bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Carbazole Compounds Endowed with Phosphonic Anchoring Group for Sensitizer in Dye-Sensitized Solar Cells
Authors: Kusumawati Y , Pamungkas B S 
Published: July 2020

Abstract
The sensitizer dye contacts onto the TiO2 surface through an anchoring group in a Dye-Sensitized Solar Cells (DSSC). The thermal stability of the anchoring group and TiO2 binding contact is important to be considered in order to obtain the cell stability. Phosphonic acid is an anchoring group that has a good binding-contact thermal stability with TiO2 surface. In this research we investigated through the computational study the electronic properties of carbazole derivative compounds endowed with the phosphonic anchoring-groups (CP). A series of 10 CP derivatives was studied which has a different functional donor group. The electronic properties were investigated using the TD-DFT method with the CAM-B3LYP basis set. The substitution of carboxyl group with the phosphonic one showed the absorption spectrum to the blue shift (5-70 nm) which gave a less beneficial effect to the DSSC performance. The addition of donor functional group aniline into the CP (aniline-CP) could shift back the absorption spectrum to the red-shift. The DSSC parameter also has been calculated including the electron injection driving force ΔGinject and the open circuit votage (eVOC). Overall the aniline-CP has the best performance among the observed compounds which showed the highest ΔGinject (-0.84872 eV) and eVOC (2.763 V).
A Potency of Microcellulose from Pineapple Leave Isolated by Hydrolysis-Assisted Sonication
Authors: Latif Luqi Khoiriyah , Masruri Masruri , Rumhayati Barlah 
Published: July 2020

Abstract
Cellulose has been reported have many functions for separation and adsorption of heavy metals and organic materials waste or pollutants. This paper reported the preparation of micro size cellulose from the waste of pineapple leaves. The strategy involves delignification, bleaching, and hydrolysis process. The hydrolysis step plays an important role for cutting of the cellulose chain, and ultrasonication assisted hydrolytic procedure was applied. In addition, the isolated product was characterized by means of FTIR spectrometry to identify functional group, Scanning Electron Microscopy to inform morphology features, and Particle Size Analyzer to inform the size of cellulose particle. The yield of initial isolated cellulose was 62.07%. Then, through the ultrasonication process using 30% of sulphuric acid for 1 hour at room temperature resulted about 3.497% yield of microcellulose. The FTIR show O-H, C-O-specific band for cellulose in 3402 cm−1, 1385 and 1200-1300 cm−1, respectively. This finding lead for further application of this micro/nano-cellulose for heavy-metals-and dye pollutants adsorbent.
Emulsifier and antimicrobial activity against Propionibacterium acnes and Staphylococcus epidermidis of oxidized fatty acid esters from hydrolyzed castor oil
Authors: Nabilah A , Handayani S , Setiasih S , Rahayu D U C , Hudiyono S 
Published: July 2020

Abstract
This study aimed to synthesize esters from oxidized fatty acids produced by castor oil hydrolysis as emulsifiers and antimicrobial compounds. Castor oil was hydrolyzed using KOH and the fatty acids were then oxidized using KMnO4. The success of oxidation proven by determined the iodine number. Esterification was conducted with varied alcohols, namely methanol, ethanol, isopropanol, and 1-butanol using ZnCl2 as catalyst and mole ratio was 1:2. The conversion percentage of esterification was determined using titrimetric method and products were characterized using FTIR. From the hydrolysis of castor oil, 84% of fatty acids were produced. Decreasing iodine number from 43.38 mg/g to 13.11 mg/g and increasing intensity of the -OH group absorption in the FTIR spectrum showed the success of fatty acids oxidation. Emulsifier test showed all products have emulsifier ability and emulsions were stable up to 24 hours with a water-in-oil (w/o) emulsion type. The best ability as an emulsifier demonstrated by methyl ester. Antimicrobial assay against Propionibacterium acnes and Staphylococcus epidermidis showed all ester products could inhibit the growth of both bacteria. Largest inhibition zone obtained from isopropyl ester for P. acnes by 16 mm and butyl ester for S. epidermidis by 17 mm.
Electron transfer study between hydrogen molecules and graphene surface
Authors: Nasri  , Subagyono R R D J N , Gunawan R 
Published: July 2020

Abstract
Electron transfer studies on the interaction of graphene surface and hydrogen (H2) molecules have been carried out. The calculations were based on the Density Functional Theory (DFT) with a basis set of Generalized-Gradient-Corrected PBE method approach (Perdew-Burke-Ernzerhof). The results showed that the optimum distance (lowest potential energy) between hydrogen molecules on the surface of the graphene was 3.2 Å, and the partial density of state (PDOS) calculation showed that the hydrogen-graphene system band gap was 2.51 eV. The electron transfer shown by the isosurface value indicates that the electron transfer from the p sub orbitals from the surface of the graphene to the hydrogen molecular orbitals was +0.3603 e/Å.
Acetylacetone as A Potential Chemosensor for Rapid Detection of Cu(II) in Aqueous Media
Authors: Nugroho Antonius Agung , Kurniawan Yehezkiel Steven , Yuliati Leny 
Published: July 2020

Abstract
Monitoring of Cu(II) ions is one of the most critical issues in wastewater treatment. Since the application of diketone-derived compounds as the Cu(II) chemosensor has not been addressed yet, in this present work, acetylacetone (penta-2,4-dione) was employed as the chemosensor to detect Cu(II) ions in the aqueous media. Ultraviolet (UV)-visible spectra showed that the blue colored-Cu(II) solution gave absorption at 811 nm, while the acetylacetone only gave absorption at UV region of 272 nm. Interestingly, the blue Cu(II) solution immediately turned to green solution after the addition of Cu(II) solution into the ligand solution, giving a new peak at 748 nm due to formation of Cu(II)-acetylacetone complex. This large blue shifting suggested the potential application of the acetylacetone as a colorimetric sensor of Cu(II), which gives benefit in the rapid detection. The limit of detection (LoD) and limit of quantification (LoQ) were found to be 0.15 and 0.51 mM, respectively. Furthermore, the presence of other metal ions, such as Na(I), K(I), Mg(II), Mn(II), Ni(II), Al(III), Au(III) and La(III), could be neglected since they gave low extents of interferences up to less than 10%. These results demonstrated that the acetylacetone is a potential chemosensor for Cu(II) detection in the aquatic environment.
Oxalic Acid from Corn Stalk for Photocatalytic Reduction of Cr(VI)
Authors: Nurjanah Ana , Rumhayati Barlah , Wiryawan Adam 
Published: July 2020

AbstractCr(VI) is toxic species of chromium in the aquatic environment. The reduced species, Cr (III), has lower toxicity than Cr(VI). The change of Cr(VI) species to Cr(III) can be conducted by photocatalytic reduction using oxalic acid as an oxidant with the aid of Fe(III) as a catalyst. Oxalic acid can be isolated from the biomass waste of corn stalk. This research aimed to isolate oxalic acid from corn stalk biomass as an oxidator for Cr(VI) photocatalytic reduction. The oxalic acid was isolated from corn stalks powder using NaOH, precipitated with the addition of CaCl2, acidified with H2SO4, and then crystalized to form the oxalic acid crystals. The photocatalytic reduction was carried out in a closed reactor equipped with two of 30-watt UV lights. About 30 mg of oxalic acid was used to reduce 300 mg/L Cr(VI) with the presence of 4 ml Fe(III) 100 mg/L as a catalyst. The process was conducted for 120 minutes while stirring. The reduction efficiency was calculated from the differentiation of the initial Cr(VI) concentration to the final ones. Cr(VI) concentrations were measured as Cr(VI)-diphenylcarbazide complex compound at pH 2 that could be detected at 540 nm. The results showed that the isolated oxalic acid has hydroxyl and carbonyl groups at 3441 cm−1and 1627 cm−1respectively identical with the oxalic acid standard. The crystals have melting point at 103°C. It could be used effectively to reduced Cr(VI) up to 45.9 %.
Mechanical Properties of Alginate Based Biopolymers as Wound Dressing Material
Authors: Nurjanah Ane , Amran Muhammad Bachri , Rusnadi  
Published: July 2020

Abstract
The utilization of biopolymers has been widely accepted in many areas due to its eco-friendly. Especially in medical care, biopolymers are receiving great attention and are considered as a potential for wound healing. Wound dressing material is one of medical needs and the demand continue to raise. One of the most widely used biopolymers for wound dressing is alginate. To improve alginate properties as wound dressing material, various alginate modifications with nanoparticles or synthetic polymers have been developed. In this paper alginate biopolymer will be modified with ZnO nanoparticles and synthetic polymer, such as poly (ethylene glycol) dimethacrylate (PEGDMA) as one of the candidates of wound dressing material. Alginate can go through swelling and because of its crystallinity is low so that it affects its mechanical properties. In order to increase the compatibility, ZnO needs to be modified with PEGDMA which is crosslink with alginate to strengthen the bonding network of materials. Characterization of alginate-based wound dressing material was performed using FTIR, XRD and SEM. In addition, optimization tests of mechanical and antibacterial resistance properties were performed to meet detailed studies of the effect of ZnO nanoparticles and PEGDMA interpenetrated into alginate to the properties of the wound dressing material.
Antifungal Activity from Co-Culture of a Local Fungus of Tropical Peat Swamp Soil, Penicillium sp. LBKURCC34 with Gram-Negative and Gram-Positive Bacteria
Authors: Nurulita Yuana , Yuharmen  , Dahliati Andy , Eryanti Yum , Supridianto  , Khairulinas  , Haryani Yuli , Nugroho Titania Tjandrawati 
Published: July 2020

Abstract
Microorganism is important producer of novel bioactive natural products, particularly in the field of drug discovery. Co-culture methods is one of powerful emerging tools for enhancing the chemical diversity of microorganisms. This research used the local culture collection of Penicillium sp. LBKURCC34, the fungus isolated from peat soil of primary forest at Giam Siak Kecil Bukit Batu (GSKBB) - Biosphere Reserve in Riau Province, to produce secondary metabolites secreted to their growth media that was cultivated by two different Gram of bacterial pathogen, Escherichia coli and Staphylococcus aureus. The 14 days fermentation was carried out and the media was extracted with ethyl acetate. The ethyl acetate crude extract was evaporated, then the concentrate dissolved in methanol. Antifungal, Candida albicans test was performed by the disc diffusion and the resazurin-based turbidimetric method. This study found that the crude extract of the co-culture with S. aureus could inhibit C. albicans growth, while that extract of the co-culture with E.coli could not do. The value of minimum inhibitory concentration (MIC) of the potential extract was less than the positive control, Ketoconazole. It only has potency as bacteriostatic extract.
Consistency of Spectra and Antibacterial Activity of The Extract Mixture of Curcuma longa, Zingiber officinale, and Syzigium aromaticum
Authors: Pangesti Dwika Putri , Masruri Masruri 
Published: July 2020

Abstract
Finding new antibiotic based on local resources is always a challenging effort, since Indonesia almost totally import the antibiotics. Then, antibiotic based jamu is an alternative. Jamu is a traditional herb prepared from local plants and some rhizomes, such as Curcuma longa, Zingiber officinale, and Syzigium aromaticum. These plants have been reported for their antibacterial capability. This paper is focused on the evaluation of antibacterial of these mixtures and their spectral consistency. The method was initiated by extraction of each plants/rhizome using ethanol and water. Each extract was mixed with equal ratio, and further evaluation for growth inhibiting activity in Staphylococcus aureus and Escherichia coli. Meanwhile, the spectral analysis was determined using FTIR and UV-Vis spectrophotometry. The result showed that the mixture of ethanol extract gives a slightly better activity than that using water extract. Furthermore, the UV-Vis spectra of the mixture from ethanol extracts indicates different band absorption in 439 and 417 nm, but no absorption observed in water extract in this range. In addition, the ethanol mixture extract also gives new band (FTIR spectra) in between 1010-1045 cm−1, that these are not observed in water extract. In short, it can be summarized that ethanol extraction process give better extraction procedure and provide better antibacterial activity.
Carbon dioxide occupancies inside ice XVII structure from grand-canonical Monte Carlo simulation
Authors: Pradana Irwansyah Putra , Mardiana Diah , Hakim Lukman 
Published: July 2020

Abstract
Clathrate hydrate is a promising material that can be used to trap the carbon dioxide (CO2) as a mean for the greenhouse-gas emission control. A compromise between experimental findings and density functional theory calculations was recently made to determine the occupancy of the newly reported CO2 clathrate hydrate of ice XVII structure. In this work, a hybrid isobaric Grand-Canonical Monte Carlo simulation is performed as a direct approach to determine CO2 occupancy inside ice XVII structure. The simulation results show that the CO2-to-water ratio starts at about 1:3.55 under lower pressure and ends at about 1:4 under high pressure. The potential energy of CO2-water interaction as a function of CO2 molecule displacement inside the voids shows a cage-like character, and the orientation of CO2 molecules inside the spiral void is shown to be well-ordered. The simulation results support the experimental observation and provide molecular insight into the structure of CO2 molecules inside the ice XVII structure.
Toxicity and Radical Scavenger Properties of Various Extracts of Sponge Clionidae sp. Kangean Islands
Authors: Rahman Moh. Farid , Masruri Masruri , Dibha Alyaa Farrah 
Published: July 2020

Abstract
Sponge Clionidae sp. is a multicellular animal that has active secondary metabolites that are used for survival. Sponge has cytotoxic, anticancer and antitumor properties and can be used in the pharmaceutical field, but the toxicity and antioxidant levels must be done to determine the uses level. Toxicity levels of sponge Clionidae sp. against Artemia salina L. and the IC50 value of the antioxidant was tested against DPPH radicals. Extraction of sponge Clionidae sp. was carried out with sonication using methanol, n-butanol, ethyl acetate and n-hexane as solvents. Then, the crude extract was tested for toxicity levels by the BSLT method and the antioxidant test by the DPPH method. Sponge extracts with ethyl acetate has the highest LC50 at 62.50 ppm and n-butanol has the highest IC50 values of 77.34 ppm. Identification of extract sponge with ethyl acetate was carried out using a UV-Vis spectrophotometer, resulting a maximum wavelength at 407.5 nm, ethyl acetate sponge extract showed the presence of O-H stretch groups 3327 cm−1, C-H stretch 2922 cm−1, C=C aromatic 1462 cm−1, and C=O 1711 cm−1 by FT-IR. The dominant compound in ethyl acetate extract that identified in LC-HRMS are chlorhexidine, 1,3,7-octanetriol, tobramycin, stigmatellin Y and maraniol.
Evaluation of The Stability and In Vitro Anti-inflammatory Activity of Partially Purified Bromelain Nanoemulsion
Authors: Randy Fransiskus , Setiasih Siswati , Jufri Mahdi , Handayani Sri , Hudiyono Sumi 
Published: July 2020

Abstract
Bromelain is an enzyme belonging to cysteine protease. It is known for topical use as debridement for inflammation treatment. Nanoemulsion of bromelain (NEB) aims to solve this problem and also improve its stability. NEB was made by high emulsification method using homogenizer and sonicator. Nanoemulsion physicochemical stabilities were evaluated. The bromelain as an active compound was isolated from the core of pineapple (Ananas comosus [L.] Merr) which was purified by ammonium sulphate fractionation and then dialysis followed. Nanoemulsion formula 2 was found to be the most suitable formula for encapsulating bromelain with good physicochemical stability after 30 days of storage. This formula showed clear visual appearance with globule diameter of 37.42 nm with polydispersity index of 0.40. The result showed that the fraction of bromelain obtained from each purification step showed an increase in specific activity. The specific activities of fractionation using 20-50% ammonium sulphate and dialysis were 152.05 and 266.58 U/mg, respectively. The purest bromelain fraction was encapsulated into nanoemulsion formula 2. The bromelain fraction’s anti-inflammatory activity was tested based on HRBC membrane stabilization method. The result showed that bromelain dialysis fraction shows the ability as anti-inflammatory agent with stability percentage of 79.76%.
The Potency of Plant Dye Extracts for Halal Detection on Consumed Animal Fats
Authors: Retnowati Rurini , Sulistyarti Hermin , Suratmo  
Published: July 2020

Abstract
One point of the halal concepts is the food does not contain any lard or any pigs derivatives. UV-vis spectrophotometry using natural dyes, among other methods, can be developed for animal fat analysis. One factor that influence the analysis is the solubility of animal fats and natural dyes in organic solvents. This research was conducted to study the differences of UV-vis spectrum profile in animal fats (chicken, beef, lamb, pork) using various natural dyes (namely Curcuma longa Linn., Curcuma zanthorriza, Curcuma heyneana, Zingiber montanum, Uncaria, Caesalpinia sappan, and Areca catechu) in different type of solvents. The research consists of four main steps: 1) screening of plant dyes in several solvents with different polarity, 2) screening of animal fat in several solvents with different polarity, 3) screening of animal fats mixed with plant dyes in selected solvents, and 4) analysis of animal fats mixed with plant dyes in selected solvents by UV-Vis spectrophotometry. The results showed that plant dyes from C. longa Linn., C. zanthorrhiza, A. catechu, and Uncaria, well as all animal fats used in this work, were soluble in ethyl-acetate and isopropanol. UV-vis spectrum profile of the animal fats with turmeric dyes in ethyl-acetate for chicken, beef, pork, and lamb fats, shows peaks at λ of 484, 792, 488.5, and 741 nm with absorbance of 3.913, 0.816, 3.524, and 0.175 respectively. Meanwhile in isopropanol, the profile for chicken, beef, pork, and lamb fats have λ of 751, 787, 712, 499 nm with absorbance of 0.007, 1.012, 0.479, and 3.913, respectively. Therefore, the UV-vis spectrum profile of animal fat with C. longa Linn dyes in ethyl-acetate can distinguish lard from the beef and lamb fats. In isopropanol, the lard cannot be distinguished from the chicken and beef fats, but it can differentiate lard from the lamb fats. The C. zanthorrhiza dyes in ethyl-acetate cannot distinguish lard from the chicken, beef, and lamb fats, but C. zanthorrhiza dyes can distinguish lard from the beef fat using isopropanol as the solvent. For A. catechu and Uncaria dyes in ethyl-acetate and isopropanol, they all cannot distinguish lard from the chicken, beef and lamb fats.
Sulphate Removal from Wastewater in Constructed Wetland Ecotechnology Using Pumice Amended in the Sand Media
Authors: Rozari Philiphi de , Dua Monang Maria Agusta , Krisnayanti Denik Sri , Tawa Bibiana Dho 
Published: July 2020

AbstractSulphate is a part of sulphur compounds which potentially inhibit plant growth and microbial activities in receiving surface water. Thus, it is important to remove concentration of sulphate from wastewater to acceptable concentration before the water is released into aquatic system. Constructed wetlands (CWs) are good option of wastewater treatments due to their low-cost and eco-technology. This research aimed to investigate the removal of sulphate from domestic wastewater using sand media amendment with pumice in CWs. In this experiment, six variations of CWs consisting sand and pumice planted with lemongrass (Cymbopogon citratus) were established. Domestic wastewater was loaded into CWs with loading rate 2 L/day. Sulphate concentrations were determined in inflows and outflows. The results showed that all treatment significantly remove sulphate concentrations from the inflow. The highest removal efficiency was in the media with 100% of pumice.
Analysis of Fe in Coral Reefs for Monitoring Environmental Areas of Prigi Coast Waters Using the Tessier-Microwave Method
Authors: Suci Cahyanti Wulan , Wijaya Anugrah Ricky 
Published: July 2020

Abstract
This study revealed the analysis of Fe content in the coral reef of Prigi Coast to monitor its waters as an environmental biomonitoring agent. Fe can accumulate into the coral structure through food, the mucous tissue, the mesenterium filament, and calcium element substitution that built-in the each of Fe coral fractions. Fe can be leached in the coral reef fractions using the Tessier-microwave method. Tessier microwave method divided of Fe in the ion exchange (fraction 1), carbonate bound (fraction 2), reduction (fraction 3), oxidation (fraction 4) and residual (fraction 5), respectively. The Tessier-microwave method results detected of Fe in the fraction 3 only, indicated that all of the Fe in the coral reefs was bound to the reduction fraction. The Fe content in the fraction 3 at 6 selected locations of Prigi Coast was 127.10 ppm, 39.12 ppm, 56.64 ppm, 78.10 ppm, 11.46 ppm, and 47.62 ppm, respectively. According to several calculations of CF, PLI and Igeo indexes, it indicated the contaminated of Fe in the coral reefs, especially at reduction fraction.
Development of Indirect Spectrophotometric Method for Mercury Determination Based on The Formation of Iron(III)-Thiocyanate Complex
Authors: Sulistyarti Hermin , Retnowati Rurini , Sulistyo Erwin , Wulandari Eka Ratri , Nashukha Hikmanita Lisan 
Published: July 2020

Abstract
A new spectrophotometric method for mercury determination has been developed based on the complexation of mercury(II) in ascertained excess of thiocyanate. The remaining thiocyanate is reacted with iron(III) to form a red iron(III)-thiocyanate complex which gave maximum absorbance at 460 nm. The concentration of mercury(II) is inversely proportional to the decrease absorbance of the complex. The method was optimized to the concentrations of thiocyanate and iron(III). Selectivity of the method has also studied based on percent recovery of mercury(II) in the presence of common metal ions in the tailing waters of gold mine. Under the optimum conditions, the method showed linear correlation to mercury(II) concentration from 1-30 mg L−1 with detection limit of 0.58 mg L−1. The method was not interfered in the presence of all metal ions studied up to 50 mg L−1, except of silver which was tolerated at 10 mg L−1. The developed method has been satisfactorily applied for mercury(II) determination in synthetic and tailing waters of gold mine samples.