Authors:Rika Eka Afrellia, Anita Dwi Puspitasari Pages: 43 - 51 Abstract: Carrot (Daucus carota L.) contains phenolic and flavonoid compounds that contribute to various pharmacological activities. Phenolic and flavonoids can be extracted using various solvents. Solvent polarity difference will produce amounts and types of secondary metabolites differently. This research aims to compare the total phenolic and flavonoid content of carrot extract from various solvents. Carrot was extracted using the maceration method with n-hexane, ethyl acetate, and 70% ethanol as solvent to obtain n-hexane, ethyl acetate, and 70% ethanol extract of carrot. Spectrophotometry carried out the determination of total phenolic content by comparing gallic acid and total flavonoids with a comparison of quercetin. The maximum wavelength of gallic acid is 739.60 nm and the operating time of 120 minutes. The maximum wavelength of quercetin is 427.50 nm and an operating time of 30 minutes. Total phenolic and flavonoid levels of carrot extract from the three solvents were analyzed statistically through one-way ANOVA followed by the Bonferroni test at a 95% confidence level. The results showed that the total phenolic contents of the n-hexane extract, ethyl acetate, and 70% ethanol extract of carrot 11.881±0.31; 24.308±1.33 and 39.398±1.65 mg GAE/g extract. The flavonoid content was 2.650±0.13; 20.675±2.58 and 9.063±0.99 mg QE/g extract respectively. The highest total phenolic content was obtained from 70% ethanol solvent and the highest total flavonoid was obtained from ethyl acetate solvent. PubDate: 2023-12-08 DOI: 10.15294/sainteknol.v21i2.47248 Issue No:Vol. 21, No. 2 (2023)
Authors:Reviana Inda Dwi Suyatmo, Abdussalam Topandi, Indah Gita Cahyani Gultom, Lukman Nulhakim Pages: 52 - 59 Abstract: Self-healing coating is a technology where repairation of a coating can be done automatically. The self-healing agent is encapsulated in the form of microcapsules. When the microcapsules or shell material breaks, the healing agent released onto the damaged surface. In this study, walnut oil was used as a healing agent because it belongs to the drying oil which has been widely used as a coating. The polymer used as the microcapsule shell is urea-formaldehyde. This research was conducted to examine the effect of mixing speed on the diameter and thermal stability of microcapsules encapsulated by walnut oil in urea formaldehyde, as well as to see the self-healing performance. The results of FTIR testing proved that the microcapsules consist of Poly Urea Formaldehyde (PUF) as a shell material. The research showed that the mixing speed of 860 rpm produced microcapsules with the smallest diameter of 90.1426 micrometer and the highest decomposition temperature of 362.38°C. The results of self-healing tests on steel plates prove that the healing agent used has succeeded in repairing the damage by covering the surface of the scratched sample. PubDate: 2023-12-08 DOI: 10.15294/sainteknol.v21i2.48141 Issue No:Vol. 21, No. 2 (2023)
Authors:Muhamad Zakky Irsyada, Hasna Amalia Fauziyyah, Ayuk Permata Sari Pages: 60 - 69 Abstract: The process of dyeing batik fabric is a significant source of water pollution due to synthetic dyes. Only 5% of this compound is used, while 95% will be disposed of as waste. This compound is relatively stable, so it is tough to degrade in nature and is dangerous for the environment because it can cause effects such as increasing COD (Chemical Oxygen Demand) and BOD (Biological Oxygen Demand). Constructed wetlands in sub-surface flow type is a wastewater treatment method that utilizes the role of plants and microorganisms found in the plant root area or rhizosphere. Nutgrass (Cyperus Rotundus L.) is rarely used and is considered a weed that causes harm to surrounding plants. On the other hand, nutgrass is a plant with good remediation and straightforward maintenance. In this research, the nutgrass plant was used as a phytoremediator with planting media in the form of sand and gravel to improve the performance of constructed wetlands in processing liquid batik waste. Based on the analysis of BOD and COD test parameters, the results showed that nutgrass could reduce BOD levels by up to 75% and COD levels by 73% so that wastewater produced from artificial wetlands flows more safely and can be used for irrigation and plants sanitation. PubDate: 2023-12-11 DOI: 10.15294/sainteknol.v21i2.49818 Issue No:Vol. 21, No. 2 (2023)
Authors:Maulana Dzaki Munawar, Moh Luqman Hakim, Ade Mundari Wijaya, Dwi Novriadi Pages: 70 - 80 Abstract: The syntactic foam composite possesses both light and strong qualities. Syntactic foam composite is commonly employed as a buoyant lighting material in amphibious aircraft due to its excellent foaming capability. Composite syntactic foam is utilized because of its ability to efficiently support material drying while maintaining excellent structural strength (mechanical characteristics). In order to ascertain the syntactic compound density, one can determine the composite density based on the ASTM D790 standard. This involves evaluating the porosity calculation and doing a literature review to establish the characteristics of the void. The density of a syntactic foam composite is determined by the density of the filling matrix (microballoon k15), the percentage of porosity, and the identification of voids. The use of the K15 microballoon material will reduce the overall density of the composite because of its substantial structure. The number of small cavities within the composite syntactic foam is indicated by the porosity ratio.Nevertheless, not all apertures present in syntactic foam composites can be classified as k15 microballoon structures, as the composite manufacturing process may result in the formation of air bubbles that become trapped within the composite. The function has no return value. The excessive presence of voids can significantly reduce the density and mechanical strength, leading to a drop in the overall quality of the syntactic foam composite. Porosity analysis is crucial for assessing the quality of drying in syntactic foam composites. The study involved assessing the composite density of syntactic foam with varying concentrations of 0-50% w/w of the k15 microballoon material, following the ASTM D790 standard. The porosity value of the foam was subsequently determined and studied. The findings of this study can serve as a robust point of reference for analyzing the correlation between the density of the reference material and the composite syntactical foam's relative density in different variations. PubDate: 2023-12-11 DOI: 10.15294/sainteknol.v21i2.49530 Issue No:Vol. 21, No. 2 (2023)
Authors:Hanif Ardhiansyah, Radenrara Dewi Artanti Putri, Maharani Kusumaningrum, Faizal Reza Amirruddin Akbar, Daffa Bimo Fidiano Pages: 81 - 88 Abstract: Rice husk is a type of lignocellulosic biomass that can be chosen as a raw material for bioethanol production because it is abundant, cheap, and renewable. However, when it comes to lignocellulosic biomass, the main obstacle in using rice husks is the pretreatment process to remove the lignin content and prepare the lignocellulose so that it can be easily hydrolyzed. In this study, two combinations of pretreatment were used, namely microwave pretreatment and ultrasonic pretreatment, which used several variables. Microwave pretreatment uses variable time (2.5 minutes, 5 minutes, and 7.5 minutes) and power (100, 180 and 300 watts) as well as ultrasonic pretreatment uses variable time (20 minutes, 25 minutes, and 30 minutes) and power (70, 80 and 90 watts). The pretreatment results were hydrolyzed with sulfuric acid and fermented using saccharomyces cerevisiae yeast at varying times (3, 6, 9, 12, and 15 days). This research shows that microwave pretreatment is the most effective in reducing lignin. The lowest lignin content was 10.58% after 5 minutes and 180 watts of power. Bioethanol levels increased until the 15th day of fermentation, with the highest yield of 16%. PubDate: 2023-12-20 DOI: 10.15294/sainteknol.v21i2.50272 Issue No:Vol. 21, No. 2 (2023)
Open Access journal
