KOVALEN: Jurnal Riset Kimia
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Validasi Metode Penetapan Kadar Logam Kadmium (Cd) dalam Sampel Tanah Menggunakan Spektrofotometer Serapan Atom (SSA)-Nyala: Validation of the Method Determination of Cadmium Metal (Cd) Using Flame Atomic Absorption Spectrophotometer (AAS)
Get PDFSoil has an important role in life on earth because it supports plant life by providing nutrients and water as well as supporting roots. One of the chemical elements that cause pollution is cadmium. The standard method for analyzing the content of cadmium metal in the soil is using a Flame Atomic Absorption Spectrophotometer (AAS) referring to SNI 8910:2021. This method changes the weight content from one gram to five grams of sample to obtain cadmium metal levels that can be detected by the instrument. Therefore, this method needs to be validated before being used for routine analysis in the laboratory. The validation parameters are linearity, precision, accuracy, method detection limit, and robustness. The Validation results were obtained for the linearity parameter correlation coefficient value of r = 0.999, %RSD repeatability precision parameter of 1.51%, and the intermediate precision was obtained by %RSD analyst 1 : 1.51% and analyst 2 : 0.82%, accuracy parameter obtained the %recovery results were (88.73-97.01)%, the LDM parameter was obtained at 2.03 mg/kg, the robustness parameter was obtained by F-count of 1.25 and F-table of 3.40 which shows the average assay of metals Cd weighing 1, 3, 5, and 8 grams that were not significantly different. Overall, the results of the validation show that the method of assaying cadmium metal using Flame-AAS complies with the acceptance requirements, therefore it can be used for routine analysis in the laboratory
Adsorpsi Ion Pb(II) Menggunakan Silika Berbasis Pasir Alam Takari-NTT : Ion Pb(II) Adsorption Using Silica from Natural Sand of Takari-NTT
Get PDFThis article reported the adsorption of Pb(II) ions using silica extracted from the natural sand of Takari, Timor island, Nusa Tenggara Timur province. The silica was extracted using hydrothermal and coprecipitation methods. The extracted silica was then used for Pb(II) adsorption under several optimization conditions: pH, contact time, concentration, kinetic model, and adsorption isotherm. The determination of Pb(II) concentration used dithizone reagent, forming complexes, and then measured using Uv-Vis. The pH, contact time, and optimum concentration results were 7, 60 minutes, and 80 mg/L, respectively, with an adsorption capacity (qe) of 0.679 mg/g, 0.745 mg/g, and 18.096 mg/g. The kinetic model followed a pseudo-order-2 with R2 = 0.93, and the adsorption isotherm of Pb(II) metal ions followed the Temkin isotherm model. The results showed that the silica extracted from the natural sand of Takari of Timor island-Nusa Tenggara Timur could adsorb Pb(II) metal ion
Analisis Parameter Spesifik dan Nonspesifik Simplisia Daun Bawang Merah (Allium cepa L.): Analysis of Specific and Nonspecific Parameters of Shallot (Allium cepa L.) Leaves Simplicia
Get PDFShallots are natural ingredients that are used as food enhancers for food and traditional medicines. This study aimed to analyze the specific and non-specific parameters of shallot (Allium cepa L.) Simplicia. Analysis of simplicia specific parameters in the form of material identity, organoleptic, macroscopic, and microscopic examination, levels of water-soluble extracts and ethanol soluble extracts while non-specifically in the form of a percentage of drying loss, water content, total ash, acid insoluble ash, and water-insoluble ash. The results of the research on specific parameters gave a yellowish-green simplicia color, a distinctive odor, in the form of powder, macroscopic examination of leeks elongated cylindrical, small round and hollow like a pipe, blunt leaf base, pointed leaf tip, green color, microscopic examination contained cover cells, gaps and epidermal cells, the levels for water-soluble extracts were 8.81±2.12%, the levels of ethanol-soluble compounds were 5.64±2.91%. The results of the study of non-specific parameters, the percentage of drying shrinkage was 0.89±0.57%, water content was 0.89±0.34%, total ash was 12.97±0.34%, acid-insoluble ash was 6.44±2.12%, and the water-insoluble ash content was 8.03±0.84%
Pengaruh Penambahan Minyak Zaitun Terhadap Karakteristik dan Reologi Edible Film Berbahan Dasar Gluten: The Effect of Addition of Olive Oil on The Properties and Rheology of Gluten-Based Edible Films
Get PDFGluten vegetable protein can be used as an alternative source of biopolymer as the basic material for edible film other than polysaccharides. Gluten-based edible films have a poor water vapor barrier and high cohesive and viscoelastic properties, therefore the addition of lipids and plasticizers is required. In this study, olive oil was added to reduce its permeability to water vapor, while glycerin was added to produce a more flexible edible film. The results showed that the addition of 1% olive oil could reduce the lowest water vapor transmission rate of 9.14 g/m2/24 hours with a thickness of 0.248 mm, tensile strength of 16.64 mPa, and elongation of 419.5%. The four characteristics are in accordance with the Japanese Industrial Standard. The antimicrobial testing on edible films showed that the addition of 0-2% olive oil could inhibit the growth of E. coli, while A. niger and R. oryzae 0-2% olive oil could not inhibit the growth of the two fungi. The measurement of optical properties showed that the transparency of the edible film was highest at the addition of 0% olive oil at 55%. The highest opacity value was with the addition of 1% olive oil, which is 2.96. The Fourier Transform Infrared (FTIR) identification showed that the edible film added with 1% olive oil had three characteristic absorption bands from gluten, olive oil, and an absorption band from glycerin. These bands indicate that olive oil, glycerin, and gluten do not react but only physically interact. The measurement using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS) showed that the microstructure of gluten-based edible film produces a varied structure where the gluten structure network can be clearly observed and contains elements of C, O, N where the intensity of C and O elements of 160-400 cps and 30-100 cps, respectively
Analisis Kadar Merkuri (Hg) pada Rambut Pekerja Tambang di Pertambangan Emas Tanpa Ijin (PETI) Kabupaten Parigi Moutong dalam Hubungannya dengan Frekuensi Konsumsi Ikan: Analysis of Mercury (Hg) Levels in Hair of Gold Miners at Ilegal Gold Mining Activities of Parigi Moutong Regency in Relation to Frequency of Fish Consumption
Get PDFIllegal gold mining is a mining activity using traditional methods. Mining activities in the traditional way process mining products using the amalgamation process. In the amalgamation process, gold is bound by adding mercury and the waste from the amalgamation process which may still contain mercury is discharged into the environment. It can have an impact on the accumulation of mercury in humans, especially the miners either directly or through the food chain. This study aims to determine the amount of mercury concentration that has accumulated in miners' hair in relation to the frequency of fish consumption. The sampling method is done by random sampling method in five sub-districts in Parigi Moutong Regency. Fish consumption frequency data was taken by filling out questionnaires by respondents (miners). Analysis of mercury content in hair samples was carried out using the Mercury Analyzer NIC MA-3000. The results showed that the concentration of mercury in miners in all sub-districts exceeded the quality standard set by USEPA, which was above 1 mg/Kg. The highest mercury content was found in the miner's hair in Moutong District which was 3.48 mg/kg, while the lowest mercury content was found in the miner’s hair in Kasimbar District which was 1.06 mg/kg. Based on these results, the gold miners in the five sub-districts have been contaminated with mercury. A correlation value above 0.5 indicates a correlation between fish consumption and mercury concentrations in hair, thereby it can be said that the source of mercury exposure to miners can also come from the fish they consume
Potensi Cangkang Telur Ayam dan Cangkang Telur Bebek sebagai Bioadsorben Logam Pb dari Limbah Cair Industri Farmasi: Potency of Chicken Eggshells and Duck Eggshells as Pb Metal Bioadsorbents from Pharmaceutical Industry Liquid Waste
Get PDFThe pharmaceutical industry liquid waste is one of the wastes that have the potential to produce waste containing heavy metals. One of the highest metal contaminants originating from the pharmaceutical industry is lead (Pb). Pb metal can cause health problems and pollute the environment. One way to treat Pb waste is by the adsorption process using bioadsorbent. The eggshell waste can be used as an adsorbent to absorb heavy metals. The eggshell contains calcium carbonate, therefore it can be used as an adsorbent. This study aims to determine the optimum pH, optimum mixing time, and optimum mass of chicken eggshell powder and duck eggshell powder, and to determine the comparison of the effectiveness of adsorption between chicken eggshell powder and duck eggshell powder as bioadsorbent of heavy metal Pb in pharmaceutical industry wastewater by using Atomic Absorption Spectrophotometer (AAS) at a wavelength of 283.3 nm. The results showed that the eggshell samples had the optimum pH at pH 4, the optimum mixing time was 45 minutes, and the optimum mass was 125 mg, with the effectiveness of Pb adsorption of 92.75%. While the duck eggshell samples obtained the optimum pH at pH 2, the optimum mixing time was 30 minutes, and the optimum mass was 125 mg, with the effectiveness of Pb adsorption of 93.66%. Chicken and duck eggshells have the potential to be used as an alternative bioadsorbent in wastewater treatment
Pengaruh Metode Hidrolisis Terhadap Karakteristik Kimia Senyawa Kalsium Hasil Ekstraksi dari Cangkang Telur Ayam: The Effect of Hydrolysis Methods on Chemical Characteristics of Extracted Calcium Compounds from Chicken Eggshells
Get PDFPreparation of calcium compounds such as calcium hydroxide, calcium carbonate, and calcium oxide from chicken eggshells can be done through conventional methods that are cheaper and more practical, such as the sol-gel hydrolysis method and the coprecipitation method. In this study, the synthesis of calcium compounds from domestic chicken eggshells was carried out using two methods: the coprecipitation method and sol-gel method. Coprecipitation method consists of acid hydrolysis and alkaline hydrolysis. Sol-gel method consists of modification I and modification II. The AAS results showed that the calcium content from the hydrolysis of acids, alkaline, sol-gel modification I, and sol-gel modification II: 14.50%, 6.64%, 6.68%, and 9.93%, respectively. The FTIR showed that calcium compounds have four characteristic absorption bands, including O–H (3641.60 and 3448.72 cm-1) derived from Ca(OH)2 and H2O products, C=O (2981.95 - 1799 cm-1), and C–O (1448.54 – 874.68 cm-1) both of which from carbonate ions (CO3-) in CaCO3 both from eggshell and from the resulting calcium compounds, and Ca-O (711.73 cm-1) derived from CaO products. The results showed that the modification ll sol-gel method was the best because calcium compounds consisting of CaCO3, Ca(OH)2, and CaO were produced in a smooth texture, white color, and with the highest calcium content compared to other methods
Potensi Minyak Herbal STIFA Pelita Mas Terhadap Kadar Ureum dan Kreatinin Tikus Kondisi Hiperglikemik: Potency of STIFA Pelita Mas Herbal Oil on Ureum and Creatinine Levels of Rats Hyperglycemic Conditions
Get PDFUtilization of natural preparations is a treatment carried out by the community with the aim of improving health status naturally. Traditional medicine has become an alternative for the community due to the relatively high cost of modern medicine. One of the diseases with a high financing burden is kidney disease, which is after heart and blood vessel disease. This study aims to determine the potential of traditional medicinal preparations of Herbal Oil STIFA Pelita Mas on the state of urea and creatinine concentrations in experimental animals, this research used white male rats divided into six treatments. Determination of urea and creatinine levels was carried out starting from days 1, 7, 14, 21 to 28, then normality and homogeneity tests were carried out, and parametric statistics were analyzed using the one-way ANOVA test. The results showed that the administration of STIFA Pelita Mas Herbal Oil in Formula 1, 2, and 3 had urea levels of 42.60 mg/dL, 28.64 mg/dL, and 51.46 mg/dL, respectively. The average values ​​of creatinine in Formula 1, 2, and 3 were 0.73 mg/dL, 0.63 mg/dL, and 0.92 mg/dL, respectively. The administration of Formula 2 was effective in reducing the concentration of urea and creatinine. Pelita Mas herbal oil preparation can be used as a medicine to improve kidney structure
Evaluasi Kadar Senyawa Fenolat, Flavonoid Total, serta Aktivitas Antioksidan Secara in vitro dalam Ekstrak Metanol Bawang Dayak (Eleutherine palmifolia (L.) Merr : Evaluation of Phenolic Compounds, Total Flavonoid Content and in vitro Antioxidant Activity of Methanol Extract of Dayak Onion Bulbs (Eleutherine palmifolia (L.) Merr
Get PDFDayak onion bulbs are a plant originating from Kalimantan which has been used for generations to treat various diseases. This plant is quite easy to grow and develop in many places in Indonesia. The aims of the present study were to evaluate the antioxidant potential of the methanol extract of Dayak onion bulbs based on the total of the phenolic and flavonoids contents and also the antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging ability, ferric reducing power and total antioxidant capacity. The results showed the total phenolic and flavonoid methanol extract of Dayak onion bulbs were 14.49 ± 1.42 mg GAE/g dry weight and 5.41 ± 1.01 mg QE/g dry weight, respectively. Antioxidant activity as measured by the DPPH, total antioxidant capacity, and ferric reduction assay with IC50 values of 16.95 ± 1.58 μg/mL, 24.22 ± 2.51 µg/mL, and 85.40 ± 16.88 µg/mL, respectively. These results suggest that the methanol extract of Dayak onion bulbs has potential bioactive compounds with good antioxidant activity and can be developed as an effective and safe source of natural compounds for functional food or herbal medicine
Sintesis Bioplastik Ramah Lingkungan Berbasis Pati Biji Durian dengan Filler Selulosa Sabut Kelapa: Synthesis of Environmentally Friendly Bioplastic Based on Durian Seed Starter with Coconut Cellulose Filler
Get PDFConventional plastic has become a concern because it is a problem for the environment. Bioplastics made from starch and natural polymers such as cellulose from coconut fiber can be a solution to these plastic problems. This study aims to synthesize and characterize bioplastics made from durian seed starch with sorbitol as a plasticizer and coconut coir cellulose as a filler. This research consisted of several stages of the procedure including the extraction of durian seed starch, isolation of coco coir cellulose, synthesis of bioplastics, and characterization of bioplastics. Bioplastics are made by the melt intercalation method. The resulting bioplastics were characterized by FTIR and mechanical tests (elastic modulus and tensile strength). In this study, the starch produced was characterized by a yellowish-white color and a rough texture with a yield of 10.95%. Before being used as a bioplastic filler, the coconut coir powder was bleached using H2O2 in a base condition to reduce the presence of lignin and hemicellulose. Based on the FTIR spectrum, the bleaching process was indicated by a decrease in the intensity of the absorption peak at wavenumbers of 1246 cm-1 and 1642 cm-1 which were characteristic absorptions for lignin and hemicellulose. The results of the mechanical test showed that the bioplastic composition with the highest tensile strength and modulus of elasticity was owned by bioplastic with 4% cellulose, namely 7.28 MPa and 0.73 MPa