cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Ivandini Tribidasari A.
Contact Email
ivandini.tri@sci.ui.ac.id
Phone
+622129120943
Journal Mail Official
editor_mss@ui.ac.id
Editorial Address
Directorate of Research and Community Engagement UNIVERSITAS INDONESIA UI Campus, Depok 16424 Indonesia
Location
Kota depok,
Jawa barat
INDONESIA
Makara Journal of Science
Published by Universitas Indonesia
ISSN : 23391995     EISSN : 23560851     DOI : https://doi.org/10.7454/mss.v26i2.xxx
Core Subject :
Makara Journal of Science publishes original research or theoretical papers, notes, and minireviews on new knowledge and research or research applications on current issues in basic sciences, namely: Material Sciences (including: physics, biology, and chemistry); Biochemistry, Genetics, and Molecular Biology (including: microbiology, physiology, ecology, taxonomy and evolution); and Biotechnology.
Arjuna Subject : -
Articles 4 Documents
 1 
Search results for , issue "Vol. 24, No. 1" : 4 Documents clear
Mixed-layer Heat Budget in Western and Eastern Tropical Pacific Ocean during El Niño Event in 2015/2016 Kusuma, Willy Anta; Nur, Muhammad; Khakim, Mokhamad Yusup Nur; Iskandar, Iskhaq
Makara Journal of Science Vol. 24, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Temporal variation of mixed-layer heat budget at two contrasting locations, namely, western Pacific (warm water pool) and eastern Pacific (cold tongue) during the extreme El Niño phenomenon in 2015/2016 is evaluated. Oceanic and atmospheric datasets, including sea surface temperature (SST), wind stress, shortwave radiation (SWR), longwave radiation, latent heat flux (LHF), and sensible heat flux are analyzed. A slight warming occurred in the eastern tropical Pacific associated with a positive SST anomaly, which reflected the weakening or reversal of the trade winds. Meanwhile, the western tropical Pacific exhibited a cooling tendency during the development phase of El Niño. Analysis of the mixed-layer heat budget shows that the net heat flux due to SWR and LHF significantly contributes to the warming of the eastern tropical Pacific. The contribution from horizontal advection was extremely small on both sides. The analysis shows that the residual term significantly contributes to cooling (warming) tendency observed in the western (eastern) tropical Pacific. This condition may suggest that residual process due to entrainment and diffusivity played an important role in the evolution of cooling (warming) process in the western (eastern) tropical Pacific.
Highly Sensitive Phenol Biosensor Utilizing Selected Bacillus Biofilm Through an Electrochemical Method Ariyanti, Dita; Iswantini, Dyah; Sugita, Purwantiningsih; Nurhidayat, Novik; Effendi, Hefni; Ghozali, Ali Aulia; Kurniawan, Yehezkiel Steven
Makara Journal of Science Vol. 24, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

An eco-friendly phenol biosensor from Bacillus biofilm was prepared and investigated. The biofilm, which produced tyrosinase enzyme, was successfully immobilized on a screen-printed carbon electrode surface. A total of 72 Bacillus isolates were utilized because of their capability to produce tyrosinase enzyme in tyrosine media. Among them, Bacillus isolate code 100 was selected because it produced an adequate amount of tyrosinase enzyme and a high potentiostat current. The response surface methodology was also used to optimize the phenol sensing condition through an electrochemical method. Results showed that the optimum condition was achieved after 6 days on a phosphate buffer solution (pH of 8), with an optical density of 0.33. Furthermore, the limits of detection and quantification were 3.0 and 13 ng/L, respectively. The measurements of precision yielded a relative standard deviation of < 5%, which is remarkable. Although the biosensor material was used for 35 days, the current throughout was still maintained at 90%, indicating that the evaluated biosensor material has the potential to be used for phenol monitoring on environmental samples in the near future.
Chemical Modification of Kola-Nut (Cola Nitida) Testa for Adsorption of Cu2+, Fe2+, Mg2+, Pb2, and Zn2+ from Aqueous Solution Slyvanus, Nwafor Ogechi; John, Chukwu Uche; Jnr, Horsfall Mike
Makara Journal of Science Vol. 24, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

In this study, kola-nut testa samples were modified with 0.1 M acetic acid and 0.1 M EDTA at room temperature. The modified Kola-nut testa samples were then characterized with respect to their pH at point of zero charge, melting point, specific gravity, Fourier-transform infrared (FTIR) spectra, and solubility. The characterization results of the modified Kola-nut testa (MKT) revealed that it was sparingly soluble in water, ethanol, and acetone but insoluble in n-hexane. The MKT had a specific gravity of 0.992 ± 0.020 and exhibited various pH values of 4.50 ± 0.50 and 12.00 ± 0.50 at the point of zero charges. The FTIR spectra of the MKT indicated the presence of –OH and –NH groups at 3310.97 cm−1, alkyl groups at 2928.53 cm−1, and aromatic rings at 1612.27–1529.81 cm−1. The results of the adsorption studies at various time intervals indicated that MKT had the capacity to adsorb Fe2+, Mg2+, Zn2+, Cu2+, and Pb2+ as follows: 1.90 ± 0.30 mg/g, 1.80 ± 0.20 mg/g, 1.40 ± 0.20 mg/g, 0.10 ± 0.01 mg/g, and 0.05 ± 0.01 mg/g, respectively. Thus, Fe2+, Mg2+, and Zn2+ were quantitatively removed from the aqueous solutions, whereas Cu2+ and Pb2+ were not. The adsorption of Fe2+, Mg2+, Zn2+, Cu2+, and Pb2+ by MKT from the aqueous medium was dependent on certain factors such as pH, temperature, adsorbent dosage, contact time, and initial metal-ion concentration.
Lactic Acid Bacteria from Apis dorsata Hive Possessed Probiotic and Angiotensin-Converting Enzyme Inhibitor Activity Meryandini, Anja; Karyawati, Amor Tresna; Nuraida, Lilis; Lestari, Yulin
Makara Journal of Science Vol. 24, No. 1
Publisher : UI Scholars Hub

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

One source of bacteria that has not been widely explored is lactic acid bacteria originating from honeycomb (hive). Timor Island has a wealth of giant honey bees (Apis dorsata). Lactic acid bacteria from the Apis dorsata hive in Timor Island need to be investigated to obtain probiotic candidates with specific functional properties. Lactic acid bacteria were isolated from honeycomb by using de Mann, Rogosa, and Sharpe agar supplemented with 1% of CaCO3. Bacterial isolates that formed clear zones and were Gram-positive and catalase-negative were determined as lactic acid bacteria. The probiotic candidates are isolates that are resistant to bile salts and low pH; susceptible to antibiotics; are able to aggregate, autoaggregate, and coaggregate; and have antibacterial activities. Isolate MC7 was selected as a probiotic candidate and had inhibitory activity against angiotensin-converting enzyme (ACE) with IC50 263,098 ppm. Isolate MC7 showed weak inhibition against ɑ-glucosidase activity. Molecular identification based on 16S rRNA gene showed that MC7 isolate was closely related to Lactobacillus rhamnosus with 100% similarity. Therefore, isolate MC7 was recommended as a probiotic candidate with a functional property as an inhibitor of ACE.

Page 1 of 1 | Total Record : 4

 1 

Filter by Year

2020 2020


Reset
Filter By Issues
All Issue Vol. 26, No. 2 Vol. 26, No. 1 Vol. 25, No. 4 Vol. 25, No. 3 Vol. 25, No. 2 Vol. 25, No. 1 Vol. 24, No. 4 Vol. 24, No. 2 Vol. 24, No. 1 Vol. 23, No. 4 Vol. 23, No. 3 Vol. 23, No. 2 Vol. 23, No. 1 Vol. 22, No. 4 Vol. 22, No. 3 Vol. 22, No. 2 Vol. 22, No. 1 Vol. 21, No. 4 Vol. 21, No. 3 Vol. 21, No. 2 Vol. 21, No. 1 Vol. 20, No. 4 Vol. 20, No. 3 Vol. 20, No. 2 Vol. 20, No. 1 Vol. 19, No. 4 Vol. 19, No. 3 Vol. 19, No. 2 Vol. 19, No. 1 More Issue