ISOLATION OF LIPASE PRODUCING BACTERIA FROM HOT SPRINGS OF LONG KALI

Isolasi bakteri penghasil lipase dari sumber air panas Long Kali dilakukan dengan menyeleksi koloni bakteri pada media Nutrient Agar (NA) yang mengandung Rhodamin B dan minyak zaitun. Hasil isolasi menunjukkan 5 dari 14 isolat bakteri mampu menghasilkan lipase. lima isolat tersebut diuji aktivitas lipase dengan metode titrimetri, isolat dengan kode 14 memiliki aktivitas tertinggi dengan aktivitas 2,20 Unit/mL. Isolation of lipase producing bacteria from hot spring of Long Kali was performed by selecting bacteria colony in nutrient agar which contained rhodamine B and olive oil. Based on the results, there were 5 from 14 bacteria isolates that able to produce lipase. These five isolates were examined for their lipase activity by using titrimetry method and revealed that isolate with code of 14 showed the highest activity with activity of 2.20 Unit/m

validasi

The research about validation of the method of Hg determination on the sample from wastewater treatment plant (WWTP) PT. Badak NGL Bontang, Kalimantan Timur using cold vapour-atomic absorption spectrophotometer (CV-AAS) techniques has been conducted. To obtain a valid measurement result, determinations of the important several parameters that influence the method validation are used. The results of research showed that 20% SnCl2 solution could be used as a reducing agent. The analytic performance of measurement obtain is good, showed with the linearity (r) value ≥ 0.995, LOD was 0.2530 ppb, LOQ was 0.8432 ppb, MDL was 0.6427 ppb and repeatability and reproducibility are shown as % RSD < 2/3 CV Horwitz values. The accuracy of this method is very good with a percentage of recovery value of 114.88%. Based on the results of this research, CV-AAS method can be used in the determination of Hg in WWTP samples with the valid results.Penelitian tentang validasi metode penentuan merkuri pada sampel waste water treatment plant (WWTP) dari PT. LNG Badak Bontang, Kalimantan Timur dengan menggunakan teknik bejana uap dingin spektrofotometer serapan atom (CV-AAS) telah dilakukan. Untuk memperoleh hasil pengukuran yang valid, telah dilakukan pengukuran beberapa parameter yang berpengaruh dalam validasi metode. Hasil penelitian menunjukkan larutan SnCl2 20% dapat digunakan sebagai reduktor. Kinerja analitik pengukuran yang diperoleh sangat baik, ditunjukkan dengan nilai linearitas (r) ≥ 0,995; LOD sebesar 0,2530 ppb, LOQ sebesar 0,8432 ppb, MDL sebesar 0,6427 ppb, pengulangan dan kebolehulangan dinyatakan  sebagai %RSD < 2/3 nilai KV Horwitz. Keakuratan metode ini sangat baik dengan nilai presentase perolehan kembali sebesar 114,88%. Berdasarkan hasil penelitian ini, metode CV-AAS dapat digunakan dalam penentuan Hg pada sampel WWTP dengan hasil yang valid

Preliminary Study of Biosurfactant Consortium Producing Bacteria from Palm Oil Mill Effluent (POME) in East Kalimantan

Biosurfactants are surface active agents from living organism, especially from bacteria and fungi. Many types of biosurfactants are synthesized by a number of microbes during their growth on non-polar substrates and the majority of biosurfactants are produced by bacteria. Emulsification activity toward n-hexane, drop collapsing test as well as oil displacement test were used to determine biosurfactant producing bacteria consortium activity from palm oil mill effluent (POME). Samples were collected from waste water treatment in PTPN XIII Palm Oil Mill Factory, Paser Regency, Provincial of East Kalimantan, Indonesia. Total of six samples were screened in order to find out which consortium was producing biosurfactant. All of the samples were showing activity in the drop collapsing method, but only sample #5 and #6 were showing Emulsification activity of 50 and 14%, respectively. Moreover, sample #5 and #6 were showing oil displacement activity which have 0.37 cm and 0.26 cm in diameter, respectively.

The 8-bromobaicalein alleviated chikungunya-induced musculoskeletal inflammation and reduced the viral load in healthy adult mice

ABSTRACTChikungunya virus is a re-emerging arbovirus that has caused epidemic outbreaks in recent decades. Patients in older age groups with high viral load and severe immunologic response during acute infection are likely to develop chronic arthritis and severe joint pain. Currently, no antiviral drug is available. Previous studies suggested that a flavone derivative, 8-bromobaicalein, was a potential dengue and Zika replication inhibitor in a cell-based system targeting flaviviral polymerase. Here we characterized that 8-bromobaicalein inhibited chikungunya virus replication with EC50 of 0.49 ± 0.11 µM in Vero cells. The molecular target predicted at viral nsP1 methyltransferase using molecular binding and fragment molecular orbital calculation. Additionally, oral administration of 250 mg/kg twice daily treatment alleviated chikungunya-induced musculoskeletal inflammation and reduced viral load in healthy adult mice. Pharmacokinetic analysis indicated that the 250 mg/kg administration maintained the compound level above EC99.9 for 12 h. Therefore, 8-bromobaicalein should be a potential candidate for further development as a pan-arboviral drug

The 8-bromobaicalein inhibited the replication of dengue, and Zika viruses and targeted the dengue polymerase

Abstract Dengue and Zika viruses are mosquito-borne flaviviruses burdening millions every year with hemorrhagic fever and neurological symptoms. Baicalein was previously reported as a potential anti-flaviviral candidate and halogenation of flavones and flavanones potentiated their antiviral efficacies. Here, we reported that a chemically modified 8-bromobaicalein effectively inhibited all dengue serotypes and Zika viruses at 0.66–0.88 micromolar in cell-based system. The compound bound to dengue serotype 2 conserved pocket and inhibited the dengue RdRp activity with 6.93 fold more than the original baicalein. Moreover, the compound was mildly toxic against infant and adult C57BL/6 mice despite administering continuously for 7 days. Therefore, the 8-bromobaicalein should be investigated further in pharmacokinetics and efficacy in an animal model