Jurnal Riset Kimia
ISSN / EISSN : 1978-628X / 2476-8960
Published by: Universitas Andalas (10.25077)
Total articles ≅ 232
Latest articles in this journal
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.414
The textile industry including batik has provided broad benefits to society from an economic standpoint. However, there is negative impact from wastewater generated in the production process, which is containing dyes. Various types of dyes are used in the coloring process, and methylene blue is one of most used dye. Various ways have been done to treat wastewater containing methylene blue. Methylene blue processing techniques by adsorption have been carried out with various types of adsorbents. Research on the comparison of the ability of commercial activated charcoal and commercial activated zeolite to adsorb methylene blue was carried out with the addition of an Fe catalyst and a hydrogen peroxide oxidizer. The results showed that the addition of Fe catalyst would increase the degradation of methylene blue in the waste either with activated charcoal or activated zeolite. The combination of using Fe catalyst and hydrogen peroxide oxidizer further increases the removal of methylene blue in both types of adsorbents, activated charcoal and activated zeolite. Activated zeolite has the better ability to adsorb methylene blue than activated charcoal under various conditions.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.417
In this study, the measurement of Cd(II) ion by anodic stripping voltammetry technique was conducted using bentonite modified carbon paste as working electrode (CPE-B). The performance of CPE-B was compared with carbon paste electrode without bentonite (CPE) and applied for determination of Cd(II) concentration in chicory. Optimized parameters were composition of bentonite in carbon paste electrode, deposition time, deposition potential, and scan rate. Validation of measurements was observed including determination of linear concentration range, detection and quantization limits, repeatability of measurement, and percentage of recovery. The optimum composition of bentonite in CPE-B was found at 50%. Furthermore, in the optimization of measurements condition was found the optimum deposition times were 90 and 60 s, deposition potentials were -0.63 and -0.53 V, and scan rates were 15 and 20 mV/s, for CPE and CPE-B. The linear range concentration for CPE observed at 25-2000 µg/L and CPE-B was 5-50 µg/L. Limit of detection and quantization using CPE-B were 0.337 µg/L and 0.349 µg/L, lower than CPE i.e., 0.470 µg/L and 0.471 µg/L, respectively. Repeatability measurement of Cd(II) had Horwitz Ratio value less than two, and percentage of recovery was 96.73 8.33%. The level of Cd(II) ion in chicory was found at 6.98 0.40 mg/kg.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.405
Air bersih yang langka di perumahan Valencia Muaro Jambi yang masih dihadapi masyarakat, oleh sebab itu peneliti bertujuan untuk membantu masyarakat perumahan valensia muaro jambi untuk mendapatkan air bersih menggunakan Lapisan Multi Media-Filter Sabut Pinang (LMM-FSP). LMM-FSP merupakan suatu metoda pengolahan air dengan memanfaatkan tanah sebagai media utama yang dibentuk seperti balok bata dan disusun secara selang-seling diantara zeolit. Sistem LMM-FSP terbuat dari galon bekas dicuci bersih tinggi 40 cm berdiameter 28 cm, berisikan blok bata (12x7x4) cm campuran tanah vulkanik, arang, sabut pinang, serbuk besi (70 :10 :10: 5)%, lapisan permiable digunakan zeolit (1-3 mm). Sampel berasal dari sumur warga perumahan valencia, muaro jambi kota jambi. Penelitian dilakukan dengan variasi massa sabut pinang, laju alir 5, 10, 15, 20 mL/menit dan dua cara yaitu aerasi dan non aerasi, diperoleh efisiensi proses aerasi laju alir 5 ml/menit yang paling baik untuk menurunkan kadar pH; Bau; Nitrit; Nitrat; kekeruhan; Mn; Fe pada aerasi yaitu pH 7,5 ; Tidak Berbau; Nitrit 60,30 %, Nitrat 59,33%, Mn 70,10 %, Fe 73,20% dan pada non aerasi pH 7,3 ; Tidak Berbau, Nitrit 50,82%, Nitrat 48,37% Mn 60,91%, Fe 61,20 % Dari semua nilai efisiensi penurunan parameter sudah bisa dikatakan menuhi untuk syarat air bersih.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.412
Phycocyanin from Spirulina platensis (S. Platensis) is a pigment-complex protein belong to the light-harvesting phycobiliprotein family. The pigments have high economic value as a natural blue dye as well as the source of antioxidants and anticancer. Production of pure natural phycocyanin remains in high demand. Therefore, this study aimed to obtain phycocyanin with high purity values using modified liquid biphasic flotation (LBF) system and tested for DPPH (1,1-diphenyl-2-pycrilhydrazil) radical scavenging activity. This study produced high purity phycocyanin with purification fold 3.041 ± 0.04 and recovery yields approximately about 70.881%. Purified phycocyanin showed scavenging activity with IC50 of 338.585 mg/mL. Thus, the LBF system yielded high purity phycocyanin pigments.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.398
Bioplastics are bio-based plastics from natural resources, made to replace conventional plastics. The utilization of biopolymers in bioplastics provide a faster degradation compared to petroleum-based plastics. Starch-based bioplastic from mixing Durio zibethinus Murr starch and glycerol as plasticizer have been conducted. In this research, the concentration of glycerol has been varied to study the effect on starch-based bioplastics mechanical properties. The tensile strength for Durio zibethinus Murr starch-based bioplastic with 20% glycerol was 50.28 MPa with 13.3% elongation. The functional group found on the Fourier transform infrared spectroscopy (FTIR) spectra indicated the presence of O-H stretch, C-H stretch, C=O stretch, and C-O stretch which stated the formation of bioplastic. The image results gained from scanning electron microscope (SEM) showed that the morphology surface of bioplastic was less homogenous and rough. The soil burial test for biodegradability showed Durio zibethinus Murr starch-based bioplastic achieved 38.9% weight loss in a 5-day observation.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.406
Fingerprint is a technology that can be used to identify a person. The dusting method is most often used on latent fingerprints because it is relatively easy and simple. However, the composition of the ingredients used in latent fingerprint powder is toxic and can be hazardous to health. This research was carried out using a new natural powder from Suji leaf as a simple, non-toxic, and cheaper. Suji leaf powder produces a green color that comes from the chlorophyll compounds contained in it. This chlorophyll compound will bind to alanine to identify latent fingerprints. The particle sizes used in this study were of 60-200 mesh. The results found that the particle sizes of 100 and 200 mesh provided good green contrast and clear visualization of the fingerprint patterns. Meanwhile, at the particle size of 60 and 80 mesh, it was found that the results were not clear visualized. The highest percentage of fingerprint patterns based on blood group, gender and ethnicity was found in form of loops. The percentage of fingerprint patterns formed based on the highest was of O 31.1; B 12.2; AB 8.8; and A 6.6 percent. The highest percentage of fingerprint patterns formed by gender were of 45.5 for women and 13.3 percent for men. The highest percentage of fingerprint patterns formed by ethnicity were Malay 21.1, Batak 20, and Javanese 17.7 percent.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.383
The aim of this study is to investigate antioxidant activity and total phenolic content of ethyl acetate fraction of Sembung leaves. Sembung (Blumea balsamifera L.) is a plant that has the potential as an antioxidant because it contains secondary metabolites of alkaloids, steroids, flavonoids, saponins, and phenolic compounds. In this study, antioxidant activity was tested by using 1,1-diphenyl-2-picrylhydrazyl (DPPH) for free radical scavenging activity assay. Evaluation of total phenolic content was tested by using the Folin-Ciocalteau method. The results showed that the ethyl acetate fraction of Sembung leaves possess showed medium antioxidant activity with IC50 valueof 221.821 compare with reference standard ascorbic acid with IC50 value 68.25 ppm. The ethyl acetate fraction of Sembung leaves has a total phenolic content of 161.101 mg GAE/g. This study provided that Blumea balsamifera leaves possess antioxidant.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.388
The ability of the tropical white-rot fungi and their enzyme to decolorize synthetic dyes was investigated. Production of lignin-modifying enzymes (LMEs) from the three new isolated fungi, namely Trametes hirsuta D7, Ceriporia sp. BIOM 3, and Cymatoderma dendriticum WM01 were observed for 9 days incubation under static condition. The results showed that the LMEs production enhanced in the present of guaiacol. T. hirsuta D7 produced only laccase (Lac), with the highest activity was 22.6 U/L on the 5th-day of the cultivation. At the same time, Ceriporia sp. BIOM 3 and C. dendriticum WM01 secreted both laccases (Lac) with the activities 0.2 U/L and 1.0 U/L, respectively, and manganese peroxidase (MnP) with the activities 0.1 U/L and 1.0 U/L, respectively. Among the fungi, T. hirsuta D7 efficiently degraded 65% Remazol Brilliant Blue–R (RBBR) dye within 72 h using the only laccase. This study shows that laccase may have a major role in synthetic dyes' decolorization process, followed by MnP and LiP.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.404
Pacar air (Impatiens balsamina L.) plant belongs to the Balsaminaceae family and is used as an indigenous medicine in Asia for fingernail inflammation, fractures, and rheumatism treatments. Moreover, the antipruritic, antianaphylactic, antifungal, antibacterial, and antitumor activities of some compounds, especially phenolics and quinones from this plant have been studied extensively. Therefore, this study aims to determine the antifungal activity of Pacar air leaves (Impatiens balsamina L.) methanol extract against Rhizopus oryzae L. and the IC50 value. The results showed that an increase in the concentrations of I. balsamina L. leaves methanol extract significantly raised the fungal growth. Furthermore, the extract inhibition against R. oryzae L. at various concentrations of 0.5; 0.7; 0.9; 1.1; and 1.3% w/v were 10, 21.9, 58.06, 68.06, and 79.72%, respectively, while the IC50 value was 0.896%. Hence, the presence of naphthoquinones and other secondary metabolites are responsible for its antifungal activity. Based on these results, the antifungal potential of I. balsamina L. leaves against soft-rot fungi is useful in the future.
Jurnal Riset Kimia, Volume 12; https://doi.org/10.25077/jrk.v12i2.408
Modified chitosan membrane is one of the promising membranes for polymer electrolyte membrane. Chitosan/N-phthaloyl chitosan composite membranes were fabricated to obtain high proton conductivity and low methanol permeability. Membranes were fabricated by casting method and solvent evaporation. Surface morphology, mechanical analysis, methanol permeability, and proton conductivity were used to characterize the overall properties. FT-IR spectra exhibited the presence of interaction of chitosan and n-phthaloyl/chitosan. SEM analysis showed that the surface roughness of composite membrane increases as the n-phthaloyl loading increases. The highest proton conductivity of synthesized membrane is at 2.4 mS.cm-1 and is higher than pristine chitosan membrane at 1.6 mS.cm-1. Moreover, with n-phthaloyl/chitosan addition, the methanol permeability was also improved. The correlation between proton conductivity and methanol permeability in composite membranes suggests that the blend has its potential in DMFC application.