Indonesian Institute of Sciences
  • Jakarta, DKI Jakarta, Indonesia
Recent publications
Speleothem δ¹⁸O is widely used as a proxy for rainfall amount in the tropics on glacial-interglacial to interannual scales. However, uncertainties in the interpretation of this renowned proxy pose a vexing problem in tropical paleoclimatology. Here, we present paired multi-proxy geochemical measurements for stalagmites from southwest Sulawesi, Indonesia, and confirm changes in rainfall amount across ice age terminations. Collectively, the stalagmites span two glacial-interglacial transitions from ~380,000 to 330,000 and 230,000 to 170,000 years ago. Mg/Ca in the slow-growing stalagmites is affected by water moving through the karst and prior calcite precipitation, making it a good proxy for changes in local rainfall. When paired, Mg/Ca and δ¹⁸O corroborate prominent shifts from drier glacials to wetter interglacials in the core of the Australasian monsoon domain. These shifts in rainfall occur 4,000-7,000 years later than glacial-interglacial increases in global temperature and the associated response of Sulawesi vegetation, determined by speleothem δ¹³C.
Biofilm-associated infections are a critical element in infectious diseases and play an important role in antibiotic resistance. Biosynthesized gold nanoparticles (AuNPs) using ethanolic extract of Musa sapientum unripe fruit were performed. The nanoparticles demonstrated an absorption peak at 554 nm with particle sizes ranging from 5.45 to 104.44 nm. High negative zeta potential value of -33.97 mV confirmed the high stability of AuNPs. The presence of bioconstituents responsible for capping and stabilization was indicated by intensity changes of several peaks from Fourier-transform infrared spectroscopy analysis. The minimum inhibitory concentrations (MIC) of the biosynthesized AuNPs against important pathogens ranged from 10 to 40 μg mL-1 . Synthesized nanoparticles at 0.062 to 0.5 × MIC significantly inhibited biofilm formation in all the tested microorganisms (p < 0.05). Scanning electron microscopy and confocal scanning laser microscopy images clearly illustrated in disruption and architectural changes of microbial biofilms at sub-MIC of biosynthesized AuNPs. Excellent antioxidant and antityrosinase activities of AuNPs were observed. The biosynthesized AuNPs at 20 μg mL-1 significantly inhibited nitric oxide production by 93% in lipopolysaccharide-stimulated RAW 264.7 cells, compared with control (p < 0.05). The biosynthesized AuNPs at 0.6 to 40 μg mL-1 demonstrated no toxic effects on L929 fibroblast cells. This article is protected by copyright. All rights reserved.
Indonesia has a variety of traditional culinary delights from the results of mixing between tribes in Indonesia, as well as with immigrants such as the Chinese. Bogor is one of the cities in West Java Province, Indonesia which is famous for its various traditional culinary influences from Chinese immigrants. Traditional culinary is a variety of foods related to an area and passed through generations, one of which is the Bogor typical Gedong-Dalem pickles. However, nowadays the original Gedong-Dalem pickles are barely found, because it is hard to get the ingredients. This can influence its original taste. In addition, competition in the modern culinary business is highly competitive, so traditional culinary culture can be pushed aside until it is extinct. This study aims to show the ethnogastronomic data and uniqueness of the Gedong-Dalem pickles in Bogor area, Indonesia. Data collection was carried out through open-ended semi-structured and unstructured interviews with respondents and key informants using a questionnaire and observation. Based on the results of the interviews, the Gedong-Dalem pickle is a culinary made from a mixture of various species of fruits or vegetables which was originally sold in Gedong-Dalem by the Chinese in Bogor. The ethnogastronomy of Gedong-Dalem pickles is the key to harmony between Chinese and Indonesian mixed ancestry. Ethnogastronomically, it is a culinary origin from Indonesia, not entirely from China. In other words, it is an authentic Indonesian cuisine.
In this study, the catalytic activity of bifunctional SiO2/Zr catalysts prepared by template and chelate methods using potassium hydrogen phthalate (KHF) for crude palm oil (CPO) hydrocracking to biofuels was investigated. The parent catalyst was successfully prepared by the sol-gel method, followed by the impregnation of zirconium using ZrOCl2·8H2O as a precursor. The morphological, structural, and textural properties of the catalysts were examined using several techniques, including electron microscopy energy-dispersive X-ray with mapping, transmission electron microscopy, X-ray diffraction, particle size analyzer (PSA), N2 adsorption-desorption, Fourier transform infrared-pyridine, and total and surface acidity analysis using the gravimetric method. The results showed that the physicochemical properties of SiO2/Zr were affected by different preparation methods. The template method assisted by KHF (SiO2/Zr-KHF2 and SiO2-KHF catalysts) provides a porous structure and high catalyst acidity. The catalyst prepared by the chelate method assisted by KHF (SiO2/Zr-KHF1) exhibited excellent Zr dispersion toward the SiO2 surface. The modification remarkably enhanced the catalytic activity of the parent catalyst in the order SiO2/Zr-KHF2 > SiO2/Zr-KHF1 > SiO2/Zr > SiO2-KHF > SiO2, with sufficient CPO conversion. The modified catalysts also suppressed coke formation and resulted in a high liquid yield. The catalyst features of SiO2/Zr-KHF1 promoted high-selectivity biofuel toward biogasoline, whereas SiO2/Zr-KHF2 led to an increase in the selectivity toward biojet. Reusability studies showed that the prepared catalysts were adequately stable over three consecutive runs for CPO conversion. Overall, SiO2/Zr prepared by the template method assisted by KHF was chosen as the most prominent catalyst for CPO hydrocracking.
Bent-toed Geckos, genus Cyrtodactylus, are one of the most diverse terrestrial vertebrate groups, and their range extends from South Asia into Australo-Papua and adjacent Pacific islands. Given the generally high faunal endemism on Wallacean islands, it is rather paradoxical that the diversity in these geckos appears to be so low (21 species in Wallacea, 15 in the Philippines) compared with continental shelf assemblages (>300 species on Sunda + Sahul Shelves + adjacent islands). To determine whether this shortfall was real or an artifact of historical undersampling, we analyzed mitochondrial DNA sequences of hundreds of southern Wallacean samples (Lesser Sundas + southern Maluku). After screening to guide sample selection for target capture data collection, we obtained a 1150-locus genomic dataset (1,476,505 bp) for 119 samples of southern Wallacean and closely related lineages. The results suggest that species diversity of Cyrtodactylus in southern Wallacea is vastly underestimated, with phylogenomic and clustering analyses suggesting as many as 25 candidate species, in contrast to the 8 currently described. Gene exchange between adjacent candidate species is absent or minimal across the archipelago with only one case of >0.5 migrants per generation. Biogeographical analysis suggests that the hitherto unrecognized diversity is the result of at least three independent dispersals from Sulawesi or its offshore islands into southern Wallacea between 6-14 Ma, with one invasion producing small-bodied geckos and the other two or three producing larger-bodied geckos. The smaller-bodied laevigatus group appears to be able to coexist with members of either larger-bodied clade, but we have yet to find members of the two larger-bodied clades occurring in sympatry, suggesting that ecological partitioning or competitive exclusion may be shaping individual island assemblages.
We have synthesized ZnO nanostructure by using two-step methods i.e ultrasonic nebulizer and chemical bath deposition (CBD) at 95oC for two hours. The morphology, structural, reflectance, and photoluminescence properties have been characterized by the scanning electron microscope (SEM), the X-ray diffraction (XRD) measurement, ultraviolet-visible (UV-Vis) spectrophotometer, and photoluminescence spectrometer, respectively. Structurally, all samples possess polycrystalline hexagonal wurtzite structure, and the addition of Al-Cu decreases the crystallinity of ZnO nanostructures. Meanwhile, morphologically, the role of Cu dopants in Al-Cu co-doped ZnO nanostructures suppressed the growth of nanostructures in the c-axis. Hence, it can be used to modify the morphology of ZnO nanorods to nanodisks/nanosheets. Optically, the Al-Cu co-dopants can be used to shift the optical band gap energy of ZnO nanostructures to a lower wavelength (blueshift). The photoluminescence (PL) properties confirmed that the Al-Cu co-dopants have two peaks at the photon energy of 3.78 eV and 3.90 eV.
Surabaya is one of the big coastal cities in Indonesia with rapid municipal development. Thus, the investigation on the metal’s geochemical speciation in the coastal sediment is required to assess the environmental quality by studying their mobility, bioavailability, and toxicity. This study is aimed at evaluating the condition of the Surabaya coast by assessing copper and nickel fractionations and total concentrations of both metals in sediments. Environmental assessments were performed by using geo-accumulation index (Igeo), contamination factor (CF), and pollution load index (PLI) for existing total heavy metal data and by using individual contamination factor (ICF) and risk assessment code (RAC) for metal fractionations. Copper speciation was observed geochemically in the fraction order of residual (9.21 – 40.08 mg/kg) > reducible (2.33 – 11.98 mg/kg) > oxidizable (0.75 – 22.71 mg/kg) > exchangeable (0.40 – 2.06 mg/kg), while the detected fraction order of nickel was residual (5.16 – 13.88 mg/kg) > exchangeable (2.33 – 5.95 mg/kg) > reducible (1.42 – 4.74 mg/kg) > oxidizable (1.62 – 3.88 mg/kg). Different fraction levels were found for nickel speciation wherein its exchangeable fraction was higher than copper, even though the residual fraction was dominant for both copper and nickel. The total metal concentrations of copper and nickel were found in the range of 13.5 – 66.1 mg/kg dry weight and 12.7 – 24.7 mg/kg dry weight, respectively. Despite the fact that almost all index values are detected low through total metal assessment, the port area is indicated to be in the moderate contamination category for copper. Through the assessment of metal fractionation, copper is classified into the low contamination and low-risk category, while nickel is categorized into the moderate contamination level and medium risk to the aquatic environment. Although the coast of Surabaya generally remains in the safe category for living habitat, certain sites had relatively high metal concentrations estimated to have originated from anthropogenic activities.
Pseudomonas aeruginosa can regulate its pathogenicity via quorum sensing (QS) system. Zingiber cassumunar and Z. officinale have been used for the treatment of infectious diseases. The study aimed to evaluate and compare the chemical constituents, antibacterial, and QS inhibitor of Z. cassumunar essential oils (ZCEO) and Z. officinale essential oils (ZOEO). The chemical constituent was analysed using GC-MS. Broth microdilution and spectrophotometry analysis were used to evaluate their antibacterial and QS inhibitor activities. The main constituent of ZOEO with percent composition above 6% (α-curcumene, α-zingiberene, β-sesquiphellandrene, and β-bisabolene, α-citral, and α-farnesene) were exist in a very minimal percentage less than 0.7% in Z. cassumunar. All major components of ZCEO with percentages higher than 5% (terpinen-4-ol, sabinene, γ-terpinene) were present in low proportion (<1.18%) in Z. officinale. ZCEO demonstrated moderate antibacterial activity against P. aeruginosa. The combination of ZCEO and tetracycline showed a synergistic effect (FICI of 0.5). ZCEO exhibited strong activity in inhibiting biofilm formation. ZCEO at ½ MIC (62.5 μg/mL) was able to reduce pyoverdine, pyocyanin, and proteolytic activity. This is the first report on the activity of ZCEO in the inhibition of P. aeruginosa QS system and it may be used to control the pathogenicity of P. aeruginosa.
This study was undertaken to analyse the potential bioactivities including antibacterial, antioxidant and antidiabetic derived from the methanolic extract and the column chromatography ethyl acetate fraction (EtOAc Fr) of Horsfieldia spicata leaves. Methanolic extract and 4 other fractions was calculated for total phenol and flavonoid contents along with tested for antibacterial, antioxidant and antidiabetic. Interestingly, the EtOAc Fr had the highest value for total flavonoid content and the best antioxidant, and antidiabetic activities. Therefore, the EtOAc Fr was further separated using column chromatography technique. The results showed that the EtOAc column chromatography fractions namely F2, F3, F4 and F6 had the best clear inhibition antibacterial value against all bacterial tested. In addition, these fractions also exhibited better Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) values than others. Antioxidant, 2,2-diphenylpicrylhydrazyl (DPPH) assayed indicated that EtOAc Fr had the strongest IC50 value of 47.30 µg/mL. Further, F4 column chromatography fraction showed the best inhibition against α-Glucosidase enzyme related to antidiabetic activity with an IC50 value of 6.11 µg/mL. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) analysis identified that F4 derived from EtOAc fraction had several compounds belonging to the flavonoid and phenolics such as 3',5-Dihydroxy-7,4'-dimethoxy flavone, 5,7-Dihydroxy-3-(4'-hydroxybenzyl)-Chromone, and Kadsurenin I.
The Central Sumatra Basin is a vast sedimentary basin and has been proven to produce hydrocarbon; this basin consists of several different sub-basins that cannot be well-imaged with conventional seismic reflection section and limited well log data. This research aims to delineate sedimentary sub-basins, interpret the sub-surface geological model and identify geological structures beneath Eastern Central Sumatra Basin using integrated geophysical gravity, seismic and well data analysis. The sub-basins that can be delineated from the gravity data analysis are 13 sedimentary sub-basins, while the structural patterns identified are basement height, graben and fault. The 3D modeling results indicate that the Pre-Tertiary granitic basement is a continental crust with a mass density value of 2.67 gr/cc. Sedimentary rock from modeling results from the bottom to up, which is Early Oligocene-Middle Miocene sedimentary rock with a mass density value of 2.35 gr/cc. The results of the sub-surface geological modeling analysis show, based on the graben pattern and the basement high beneath the Eastern Central Sumatra Basin, many structural patterns support the development of petroleum systems similar to the western part of the basin that has already produced hydrocarbon. Our study also revealed the thickness of the Sihapas Formation, which is believed to have hydrocarbon reservoir potential.
Immobilized lipase has played an essential role in the chemical and biological sciences as a viable alternative to standard chemical catalysts. Glutaraldehyde is a low-cost crosslinking agent at risk of being superseded by developing crosslinking compounds with biocompatible, biodegradable, and non-toxic characteristics. The multipoint covalent treatment method using glutaraldehyde has both advantages and disadvantages. Immobilization techniques can be improved to improve the overall performance of immobilized lipase. The most recent update on lipase immobilization with multipoint covalent treatment by glutaraldehyde was summarized in this review. Covalent binding lipase on pre-activated support and aggregation-crosslinking lipase into crosslinked enzyme aggregates (CLEAs) or adsorption-crosslinking lipase on support are the most common immobilization techniques. Based on the above technologies, the advancement trends in important domains, such as the advancement of supports, additives, reactors, and cross-linking agents, are summarized. In addition, the application of the improved immobilized lipase by glutaraldehyde in the production of fatty acids, glycerides, biodiesel, and drug precursors was reviewed. In view of this, we put forward further studies on multipoint covalent treatment in lipase immobilization with glutaraldehyde. Various analytical methods are required to provide additional information about the structure of glutaraldehyde and its crosslinked products for assisting the proper immobilization conditions. Applying the composite strategy can also bring new opportunities for improving the efficiency of biological catalysts.
The relative influence of geography, currents, and environment on gene flow within sessile marine species remains an open question. Detecting subtle genetic differentiation at small scales is challenging in benthic populations due to large effective population sizes, general lack of resolution in genetic markers, and because barriers to dispersal often remain elusive. Marine lakes can circumvent confounding factors by providing discrete and replicated ecosystems. Using high-resolution double digest restriction-site-associated DNA sequencing (4826 Single Nucleotide Polymorphisms, SNPs), we genotyped populations of the sponge Suberites diversicolor (n = 125) to test the relative importance of spatial scales (1-1400 km), local environmental conditions, and permeability of seascape barriers in shaping population genomic structure. With the SNP dataset, we show strong intralineage population structure, even at scales <10 km (average F ST = 0.63), which was not detected previously using single markers. Most variation was explained by differentiation between populations (AMOVA: 48.8%) with signatures of population size declines and bottlenecks per lake. Although the populations were strongly structured, we did not detect significant effects of geographic distance, local environments, or degree of connection to the sea on population structure, suggesting mechanisms such as founder events with subsequent priority effects may be at play. We show that the inclusion of morphologically cryptic lineages that can be detected with the COI marker can reduce the obtained SNP set by around 90%. Future work on sponge genomics should confirm that only one lineage is included. Our results call for a reassessment of poorly dispersing benthic organisms that were previously assumed to be highly connected based on low-resolution markers.
3D printing is a rapidly developing technology in the medical world that has been used for pre-operative planning, prosthetic manufacturing, and training for medical education. This 3D printing is needed for medical education to make it easier for students to study anatomical structures. The advantages of 3D printing provide more detail and tactile representation of anatomical aspects of organs to address the problems of online learning and cadaveric limitations. This research aimed to develop the manufacture of 3D printed models of the human heart organ to improve understanding in learning for medical students. Making a 3D printed model of a heart organ is divisible into six parts: the aorta, right ventricle, left atrium, left ventricle, right atrium, and pulmonary artery. The 3D printing model creation procedure consisted of several steps: image acquisition, image post-processing, and 3D printing. This research used Computed Tomography Scanning (CT-Scan) images of the normal heart in Digital Imaging in Medicine (DICOM) format from Saiful Anwar Hospital, Malang. The segmentation uses the grow from seed technique with 3D Slicer software and is saved in STL format. The accuracy of the 3D printing was carried out by measuring dimensions and volume. Measurements are required to ensure the accuracy of 3D printing so that the resulting organs match the initial image data and can be used as learning media in anatomical structures by medical students.
We review morphology of Sunda Shelf Gonocephalus with an emphasis on Sumatran and Javan species. At least 15 species and subspecies inhabit Peninsular Malaysia, Sumatra, Java, Borneo, and adjacent smaller continental islands. Following analysis of external morphology, we provide a dichotomous key to Sunda Shelf Gonocephalus and resolve two taxonomic problems with this group of lizards. Three populations of Gonocephalus doriae on Borneo, Peninsular Malaysia, and Sumatra are recognized as subspecies, because they lack concordance of multiple morphological differences and have low genetic divergence in a 556 base-pair fragment of the 16S rRNA gene. Described as new herein, G. doriae brevis from Aceh and North Sumatra differs from G. d. abbotti and G. d. doriae in usually having more scales around midbody and a relatively shorter tail with fewer dark bands. Though previously reported as lost, a syntype of G. d. doriae (MSNG 29152) is designated as lectotype, illustrated, and described. Also described as new, G. inauris from high elevations of the Bukit Barisan Range of Bengkulu, Sumatra, is a species of the G. megalepis Group differing from all congeners in having 7/6 (vs. 8–19) loreals separating the last canthal and supralabials, 8/8 (11–27) infraorbitals, and 58 (73–153) scales around midbody. In this new species, distinctly enlarged suboculars broadly contact its supralabials, whereas 1–4 lorilabials separate the suboculars and supralabials in congeners. High genetic divergence in the new species mirrors its high level of morphological divergence.
Since its initiation, the Bali Botanic Garden (BBG) Seed Bank as an ex-situ conservation facility is conducted seed conservation and research programs. BBG Seed Bank also engages with education programs as a part and to support the botanic garden roles in biodiversity education. This study aims to review BBG Seed Bank participation in botanic education and discuss the challenges and opportunities that need to be addressed in the future. During this study available data regarding BBG Seed Bank education program is sourced and descriptively analyzed. Resulted data shows that BBG Seed Bank is already engaged in numerous botanic education programs both for the academic and general public. However, improvement to overcome challenges such as the lack of staff quality and quantity, the limited facilities, various backgrounds of participants is essential to improve the education program. Digital and social media platforms should be utilized more intensively by the seed bank to enable its educational program to reach a wider audience.
Radiation-induced graft polymerization using gamma rays was used in our previous study to synthesize a bacterial cellulose co-polyacrylamide adsorbent (BC-PAAM). In this work, the adsorption capacity of the adsorbent BC-PAAM towards copper and lead metal ions was investigated in a batch adsorption system under various parameters such as the contact time and the initial concentration of the metal ion. The pH of the metal solution was kept at 5 during the adsorption process. The equilibrium adsorption data is also interpreted from the Langmuir and Freundlich isotherms to find the most appropriate adsorption isotherm system. The results demonstrated that the Langmuir isotherm model was more applicable to describe the adsorption of the BC-PAAM adsorbent to Cu(II) and Pb(II) metal ions than the Freundlich isotherm model. The adsorption data fit well into the Langmuir isothermal model with a correlation coefficient, R²=0.9913 and R²=0.9713 for Cu(II) and Pb(II) adsorption onto BC-PAAM, respectively. While the correlation factor (R²) for Cu(II) and Pb(II) were 0.9755 and 0.922 for the Freundlich isotherm model. The RL value obtained was between zero and one, indicating that the adsorption of both Cu(II) and Pb(II) ions onto BC-PAAM is favorable.
Nickel nitride supported on natural bentonite was prepared and tested for hydrocracking Crude Palm Oil (CPO). The catalyst was prepared using the wet impregnation method and various nickel nitride loading. Subsequently, the nickel nitrate-bentonite was calcined and nitrided under H2 steam. The surface acidity of as-synthesized NiN-bentonite was evaluated using the gravimetric pyridine gas. Meanwhile, the physiochemical features of the catalyst were assessed using XRD, FT-IR and SEM-EDX. The results showed that the NiN species was finely dispersed without affecting the bentonite's structure. Furthermore, the coexistence of Ni and N species on EDX analysis suggested the NiN was successfully supported onto the bentonite, while the surface acidity features of raw bentonite were increased to 1.713 mmol pyridine/g at 8 mEq/g of nickel nitride loading. The catalytic activity towards the CPO hydrocracking demonstrated that the surface acidity features affect the CPO conversion, with the highest conversion achieved (84.21%) using NiN-bentonite 8 mEq/g loading. At all nickel nitride loading, the NiN-bentonite could generate up to 81.98-83.47% of bio-kerosene fraction, followed by the bio-gasoline ranging from 13.12-13.9%, and fuel oil ranging from 2.89-4.57%.
A natural fiber is potential material to use for wide range applications. Due to high content of cellulose, it is also abundant in nature. The combination of two fiber form sugarcane bagasse (SB) and rice husk (RH) could be used as template for magnetic nanoparticle biocomposites. In order to produce high functionality of biocomposites, it is important to modify by amine group. This research is focus on evaluate and characterized the concentration of amine precursor on synthesis of biocomposites. The delignified of both RH and SB were mixed in ethylene glycol, iron trichloride, sodium acetate anhydrous, and 1.6-hexanediamine. The solution was poured into Teflon Stainless Steel Autoclave then heated at 200 oC for 6 h. Amine source concentration was evaluated by different concentration of 1.6-hexanediamine. The 7 mL of 1.6-hexanediamine was achieved as optimum concentration with contain of 2.64 mmol/g. The Fe contain on biocomposites was 97.97% that proved by XRF analysis and has specific peaks at 36o, 43o, and 57o by X-Ray Diffraction (XRD). The peaks at 1640 cm⁻¹ and 582 cm⁻¹ are identified for N–H bending vibration and Fe-O on biocomposites, respectively. The iron content, amine group, and structure of of biocomposites could be good candidate for wide range applications.
Opportunistic observation of Erabu sea snakes (Laticauda semifaciata) provide evidence that these species undertake a novel foraging tactic; coordinated communal hunting. Erabu sea snakes prey on cryptic fish species in highly complex reef habitats. Intra- and interspecific cooperative hunting strategies may increase chances for all members of the hunting party to encounter and capture prey in these complex habitats. Here we recorded 52 instances of communal hunting by Erabu sea snakes with conspecifics and other predatory fishes at recreational dive sites in Southern Lombok, Indonesia. These observations highlight the potential higher cognitive capacity of sea snakes to coordinate activities around communal hunting events.
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1,280 members
Yusuf Nur Wijayanto
  • Research Center for Electronics and Telecommunication
Paskah Partogi Agung
  • Laboratory of Reproduction, Breeding, and Animal Cell Culture
Muryanto -
  • Division of Environmental Technology
Crescentiana Dewi
  • Technical Management Unit for Chemical Process and Technology Development
Iman Hidayat
  • Research Center for Biomaterial
Jl.Gatot Subroto no.10, 12710, Jakarta, DKI Jakarta, Indonesia
Head of institution
Dr. Laksana Tri Handoko