Indonesian Journal of Chemical Studies

Analysis of The Impact of Handwashing with Soap Policy on Water Quality in Public Facilities: A Case Study in Palangka Raya, Indonesia

Achmad Imam Santoso — 2023-07-29

Coronavirus disease 2019 (Covid-19) has changed lifestyles. One of the new habits practiced by the community is washing hands. The government had issued a policy stipulated in the decree of the Minister of Health of the Republic of Indonesia number HK.01.07/Menkes/382/2020 concerning Health Protocols for Communities in Public Places and Facilities in the Context of Prevention and Control of Covid-19. Washing hands with soap is an effective step to break the chain of transmission of Covid-19. This research obtained samples of handwashing disposal and surface water at three public facilities in Palangka Raya city, i.e. G. Obos XX market, Pasar Besar, and KPD Supermarket that examined for the parameter of BOD, COD, TSS, and detergent content in the area. The result was the handwashing disposal and the surface water of three public facilities had BOD, COD, TSS, and detergent levels exceeding the surface water quality standard. Disposal of handwashing with soap waste directly into surface water causes a decrease in surface water quality

Synthesis and Characterization of Isopropylidene Glycerol Acetate and Isopropylidene Glycerol Propanoate Compounds

Achmad Ridlo — 2023-10-23

Isopropylidene Glycerol Acetate (IGA) and Isopropylidene Glycerol Propanoate (IGP) as ester compounds using acetic and propanoic acids have been synthesized, characterized, and studied for their antibacterial properties. The IGA was synthesized from ethyl acetate (EtOAc) and 1,2-O-isopropyliden glycerol (IPG) with a mole ratio of 1:8 through a transesterification reaction. Meanwhile, the IGP was synthesized using ethyl propanoate (EP) with the same ratio and method as IGA. All materials in this study were identified using FT-IR, GC-MS, ¹H-NMR, and ¹³C-NMR. The characterization results indicated that the compounds of EP, IPG, IGA, and IGP had been successfully formed and identified. It was also revealed that the compounds of EP, IPG, IGA, and IGP were successfully synthesized with yields of 37.72, 27.78, 70.11, and 63.83%, respectively. The antibacterial activity test revealed that neither IGA nor IGP inhibited the growth of Staphylococcus aureus or Escherichia coli at concentrations of 62.5; 125; 250; 500; and 1000 ppm. Therefore, it was asserted that ester compounds synthesized with short-chain carboxylic acids, such as propanoic and acetic acids, lacked antibacterial properties.

Comparative Analysis of Electronic Structures Calculations: A Simple Test Case Set for Kohn-Sham Density Functional Theory and Hartree-Fock Methods

Yusuf Bramastya Apriliyanto — 2023-11-10

A comparative analysis on the performance of Kohn-Sham density functional theory (KS-DFT) and Hartree-Fock (HF) methods to obtain reliable energy and electronic properties has been performed in this study using a simple test case. It is crucial to re-emphasize the key differences between these methods to address common conceptual difficulties that occur among freshmen studying basic computational chemistry. The results suggested that the eigenvalue theorem in determining ionization potential could be well implemented in the HF but not in the KS-DFT method. The total energy difference between ionized and non-ionized species was an appropriate procedure to calculate the first ionization potential within the KS-DFT method. The HOMO-LUMO gap in the HF was larger than the gaps obtained from the KS-DFT method. Among all of the performed calculation methods, the B3LYP hybrid functional provided better total energy where the eigenvalues were located between the HF and the LDA/GGA functionals.

Chemicals Analysis of Drilled Ground Waters in Moa Island, Maluku, Indonesia

M. Sulthon Nurharmansyah Putra — 2023-12-04

Moa Island is one of the remote Indonesian Islands that face the difficulty in accessing clean water, especially during the dry season. One way to get clean water is by drilling for groundwater. The drilled groundwater in Kaiwatu Village on Moa Island, Southwest Maluku Regency, Maluku Province, was analyzed for its content to obtain primary data. Primary data related to the quality of drilled groundwater sources includes chemical, physical, and microbiological parameters. The results of chemical parameters obtained from the test results were <0.01 mg/L fluoride, total chromium, nitrite, nitrate, iron, manganese, zinc, cyanide, lead, <0,001 mg/L cadmium, 17.9 mg/L hardness, sulfate 147.55 mg/L, pH 7.50, and organic substances 2.8 mg/L. The physical parameter analysis showed a turbidity level of 3.71 NTU, a temperature of 26.8 °C, and a color of 5 TCU. The microbiological parameters obtained by the analysis were 0/100 mL. Primary data was then compared with secondary data, namely environmental health quality standards and air health requirements from Minister of Health Regulation No. 32 of 2017 for chemical and physical parameters, as well as water quality requirements and monitoring from Minister of Health Regulation 416/MENKES/IX/1990 for microbiological parameters. The analysis results using a comparison of primary and secondary data showed that all parameters contained in the primary data had values below the safe limits set by the requirements in the secondary data.

Spray Gel Formulation of Ethanolic Extract Senduduk Leaves (Melastoma malabatricum) Against Antioxidant Activity, SPF, and Chemical Components Analysis with LC-MS/MS

Rizky Yulion — 2023-12-21

Senduduk leave (Melastoma malabathricum) is one of the species in the melastomaceae family that has long been used by local Indonesian people, one of which is the Suku Anak Dalam (SAD) for various needs and also as traditional medicine. The study aimed to examine the antioxidant activity of ethanolic extract of senduduk leaves. The extract was then formulated into spray gel preparations as UV-B sunscreen. The research method used was starting from sampling, determination, making samples, soxhlet, determining the IC₅₀ value, spray gel preparation formulation, formulation stability test, measuring sun protection factor (SPF) values, and identifying extract chemical components with the LC-MS/MS instrument. The results was that the ethanolic extract of senduduk leaves had an IC₅₀ value of 49.73 μg/mL with the best SPF value at a concentration of 70 ppm, which is 19.98. Spray gel preparations with a concentration of 70 ppm have an IC₅₀ value of 44.22 μg/mL, an SPF value of 24.96, and a potent antioxidant intensity. So, extract spray gel can potentially have activity as antioxidants and can be used as UV-B sunscreen. The compounds identified include quercetin, quercitrin, DEET, n-boc-3-pyrrolidinone, medicarpine, taxinine, and other compounds. The ethanol extract of the soxhlet results showed more promising results for further tests of in-vitro, in-vivo, and in-silico bioactivity studies.

Detection of Hexavalent Chromium Ion in Water by Optode Membrane

Zulhan Arif — 2023-12-27

Chromium is a heavy metal that is often found as a water pollutant. High concentrations of hexavalent chromium (Cr(VI)) ion in nature are toxic and carcinogenic, so their presence in water needs to be monitored. Detection of heavy metals in water was carried out using an optical sensor membrane (optode). The optode was fabricated from cellulose triacetate polymer with plasticizers (oleic acid and acetophenone), aliquot 336, and the chromoionophore 1.5-diphenylcarbazide (DPC). The success synthesis of optode was evidenced by FTIR and SEM characterization. The optode performance produces a linear response in detecting Cr(VI) ion in the concentration range of 0.02-0.40 mg/L with an R² of 0.9930, as well as the best conditioning at pH 3. The detection and quantitation limits are 0.0055 mg/L and 0.0165 mg/L. The sensitivity of the chromium optode was excellence, with a molar absorptivity value of 8.8303 × 10⁶ M^-1cm^-1. The performance test results of the chromium optode were acceptable because they meet the specified requirements for minimum detection concentration value.