Stannum : Jurnal Sains dan Terapan Kimia <p>Jurnal Sains dan Terapan Kimia published research article, minireview/review, and short communication that included studies in Inorganic Chemistry, Organic Chemistry, Analitycal Chemistry, Biochemistry, Physical Chemistry, Computational Chemistry, Chemical Engineering, and Applied Chemistry</p> Department of Chemistry - Universitas Bangka Belitung en-US Stannum : Jurnal Sains dan Terapan Kimia 2714-674X Phytochemical Analysis and Antifungal Activity of Phoebe excelsa Nees Leaf Extract <p>Candidiasis is an infection caused by the fungus <em>Candida albicans</em>. Candidiasis was recorded in the second highest position as an infectious disease that accompanies HIV/AIDS, as many as 266 cases. Candidiasis is the highest infection caused by fungi and is opportunistic. Infections caused by candida albicans can generally be treated with antifungal medications. However, the use of drugs in the long term can cause resistance to these drugs, besides antifungal drugs can also cause various side effects. Therefore, in this study, an assessment of the phytochemicals of the ethanol extract of medang sang’s leaves and its bioactivity as antifungal <em>Candida albicans</em> will be carried out. Testing the content of secondary metabolites in medang’s leaves was carried out qualitatively by observing changes in the sample when reacted with reagents. Testing the antifungal activity of the ethanol extract of medang sang’s leaves was carried out in-vitro using the disc diffusion method. Results Based on the test, the ethanol extract of medang sang’s leaves contains alkaloids, flavonoids and tannins. The results of testing the antifungal activity of <em>Candida albicans</em> showed no inhibition, this was because the tang compound contained in the ethanol extract of medang sang’s leaves did not have antifungal activity against <em>Candida albicans</em>.</p> Anis Nurohma Occa Roanisca Ristika Oktavia Asriza ##submission.copyrightStatement## 2022-05-28 2022-05-28 4 1 1 5 10.33019/jstk.v4i1.2484 Utilization of Adsorbent Cocoa Shell For Purification of Used Cooking Oil <p>Cooking oil, triglycerides that is liquid at room temperature, is one of important foodstuffs. Repeated use of cooking oil might decrease the quality of the oil and leads to negative impacts on health. An alternative method to treat used cooking oil is adsorption with cacao shell. This present study aims to find out the influences of adsorbent and size variation of cacao peels as the adsorbent on the reduction of free fatty acid, peroxide numbers and water content in used cooking oil. The test parameters of this study were the reduction of free fatty acids by alkalimetric titration; peroxide number by iodometric titration; and content of water by oven-drying method. In the present study, cacao nibs were used as an absorbent to reduce the levels of free fatty acid, water, and peroxide number with variety sizes of the particle, such as 100 mesh and 120 mesh: and 8-hour contact time. The results of the present study indicated a decrease in free fatty acid from 0,448% to 0,327% dan 0,278%; the initial water content of 0,020% decreased to 0,010% and 0,009%; the peroxide number changed from 15,3 meq O<sub>2</sub>/kg to 3,25 meq O<sub>2</sub>/kg and 1,25 meq O<sub>2</sub>/kg. Based on the results, the absorbent that has the optimum adsorption is the 120 mesh particle size of adsorbent.</p> Rini Marlina Ade Oktasari Rohmatullaili Rohmatullaili ##submission.copyrightStatement## 2022-05-28 2022-05-28 4 1 6 12 10.33019/jstk.v4i1.2638 Determination of Chemical Oxygen Demand (COD) Concentration in Domestic Wastewater Using UV-Vis Spectrophotometry Method Based On The Effect Of Reflux Time And Preservation Time <p>The purpose of determining Chemical Oxygen Demand (COD) in samples of domestic wastewater is to determine the effect of variations in the reflux process time which is set to 0, 30, 60, 90, and 120 minutes as well as with variations in the testing time which are set to 0, 3, and 7 days. Determination of LOD and LOQ using a UV-Vis Spectrophotometer was also carried out and the regression equation y = 0.0003x + 0.0066 with a coefficient of determination (R2) was 0.998 with LOD and LOQ values ​​respectively 40.0416 mg O2/L and 133.4721 mg O2/L. Determination of the effect of reflux time and preservation time on COD levels was carried out statistically, namely the normality test (Kolmogorov-Smirnov Test) and homogeneity test (Levene Test) ending with a two-way ANOVA test with a probability or significance value of the inlet and outlet samples of 0.000 &lt; 0.05 ( ). Reflux time affects COD levels, the longer the reflux time, the higher and more stable COD levels. Preservation time affects the decrease in COD levels, which is the longer the preservation time, the greater the decrease in COD levels.</p> Muhaimin Muhaimin Renaldy Ajie Prayoga Endah Eniati ##submission.copyrightStatement## 2022-05-28 2022-05-28 4 1 13 18 10.33019/jstk.v4i1.2866 Characterization of Cassava (Manihot esculenta Crantz) Peel Activated Carbon based on Impregnation Ratio and Activation Temperature <p>Cassava peel is a natural material that is still underutilized even though has the potential as an alternative to activated carbon precursors. In the synthesis of activated carbon, the impregnation ratio and activation temperature are important factors that affect the characteristics of the activated carbon produced. This study aims to determine the effect of variations in the impregnation ratio (carbon: H<sub>3</sub>PO<sub>4</sub>) and activation temperature on the characteristics of activated carbon from cassava peel (CPAC) and to determine the optimal conditions in the manufacture of CPAC. In this study, CPAC was produced by treatment with various impregnation ratios of 1:5, 1:6, 1:8, 1:10, and 1:12 (w/w, carbon: H<sub>3</sub>PO<sub>4</sub> 30%) and a range activation temperature variation of 400 - 800 °C in the furnace for 60 minutes. The CPAC results were analyzed using FTIR, XRD, and SEM-EDX instruments. Based on the results of the FTIR test, it is showed that the characteristics of CPAC contain functional groups O–H, C–H, C≡C, C=C, C–O/P=O with an impregnation ratio of 1:6 (w/w, carbon: H<sub>3</sub>PO<sub>4</sub> 30%) and an activation temperature of 500 °C for 60 minutes to be the optimal conditions in the production of CPAC. The CPAC has an amorphous crystalline character based on XRD analysis and a hollow (porous) surface based on SEM analysis. The results of the EDX test showed that CPAC consisted of the elements carbon (C), oxygen (O), nitrogen (N), phosphate (P), sodium (Na) with the respective percentages being 72.60%, 15.52%, 10 .32%, 1.09%, and 0.47% respectively.</p> Blessy Yemima Andiani Cucun Alep Riyanto Yohanes Martono ##submission.copyrightStatement## 2022-05-28 2022-05-28 4 1 19 26 10.33019/jstk.v4i1.2533 Separation of Chromium(VI) Metal in Wastewater Using Electrocoagulation Method with NaCl Coagulant <p>Waste has become an environmental problem that needs attention in its handling. Metal Cr (VI) is one of the components of a very dangerous pollutant produced by industrial activities, such as textiles. In fact, there are still many textile industry players who do not treat their waste because they feel that the processing requires expensive upfront costs. Therefore, this research was conducted to perform a sewage treatment system with a separation technique using an alternative method, namely electrocoagulation using NaCl coagulant. The research was conducted at the Laboratory of Applied Chemistry and Toxicology at the Rajawali Health Institute. The sample used is a sample of liquid waste taken directly from a textile industry in Bandung, Indonesia. The results showed a decrease in the levels of Cr (VI) after the electrocoagulation process until it reached a percentage value of 64.02%. Based on this, it can be said that the electrocoagulation method is effective enough to be used as a simple treatment technique to reduce the levels of Cr (VI) metal in wastewater.</p> Farhan Baehaki Wasiyah Khusna Fadhilah Mila Karmila ##submission.copyrightStatement## 2022-05-28 2022-05-28 4 1 27 33 10.33019/jstk.v4i1.2924 Antibacterial Activity of Ethyl Acetate Fraction of Methanol Extract Leaves of Orange Leaves (Filicium Decipiens) Against Staphylococcus epidermis <p>The Filicium decipiens (umbrella sunshade) tree, known as ormo kiara ormo or ki soap, belongs to the Sapindaceae family, namely saponin-producing plants which are estimated to have high levels of saponins and toxicity. This study aims to determine the antibacterial activity of the ethyl acetate fraction of parasol leaves against Staphylococcus epidermidis. The extract was macerated using methanol as a solvent. The results of phytochemical screening showed that the parasol leaf contains phenolic compounds, flavonoids, alkaloids, saponins, tannins and steroids. Then proceed with the fractionation process of parasol leaf extract to obtain the n-hexane fraction with liquid:liquid partition using water:ethyl acetate = 1:1 as solvent. The antibacterial activity was tested using the disc diffusion method (Kirby and Bauer diffusion). The concentration variations of the n-hexane fraction were 25%, 50%, 75%, 100%, control (+) cifroploxacin and control (-) DMSO. The highest concentration results were shown at a concentration of 75%, namely 12.52 and a decreasing concentration of 25%, namely 11.12, 100% concentration, 11.02, and 50% concentration, which was 10.62. While the concentration of K(+) namely Cifrofloxacin was 31.95. And shows that the largest concentration is targeted by a concentration of 75% which is 12.52.</p> Afri Abdiansyah Reh Malem Br Karo Windi Wildani Wardah Fitriah Tanjung ##submission.copyrightStatement## 2022-05-28 2022-05-28 4 1 34 39 10.33019/jstk.v4i1.2884