Pembentukan biofilm oleh bakteri filamentous yang tumbuh pada medium cair mengandung merkuri anorganik (HgCl2)=Production of biofilm by filamentous bacteria grown on liquidmedium ...

• Main Author: Perpustakaan UGM, i-lib
• Format: Article NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2006
• Subjects: Jurnal i-lib UGM
• Online Access: https://repository.ugm.ac.id/17776/; http://i-lib.ugm.ac.id/jurnal/download.php?dataId=542
• Institution: Universitas Gadjah Mada

ABSTRACT: Mercury residues released in the environtment had a potency as pollutant from a traditional gold mine industry. Mercury was a toxic heavy metal that could cause bacteria to become resistant or died. Only several spesies of particullarly filamentous bacteria were able to use mercury as an energy source. This research aims were to obtain resistant filamentous bacteria against mercury and to study formation biofilm on liquid medium containing mercury (HgC12). The research was commenced with isolating bacteria from sediments of Sangon river through a batchwise enrichment culture techniques using modified nutrient broth containing 0,5 mg1-1 HgC12. Filamentous bacteria were isolated after several subcultures using pour plate techniques. The isolates were selected based on their capability of growing on liquid growth medium containing different concentrations of mercury. The bacterial film formation of selected isolates carried out through the cultivation experiments at an interval of time bacterial growth and biofilm formation were observed spectrofotometrycally (OD 600 nm and 490nm) respectively. The bacterial activity was determined based on their ability to accumulate mercury, poliacrylarnide (SDS-PAGE) methods. The selected bacteria were identified using standard methods. The experiment results revealed that polluted Sangon river sediments by mercury were predominated by filamentous bacteria. Sixteen types of bacteria were successfully isolated through enrichment culture techniques. Three of those isolates were able to grow at generation times (g) of 1,04h - 5,5h and specific growth rates (p) of 0,11 - 0,31h-I on medium containing 4 mg1-1 HgC12. Anorganic mercury (HgC12) stimulated the formation biofilm that_ enabled mercury to be accumulated. The total of mercury accumulated on the three bacterial cultures was about 50, 106, 127 ngg-1(wet weight) biomass. The bacterial activity on the polia-crylarnide gel was demonstrated as white band proteins with molecular weight of 59,57 - 64,81 kDa. The proteins were assumed as mercury reductases. Three selected isolates were identified as Acinetobacter sp. strain BF03, Acinetobacter sp. strain BF04 and Bacillus sp. strain BF08. Keyword : filamentous bacteria, biofilm formation, resistant, anorganic mercury