Judul: Isolasi Bakteri Termofil Penghasil Enzim Hidrolitik Ekstraseluler dari Sumber Air Panas Gunung Pancar
Abstrak: Delapan belas bakteri termofil aerob diisolasi dari sampel sumber air panas Gunung Pancar dengan kondisi kultivasi 70°C dan pH 7.5 pada media agar-agar Luria yang dimodifikasi (LA modifikasi). Isolat-isolat tersebut terdeteksi mempunyai aktivitas hidrolitik (proteolitik, amilolitik, kitinolitik, xilanolitik, dan lipolitik) terhadap makromolekul yang disuplementasikan pad a media LA modifikasi. Enam belas isolat tersebut menunjukkan ciri-ciri genus Bacillus, sedangkan dua isolat lainnya menunjukkan ciri-ciri Thermus. Aktivitas proteolitik dari empat isolat (GP-O I, GP-04, GI'-06, dan GI'-\ 0) tampak cukup besar pada media agar-agar susu skim. tetapi aktivitasnya rendah pada media cair, yakni hanya 0,05-0,37 unit per ml ekstrak kasar enzim. Suhu optimum aktivitas keempat protease tersebut ialah 70°C (GP-O \. GP-06, GP- 10) dan 80°C (GP- 04), sedangkan pH optimumnya ialah 7,5 (GP-O\. GI'-06, GP-IO) dan 8,5 (GP-04). Waktu paruh protease GP-04 dan GP-IO lebih dari 7,5 jam. pada suhu inkubasi 70°C. Amilase isolat GP-15 yang mirip dengan B-amilase beraktivitas optimum pada suhu 90°C, pH 8,5, dengan waktu paruhnya lebih dari 7,5 jam pada suhu inkubasi 70°C.
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Judul: Isolasi dan Seleksi Bakteri Selulolitik Termofilik dari Kawah Air Panas Gunung Pancar, Bogor
Abstrak: Cellulase has important roles in paper, textile, food, and detergent industries. Application of cellulase in industries requires the cellulase to be active and stable at high temperature. Exploration of thermophilic bacteria from crater of hot spring is one of way to obtain thermostable cellulase. The aim of this research was to isolation thermophilic bacteria which has cellulolytic activity from White and Red Crater of Mount Pancar. Cellulolytic activity was determined by ability of bacteria to degrade carboxymethyl cellulose (CMC) substrate. Cellulolytic bacteria was selected based on clear zone which form surrounding the colonies. Cellulase activity was measured by dinitrosalisilic acid (DNS) method. Growth pattern of cellulolytic bacteria was determined. Results showed that bacterial isolates from White and Red Crater of Mount Pancar able to produce cellulase. There were 8 colonies (KP1, KP2, KP3, KP4, KP5, KP6, KP7, and KP10) from white crater and 1 colony (KM1) from red crater showing ability to degrade CMC. KP4 isolate had the higest diameter ratio of clear zone and enzyme activity ( 3.8 and 6.11 x 10-3 U/mL) than KM1 isolate (1.7 and 1.17 x 10-3 U/mL). Both isolates had same growth pattern.
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Judul: Socioeconomic and psychological variables influencing household debt
Abstrak: The overall objective of this study was to examine factors influencing total debt, total debt payment, and patterns of debt payments. The study examined the impacts of both psychological (credit attitudes and perception of future income) and socioe- conomic variables on total debt, total debt payment and patterns of debt payments. A conceptual model for this study was developed by incorporating the theory of borrower risk, the economic and psychological economic theory of borrowing, and the results of previous studies. This model identifies socioeconomic and psycholog- ical variables that influence total debt, total debt payment, and patterns of debt payments. Socioeconomic variables included in the model are gender, race, mari- tal status, employment status, household size, age, education, and household assets. Psychological variables are credit attitudes toward the use of credit, and perception of future income. This study used data from the 1989 Survey of Consumer Finances. The survey was sponsored by the Federal Reserve in cooperation with some other federal agencies. Data for the survey were collected by the Survey Research Center at the University of Michigan between August 1989 and March 1990. dst ...
Keyword: Gender