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Sainteknol : Jurnal Sains dan Teknologi
Published by Universitas Negeri Semarang
ISSN : -     EISSN : 25273604     DOI : https://doi.org/10.15294/sainteknol
Core Subject : Education,
Other
Sainteknol published a scientific paper on the results of research and studies in the field of science and technology. Published biannually in June and December contained the writings lifted from the results of research and critical-analysis study in science and technology.
Arjuna Subject : Umum - Umum
Articles 18 Documents
 1   2 
Effervescent Powder Formulation of Ethanol Extract of African Leaves (Vernonia amygdalina) as an α-amylaseInhibitor Norainny Yunitasari; Nasyanka, Anindi Lupita; Luthfi, Sania Al; Ramadhanti, Nadya; Zulfiyana, Lindah Isna
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 1 (2024): June 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i1.2478

Abstract

Vernonia amygdalina or African leaves are reported to have many biological activities, including antidiabetic. However, there are still many people who have not used this plant as an antidiabetic treatment. This research aims to create a medicinal preparation formula in effervescent form with the main ingredient being African leaves. Testing of the dosage formula includes organoleptic tests, water content, pH, and dispersing time. The research results showed that one of the three formulas had better stability after 7 days of storage. After 7 days of storage, the color of the formula became lighter, the pH value changed slightly (7-8), the water content was 2.3% and the dispersion time was 2.00 minutes. This formula can be used as input for further research regarding testing its activity as an antidiabetic through inhibiting alpha-amylase in vitro.
Ultrasound Assisted Ethanolic Extraction of Ipomoea reptans Poir Leaves Antioxidant Activities, Total Phenolic and Flavonoids Arum, Nabila Setri Sekar; Puspitasari, Anita Dwi
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 2 (2024): December 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i2.5331

Abstract

Ipomoea reptans Poir leaves contain phenolic and flavonoid compounds that can reduce free radicals and prevent diseases such as cardiovascular disease, coronary heart disease, and cancer. The drawback of conventional extraction is that it takes a long time, so a shorter extraction method is needed, one of which is the ultrasonic method. This study aims to test the antioxidant activity of ethanol extract of Ipomoea reptans Poir leaves extracted by ultrasonic method and determine the total phenolic and flavonoid content. Ipomoea reptans Poir leaves were extracted using the ultrasonic method at 50oC for 30 minutes with 70% ethanol solvent to obtain ethanol extract of Ipomoea reptans Poir leaves. Antioxidant activity test of ethanol extract of Ipomoea reptans Poir leaves using DPPH method and vitamin C as a comparison. Determination of total phenolic content using gallic acid with a maximum wavelength of 745.20 nm and operating time of 120 minutes. Determination of total flavonoid content using quercetin with a wavelength of 439.60 nm and operating time of 30 minutes. The results showed that the antioxidant activity of Ipomoea reptans Poir leaves obtained an IC50 value of 40.62 ppm (very strong). Total phenolic and flavonoids were 78.33 mgGAE/g extract and 1.03 mgQE/g extract.
Synthesis of Glycerol Monooleate with MgO-Impregnated Natural Zeolite Catalyst Mukti, Nur Indah Fajar; Putri, Avicenna Mustika; Nur, Wahidah; Arobi, Ibnu; Arifa, Muhammad Ridho
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 1 (2024): June 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i1.5441

Abstract

Glycerol Monooleate (GMO) is synthesized via esterification, which involves the reaction between glycerol and oleic acid to yield monoglyceride esters. The esterification reaction is intrinsically slow, requiring the use of a catalyst to decrease the activation energy. The catalyst used in this study is a naturally occurring zeolite catalyst that has been altered through acid treatment and impregnation with Mg(NO3)2, and then subjected to calcination to convert it into MgO. Typically, this research consists of two steps: an initial phase where a natural zeolite catalyst is altered, followed by a subsequent phase where glycerol monooleate production. This study investigates the effects of different variables on the reaction. The variables include temperature (140–180oC), catalyst loading (3-10 %weight), glycerol to oleic acid ratio (2:1, 3:1, 4:1), reaction time (0–180 minutes), and stirring speed (125-525 rpm). The research results demonstrate that the highest conversion rate was achieved with a temperature of 180oC, a catalyst concentration of 10%, and a reactant ratio of 3:1 (glycerol to oleic acid). The ideal response time was found to be 120 minutes. The reaction kinetics can be estimated by employing a pseudo reaction equation that follows a first-order rate law. The rate constant, represented by k', can be approximated using the Arrhenius equation. The reaction has an activation energy of -18.64 kJ.mol-1, and the value of A is 1.41 cm3.g-1.minute-1.
Experimental Investigation on Reduction of High Combined Water Contained Iron Ore by Ammonia-Methane-Mixed Gas Kurniawan, Ade; Iwamoto, Itsuki; Kashiwaya, Yoshiaki; Nomura, Takahiro
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 1 (2024): June 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i1.7215

Abstract

Reducing CO₂ emissions in the steel industry, which contributes 7% of global emissions, is crucial. Ammonia, as a hydrogen-based reducing agent offers one promising solution to address the decarbonization challenge in primary ironmaking process due to its high hydrogen storage density and ease of transport. However, for subsequent steelmaking process, the lack of carbon in the reduced ore from the ammonia-hydrogen iron reduction system must be addressed. In this study, we reduced iron ore using an ammonia-methane mixed reducing gas to introduce carbon into the reduced ore, from the raw material of porous ore prepared from a high combined water, goethite ore. We varied the reduction conditions to investigate how the reaction and carbon content would change, aiming to optimize the reduction process and enhance carbon content in the reduced iron.  The results show that ammonia is primarily consumed for iron reduction, facilitated by hydrogen from its decomposition, while methane decomposes into carbon and hydrogen. Methane decomposition begins around 800°C, significantly increasing the ore's carbon content. Higher temperatures accelerate both reduction and carbon incorporation. The ammonia-methane mixing ratio influences reduction efficiency and carbon content, with a higher ammonia ratio expediting these processes. At 850°C, a 1:1 ammonia-methane mixture yields higher carbon content than higher ammonia ratios. This study highlights the potential of ammonia-methane mixed gases for sustainable steel production by enhancing the reduction and carbonization of high-CW-content iron ores.
Cr(VI) Removal Using A Dual Chamber Microbial Fuel Cell Ferdinand, Julian; Yuniarto, Adhi
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 1 (2024): June 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i1.7752

Abstract

Chromium ions is notably a hazardous heavy metal due to its toxic and carcinogenic nature, particularly in its hexavalent form, Cr(VI). One of the major Cr(VI) pollution source is from electroplating industry effluent, which may contain high concentrations that pose a risk of contamination of aquatic and soil ecosystems if not treated carefully. One of the alternative method known to be able to treat Cr(VI) wastewater is by using microbial fuel cell (MFC). This research focused on on the removal of Cr(VI) from synthetic electroplating wastewater using a 4L dual-chamber MFC under fed-batch condition, as well as investigating the impact of mixed liquor suspended solids (MLSS) and chemical oxygen demand (COD) concentrations to its performance. Observed parameters include the efficiency of Cr(VI) removal and power density. Septage sludge and acetate were both used as biomass and substrate source respectively. Based on this research, it can be concluded that the highest Cr(VI) removal efficiency and power density were achieved using specific MLSS and COD concentration that resulting in F/M ratio of 0,459 to 0,489 gCOD/gMLSS. From initial Cr(VI) concentration of 50 mg/L, the highest removal was obtained by MFC running with initial MLSS and COD concentrations of 3.500 and 1.500 mg/L respectively, achieving 62,17% over 312 hours. This setup also produced the highest power density of 48,22 mW/m².
The Effect of Environmental Conditions on the Alkaloid andFlavonoid Content of Basil Leaves (Ocimum basilicum L)Growing in Kandangan Village Salma, Thania Dita; Na’imah, Janatun; Yunitasari, Norainny
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 2 (2024): December 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i2.10628

Abstract

Basil leaves have long been used as fresh vegetables. Basil leaves are used to eliminate odors and can also be used as antiseptics. Each plant can produce primary and secondary metabolites. The production of these metabolites is influenced by environmental conditions. Kandangan Village is one of the villages in Gresik Regency which has a relatively hot temperature and many industries are located around it. The purpose of this study was to determine the results of phytochemical screening tests for the presence of alkaloid and flavonoid compounds in basil leaves growing in Kandangan Village. This type of research is experimental research. Basil leaf samples were obtained from Kandangan Village. The extraction method used was maceration using 96% ethanol solvent. The test for the presence of alkaloids used the Dragendroff test method and the Mayer test. The test for the presence of flavonoids used the Wilstater test method and the Bate Smite-Metcalfe test. The results of this study indicate that basil leaves growing in Kandangan Village are positive for the presence of flavonoids with a color change to yellow for the Wilstater test and a color change to red in the Bate Smite-Metcalfe test. However, the test for the presence of alkaloids showed negative results because there was no formation of orange to red deposits for the Dragendroff test and yellowish white deposits for the Mayer test.
Optimization of Alkaline Water Production from Rainwater through Electrolysis Method: Effect of Voltage and Time on pH and TDS Rinda Erliana, Savira; Isnina Noor Ubay; Pangestu, Indra Sakti; Atik, Moh. Umar Dani; Wafa, Almas Diqya
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 1 (2024): June 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i1.12507

Abstract

Alkaline water is known to have health benefits due to its higher pH than ordinary water. In this study, the production of alkaline water from rainwater using electrolysis method was optimized, with variations in voltage and time to evaluate its effect on pH and Total Dissolved Solids (TDS). The experiment involved three voltage levels (12 Volt, 24 Volt, and 36 Volt) and three time intervals (10 minutes, 20 minutes, and 30 minutes). The results showed that increasing the voltage and electrolysis time contributed significantly to the increase in water pH, which reached the highest value at 36 Volt for 30 minutes. However, increasing the voltage and time also increased the TDS value linearly, which can affect the water quality if it exceeds a certain limit. This study concludes that the optimal voltage for producing alkaline water with suitable pH and TDS is 24 Volt with an electrolysis time of 20 minutes. Thus, this method offers an efficient and simple solution to produce alkaline water from rainwater, which could potentially benefit public health in areas with limited access to high-quality drinking water.
Optimization Formula of Collagen Nanoemulgel from WasteMilkfish (Chanos chanos) Bones as Antiaging Nasyanka, Anindi Lupita; Tiadeka, pemta; Nur Imtihani, Hilya; Octaviary, Niken Laras; Prastiyo, Danu
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 2 (2024): December 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i2.14768

Abstract

Climate change has negative impacts throughout the countries in the world, especially Indonesia, which has a tropical climate. Successful aging can be achieved by building individual self-confidence through prevention and skin aging. Indonesia is a producer of milkfish waste, reaching 5.4 tons/year, which is in line with the increasing center of "Otak-otak" milkfish souvenirs found in Gresik. The waste, especially fishbones, can be synthesized into collagen. The characteristic fishbone collagen waste are in the form of large porous sheets, while particle size is an essential factor in the absorption effectiveness of cosmetics. Therefore, Nanoemulgel is able to overcome this problem. This research aims to produce best collagen nanoemulgel from milkfish bone by physical evaluation with varying ratios of surfactant: cosurfactant in collagen nanoemulgel. The research method was done experimentally by comparing the components Tween 80: PEG 400 F1 (30:30), F2 (40:20), and F3 (35:15) through qualitative and quantitative physical characteristics using one-way anova. Evaluations whose results differ significantly are pH on the 7th day, spreadability, and viscosity. Research results show F2 is the best formula and meets physical stability specifications : particle size 3.89 nm, PDI 0.1906, zeta potential -0.2 mV, pH 4.7±0.04, viscosity 890.1± 4.26 cps, spreading 5.93±0.23 cm. 
Isolation of Probiotic Lactic Acid Bacteria (LAB) From Commercialized Yogurt Based on 16s rRNA Gene Apriansyah Wibowo; Kaisar Akhmad Khan; Dewi Mustikaningtyas; Rizky Ajie Aprilianto
Sainteknol : Jurnal Sains dan Teknologi Vol. 23 No. 1 (2025): June 2025
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v23i1.19825

Abstract

Yogurt, a globally cherished dairy product, is celebrated not only for its creamy texture and tangy flavour but also for its numerous health benefits, primarily attributed to lactic acid bacteria (LAB). Key LAB species such as Lactobacillus bulgaricus and Streptococcus thermophilus drive the fermentation process, transforming milk into yogurt through lactic acid production. This study aims to isolate and identify LAB species from various yogurt brands using the 16S rRNA gene, employing advanced microbial analysis techniques such as PCR. Yogurt samples from five different brands were collected from a local convenience store in Gunungpati, Central Java, Indonesia. The bacterial inoculation was carried out using MRS agar, and isolated colonies were subjected to direct colony PCR with primers 27f and 1492r. The PCR products were analyzed using agarose gel electrophoresis. The results demonstrated that direct colony PCR is an effective technique for rapidly and accurately detecting bacterial species without the need for DNA extraction. All five yogurt samples contained Lactobacillus sp., as evidenced by the amplification of DNA fragments approximately 1500 base pairs in size. This study confirms the specificity and effectiveness of the 27f/1492r primers in identifying Lactobacillus sp., providing more information for further research on the probiotic roles of LAB in yogurt quality and health impacts.
Effect of Acid-Base Composition on Physical Characteristicsand Antioxidant Activity of “Beras Kencur” EffervescentTablet Astuti, Widi; Putri, Radenrara Dewi Artanti; Sulistyaningsih, Triastuti; Azany, Ghaefira Tasya; Alexandra, Natasya Viona; Saputri, Ria; Jannah, Reni Ainun; Hadikawuryan, Danang Subarkah; Fitri, Zulfa Ajrina
Sainteknol : Jurnal Sains dan Teknologi Vol. 22 No. 2 (2024): December 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/sainteknol.v22i2.20080

Abstract

This study aimed to evaluate the effect of acid-base ratio on the physical characteristics and antioxidant activity of the beras kencur effervescent tablet formulation. The formulation determination was based on the percentage inhibition value, where the highest value (76.2%) was found in beras kencur at 10 mg/mL, so that 1.5 g is needed to achieve the highest potential of radical scavenging activity. In this case, 1.5 g of sample was then incorporated into three effervescent tablets. The acid-to-base ratios used in this study were 1: 1.25 (F1), 1: 1.50 (F2), and 1: 2.50 (F3). The tablets were evaluated for pH, dissolution time, total phenolic content (TPC), and antioxidant activity. The results showed that a higher proportion of base (F3) improved solubility. Meanwhile, antioxidant activity evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) test, and total phenolic content determined using Folin-Ciocalteau, showed that tablets with a higher proportion of acid exhibited higher total phenolic content. However, considering that all three samples have very strong antioxidant activity, it can be concluded that F3 is the optimal formulation.

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