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Study of The Correlation Between Contact Angle Values with The Polarity of Liquids Syahara, Muhammad Alwi; Kurniawan, Fredy; Anggriawan, Wahyu
IPTEK Journal of Proceedings Series No 1 (2015): 1st International Seminar on Science and Technology (ISST) 2015
Publisher : Institut Teknologi Sepuluh Nopember

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (186.763 KB) | DOI: 10.12962/j23546026.y2015i1.1176

Abstract

Contact angle measurement is a technique which can be used to determine the surface properties of a substance and observe the interaction of surfaces. When polar liquid dropped on a non-polar solid, it will make an interaction that can observed from the contact angle. In simple way, the different polarity of the solid and the liquid sample will affect to the contact angle obtained. In this work the value of contact angle will be correlated to the polarity of the sample. The results showed that the plot between polarity parameter with contact angle on polytetrafluoroethylene substrat has a correlation which formed a sigmoidal curve with R2=0,954. It means the polarity of liquids can be determined by the contact angle values.
Study of Essential Oil Extraction of Rosella Flower Petals (Hibiscus Sabdaíiffa L.) Water Steam Destilation Method Nunuk Helilusiatiningsih; Titik Irawati; Muhammad Alwi Syahara
International Journal of Advanced Technology and Social Sciences Vol. 1 No. 1 (2023): September 2023
Publisher : MultiTech Publisher

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.59890/ijatss.v1i1.402

Abstract

Indonesia had a tropical climate, rosella can grow abundantly. The problem that exists is how to extract essential oils from these plants and screen for phytochemicals in plant organs. The aim of the research was to study the extraction of essential oils from rosella flower petals and phytochemical screening, sensory testing of the oil results. The research method is essential oil extraction using water steam distillation, color and aroma analysis using the hedonic method and the DPPH test. The research results are as follows. The yield of essential oils in flower petals is 0.0136% in 1.1 kg of dry material. The color test was 60% very like it, 40% liked it and the aroma test for essential oils was around 55%, they really liked it and 45% liked it, while the panelists didn't like it 0%. Results of analysis of the antioxidant activity of rosella flower petal extract with a concentration of 5 ppm = 30.6%; 10 ppm = 33.7 %; 25 ppm = 41.7 %; 50 ppm = 45 %; 100 ppm = 48.3%; 200 ppm = 57.5 %.
Characterization and Antioxidant Activity Assay of Essential Oil Parts of Rosella (Hibiscus sabdariffa L.) Nunuk Helilusiatiningsih; Muhammad Alwi Syahara; Titik Irawati
Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) Vol 13, No 3 (2024): September 2024
Publisher : The University of Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtep-l.v13i3.671-678

Abstract

Rosella (Hibiscus sabdariffa L.) is known as a plant whose calyx contain high levels of antioxidant bioactive compounds and good inhibitory power against free radicals. However, other parts of the rosella plant have not yet been utilized for their antioxidant content and activity. The aim of this research is to compare the profiles of essential oils of parts of the rosella plant (seeds, leaves and flower petals) and their antioxidant activity. This research method begins with the process of extracting essential oils using the water-steam distillation method. Furthermore, the profile of the essential oil is known from the results of yield calculations and characterization using the GC-MS instrument. The antioxidant activity was tested using the DPPH method. The yield of essential oils obtained was 0.0107% for seeds, 0.0087% for leaves and 0.0136% for flower petals. GC-MS characterization shows that the most abundant chemical components contained in the essential oils of seeds, leaves, and flower petals are fatty acid compounds (2-propanoic acid, butanoic acid, hexanoic acid) and esters (neopentyl isobutyrate). The results of the antioxidant activity test showed the IC50 value for each essential oil, namely, seeds: 30.15 μg/ml, leaves: 171.27 μg/ml and flower petals: 126.58 μg/ml. The compound characteristics obtained showed the best results for rosella seed essential oil, this was supported by the fairly high antioxidant activity test results IC50 <50 μg/ml. Keywords: Antioxidant activity, Characterization, Essential oils, IC50, Yield.
EKSTRAKSI MINYAK ATSIRI DAUN ROSELLA (Hibiscus Sabdaíiffa L ) METODE WATER STEAM DESTILATION Helilusiatiningsih, Nunuk; Irawati, Titik; Syahara, Muhammad Alwi
BUANA SAINS Vol 23, No 3 (2023)
Publisher : Universitas Tribhuwana Tunggadewi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.33366/bs.v23i3.5647

Abstract

The rosella plant has antioxidant and coloring compounds that are useful for coloring and aromatic various drinks. The research aimed to study the extraction of essential oils from rosella leaves through phytochemical screening and sensory testing of the oil results. The research method used extraction of essential oil using water steam distillation, color, aroma analysis using the hedonic method, and antioxidant activity using the DPPH method. Results showed the amount of essential oils in leaves is 0.0087% in 1 kg of dry material. Rosella Leaf Oil 25% like the yellow color, 75% like it, 0% dislike it, 30% like the aroma of the leaf essential oil, 70% like it, and 0% dislike it. The antioxidant activity in rosella leaves with concentrations (ppm): of 5, 10, 25, 50, 100, and 200 ppm (22,5; 29,7;  34,9;  42,13;  44,5;  51, 4)%.  A comparison or control test using ascorbic acid with the same concentration as above showed a percentage of inhibition (37,53;44,16; 51,84; 61,19; 72,45; 88,22)%.  The IC 50 value of ascorbic acid (as a control) is 26.94 ppm and the IC 50 of Rosella leaf extract is 171.27 ppm, which is classified as having weak antioxidant activity in the leaves. The GC-MS results showed essential oil consists cis-3 Hexenyl Acetate (11.50%), 3-Cyclohexene-1-methanol (4.97%), 2-Propenoic acid (2.65%), Linalool 3,7-oxide (2.15%), Methyl 4-methylhexanoate (1,54%), Butanoic acid (0.54 %), 3-Methylpent-3-en-2-ol (0.25%), 1-Hexen-3-ol (0,24%).
Application of POC fertilization from organic waste and humic acid on the growth and production of sweet corn (Zea mays L. Saccharata sturt) Helilusiatiningsih, Nunuk; Syahara, Muhammad Alwi

Publisher : Fakultas Pertanian Universitas Yudharta Pasuruan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35891/agx.v15i2.4434

Abstract

Introduction: Sweet corn in Indonesia was the main commodity after rice, and it was useful for food, the snack processing industry, semi-finished ingredients, side dishes, and animal feed. Problems with sweet corn farming include limited land, inappropriate cultivation technology, expensive superior seeds, insufficient water availability, fertilizers and pesticides that do not meet needs, as well as expensive and difficult labor, and competition with other commodities. The quality of the corn was that the husk was bright green and slightly moist, the sweet corn tassels were light brown and moist, and the grain texture was dense. The research aimed to analyze the effect of adding humic acid and POC on the growth and yield of sweet corn. Methods: The experimental design was RAKF. The first factor was humic acid (A) consisting of 4 levels: control, 5 kg/ha, 10 kg/ha, and 15 kg/ha. The second factor is POC (P) consisting of 5 levels: control, 60 ml/l, 90 ml/l, 120 ml/l, and 150 ml/l so there are 20 experimental combinations. Analysis used the F count test, 5% BNT test, and 5% DMRT test. Results: In the analysis of plant height, number of leaves, and weight of corn with and without husks, the best combination was A3P4.The P4 level (150 ml/L) has the highest level of sweetness but is not significantly different, the degree of sweetness was 16.25 brix. Addition of humic acid at a concentration of 15 kg/Ha. Produces a sweetness degree of 18.35 brix. Conclusion: The results of the study indicated a significant influence from the combination of treatments, as well as an interaction between the experimental treatments. The most effective combination was A3P4, which involved a humic acid concentration of 15 kg/ha and a POC dose of 150 ml/L. This combination yielded the best results for the tested parameters and sweetness levels.
Spektrofotometer Portable Untuk Larutan Berbasis Android App Dimas Dwi Jati; Danang Erwanto; Muhammad Alwi Syahara
Jurnal JE-UNISLA : Electronic Control, Telecomunication, Computer Information and Power System Vol 10 No 2 (2025): SEPTEMBER
Publisher : Universitas Islam Lamongan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30736/je-unisla.v10i2.1545

Abstract

Pengembangan spektrofotometer portabel berbasis aplikasi Android menjadi penting untuk pengukuran larutan secara praktis dan efisien di lapangan. Penelitian ini bertujuan merancang dan menguji spektrofotometer portabel menggunakan sensor cahaya AS7341 dan mikrokontroler ESP8266 yang terhubung ke aplikasi Android untuk pencatatan data absorbansi secara real time. Perangkat berukuran kecil (18,5 × 9,5 × 5 cm) ini diuji performanya dengan larutan CuSO₄ melalui pengukuran triplo pada berbagai konsentrasi. Hasil menunjukkan hubungan linier antara absorbansi dan konsentrasi dengan koefisien determinasi (R²) 0,9 serta akurasi baik pada konsentrasi ≥15 ppm dibanding spektrofotometer UV-Vis. Portabilitas dan efisiensi biaya menjadikan alat ini potensial sebagai alternatif analisis sederhana di luar laboratorium.
Application of POC fertilization from organic waste and humic acid on the growth and production of sweet corn (Zea mays L. Saccharata sturt) Helilusiatiningsih, Nunuk; Syahara, Muhammad Alwi
AGROMIX Vol 15 No 2 (2024)
Publisher : Fakultas Pertanian Universitas Yudharta Pasuruan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35891/agx.v15i2.4434

Abstract

Introduction: Sweet corn in Indonesia was the main commodity after rice, and it was useful for food, the snack processing industry, semi-finished ingredients, side dishes, and animal feed. Problems with sweet corn farming include limited land, inappropriate cultivation technology, expensive superior seeds, insufficient water availability, fertilizers and pesticides that do not meet needs, as well as expensive and difficult labor, and competition with other commodities. The quality of the corn was that the husk was bright green and slightly moist, the sweet corn tassels were light brown and moist, and the grain texture was dense. The research aimed to analyze the effect of adding humic acid and POC on the growth and yield of sweet corn. Methods: The experimental design was RAKF. The first factor was humic acid (A) consisting of 4 levels: control, 5 kg/ha, 10 kg/ha, and 15 kg/ha. The second factor is POC (P) consisting of 5 levels: control, 60 ml/l, 90 ml/l, 120 ml/l, and 150 ml/l so there are 20 experimental combinations. Analysis used the F count test, 5% BNT test, and 5% DMRT test. Results: In the analysis of plant height, number of leaves, and weight of corn with and without husks, the best combination was A3P4.The P4 level (150 ml/L) has the highest level of sweetness but is not significantly different, the degree of sweetness was 16.25 brix. Addition of humic acid at a concentration of 15 kg/Ha. Produces a sweetness degree of 18.35 brix. Conclusion: The results of the study indicated a significant influence from the combination of treatments, as well as an interaction between the experimental treatments. The most effective combination was A3P4, which involved a humic acid concentration of 15 kg/ha and a POC dose of 150 ml/L. This combination yielded the best results for the tested parameters and sweetness levels.
Characterization and Antioxidant Activity Assay of Essential Oil Parts of Rosella (Hibiscus sabdariffa L.) Helilusiatiningsih, Nunuk; Syahara, Muhammad Alwi; Irawati, Titik
Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) Vol. 13 No. 3 (2024): September 2024
Publisher : The University of Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jtep-l.v13i3.671-678

Abstract

Rosella (Hibiscus sabdariffa L.) is known as a plant whose calyx contain high levels of antioxidant bioactive compounds and good inhibitory power against free radicals. However, other parts of the rosella plant have not yet been utilized for their antioxidant content and activity. The aim of this research is to compare the profiles of essential oils of parts of the rosella plant (seeds, leaves and flower petals) and their antioxidant activity. This research method begins with the process of extracting essential oils using the water-steam distillation method. Furthermore, the profile of the essential oil is known from the results of yield calculations and characterization using the GC-MS instrument. The antioxidant activity was tested using the DPPH method. The yield of essential oils obtained was 0.0107% for seeds, 0.0087% for leaves and 0.0136% for flower petals. GC-MS characterization shows that the most abundant chemical components contained in the essential oils of seeds, leaves, and flower petals are fatty acid compounds (2-propanoic acid, butanoic acid, hexanoic acid) and esters (neopentyl isobutyrate). The results of the antioxidant activity test showed the IC50 value for each essential oil, namely, seeds: 30.15 μg/ml, leaves: 171.27 μg/ml and flower petals: 126.58 μg/ml. The compound characteristics obtained showed the best results for rosella seed essential oil, this was supported by the fairly high antioxidant activity test results IC50 <50 μg/ml. Keywords: Antioxidant activity, Characterization, Essential oils, IC50, Yield.
Antioxidant activity assay of Roselle (Hibiscus sabdariffa) seeds Ethanol extract with DPPH radical scavenging using UV-Vis Spectrophotometer Syahara, Muhammad Alwi; Helilusiatiningsih, Nunuk; Irawati, Titik
Journal of Natural Sciences and Mathematics Research Vol. 10 No. 1 (2024): June
Publisher : Faculty of Science and Technology, Universitas Islam Negeri Walisongo Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Hibiscus sabdariffa (Roselle) is known to have a strong antioxidant compound. Thus, the calyx becomes the most important area to research. Another part of this plant that was starting to be known for its benefits is rosella seeds. Roselle seeds are a source of fat-soluble antioxidants. The aim of this study was to investigate the antioxidant activity of Roselle Seed Ethanol Extract (RSEE) with the DPPH (1,1-Diphenyl-2 Picrylhidrazyl) radical scavenging method. This research begins by doing the extraction of Roselle seeds using ethanol (96%) as a solvent and then assessing the antioxidant activity (Radical Scavenging Activity/RSA) of the extract, which is compared with the ascorbic acid standard at several concentrations (5-200 ppm). Antioxidant activity was assessed with DPPH Radical Scavenging using UV-Vis spectrophotometer and IC50 value parameters. The results of this study were the absorbance of DPPH from spectrophotometer at 517 nm was 0,824 (purple color). The absorbance of RSEE and ascorbic acid at 5 ppm to 200 ppm, respectively 0.523-0.124 and 0.594-0.112. The antioxidant activity (RSA) of the RSEE and ascorbic acid, respectively was  57.93% and 59.24%. The IC50 value of RSEE was 30.158 μg/ml and as comparison is ascorbic acid, the IC50 value was 26.948 μg/ml. Thus, the antioxidant activity of roselle seeds ethanol extract (RSEE) belongs to a very strong category (<50 μg /ml). This is due to the presence of several phenolic compounds and unsaturated fatty acid derivatives.