 Subjects -> SCIENCES: COMPREHENSIVE WORKS (Total: 374 journals)
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- Larvicidal Activity of Streptomyces sp. Liquid Cultures Against Aedes
aegypti Larvae
Authors: Ni Wayan Desi Bintari, Putu Ayu Parwati
Pages: 1 - 12
Abstract: : The tropics have significant future challenges in controlling the vectors of dengue hemorrhagic fever. The occurrence of resistance to chemical control encourages the development of strategies based on biological control. This study aimed to test the larvicidal activity of Streptomyces sp. liquid culture toward A. aegypti larvae. The selection of Streptomyces as a bio-larvicide was carried out by a chitinase test. Chitinase-producing bacteria were cultivated in biomass culture. The study was conducted using a completely randomized design. The results of this study can be isolated 4 Streptomyces isolates from muddy soil. Among the isolates, Streptomyces sp.4 showed chitinolytic activity on in vitro tests; therefore, it was used for larvicidal activity. Based on the Duncan test result, Streptomyces sp.4 culture showed a significant effect on larval mortality compared to the negative control (p<0.05). The highest rate of larval mortality was found in the A6B1 treatment (34.35%). The results of the Probit test showed that the LD50 value of the Streptomyces sp.4 culture was 24.6±5.4 mL. Based on the in vivo test, showed that Streptomyces sp.4 liquid culture affected the mortality rate of A. aegypti larvae and was significantly different from the negative control (p<0.05). Streptomyces sp.4 is known to have potential benefits as a biological larvicidal agent.Abstrak: Daerah tropis memiliki tantangan besar kedepannya dalam pengendalian vektor demam berdarah dengue (DBD). Adanya kejadian resistensi pengendalian dengan zat kimiawi mendorong strategi pengembangan berbasis pengendalian biologis. Penelitian ini bertujuan untuk melakukan pengujian aktivitas kultur Streptomyces sp. sebagai larvasida A. aegypti. Seleksi Streptomyces sebagai biolarvasida dilakukan dengan uji aktivitas kitinase. Bakteri penghasil kitinase dilakukan kultivasi kultur biomassa untuk pengujian in vivo. Rancangan uji menggunakan Rancangan Acak Lengkap. Hasil penelitian dapat diisolasi 4 isolat Streptomyces yang diisolasi dari tanah berlumpur. Diantara keempat isolat, satu isolat yaitu Streptomyces sp.4 menunjukkan aktivitas kitinolitik sehingga digunakan untuk uji aktivitas larvasida secara in vivo. Hasil uji larvasida menunjukkan perlakuan kultur Streptomyces sp.4 berpengaruh nyata terhadap persentase kematian larva dibandingkan kontrol negatif (p<0.05) berdasarkan hasil uji Duncan. Persentase kematian tertinggi didapatkan pada perlakuan A6B1 yaitu sebesar 34.35%. Hasil uji Probit menunjukkan nilai LD50 dari kultur Streptomyces sp.4 adalah 24.6 ± 5.4 mL. Berdasarkan hasil uji in vivo diketahui bahwa perlakuan kultur cair Streptomyces sp.4 berpengaruh terhadap tingkat kematian larva A. aegypti dan berbeda nyata dengan kontrol negative (p<0.05). Streptomyces sp. 4 diketahui memiliki potensi sebagai salah satu agen larvasida biologis.
PubDate: 2023-01-18
DOI: 10.22373/ekw.v8i2.11436
Issue No: Vol. 8, No. 2 (2023)
- Hydrodeoxygenation of Castor Oil As an Alternative Source of
Biohydrocarbon Using Nickel Catalyst Loaded On Hzsm-5 Zeolite
Authors: Muhammad Abimansyah Saragih, Muhammad Irvan Hasibuan, Loren Simangunsong, Ahmad Nasir Pulungan, Junifa Layla Sihombing
Pages: 13 - 25
Abstract: : The need for energy continues to increase along with rapid population growth. Fuel is one of the most critical energy sectors. However, the limited availability of fossil fuels and the issue of air pollution have prompted various studies to find alternative fuels that are renewable and environmentally friendly. In this study, the conversion of castor oil into biohydrocarbons through the hydrodeoxygenation (HDO) process using the HZSM-5 catalyst loaded with Ni (Ni/HZSM-5) aims to produce biohydrocarbon products as a component of liquid fuel. This research has been carried out in 3 main stages, including: 1) Catalyst preparation; 2) Catalyst characterization; and 3) Activity and selectivity test of HZSM-5 catalyst and Ni/HZSM-5 in the hydrodeoxygenation process of castor oil at reaction temperatures of 350 oC, 375 oC, and 400 oC. The conversion results of castor oil using HZSM-5 and Ni/HZSM-5 catalysts were 3.23%, 25.65%, 43.72%, and 13.78%, 35.03%, 71.01%, respectively. From the GC-MS analysis data on the product at 400 oC, the selectivity of HZSM-5 and Ni/HZSM-5 was 20.02% and 23.71% for the kerosene fraction, as well as 15.79% and 11.01% for the gasoil fraction, respectively.Abstrak: Kebutuhan energi terus meningkat seiring dengan pertumbuhan jumlah penduduk yang sangat pesat. Salah satu sektor energi yang paling dibutuhkan adalah bahan bakar minyak. Namun kesediaan bahan bakar fosil yang terbatas dan isu pencemaran polusi udara, mendorong berbagai penelitian untuk menemukan alternatif bahan bakar yang terbarukan dan ramah lingkungan. Dalam penelitian ini, konversi minyak jarak menjadi biohidrokarbon melalui proses hidrodeoksigenasi (HDO) menggunakan katalis HZSM-5 teremban logam Ni (Ni/HZSM-5) bertujuan untuk menghasilkan produk biohidrokarbon sebagai komponen bahan bakar cair. Penelitian ini telah dilakukan dengan 3 tahapan utama yaitu 1) Preparasi katalis, 2) Karakterisasi katalis, 3) Uji aktivitas dan selektifitas katalis HZSM-5 serta Ni/HZSM-5 dalam proses hidrodeoksigenasi minyak biji jarak dengan temperatur proses 350 oC, 375 oC, dan 400 oC. Hasil konversi minyak biji jarak dengan menggunakan katalis HZSM-5 dan katalis Ni/HZSM-5 berturut-turut sebesar 3.23%, 25.65%, 43.72% dan 13.78%, 35.03%, 71.01%. Dari data analisis GC-MS produk di suhu 400 oC diperoleh selektivitas katalis HZSM-5 dan katalis Ni/HZSM-5 berturut-turut adalah 20.02% dan 23.71% untuk fraksi kerosene, serta 15.79% dan 11.01% untuk fraksi gasoil.
PubDate: 2023-01-18
DOI: 10.22373/ekw.v8i2.12583
Issue No: Vol. 8, No. 2 (2023)
- Identification of Power Quality Disturbances Using S-Transform and
Multi-Class Support Vector Machine
Authors: Alex Wenda
Pages: 26 - 41
Abstract: : An essential issue in power quality disturbances is identifying and classifying power quality disturbances from anywhere and at any time. This article proposed a new approach to identify and classify power quality disturbances over the web using S-transform, Multi-Class Support vector machine (SVM), and Matlab framework. S-Transform is used as an extraction feature to obtain the temporal frequency characteristics of power quality events. The development of the multi-class SVM classifier, in which the system classifies various power quality disturbances. Finally, the Matlab framework integrated the graphical and computational processes with remote access via the web. The test result indicated the suggested method's effectiveness and robustness for identifying and classifying power quality disturbances through the web.Abstrak: Masalah penting dalam gangguan kualitas daya adalah mengidentifikasi dan mengklasifikasikan gangguan kualitas daya dari mana saja dan kapan saja. Artikel ini mengusulkan pendekatan baru untuk mengidentifikasi dan mengklasifikasikan gangguan kualitas daya melalui web menggunakan S-transform, Multi-Class Support vector machine (SVM), dan Matlab. S-Transform digunakan sebagai fitur ekstraksi untuk mendapatkan karakteristik frekuensi temporal dari peristiwa kualitas daya. Multi class SVM classifier dikembangkan dimana sistem mengklasifikasikan berbagai gangguan kualitas daya. Akhirnya, Matlab framework mengintegrasikan proses grafis dan komputasi sehingga dapat diakses jarak jauh melalui web. Hasil pengujian menunjukkan efektivitas dan robustnes metode yang usulkan untuk mengidentifikasi dan mengklasifikasikan gangguan kualitas daya melalui web.
PubDate: 2022-12-31
DOI: 10.22373/ekw.v8i2.13026
Issue No: Vol. 8, No. 2 (2022)
- Synthesis of Silica-PEG By Physically Coating With PEG 4000 For Absorption
of Ion Nitrate
Authors: Aster Rahayu, Maryudi Maryudi, Joni Aldilla Fajri, Lee Wah Lim, Nuraini Nuraini
Pages: 42 - 53
Abstract: : All production activities will eventually produce waste, especially liquid waste. The nitrate ion (NO3-) is one of the substances in liquid waste that can have a significant impact on water systems and human health. Several methods can be used to treat the nitrate contained in the water, such as adsorption, phytoremediation, and wetland treatment. One of its methods was adsorption. The silica was modified with polymer due to its huge carbon chain. This research was focused on optimizing the ability of silica-based materials using PEG by physically coating them since PEG has a long carbon chain that could be transformed into a helix. In this research, the adsorbent will be prepared from modified silica gel with PEG 4000 by physical coating. Several parameters will be observed, including the effect of coating time, silica-PEG ratio, and PEG concentration. The capacity of silica-PEG to absorb NO3- is being studied. The characterization of functional group content in silica-PEG was carried out by Fourier Transform Infrared (FTIR). The study results show that the coating time was 10 minutes with the ratio of silica to PEG of 1:5, and the concentration of PEG used was 15%, indicating the optimum performance of silica-PEG when used as an absorbent, which achieved 84.44 % nitrate removal. An increase in the absorption capacity of silica-PEG demonstrates the ability of silica-PEG as a porous material. It was compared to silica gel without the PEG coating process, which was 9.09% to 84.44%.Abstrak: Semua kegiatan produksi pada akhirnya akan menghasilkan limbah, terutama limbah cair. Limbah cair biasanya akan bermuara di sungai dan berakhir di laut. Salah satu zat dalam limbah cair adalah ion nitrat (NO3-) yang mana dalam jumlah banyak dapat mengganggu sistem perairan dan kesehatan. Beberapa metode dapat digunakan untuk mengolah nitrat yang terkandung dalam air, seperti adsorpsi. Salah satunya dimodifikasi dengan polimer karena memiliki rantai karbon yang besar. Penelitian ini dikonsentrasikan untuk menyelidiki optimalisasi kemampuan silika dengan PEG dengan pelapisan fisik karena PEG memiliki rantai karbon panjang yang dapat bertransformasi menjadi heliks. Dalam penelitian ini, adsorben akan dibuat dari silika gel termodifikasi dengan PEG 4000 dengan pelapisan fisik. Beberapa parameter yang akan diamati antara lain pengaruh waktu pelapisan, rasio silika-PEG, konsentrasi PEG, dan temperatur pelapisan. Kinerja silika-PEG untuk menyerap NO3- diselidiki. Karakterisasi kandungan gugus fungsi pada silika-PEG dilakukan dengan Fourier Transform InfraRed (FTIR). Hasil penelitian menunjukkan bahwa waktu pelapisan adalah 10 menit dengan perbandingan silika dan PEG 1:5, dan konsentrasi PEG yang digunakan adalah 15%, menunjukkan kinerja silika-PEG yang optimum bila digunakan sebagai penyerap NO3-. Kemampuan silika-PEG sebagai bahan berpori dibuktikan dengan peningkatan kapasitas penyerapan silika-PEG dibandingkan silika gel tanpa proses pelapisan PEG.
PubDate: 2022-12-31
DOI: 10.22373/ekw.v8i2.14680
Issue No: Vol. 8, No. 2 (2022)
- Characterization of Carrageenan Edible Film With Natural Antioxidant From
Syzygium Cumini Leaf Extract (SCLE)
Authors: Reni Silvia Nasution
Pages: 54 - 64
Abstract: : Edible film have received considerable attention because of their advantages including their use as edible packaging material over synthetic films. This study aimed to characterize an edible film based on carrageenan and Syzygium cumini leaf extract (SCLE) as a natural antioxidant. The addition of SCLE was carried out with various concentrations of 0, 5, 10 and 15%. Characterization was carried out by measuring the physical properties, mechanical properties and antioxidant activities. The result showed that the presence of SCLE gave an increase in thickness and a decrease in solubility and water content compared to the edible film without the addition of SCLE. The addition of 5% SCLE resulted in a slight increase in tensile strength and a reduction in elongation at break. The edible films also showed an increase in antioxidant activity with the addition of SCLE where the highest antioxidant activity was at the addition of 15% SCLE. The incorporation of natural antioxidants in edible films can be a potential strategy to produce promising active packaging to extend product shelf life in the food packaging industry.Abstrak: Edible film telah mendapat banyak perhatian karena keuntungannya sebagai kemasan yang dapat dimakan dibandingkan film sintetik. Tujuan dari penelitian ini adalah untuk mengkarakterisasi edible film berbasis karaginan dan ekstrak daun Syzygium cumini (SCLE) sebagai antioksidan alami. Penambahan SCLE dilakukan dengan variasi konsentrasi 0, 5, 10 dan 15%. Karakterisasi dilakukan dengan mengukur sifat fisika, sifat mekanik dan aktivitas antioksidannya. Hasil menunjukkan bahwa keberadaan SCLE memberikan peningkatan pada ketebalan dan penurunan pada kelarutan dan kadar air dibandingkan edibe film tanpa penambahan SCLE. Penambahan SCLE sebanyak 5% menghasilkan sedikit peningkatan pada kuat tarik dan pengurangan pada perpanjangan putus. Edible film juga menunjukkan peningkatan aktivitas antioksidan dengan penambahan SCLE dimana aktivitas antioksidan tertinggi pada penambahan 15% SCLE. Penggabungan antioksidan alami pada edible film dapat menjadi strategi potensial untuk menghasilkan kemasan aktif yang menjanjikan untuk memperpanjang umur simpan produk pada industri kemasan makanan.
PubDate: 2022-12-31
DOI: 10.22373/ekw.v8i2.10966
Issue No: Vol. 8, No. 2 (2022)
- Effluent Quality Test On The Communal WWTP in Banda Aceh City
Authors: Ikhwanul Muslimin, Izarul Machdar, Nasrul Arahman
Pages: 65 - 78
Abstract: : One of the domestic wastewater management systems developed in Banda Aceh City is a settlement-scale centralized wastewater treatment plant, also known as the Communal WWTP system, with an anaerobic baffled reactor (ABR) and anaerobic filter (AF) configuration. This study aims to examine the quality of the effluent from the treatment of communal WWTPs in the city of Banda Aceh. Measurements of the contents of pH, BOD, COD, TSS, Ammonia, and Total Coliform were carried out on effluent samples from the communal WWTP and the results of the analysis were compared with the quality standards from the Minister of Environment and Forestry Regulation No. 68 of 2016 concerning Domestic Wastewater Quality Standards. The research showed that the pH, COD, BOD, and Ammonia parameters had met the quality standards, while the TSS and Total Coliform parameters at the five (5) locations of the communal WWTP studied had not shown effective performance and had not met the quality standards. The choice of technology configuration and management of communal WWTP is a factor that influences the processing performance and quality of communal WWTP effluent in Banda Aceh City.Abstrak: Salah satu sistem pengelolaan air limbah domestik yang dikembangkan di Kota Banda Aceh adalah SPALD-Terpusat skala permukiman, atau disebut juga dengan sistem IPAL Komunal, dengan konfigurasi anaerobic baffled reactor (ABR) dan anaerobic filter (AF). Penelitian ini bertujuan untuk menguji kualitas efluen hasil pengolahan IPAL komunal yang ada di kota Banda Aceh. Pengukuran kandungan pH, BOD, COD, TSS, Amonia serta Total Coliform dilakukan pada sampel efluen dari IPAL komunal dan hasil analisisnya dibandingkan dengan baku mutu Peraturan Menteri Lingkungan Hidup dan Kehutanan No. 68 Tahun 2016 tentang Baku Mutu Air Limbah Domestik. Penelitian menunjukkan parameter pH, COD, BOD dan Amonia telah memenuhi baku mutu sedangkan parameter TSS dan Total Coliform pada lima (5) lokasi IPAL komunal yang diteliti belum menunjukkan kinerja yang efektif dan belum memenuhi standar baku mutu. Pemilihan konfigurasi teknologi dan pengelolaan IPAL komunal menjadi faktor yang mempengaruhi kinerja pengolahan dan kualitas efluen IPAL komunal di Kota Banda Aceh.
PubDate: 2022-12-31
DOI: 10.22373/ekw.v8i2.11775
Issue No: Vol. 8, No. 2 (2022)
- Spatial Distribution of Groundwater Salinity In The Coastal Area of Aceh
Besar District
Authors: Muhammad Kalbadri, Ichwana Ramli, Muhammad Faisal
Pages: 287 - 297
Abstract: : Utilization of groundwater sources is still an alternative for people living in the coastal areas of Aceh Besar District. If the use of groundwater is carried out continuously, it will have a negative impact on the quality and quantity of groundwater. So the purpose of this study was to determine the distribution of groundwater salinity in the coastal areas of Aceh Besar District. The sample points were determined based on the random sampling method in grids. Sample testing for groundwater salinity was carried out directly in the field according to the planned location. The data obtained was inputted into Microsoft excel and mapping of groundwater salinity distribution using the Inverse Distance Weight (IDW) method with Argis software. A correlation test was performed with Pearson Product Moment. Based on the measurement results, 20 sample points of high salinity were measured. The distribution of salinity values also has a relationship with coastal distance, where the distribution of salinity in general, the farther the groundwater is from the coast, the lower the salinity value, and the closer the groundwater to the coast, the higher the salinity.Abstrak: Pemanfaatan sumber air tanah masih menjadi alternatif bagi masyarakat yang tinggal di wilayah pesisir Kabupaten Aceh Besar. Jika pemanfaatan air tanah dilakukan secara terus-menerus akan berdampak negatif secara kualitas dan kuantitas air tanah. Sehingga tujuan penelitian ini adalah untuk mengetahui sebaran salinitas air tanah di wilayah pesisir Kabupaten Aceh Besar. Titik sampel ditentukan berdasarkan metode random sampling in grids. Pengujian sampel untuk salinitas air tanah dilakukan langsung di lapangan sesuai dengan lokasi yang telah direncanakan. Data yang diperoleh diinput ke dalam Microsoft excel dan pemetaan distribusi salinitas air tanah menggunakan metode Inverse Distance Weight (IDW) dengan perangkat lunak Argis. Uji korelasi dilakukan dengan Pearson Product Moment. Berdasarkan hasil pengukuran, nilai salinitas yang tinggi terukur sebanyak 20 titik sampel. Nilai salinitas tinggi pada umumnya dipengaruhi oleh intrusi air asin terhadap air tawar. Faktor sebaran salinitas air tanah terjadi akibat intrusi, penggunaan lahan yang dekat dengan tambak dan muara sungai, faktor sebaran salinitas juga dipengaruhi oleh kepadatan penduduk. Sebaran nilai salinitas juga memiliki hubungan dengan jarak pantai, dimana sebaran salinitas secara umum, semakin jauh air tanah dengan jarak pantai maka nilai salinitasnya semakin rendah, dan semakin dekat air tanah dengan jarak pantai maka salinitasnya semakin tinggi.
PubDate: 2022-12-31
DOI: 10.22373/ekw.v8i2.11719
Issue No: Vol. 8, No. 2 (2022)
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