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Science and Technology Indonesia
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This is an Open Access Journal

Open Access journal
ISSN (Print) 2580-4405 - ISSN (Online) 2580-4391
Published by Sriwijaya University

[4 journals]

Study on Volatile Compounds of Gelatine and The Maillard Reaction Products
from Different Species Using SPME-GCMS
- Authors: Ismarti Ismarti, Dody Dwi Handoko, Kuwat Triyana, Hamzah M. Salleh, Nurrulhidayah A. Fadzillah, Noor Faizul Hadry Nordin
  Pages: 132 - 139
  Abstract: Food fraud and adulteration are the global issues, currently. One important issue is about gelatine since it comes from many sources of animals. Therefore, analytical method for gelatine must be developed and used for the authentication. This study was conducted to investigate the Volatile Compounds (VCs) of gelatine and the Maillard Reaction Products (MRPs) which are responsible to their aroma. Three gelatine standards from bovine, fish and porcine bought from Sigma Aldrich were used. A high reactivity reducing sugar namely xylose was used in the Maillard Reaction (MR). A Solid Phase Micro Extraction-Gas Chromatography-Mass Spectroscopy (SPME-GC-MS) used to evaluate the VCs in the samples. The VCs were identified by comparing the mass spectra of the compounds with database of NIST library. Moreover, retention time using the n-Alkane index were compared with literature data. There were 67 VCs have been identified. Among them, furfural, acetic acid, nonanone, dimethyl disulphide and decanone were considered as the important volatiles in gelatine due to its abundance. In the MRPs, furfural, 1-(2-furanylmethyl)-1H-pyrrole, 1-(2-furanyl)- ethanone, acetic acid and 2,2’-bifuran were predominant. Additionally, heptanol, octanal, nonanal, nonanone, dimethyl disulphide and dimethyl trisulphide could be considered as the important compounds due to its low odour threshold value. The compounds had a direct influence on the overall aroma of samples and could be potential to use in gelatine differentiation.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.132-139
  Issue No: Vol. 7, No. 2 (2022)
Influence of Sepiolite Addition Methods and Contents on Physical
Properties of Natural Rubber Composites
- Authors: Nabil Hayeemasae, Ajaman Adair, Mohamad Syahmie Mohamad Rasidi, Patiwarada Jitsopin, Abdulhakim Masa
  Pages: 140 - 148
  Abstract: The influence of sepiolite loadings (1-10 phr) and sepiolite addition procedures (mill and latex mixing approaches) on properties improvement of natural rubber composites was investigated. The viscosity, curing behavior, and tensile test were used to assess the property changes whereas the rubber-filler interactions was confirmed by using stress relaxation, swelling, Mooney-Rivlin and rheological methods. It was found that the characteristics of rubber composites influenced by both mixing methods and filler contents. Comparing between two different mixing methods, the slower stress relaxation rate and less swelling capability were achieved from mill mixing technique. This method also lowered the strain where the upturn of stress was occurred as suggested by Mooney-Rivlin plot. The greater properties enhancement of composites was obtained from milling method because of the better rubber-filler interactions, probably as a result of the nature of filler used. The greatest tensile strength improvement was achieved at 1 phr sepiolite loading where the smallest damping characteristics (tan '''') indicating the highest elastic behavior were obtained as revealed by rheological measurements. The simplicity of production and shortened step of milling procedure would be more favorable than the latex mixing approach for fabrication sepiolite filled rubber composites.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.140-148
  Issue No: Vol. 7, No. 2 (2022)
Optimization of Antibacterial Production of Endophytic Fungi with Various
Sources of C, N, and pH using The Response Surface Methodology
- Authors: Hary Widjajanti, Elisa Nurnawati, Muharni, Eca Desriana Zahwa
  Pages: 149 - 157
  Abstract: Secondary metabolites extract of McB1 endophytic fungi from gelam (Melaleuca cajuputi Powell.) leaves have a high potential antibacterial activity against Escherichia coli ATCC8739 and Staphylococcus aureus ATCC6538 with flavonoids and phenol as bioactive compound. The low production of secondary metabolites extract in the cultivation stage and the high potential antibacterial activity of bioactive compounds produced by McB1 endophytic fungi require special treatment for optimize the secondary metabolites product. This is possibly achieved by optimizing the composition of the cultivation media, where various sources of carbon, nitrogen, and pH produce different amounts and classes of secondary metabolites. The objectives of the research to obtain the optimum interaction between sources of carbon, nitrogen, and pH for the production of secondary metabolite extract using Response Surface Methodology (RSM). The results showed that the highest extract (0.25 g) with the composition of sucrose as carbon source, yeast extract as nitrogen source, and pH 6. Based on the optimization of the medium with a variation of 4.5 gL-1 sucrose, 0.48 gL-1 yeast extract, and pH 6.1 yielded 0.34 g of secondary metabolites extract of McB1 endophytic fungi. The chromatogram profile of the optimized secondary metabolite extract showed the presence of flavonoids, phenols, terpenoids, and tannins.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.149-157
  Issue No: Vol. 7, No. 2 (2022)
The Synthesis of CuO/Polystyrene Nanocomposite Superhydrophobic Layer
using The Spin Coating Method
- Authors: Ratnawulan Ratnawulan, Ahmad Fauzi, Sarimai Sarimai
  Pages: 158 - 163
  Abstract: This paper shows the synthesis of CuO/Polystyrene(PS) nanocomposite superhydrophobic layer using the spin coating method. The objective of this study was to determine the effect of calcination temperature on the contact angle, morphology, and energy gap of the CuO/PS nanocomposite thin layer. Preparation of copper powder into copper oxide (CuO) nanoparticles using the method of High Energy 3 Dimensional Milling (HEM-3D) for 20 hours. The calcination temperature variations used were 100◦C , 150◦C, 180◦C, 200◦C, and 300◦C. In this study, sample analysis was performed using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Ultraviolet-Visible (UV-Vis) Spectrophotometry. The contact angle was determined using the sessile drop method. The findings indicate that the calcination temperature affects the contact angle of the nanocomposite thin films the highest contact angle was obtained at 162◦ at a temperature of 200◦C. The results of SEM analysis obtained that at a temperature of 200◦C, the particle size was 62.91 nm and the particles were evenly distributed in the composite layer. The energy gap at 200◦C is 2.03 eV. We found that CuO/PS synthesized at a temperature of 200◦C was superhydrophobic.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.158-163
  Issue No: Vol. 7, No. 2 (2022)
The Comparison of WLS and DWLS Estimation Methods in SEM to Construct
Health Behavior Model
- Authors: Ferra Yanuar, Fadilla Nisa Uttaqi, Aidinil Zetra, Izzati Rahmi, Dodi Devianto
  Pages: 164 - 169
  Abstract: It is unknown how reliable various point estimates, standard errors, and standard several test statistics are for standardized SEM parameters when categorical data used or misspecified models are present. This paper discusses the comparison between WLS and DWLS for examining hypothesized relations among ordinal variables. In SEM, the polychoric correlation is employed either in WLS or DWLS. This study constructs the Health behavior model as an endogenous latent variable in which exogenous latent variables are Perceived susceptibility and Health motivation. All indicators are in categorical types. Thus, data are not multivariate normal, or the model could be misspecified. This study compares the values of standard deviation and coefficient determination to determine a better model. The criteria for the goodness of fit for the overall model are based on RMSEA, CFI, and TLI values. This present study found that the WLS estimator method resulted in better values than DWLS’s.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.164-169
  Issue No: Vol. 7, No. 2 (2022)
Mg/Al-chitosan as a Selective Adsorbent in The Removal of Methylene Blue
from Aqueous Solutions
- Authors: Patimah Mega Syah Bahar Nur Siregar, Aldes Lesbani, Risfidian Mohadi
  Pages: 170 - 178
  Abstract: The use of dyes in the textile industry is detrimental to aquatic biota and humans. Pollution caused by dye waste can be overcome by adsorption methods using adsorbents such as LDH. LDH is known as an adsorbent that is often found in the process of removing dye waste, but repeated use is not effective. This can be overcome by the LDH modification process using a supporting material such as chitosan. Modification of LDH can be done using coprecipitation or precipitation simultaneously at pH 10. XRD analysis where the peaks that appear in Mg/Al-chitosan are similar to the typical peaks of the constituent materials, namely Mg/Al and chitosan. This is confirmed by FTIR analysis where the spectrum that appears in Mg/Al-chitosan is similar to the spectrum in Mg/Al and chitosan. As well as BET analysis where there is an increase in the surface area of Mg/Al after being modified to Mg/Al-chitosan from 5.845 m2/g to 24.556 m2/g. In this study, the selectivity process for the dye mixture was carried out first with the most selective dye for the Mg/Al-chitosan adsorbent was methylene blue. Methylene blue was continued for adsorption processes such as isotherm adsorption kinetics and adsorption thermodynamics as well as adsorbent regeneration studies. The results showed that at 90 minutes the adsorption reached equilibrium. The adsorption capacity of Mg/Al increased after modification using chitosan from 84.746 mg/g to 108.696 mg/g. The adsorption process follows the Langmuir isotherm type where adsorption occurs chemically (monolayer). Regeneration studies show that Mg/Al-chitosan is an adsorbent that can be used repeatedly with stable adsorption effectiveness until the fifth cycle.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.170-178
  Issue No: Vol. 7, No. 2 (2022)
Chaos Theory of 0-1 Test and Logistic Map in New Confirmed COVID-19 Cases
- Authors: Norliza Muhamad Yusof, Muhamad Luqman Sapini, Lidiya Irdeena Az’hari, Nor Akma Hanis Roslee, Siti Noor Afiqah Rahmat, Siti Hidayah Muhad Salleh
  Pages: 179 - 185
  Abstract: This study aims to forecast the new number of positive cases of COVID-19 using the logistic map, where the presence of chaos is determined using the 0-1 Test. There are a small number of investigations on chaos utilizing the 0-1 Test and logistic map in the literature. This study provides a straightforward technique of forecasting and a current way of determining chaos. Information on new confirmed COVID-19 cases and population of ten countries involving China, Vietnam, Korea, Malaysia, Singapore, New Zealand, India, USA, Brazil, and Mexico for six months from January 20 to June 15, 2020, are selected as samples. The logistic map runs through three stages: data training, forecasting, and validation using the Mean Absolute Error method (MAE). The data training procedure is critical for determining the best growth rate, r, for the logistic map. In chaotic investigations of the 0-1 Test, there appears to be an inverse expectation toward a logistic map. The 0-1 Test in the data of new confirmed COVID-19 cases in all the selected countries reveals the presence of non-chaotic. This contrasts with the existence of chaos in the logistic map forecasts for the USA, Brazil, and Mexico. Regardless, the logistic map was found to be capable of forecasting new COVID-19 positive cases with low error instances. Beginning in the middle of May 2020, new COVID-19 positive cases are forecasted to be on the rise in the USA, Brazil, and Mexico.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.179-185
  Issue No: Vol. 7, No. 2 (2022)
Antifungal Analysis of Papaya Seed Extracts and Biosynthesized Silver
Nanoparticles
- Authors: Tri Lestari Simangunsong, Ananda Putra, Sahna Ferdinand Ginting, Fiska Maya Wardhani, Hairus Abdullah, Refi Ikhtiari
  Pages: 186 - 194
  Abstract: The purpose of research is to investigate the antifungal potential of papaya seed extract and the biosynthesis of silver nanoparticles by C. papaya extract. Here we report 14 secondary metabolites from C. papaya seed extract detected by gas chromatography mass spectroscopy. Bioactive components were majority classified as fatty acid-methyl ester, heterocyclic amides, and phenolic compounds. The proposed mechanisms of those metabolites on inducing antifungal activity were comprehensively studied. We found that the n-hexane fraction was the solely fraction to produce the silver nanoparticles. Scanning electron images presented the aggregation and evenly distribution of spherical silver nanoparticles. The XRD exhibited the crystallization of the bio-organic synthetic phase based on the specific spectrum of 2-theta at 38.9 degree with miller index [1,1,1]. The particle size analyzer also confirmed the nanoscale of synthesized materials as in the average size of 92.1 nm (Z) and 0.406 (PI). Antifungal effects were examined by disc diffusion method upon each fraction with varying concentrations of 25%, 50%, 75%, and 100% (w/w) against C. albicans. ANOVA analysis showed no significant difference among all fractions tested (p > 0.25). The antifungal activity was categorized as a moderate effect with the mean of inhibition zone ranging from 6.1 to 6.8 mm. However, the potential of papaya seed extract is relatively better than the papaya leaves extract, as previously reported. We suggest further studies on the molecular docking of the secondary metabolites against nanoparticle, and specific biomolecular analysis according to the mechanism of action.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.186-194
  Issue No: Vol. 7, No. 2 (2022)
The Enhancement Solubility and Stability of Erythromycin Formatted in
Solid Lipid Nanoparticles by Utilizing PVA as Stabilizer
- Authors: Mardiyanto, Budi Untari, Najma Fithri Annuria, Ady Mara, Andre Agung Aprianto, Gustina Emilia Ningsih
  Pages: 195 - 201
  Abstract: Infectious diseases have changed the world order today where the infection is the main cause of illness and death in the world. Erythromycin is a macrolide antibiotic that can generally inhibit the growth of Staphylococcus aureus and resistant strains. The free molecule of erythromycin in the part of the body does not reach Staphylococcus aureus because it is degraded by the first-pass effect. Nanoparticles can minimize damage to active substances due to first-pass effects because the particles have been protected by biopolymers leading to the minimizing damage of active substances. Formulation of nanoparticles loading erythromycin was used with the following variations in the amount of erythromycin 25 to 100 mg. Erythromycin was formulated by the coated polymer to changes the physics of the erythromycin into a particle. Preparation of erythromycin into nanoparticles was utilized stearic acid polymer, PEG-400, and polyvinyl alcohol using hot homogenization and ultrasonication method. Results showed that the optimum formula was the second formula (F2) with a percentage of encapsulation efficiency of 80.89773±0.11364. The results of the characterization of submicron particle formation such as morphology, diameter (particle size) and distribution (PDI) of F2 were spherical 518.6 nm; 0.096 PDI; and a zeta potential value of -12 mV respectively. The particles loading erythromycin were successfully increasing the stability of erythromycin for up to 5 cycles in terms of the heating-cooling-cycles test and also the solubility in SIF.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.195-201
  Issue No: Vol. 7, No. 2 (2022)
Preparation and Evaluation of Antihypercholesterolemic Activity of
Atorvastatin Calcium-Maleic Acid Co-Amorphous Solids
- Authors: Yudi Wicaksono, Shofiatul Izzah Al Amaliyah, Finas Rahmayanti, Viddy Agustian Rosidi, Lina Winarti, Dwi Setyawan
  Pages: 202 - 207
  Abstract: Atorvastatin calcium is a statin drug used for antihypercholesterolemic. The oral bioavailability of atorvastatin calcium is relatively low because it is poorly soluble in water. The low oral bioavailability of the drug causes a decrease in its therapeutic effectiveness. This study aimed to increase the solubility of atorvastatin calcium through the formation of co-amorphous solids and evaluate its activity as antihypercholesterolemic. Atorvastatin calcium was prepared into co-amorphous solids with a maleic acid coformer using the spray drying method. Solids characterization was carried out using Powder X-Ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Fourier Transforms Infra Red (FTIR), and Scanning Electronic Microscopy (SEM). The solubility test was carried out using the shaking method, while the evaluation of antihypercholesterolemic was carried out in vivo in experimental animals. The results of the analysis of diffractograms, thermograms, FTIR spectra, and micrograph images showed that the atorvastatin calcium-maleic acid solids prepared by spray drying were a co-amorphous solid. The atorvastatin calcium-maleic acid co-amorphous solids had a greater solubility in water (p<0.05) when compared to pure atorvastatin calcium. However, the in vivo antihypercholesterolemic activity results in experimental animals showed that the cholesterol-lowering activity of the atorvastatin calcium-maleic acid co-amorphous solidswas not significantly different (p>0.05) with pure atorvastatin calcium. This phenomenon is thought to be because atorvastatin calcium from co-amorphous solids in solution is more present as a charged fraction, affecting the permeability and absorption process.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.202-207
  Issue No: Vol. 7, No. 2 (2022)
Preparation and Application of Nickel Electroplating on Copper (Ni/EC)
Electrode for Glucose Detection
- Authors: Muh. Supwatul Hakim, Haryoko Pangestu, Riyanto
  Pages: 208 - 212
  Abstract: An electrode of the nickel electroplating on copper (Ni/EC) has been prepared for a simple and low cost glucose sensor in human urine detection. The electrode was prepared by using pure copper (99.9%) with electroplating method in NiSO4 solution. The electrochemical oxidation of Ni/EC electrode was investigated bys using cyclic voltammetry method. Material Ni/EC identification of morphology used Scanning Electron Magnetic (SEM) and Energy Dispersive X-Ray (EDX). The electrochemical reaction of glucose was analyzed by the cyclic voltammetry method in some electrolyte solutions. Calibration curved was constructed and a linear response for glucose concentration at range 0-0.004 M with R2 = 0.992, LOD and LOQ was determined 4.85x10−4 M, 1.6x10−3 respectively. The proposed electrode might open up a new possibility for the determination of glucose concentration in human urine. Its advantages are simple to prepare, low cost analyzing, and excellent results.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.208-212
  Issue No: Vol. 7, No. 2 (2022)
A Comparative Study of Photobiological and Photophysical Characteristic of
Meso-Tetraphenylporphyrin and Meso-Tetraphenylchlorin as Photosensitizers
for Photodynamic Therapy
- Authors: Asmiyenti Djaliasrin Djalil, Susanti, Fuji Marsela Erlita, Ari Fariz Mustafa, Alwani Hamad, Suwandri
  Pages: 213 - 219
  Abstract: Photosensitizer modifications are needed to improve the performance of Photodynamic Therapy (PDT) for the treatment of cancer. This work appraised the photophysical and photobiological characteristics of tetrapyrrolic macrocycles. Meso-tetraphenylporphyrin (m-TPP) and meso-tetraphenylchlorin (m-TPC) represent non-reduced and reduced pyrrole rings tetrapyrrolic macrocycles, respectively. The absorption spectra of m-TPP and m-TPC were performed. The relative quantum yield of singlet oxygen (ΦΔ) was measured at two different pH (6.3 and 7.4) relative to chlorine e6. Dark toxicity was monitored using the MTT assay on breast cancer T47D and NIH 3T3 cell lines. In addition, the stability of the compounds under indirect sunlight was also observed. The absorption maxima of the Q1 band of both compounds are at a longer wavelength. The Q1 peak of a reduced pyrrole ring is more intense than the non-reduced pyrrole ring with the lowest energy transition undergoing a redshift. The singlet oxygen generations are higher at pH 7.4 for both compounds with them-TPC showed a higher relative singlet oxygen quantum yield. In addition, the photosensitizers are stable under indirect sunlight radiation. m-TPC has higher cellular uptake than m-TPP in both cell lines. The dark toxicity of m-TPC is higher than m-TPP in T47D cells. However, the opposite occurred in observing dark toxicity in the NIH 3T3 cell line. Our study concludes that the cellular uptake and ΦΔ can be enhanced by reducing the pyrrole ring of the tetrapyrrole macrocycle. Therefore, m-TPC proved to be a better photosensitizer than m-TPP.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.213-219
  Issue No: Vol. 7, No. 2 (2022)
Tritirachium oryzae and Other Endophytic Mediated Jambu Bol (Syzygium
malaccense) are Potential as an Antioxidant
- Authors: Yustina Hapida, Elfita Elfita, Hary Widjajanti, Salni
  Pages: 220 - 227
  Abstract: Natural bioactive substances have been discovered produced of intracellular fungi. Intracellular fungi, as well as endophytic fungi, it can be found in organs are leaves, stems, roots, fruits, flowers, and seeds. This study aimed to specify for antioxidant activity of intracellular fungi Jambu Bol (Syzygium malaccense) mediated and identify secondary metabolites compounds. The liquid culture was partitioned with ethyl acetate solvent. Using chromatographic techniques, extracts were separated from their secondary metabolites with antioxidant activity apply the DPPH procedure. Its chemical structure was determined using NMR spectroscopic research, and endophytic fungi were recognized using phenotypic characteristics and molecular classification. The endophytic fungus isolation yielded four isolates: YF11, YF12, YF13, and YF14. YF12, with an IC50 of 53.03 g/mL, was the fungus that exhibited good antioxidant activity. Pure chemical secondary metabolites compounds were identified as 2-(4-hydroxyphenyl)-4-methoxytetrahydrofuran-3-ol. Tritirachium oryzae was identified as the endophytic fungus YF12 based on morphological studies and a phylogenetic tree. To boost its antioxidant activity, more study is needed to perform a semi-synthetic reaction on this pure molecule
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.220-227
  Issue No: Vol. 7, No. 2 (2022)
Dynamic Modeling and Forecasting Data Energy Used and Carbon Dioxide (CO2)
- Authors: Edwin Russel, Wamiliana, Nairobi Saibi, Warsono, Mustofa Usman, Jamal I. Daoud
  Pages: 228 - 237
  Abstract: The model of Vector Autoregressive (VAR) with cointegration is able to be modified by Vector Error Correction Model (VECM). Because of its simpilicity and less restrictions the VECM is applied in many studies. The correlation among variables of multivariate time series also can be explained by VECM model, which can explain the effect of a variable or set of variables on others using Granger Causality, Impulse Response Function (IRF), and Forecasting. In this study, the relationship of Energy Used and CO2 will be discussed. The data used here were collected over the year 1971 to 2018. Based on the comparison of some criteria: Akaike Information Criterion Corrected (AICC), Hannan-Quin Information Criterion (HQC), Akaike Information Criterion (AIC) and Schwarz Bayesian Criterion (SBC) for some VAR(p) model with p= 1,2,3,4,5, the best model with smallest values of AICC, HQC, AIC and SBC is at lag 2 (p= 2). Then the best model found is VECM (2) and further analysis such as Granger Causality, IRF, and Forecasting will be based on this model.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.228-237
  Issue No: Vol. 7, No. 2 (2022)
Insecticidal Activity, Toxicity, Resistance and Metabolism of Pyrethroids:
a Review
- Authors: Ashutosh Singh, Abhishek Singh, Preeti Singh, Archana Chakravarty, Akhilesh Singh , Priti Singh, Mahendra Kumar Mishra, Vivek Singh, Atul Kumar Srivastava, Himanshu Aggarwal, Suresh Sagadevan
  Pages: 238 - 250
  Abstract: Pyrethroids are synthetic or man-made versions of natural pyrethrins discovered in the flowers of a plant species of the Compositae family called "Chrysanthemum cinerariaefolium". The plant was transported into Europe and America after it was discovered in the Near East. Commercial insecticides such as pyrethrin and synthetic pyrethroid are available. These are used to control agricultural pests as well as non-agricultural insects. They are also commercially used in personal care items such as shampoo and as a scent in insect repellent to boost efficacy and persistence in the environment, these insecticides are frequently combined with additional chemicals in diverse formulations, known as synergists. Nerve toxins, known as pyrethroids, although their chemical mechanism of action is unknown. Pyrethroids are neurotoxins, which interfere with the messages sent along nerves by maintaining sodium and chloride channels in an open position. This review presents perspectives, commercial uses and other useful characteristics features of pyrethroids based on human benefits and environmental friendly
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.238-250
  Issue No: Vol. 7, No. 2 (2022)
Facility Location Problem of Dynamic Optimal Location of Hospital
Emergency Department in Palembang
- Authors: Robinson Sitepu, Fitri Maya Puspita, Ide Lestari, Indrawati, Evi Yuliza, Sisca Octarina
  Pages: 251 - 256
  Abstract: The Emergency Department (ED) is one part of a hospital that provides initial treatment for patients who suffer from illness and injury, which can threaten their survival. The importance of integrated care in the ED is one of the keys to successfully treating patients at an advanced level. This becomes complex because the ED works in a team consisting of various multi-disciplinary sciences and limited human resources, facilities, and infrastructure. In the City of Palembang, 23 hospitals have emergency room facilities from 18 Sub-Districts, by using the TOPSIS (Technique for Others Reference by Similarity to Ideal Solution) method to vary the distance (radius) the optimal location of the emergency department is obtained according to the number of hospitals that have emergency room facilities, namely Ilir Timur I District, Ilir Barat I District, Sukarami District, and Plaju District. Based on the formulation of the p-median model and the completion of the TOPSIS method, the order of Districts that have optimal locations from 18 Sub-Districts that have emergency department facilities in the City of Palembang is obtained.
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.251-256
  Issue No: Vol. 7, No. 2 (2022)
Optimization of Liquid Smoke from Shorea pachyphylla using Response
Surface Methodology and its Characterization
- Authors: Hasan Ashari Oramahi, Kustiati, Elvi Rusmiyanto Pancaning Wardoyo
  Pages: 257 - 262
  Abstract: The present study aims to optimize the processing variables producing liquid smoke from mabang wood (Shorea pachyphylla) by using Response Surface Methodology (RSM). In this investigation, a design of experiment with different combinations of pyrolysis temperature and pyrolysis time on the liquid smoke yield from mabang wood was applied. The response of the optimal yield, temperature, and time of pyrolysis was predicted using a mathematical model. The optimal operating conditions for the process of yielding 31.31% liquid smoke were identified at the pyrolysis temperature of 440◦C and pyrolysis time of 124 minutes. The effect of pyrolysis temperature was more significant than the pyrolysis time (p<0.05). The liquid smoke samples were evaluated by a GC-MS. The main chemical compound of the liquid smoke were 1,2-ethanediol (19.26%), fluoromethane (6.69%), formic acid (4.96%), 2-propanone (4.17%), acetic acid (18.64%), acetol (4.80%), furfural (9.94%), 2,4-hexadecanoic acid (3.45%), and guaiacol (2.93%).
  PubDate: 2022-04-19
  DOI: 10.26554/sti.2022.7.2.257-262
  Issue No: Vol. 7, No. 2 (2022)