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Jaya Hardi
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Program Studi Kimia Fakultas MIPA, Uniiversitas Tadulako Jl. Soekarno-Hatta Km. 9, Tondo Palu, 94117
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INDONESIA
KOVALEN: Jurnal Riset Kimia
Published by Universitas Tadulako
ISSN : -     EISSN : 24775398     DOI : https://doi.org/10.22487/kovalen
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry
KOVALEN: Jurnal Riset Kimia is a peer-reviewed journal of chemistry published by the Tadulako University, Indonesia. This journal concern with publishing the original research articles, review articles, and the current issues related to chemistry. Publishing frequency 3 issues per year, in April, August, and December.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 12 Documents
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Search results for , issue "Vol. 9 No. 1 (2023): April Edition" : 12 Documents clear
Pengaruh Penambahan Variasi KJ-CTAB Terhadap Karakteristik ZnO/KJ-CTAB yang Disintesis Menggunakan Metode Impregnasi Basah: Effect of Adding KJ-CTAB Variations Towards Characteristics of Synthesized ZnO/KJ-CTAB Using Wet Impregation Method Azzalina Nur Alviana; Aulia Dewi Rosanti; Rizky Arief Shobirin; Fahmi Hidayat
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16036

Abstract

Semiconductor photocatalysts have great potential in solving environmental problems. The photocatalyst process using a semiconductor is one of the technology to oxidize organic compounds such as dyes. Orange peel (KJ) is one of the adsorbents that have the potential for purification of dyes that increase the photocatalytic activity of ZnO material. This study aims to determine the optimum variation of KJ-CTAB to be added to ZnO material. The results of the synthesis of ZnO/KJ-CTAB varasis 1:25, 2:25, and 3:25 (w/v) using the wet impregnation method were characterized on IR, XRD, SEM, DR-UV, and BET instruments. The results showed that FTIR also showed the presence of ZnO bonds in all samples, C-H in samples varied from 1:25, 2:25, and 3:25 (w/v). The XRD results showed that the percentage of crystallinity decreased and the SEM results showed that ZnO/KJ-CTAB 1:25 had a more homogeneous morphology. Based on the results of DR-UV ZnO/KJ-CTAB 1: 25 (w/v) has a band gap energy value of 3.20 eV which is good for use in photocatalyst processes. BET results show that all samples belong to the mesoporous size.
Sintesis dan Karakterisasi Cangkang Kapsul Non Gelatin dari Rumput Laut (Eucheumma cottonii) dan Kaktus Koboi (Cereus peruvianus) untuk Sistem Penghantaran Obat: Synthesis and Characterization of Non Gelatinized Capsule Shells from Seaweed (Eucheumma cottonii) and Koboi Cactus (Cereus peruvianus) for Drug Delivery Systems Micha Mahardika; Ninik Triayu Susparini; Dany Dewaldo; Boima Situmeang; Fauzan Amin
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16098

Abstract

Research on drug delivery systems continues to develop, including making the latest formulations on capsule shells as a medium for drug delivery. The effort that has been done was developing non-gelatine drug delivery materials made from the combination of seaweed and cactus. The main component in making gel on seaweed and cactus is the polysaccharide pectin. This study aims to make and determine the characterization of capsule shells from a combination of seaweed and cactus. Capsule shells are made from a combination of pectin extracts from seaweed and cactus with 5 different ratios of 0:4 (A), 1:3 (B), 2:2 (C), 3:1 (D), and 4:0 (E). The characterization involved weight uniformity test, disintegration time test, water swelling test, and dissolution test. Pectin from green seaweed and koboi cactus weighed 235 g and 75 g. The capsule shell weights based on Farmakope Indonesia sixth edition were 307.2, 311.6, 309.7, 304.6, and 308.7 mg. The capsule shell disintegration times, based on Farmakope Indonesia sixth edition, 2020, were 15,16, 14, 21, and 12 minutes, and the best result of the water swelling test was C capsule (2:2) of 666.7%. The results of the capsule shell dissolution test showed that the reduction of the capsule shells did not exceed 10% for 30 minutes according to the Farmakope Indonesia sixth edition. The capsule shells made from a combination of seaweed and cactus can be used as material in drug delivery systems. Non-gelatinized capsule shell which is expected to have anti-inflammatory activity.
Perbandingan Metode Maserasi dan Microwave-Assisted Extraction pada Daun Beluntas dengan Variasi Pelarut dan Uji Antioksidan: Comparison of Maceration and Microwave-Assisted Extraction on Beluntas Leaves with Variation of Solvent and Antioxidant Test Yudhi Utomo; Nur Chairini; Muhammad Roy Asrori
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16155

Abstract

Beluntas leaves (Pluchea indica L.) as Indonesian herbal plants contain secondary metabolites such as flavonoids. Beluntas leaf parts can be used as medicine. The content of secondary metabolites in Beluntas leaves acts as a natural antioxidant. Beluntas leaf extraction has not been optimal so far. Microwave assisted extraction can increase the yield. This research aims to study the effect of giving different types of solvents of extraction on Beluntas leaves on the levels of flavonoids and the resulting antioxidant activity, and determine the profile of Beluntas leaf extraction results based on comparative trials of the maceration method and MAE (microwave-assisted extraction). This research was conducted in 4 stages: (1) sample preparation of dried Beluntas leaves, (2) extraction by maceration with various types of solvents n-hexane, ethyl acetate, and 70% ethanol, (3) the characteristics of the flavonoid compounds, namely the qualitative test and the quantitative test with AlCl3, and (4) the measurement of antioxidant activity in Beluntas leaf extract using the DPPH method. The results of this study obtained a total flavonoid content of 4.23 mgQE/g which was the result of maceration of the ethyl acetate solvent extract (yield: 5.09%), and all Beluntas leaf extracts in ethyl acetate solvent were included in the category of very strong antioxidant activity with an IC50 value of 31.68 μg/mL.
Analisis Kadar Kurkumin pada Herbal Oil Kunyit Ekstrak Virgin Coconut Oil dengan Metode Ultrasonik dan Maserasi: Analysis of Curcumin Levels in Turmeric Herbal Oil Extract Virgin Coconut Oil with Ultrasonic and Maceration Methods Rif’atul Mahmudah; Ufilia Quthrotun Nada; Sakinatul Aulia
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16178

Abstract

Vegetable oil theoretically and experimentally has proven its potential as an alternative solvent in the extraction of natural materials. Turmeric infused with virgin coconut oil (VCO) is a way to take advantage of the active compounds from the herbs and the oil itself. This study aims to determine the ability of the VCO solvent in extracting curcumin compounds from turmeric with the addition of tween 80 surfactants. The extraction method used was maceration at 60℃ and an ultrasonic frequency of 40 kHz for 15 minutes. Thin layer chromatography (TLC) was used for qualitative analysis of each herbal oil extract using chloroform: methanol (95:5) eluent and FTIR spectrophotometer to identify functional groups. The highest curcumin content was found in herbal oil with tween 80 of 2 ml, namely 31 ppm in maceration extraction and 260.7 ppm in ultrasonic extraction. Identification of curcumin functional groups in herbal oils showed absorption patterns of O-H, C=O, aromatic C=C, C-O-C, and C-H.
Penggunaan Sabut Kelapa Teraktivasi NaOH sebagai Adsorben Metilen Biru: Utilization of Coconut Fiber NaOH-Activated as Blue Methylene Adsorbent Anselmus Boy Baunsele; Erly Grizca Boelan; Aloisius Masan Kopon; Maximus M. Taek; Gerardus D. Tukan; Hildegardis Missa
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16274

Abstract

Methylene blue is a textile dye with carcinogenic and mutagenic properties which can cause various problems for the environment and organisms, therefore it is necessary to treat the waste. This study describes the adsorption of methylene blue using base-activated coconut coir. Coconut coir as waste was prepared into 80 mesh-sized powder and then activated using NaOH solution. The base-activated coconut fiber was then used for methylene blue adsorption under several optimization conditions such as pH, contact time, concentration, and adsorption isotherm. The determination of methylene blue was adsorbed by the adsorbent measured using UV-VIS. The pH and contact time results were 7 and 75 minutes, respectively, with the adsorption capacity (qe) of 1.98 mg g-1 and 99.91%. The isotherm adsorption of blue methylene followed the Langmuir isotherm model with the maximum adsorption capacity (Qmax) of 0.2 mg -1. The result showed that the coconut fiber base activated could be used as a dye adsorbent.
Sintesis dan Karakterisasi Semikonduktor TiO2 Doping Magnesium dengan Metode Hidrotermal: Synthesis and Characterization of Magnesium Doped TiO2 Semiconductor by Hydrothermal Method Tika Paramitha; Khoirunnisa Utami; Yuki Martha Anggraini; Tifa Paramitha
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16275

Abstract

Semiconductors are materials that range between insulators and conductors in terms of conductivity value. Titanium Dioxide (TiO2) is a semiconductor that is widely applied to various things. TiO2 has the benefits, such as being environmentally stable and inexpensive. TiO2 is photoactive in the range of ultraviolet radiation due to the band gap value of 3.2 eV. However, ultraviolet is only produced from 5% of sunlight. The research aimed to narrow the band gap energy so as to maximize light absorption. This is done by modification with the addition of Mg elements to TiO2 materials at different mass variations of Mg (1%, 1.5%, 2%) to the mass of TiO2 which is often referred to as doping. TiO2 was doped by Mg using a hydrothermal method for 24 hours with a temperature of 180ᵒC, followed by 2 hours of calcination at 400ᵒC. Then, TiO2 and Mg-doped TiO2 particles were characterized by SEM-EDX, FTIR, and UV-Vis. Based on the results of TiO2 and Mg-doped TiO2 particle characterization using SEM, both particles are spherical in shape. The success of Mg doping was identified from the data of EDX characterization, which revealed that the mass % of the Mg component increased with the greater Mg doping concentration on TiO2 particles. There was no structural change following Mg doping on TiO2 particles, as evidenced by the same peak based on the results of FTIR characterization of TiO2 and Mg-doped TiO2 particles. Moreover, a 2% Mg mass doping on pure TiO2 resulted in a decrease in band gap energy to 3.16 eV, in which the pure TiO2 was 3.39 eV. The mass doping of Mg on TiO2 required further optimization to obtain the maximum band gap energy reduction for photocatalytic applications.
Aktivitas Antioksidan, Kadar Flavonoid, dan Fenolik Total Cangkang Kerang Mutiara (Pinctada maxima): Antioxidant Activity, Flavonoid Content, and Total Phenolics of Pearl (Pinctada maxima) Clam Shells Khoirul Ngibad; Afidatul Muadifah; Datin An Nisa Sukmawati
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16281

Abstract

Antioxidant compounds are able to dampen or ward off free radicals. Living things including pearl mussels (Pinctada maxima) can produce secondary metabolite compounds (phenolics, alkaloids, and terpenoids). There have been no studies on the antioxidant potential, flavonoid content, and total phenolics of pearl clam shells. This study aimed to determine the antioxidant potential of pearl clam shell ethanol extract (EECKM) in vitro using the DPPH method. In addition, it aims to determine the total flavonoid and phenolic levels of EECKM. The powder of pearl mussel shells is soaked with ethanol and the filtrate is concentrated until a concentrated extract is obtained. Flavonoid and phenolic levels from EECKM were measured using a UV-Vis spectrophotometer. Measurement of antioxidant activity using the DPPH method. EECKM has a yield of 1.73%, flavonoid levels of 0 mg QE/g, and total phenolics of 4.8 mg GAE/g. The extract has the highest antioxidant activity for a concentration of 100 mg / L with a percent value of DPPH radical inhibition of 67.1%.
Analisis Kadar Kadmium (Cd) dalam Bawang Merah Lokal Palu (Allium cepa L. var. aggregatum) pada Berbagai Lokasi dan Umur Tanam: Analysis of Cadmium (Cd) in Palu Local Shallots (Allium cepa L. var. aggregatum) at Various Locations and Planting Ages Eka Lindawati; Khairuddin Khairuddin; Nurhaeni; Ruslan; Ahmad Ridhay; Husain Sosidi; Erwin Abdul Rahim; Syamsuddin
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16287

Abstract

The local Palu shallot (Allium cepa L. var. aggregatum) plant is one of the leading products in the Central Sulawesi region. Shallots can experience a decrease in quality if they are contaminated with heavy metals, such as cadmium (Cd) in amounts that exceed the threshold. This study aims to determine the effect of planting age on cadmium levels in local Palu shallots cultivated in Oloboju Village and Solove Village, Biromaru District, Sigi Regency. The research variables used were the planting age which consisted of 4 levels (age 40, 50, 60, and 70 days), and the planting location which consisted of 2 levels (Solove Village and Oloboju Village). Cd levels were analyzed using an Atomic Absorption Spectrophotometer (AAS). Cadmium levels in shallot roots at two planting locations decreased with increasing planting age, from 101.34 - 107.18 mg/kg at 40 days of age to 1.68-3.78 mg/kg at 70 days of age. Shallot bulbs at two locations had lower cadmium levels than roots, namely 0.01-0.04 mg/kg. The results of the study found that planting time had a significant effect on cadmium levels in the roots of shallots, but planting age and planting location had no significant effect on cadmium levels in local Palu shallot bulbs with levels that met the SNI (Indonesian national standard) quality requirements
Produksi Konsentrat Protein dari Ampas Kelapa (Cocos nucifera L.) Menggunakan NaOH dan (NH4)2SO4 : Production of Protein Concentrate from Coconut Pulp (Cocos nucifera L.) using NaOH and (NH4)2SO4 Hasdinda Hasdinda; Pasjan Satrimafitrah; Syaiful Bahri; Abd. Rahman Razak; Dwi Juli Puspitasari; Indriani; Aini Auliana Amar
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16290

Abstract

Coconut pulp wasted from processed coconut oil has a protein content of up to 18.20%. The potential coconut pulp protein can be processed in protein concentrate which has many benefits. This research was conducted to determine the effect of NaOH and (NH4)2SO4 concentrations in isolating protein and producing protein concentrates that have the highest yield and protein content. Isolation of coconut pulp protein was carried out using NaOH at several concentrations, namely 0, 0.2, 0.4, 0.6, 0.8, and 1 M, while the protein concentrate was prepared using the salting out method with a saturation level of the ammonium sulfate salt of 55%, 60%, and 65%. Analysis of protein content was carried out using the Kjeldahl method. The use of NaOH 0.2 M and (NH4)2SO4 with a saturation level of 60% was the chosen treatment with crude protein content and yield of 75.63% and 33.83%, respectively.
Isotermal Adsorpsi Ion Tembaga (II) Menggunakan Arang Tongkol Jagung (Zea mays L.) Teraktivasi Kalium Permanganat: Isothermal Adsorption of Copper (II) Ions Using Charcoal from Corn Cobs (Zea mays L.) Activated by Potassium Permanganate Lisma Habiba; Nov Irmawati Inda; Prismawiryanti; Husain Sosidi; Ni Ketut Sumarni; Dwi Juli Puspitasari; Moh. Mirzan; Jusman
KOVALEN: Jurnal Riset Kimia Vol. 9 No. 1 (2023): April Edition
Publisher : Chemistry Department, Mathematics and Natural Science Faculty, Tadulako University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22487/kovalen.2023.v9.i1.16292

Abstract

Corn cobs which generally only become waste can be processed into activated carbon and used for the absorption of heavy metals, such as copper(II) ions. This study aims to determine the morphology of corn cobs charcoal after activation, determine the isothermal adsorption model of copper (II) metal ions on corncob-activated carbon, and then determine the adsorption capacity of copper (II) metal ions on corncob-activated carbon. The morphology of the corncob-activated charcoal obtained was analyzed using Scanning Electron Microscopy (SEM). Isothermal adsorption of copper (II) ions was carried out with various concentrations of copper (II) ions of 5, 10, 20, 50, and 100 ppm. The results of the analysis using SEM showed that the surface shape of the corncob-activated charcoal is regular and has pores with a pore diameter obtained in the range between 1.08-1.26 m and 1.38-1.59 m. The mechanism of adsorption of copper (II) ions by corncob-activated charcoal using KMnO4, following the Freundlich isothermal model with a value of R2 0.9993 with an adsorption capacity of 51 x 10-4 mmol/L. The utilization of activated carbon from corn cobs that are activated by potassium permanganate is very effective for adsorbing copper metal ion pollutants through an adsorption mechanism on the surface of activated carbon.

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