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All Journal Jurnal Riset Kimia Jurnal Litbang Industri CHEMPUBLISH JOURNAL Jurnal Kimia Mulawarman Chimica et Natura Acta Indonesian Journal of Chemistry Jurnal Penelitian Farmasi dan Herbal Warta Pengabdian Andalas: Jurnal Ilmiah Pengembangan Dan Penerapan Ipteks Andalasian International Journal of Agricultural and Natural Sciences Andalasian International Journal of Applied Science, Engineering, and Technology Jurnal Litbang Industri Inisiatif: Jurnal Ekonomi, Akuntansi Dan Manajemen Jurnal Katalisator
Refilda Refilda
Fakultas MIPA, Universitas Andalas
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Decision Sciences, Operations Research & Management Economics, Econometrics & Finance Electrical & Electronics Engineering Energy Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Medicine & Pharmacology Social Sciences Other

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PEMBUATAN ASAP CAIR DARI LIMBAH KAYU SUREN (Toona sureni), SABUT KELAPA DAN TEMPURUNG KELAPA (Cocos nucifera Linn) Yefrida -; Yani Kasuma Putri; Richi Silvianti; Novita Lucia; Refilda -; ndrawati -
Jurnal Riset Kimia Vol. 1 No. 2 (2008): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v1i2.85

Abstract

  ABSTRACT The waste of red cedar wood, coconut husk and coconut shell has not been well used. They had been used as traditional cooking fuel and also direct food smoking process by community, but they still had several disadvantages. Those could be treated by the simple processing, they can produce new high economics product. In this research, the use of waste red cedar wood, coconut husk and coconut shell as resources of liquid smoke by pyrolization followed by condensation has investigated. Liquid smoke is condensates of smoke which have experienced storage and screening to separate the tar and particulate matter.   Liquid smoke that was produced were different in color and smells, light brown and smells of smoke of red cedar wood burn, blackness of brown and smells like burning smoke of coconut husk and brown with smelled like the smoke of burned coconut shell. The pH of liquid smoke of red cedar wood was 3.34, liquid smoke of coconut husk is 3.48 and liquid smoke of coconut shell was 3.21, where its value was influenced by the component of acid which were the biggest component in coconut shell liquid smoke. The result of characterization using GC/MS indicated that there were 27 compounds and the main component of liquid smoke of red cedar wood is acetic acid (45.17%), 2-propanone (15.75%), 1-hidroxy-2-propanone (7.36%), furfural (5.50%) and phenol (4.17%), 27 compounds with the main component of liquid smoke of coconut husk is acetic acid (42.00 %), phenol (25.99%), 2-propanone (7.04%), furfural (4.06%) and guaiacol (3.32%), and 37 compounds with the main component of coconut shell liquid smoke are acetic acid (51.99%), phenol (19.90%), methyl acetate (5.37%), furfural (4.56%), hydroxyl acetone (2.90%), guaiacol (2.62%) and syringol (1.85%).  Keywords: waste red cedar wood, coconut husk, coconut shell, liquid smoke,  GC/MS
UJI AKTIVITAS ANTIMIKROBA SERTA ANTIOKSIDAN ASAP CAIR CANGKANG SAWIT (Elaeis gueneensis jack) Yefrida -; Refilda -; Indrawati -; Irma Yanti Siregar
Jurnal Riset Kimia Vol. 4 No. 2 (2011): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v4i2.135

Abstract

  ABSTRACT Liquid smoke is one of natural preservative. It can make from many sources such as coconut shell, wood, etc. In this study, it is made from the palm kernel shell (Elaeis gueneensis jack) by using pirolysis method. Its contains is determined by GC-MS, while antimicrobial activity by Kirby-Bauer method and antioxidant activity by DPPH method. From the test, it can be concluded that this liquid smoke contains carboxylic acids, fenol and its derivative compound as a major component and has a good enough antimicrobial and antioxydant activity. Keywords : liquid smoke, pirolysis, antimicrobial, antioxvdant.   
OPTIMATION STUDY OF CARRAGEENAN EXTRACTION FROM RED ALGAE (Eucheuma cottonii) Refilda -; Edison Munaf; Rahmiana Zein; Abdi Dharma; Indrawati -; Lee Wah Lim; Toyohide Takeuchi
Jurnal Riset Kimia Vol. 2 No. 2 (2009): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v2i2.151

Abstract

 ABSTRACT Carrageenan is a general name for polysacharides, it is made up of sodium, potassium, magnesium, and calcium sulphat esters of galactose and 3.6-anhydrogalactose units. Research about parameters influencing extraction process of carrageenan from red algae (Eucheuma cottonii) has been studied. The parameters were particle size of red algae, pH of NaOH solution, heating time and heating temperature. About 64.30% of carrageenan was extracted from red algae (Eucheuma cottonii) under optimum condition, 425 µm particle size of red algae, solution pH 8.5, heating time 18 h, and heating temperature 95°C. The FTIR spectra of extracted carrageenan showed the same spectra as the pure carrageenan. Keywords : carrageenan, red algae (Eucheuma cottonii), and extraction    
UJI AKTIVITAS ANTI BAKTERI ASAP CAIR YANG BERASAL DARI BATANG KAYU MANIS DAN KULIT KACANG TANAH Yefrida -; Farrah Aprilina; Indri Ticel Leone; Refilda -
Jurnal Riset Kimia Vol. 2 No. 2 (2009): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v2i2.161

Abstract

 ABSTRAK Antibacterial agent is a compound that prevent the growth and reproduction of bacteria. Antibacterial activity of liquid smoke is caused by acid and fenolic compound. In this research, we determined antibacterial activity of liquid smoke from stem sweet wood  and nut shell by using diffusion method. Both of liquid smoke have antibacterial activity to Staphylococcus aureus  Eschericia coli population. Their activity almost the same to chloramphenicol, but less than formalin. Keywords : antibacterial activity, liquid smoke, diffusion method    
PENENTUAN KANDUNGAN LOGAM ESENSIAL (Fe, Zn DAN Cu) DALAM DAUN SIRIH MERAH (Piper crocatum) SEGAR, AIR REBUSAN DAN AIR SEDUHANNYA DENGAN METODE SPEKTROSKOPI SERAPAN ATOM(SSA) Indrawati -; Willsant Saputra; Refilda -
Jurnal Riset Kimia Vol. 7 No. 2 (2014): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v7i2.171

Abstract

Vol 7 No 2ABSTRACTDetermination of essential metals (Fe, Zn and Cu) in red betel leaf has been carried out by usingAtomic Absorption Spectrophotometer (AAS). Fresh and dry red betel leaf extracted in 75 mLby boiled and brewed distilled water for 5, 10, 15 and 20 minutes. In the fresh red betel leafmetal content (Fe, Zn and Cu) were 0,3257 %, 0,173 % and 0,0278 % and the highest metalcontent (Fe, Zn and Cu) found in dry red betel leaf which were boiled for 20 minutes with theconcentration 0,0539 %, 0,0305 % and 0,0128 %. Red betel leaf is a source of essential metalsneeded by the body.Keywords: Atomic Absorption Spectrophotometry (AAS), Red betel leaf (Piper crocatum),decoction water, steeping water, Fe, Zn and Cu
STUDI OPTIMASI PENENTUAN UNSUR HARA BESI DALAM CAMPURAN TANAH DAN KOMPOS MENGGUNAKAN METODE SPEKTROFOTOMETRI Refilda -; Suhartini -; Indrawati -
Jurnal Riset Kimia Vol. 8 No. 2 (2015): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v8i2.231

Abstract

Determination of iron nutrient content in a mixture of soil and compost with spectrophotometric method has been carried out. Metal ions Fe(II) complexed with 0.1% ortho-fenantrolin 2 mL, 0.01 M citric acid as reducing  agent  using acetat buffer at pH 4.5 and its complex was measured by using spectrophotometer UV/Vis at wavelength 515 nm, the complex stability for was 60 minutes . The highest nutrient of iron with content in soil:compost with ratio of 0.8:0.2 was 0.92% at incubation time 30 days. The lowest iron content in the mixture of soil:compost (1:0) at incubation time for  15 days was 0.58% that obtained by the regression equation y = 95.85x + 0.025 with R2=0.992. The level of nutrient iron in compost obtained lower than the maximum regulated by SNI 2.00%.
VALIDASI METODA FRAP MODIFIKASI PADA PENENTUAN KANDUNGAN ANTIOKSIDAN TOTAL DALAM SAMPEL MANGGA DAN RAMBUTAN Yefrida -; Nor Ashikin; Nor Ashikin; Refilda -; Refilda -
Jurnal Riset Kimia Vol. 8 No. 2 (2015): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v8i2.236

Abstract

Validation of modified FRAP method to determine total antioxidant content in mango and rambutan sample have been done. Total antioxidan content in sampel is presented as Gallic Acid Equivalent (GAE). Modified FRAP method using FeCl3asoxidizing agent and ortho-phenantroline as complexan, which produce complex compounds of [Fe (C12H8N2)3]+2 sorrel coloured. Validation parameters are obtained in this research are r = 0.999, R2 = 0.998, LoD 3.13 x 10-6 M and LoQ 1.04 x 10-5 M. While RSD and recovery in the sample mango and rambutan were 1.15%, 1.34% and 96.31%, 97.72%, respectively. Based on the value of the validation parameters, it can be concluded that this method can be used for determination of total antioxidant content in the mango and rambutan samples.
VALIDASI METODA FRAP MODIFIKASI PADA PENENTUAN KANDUNGAN ANTIOKSIDAN TOTAL DALAM SAMPEL MANGGA DAN RAMBUTAN Yefrida -; Nor Ashikin; Nor Ashikin; Refilda -; Refilda -
Jurnal Riset Kimia Vol. 8 No. 2 (2015): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v8i2.236

Abstract

Validation of modified FRAP method to determine total antioxidant content in mango and rambutan sample have been done. Total antioxidan content in sampel is presented as Gallic Acid Equivalent (GAE). Modified FRAP method using FeCl3asoxidizing agent and ortho-phenantroline as complexan, which produce complex compounds of [Fe (C12H8N2)3]+2 sorrel coloured. Validation parameters are obtained in this research are r = 0.999, R2 = 0.998, LoD 3.13 x 10-6 M and LoQ 1.04 x 10-5 M. While RSD and recovery in the sample mango and rambutan were 1.15%, 1.34% and 96.31%, 97.72%, respectively. Based on the value of the validation parameters, it can be concluded that this method can be used for determination of total antioxidant content in the mango and rambutan samples.
Penentuan Kandungan Antioksidan Total pada Infusa Selada Hijau (Lactuca sativa L.) Hidroponik dan Konvensional secara Spektrofotometri dengan Modified Phenantroline Method (MPM) Yefrida Yefrida; Refilda Refilda; Nofi Hamidah; Widuri Rosman
Jurnal Riset Kimia Vol. 13 No. 1 (2022): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i1.492

Abstract

Green lettuce is a vegetable that is widely consumed in Indonesia. These vegetables come from conventional and hydroponic farming. This study aims to compare the antioxidant content of these two types of vegetables. This vegetable is extracted by the infundation method. The extract obtained was determined for its antioxidant content by the MPM method. This method was validated by using parameter LoD, LoQ, linearity, precision and accuracy. The results showed that this method was valid for determining the total antioxidant content in conventional and hydroponic green lettuce samples. The total antioxidant content in conventional and hydroponic green lettuce samples was 2.68 ± 0.65 mg aa/g FW and 1.67 ± 0.40 mg AA/g FW, respectively. T test stated that the antioxidant content of the two samples was significantly different.
Biosorben cangkang pensi (Corbicula moltkiana) sebagai penyerap zat warna metanil yellow ditinjau dari pH dan model kesetimbangan adsorpsi Rahmiana Zein; Putri Ramadhani; Hermansyah Aziz; Refilda Suhaili
Jurnal Litbang Industri Vol 9, No 1 (2019)
Publisher : Institution for Industrial Research and Standardization of Industry - Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (374.781 KB) | DOI: 10.24960/jli.v9i1.4661.15-22

Abstract

Penelitian cangkang pensi (Corbicula moltkiana) sebagai penyerap zat warna metanil yellow telah dilakukan dengan sistem batch. Kondisi optimum penyerapan terjadi pada pH 4 dan konsentrasi awal 100 mg/L. Proses adsorpsi terjadi mengikuti model isoterm Langmuir dengan nilai R2 adalah 0,886 pada monolayer dengan kapasitas adsorpsi maksimum (qmax) diperoleh 2,591 mg/g. Hasil analisis gugus fungsi cangkang pensi dengan FTIR menunjukkan adanya interaksi antara molekul zat warna metanil yellow dan gugus fungsi. Analisis morfologi permukaan cangkang pensi menggunakan SEM menunjukkan bahwa pori-pori cangkang pensi telah diisi oleh molekul zat warna metanil yellow. Cangkang pensi dapat digunakan sebagai bahan penyerap zat warna metanil yellow di dalam larutan. ABSTRACTThe study of the Pensi Shell (Corbicula moltkiana) to adsorb metanil yellow (MY)dyes  has been investigated. This study was determined by batch system. The optimum conditions of metanil yellow dyes adsorption occurred at pH 4 and initial concentration 100 mg/L. The adsorption process was properly described by Langmuir isotherm model which was indicated by the value of R2=0,886. This confirmed that the adsorption process was monolayer with maximum adsorption capacity (qmax) was 2,591 mg/g. Functional groups analysis by FTIR showed the interactions MY molecule on pensi shell functional groups. Analysis of morphology surface of pensi shell by SEM indicated that the pore was filled by MY molecules. Pensi shell could be used as adsorbent of metanil yellow dyes in aqueous solution.
Co-Authors -, Yefrida Abdi Dharma Adewirli Putra Admi Admi Admi Admi Ainun Nasution Akmal Djamaan Ardiani, Ajeng Putri Ashikin, Nor Boneta, Fella Krisna Dheasy Gustira Dheasy Gustira Dini Hanifa Dwi Syukur Phameswari Edison Munaf Edison Munaf Elida Mardiah Emil Salim Farrah Aprilina Fella Krisna Boneta Fivi Mona Bareno Hamidah, Nofi Harza Dipajana Umardi Harza Dipajana Umardi Hayatul Isra Hermansyah Aziz Hermansyah Aziz Ilahi, Fitratul Imelda Imelda Imelda Imelda Indrawati - Indrawati - Indrawati Indrawati Indri Ticel Leone Irma Yanti Siregar Irmanida Batubara Jihanul Khaira Jihanul Khaira Jon Kanedi Lee Wah Lim Lucy Prima Ardi Mai Efdi Matlal Fajri Alif Mayaserli, Dyna Putri Mutia Ramadani ndrawati - Nofi Hamidah Nofita, Dewi Nor Ashikin Nor Ashikin Norman Ferdinal Novesar Jamarun Novita Lucia Novrizaldi Wardana Nurul Afifah Putri Ramadhani Rahmiana Zein Raihan Hanif Aulia Refinel - Richi Silvianti Riga Habib Ngestu Rosman, Widuri Safni Safni Salim, Emil Silvia Detri Susanti Suhartini - SUHARTINI - Sumaryati Syukur Suryati Suryati Syafrizayanti Syafrizayanti Syukri Syukri Tommi Hermansyah Toyohide Takeuchi Upita Septiani Wellia, Diana Vanda Widuri Rosman Willsant Saputra Yani Kasuma Putri Yefrida - Yefrida Yefrida Yetria Rilda Yulizar Yusuf Zilfa Zilfa Zulkarnain Chaidir