel filtration (Sephadex G-100)<br />showed the reduced total activity, total protein and yield, but<br />increased the specific activity. The enzyme had a Km of 1,06<br />mg/ml and Vmax of 1,21 mol/min, with optimal activity at pH 7<br />and 90oC. An apparent molecular mass was of 192.932,8<br />Dalton, as estimated by Native-Polyacrylamide Agarose Gel<br />electrophoresis. Its activity was inhibited by the divalent<br />cation chelator such as EDTA and CuSO4 but activated by<br />calcium ion. Hydrolysis products of this enzyme on cassava<br />starch were glucose, dextrin, maltose and oligosaccharides.<br />After 24 hours of hydrolysis, the concentration of glucose<br />and maltose reached 51.970 and 10.090 ppm, respectively.<br />The thermostable α-amylase of TII-12 is an endo-α-amylase<br />and prospective to be applied on starch liquefaction with<br />high temperature process.</p></jats:p
Pengaruh Nisbah Pereaksi (Lignin Eupcalyptus – Natrium Bisulfit) Dan Ph Awal Reaksi Sulfonasi Terhadap Karakteristik Natrium Lignosulfonat
Full text linkEucalyptus lignin was isolated from kraft black liquor through by acidification using H2SO4. Sulfonation of eucalyptus lignin produced sodium lignosulfonate (SLS) which can be used as dispersants, and emulsifier. In this research, sulfonation was carried out towards lignin with mass ratio of eucalyptus lignin-NaHSO3 (b/b) of 1:0.4, 1:0.5, and 1:0.6, and initial pH of 5, 6, 7, 8. Studies on the effect of various ratio of eucalyptus lignin versus NaHSO3 (1 based on w/w) and initial pH of 5,6,and 7 for the sulfonation reaction showed an increasing yield and improved purity of SLS obtained. However, no significant result was observed on the application of initial pH 7 and 8 toward increasing of SLS yield and purity. The highest SLS yield of 83.8% with purity of 82.9% was obtained under condition of initial pH at 7 and the mass ratio of eupcayptus lignin over NaHSO3 was 1:0.5. The resulted SLS was light brown, water soluble, with pH level between 6.3 and 7.24, and released sulfur-like odor
The Influence Of Reactant Ratio (Eupcalyptus Lignin – Sodium Bisulfite) And Initial Ph Towards Characteristcs Of Sodium Lignosulfonate
Full text linkEucalyptus lignin was isolated from kraft black liquor through by acidification using H2SO4. Sulfonation of eucalyptus lignin produced sodium lignosulfonate (SLS) which can be used as dispersants, and emulsifier. In this research, sulfonation was carried out towards lignin with mass ratio of eucalyptus lignin-NaHSO3 (b/b) of 1:0.4, 1:0.5, and 1:0.6, and initial pH of 5, 6, 7, 8. Studies on the effect of various ratio of eucalyptus lignin versus NaHSO3 (1 based on w/w) and initial pH of 5,6,and 7 for the sulfonation reaction showed an increasing yield and improved purity of SLS obtained. However, no significant result was observed on the application of initial pH 7 and 8 toward increasing of SLS yield and purity. The highest SLS yield of 83.8% with purity of 82.9% was obtained under condition of initial pH at 7 and the mass ratio of eupcayptus lignin over NaHSO3 was 1:0.5. The resulted SLS was light brown, water soluble, with pH level between 6.3 and 7.24, and released sulfur-like odor.Key words: lignin, kraft black liquor, sodium lignosulfonate
KAJIAN PRODUKSI BIOINSEKTISIDA DARI Bacillus thuringiensis subsp israelensis PADA MEDIA TAPIOKA
Full text linkABSTRACTBacillus thuringiensis subsp israelensis (B.t.i) as one of the Bacillus thuringiensis (B.t) species produces crystal protein called delta endotoxin. As other B.t crystal protein, this crystal is specifically toxic to mosquitoes and blackflies. This research of B.t.i fermentation used tapioca as carbon source and urea as nitrogen source. The composition of media fermentation used were 0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0% of tapioca, and 1% urea. The result shows that B.t.i was able to grow in all treatment units. Bioassay shows that the best performance was obtained from media with 2.0% tapioca.Key words: Bacillus thuringiensis, tapioc
Lipid Biotechnology of Palm Oil for the Production of Basic Oleochemicals : Kinetics of Enzymatic Hydrolysis of Palm Oil by Lipase from Candida cylindracea in the Absence of Emulsifier and Buffer
Full text linkIndonesia is the second largest world exporters of palm oil after Malaysia, constituting about 20 % of total world supply of palm oil. Development programs which have been carried out by the Indonesian government through intensification and extensification of oil palm estates are expected to strengthen the position of Indonesia in the supply of palm oil and palm oil products in the near future. The palm oil has a wide range of applications, i.e. for food as well as industrial purposes, therefore the development of palm oil industries has a positive impact in terms of economic development of this country. Basic oleochemicals are among many high - value specialty products which can be produced from fat/oil by enzymatic process. Basic oleochemicals are becoming strategic commodities due to fast development of health care, cosmetics and pharmaceutical industries. This study is aimed to develop a system of enzymatic hidrolysis of palm oil by lipase in the absence of emulsifier and buffer to produce basic oleochemicals. The enzymatic reaction of Michaelis - Menten type that occured at the interface between oil and aqueous phases was assumed in deriving the rate equations. The effect of water on equilibria has been ignored for hydrolase reactions in an aqueous phase, therefore equations corresponding to a - one substrate, one - order irreversible model are derived and used for analysis. The progress curves predicted from the conversion equations agreed very well with the experimental results under various reaction conditions. The methodology presented in this work might be used to find kinetic parametes for reactor design and scale-up. Activity of the lipase showed no apparent change between 35 and 40°C, but increased with temperature between 30 and 35°C. When the substrate concentration was higher than 0.3660 g/ml, the equilibrium fractional conversion value of hydrolysis decreased as the concentration of substrate increased. The Michaelis constant gradually decreased with increasing stirring speed between 200 and 400 rpm, and decreased slowly with stirring speed between 400 and 1000 rpm. Equilibrium fractional conversion changed when water was added during the hydrolysis reaction, and reached maximum when water was added after 120 minutes reaction
