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All Journal Jurnal Riset Kimia Indonesian Journal of Chemistry REACTOR : Journal of Research On Chemistry And Engineering Andalasian International Journal of Agricultural and Natural Sciences Andalasian International Journal of Applied Science, Engineering, and Technology Jurnal Abdi Inovatif : Pengabdian kepada Masyarakat
Yefrida -
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Agriculture, Biological Sciences & Forestry Humanities Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Environmental Science Industrial & Manufacturing Engineering Mechanical Engineering Social Sciences Other

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VALIDASI METODA FRAP MODIFIKASI PADA PENENTUAN KANDUNGAN ANTIOKSIDAN TOTAL DALAM SAMPEL MANGGA DAN RAMBUTAN -, Yefrida; Ashikin, Nor; -, 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.
UJI AKTIVITAS ANTI BAKTERI ASAP CAIR YANG BERASAL DARI BATANG KAYU MANIS DAN KULIT KACANG TANAH -, Yefrida; Aprilina, Farrah; Leone, Indri Ticel; -, 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    
PEMBUATAN ASAP CAIR DARI LIMBAH KAYU SUREN (Toona sureni), SABUT KELAPA DAN TEMPURUNG KELAPA (Cocos nucifera Linn) -, Yefrida; Putri, Yani Kasuma; Silvianti, Richi; Lucia, Novita; -, 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
VALIDASI METODA PENENTUAN ANTIOKSIDAN TOTAL (DIHITUNG SEBAGAI ASAM SITRAT) DALAM SAMPEL JERUK SECARA SPEKTOFOTOMETRI DENGAN MENGGUNAKAN OKSIDATOR FeCl3 DAN PENGOMPLEKS ORTO-FENANTROLIN -, Yefrida; Ulfaningsih, Mega; Loekman, Umiati
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.v7i2.187

Abstract

ABSTRACTAntioxidant is a compound that can be used to obstruct species oxygen reactive, speciesnitrogen, and other free radicals so it can be used degenerative illnesses inhibition. Citric acid isa natural antioxidant that can be found in some kind of oranges. There are some methode thatusually used to determination the antioxidant, such as CUPRAC, DPPH, and FRAP. Objectiveof this research is studied about alternative method to determine total antioxidant that is countedas citric acid by using FeCl3 as an oxidator and o-phenantroline as a complexant reagent. Instudied of appropriateness of this method, validation has been done with parameter linearity,LoD, LoQ, SDR, and recovery with samples orange, kaffir lime, and lime. Base on the research,the regression equation is Y = 0,066 + 117.35 X and R2 = 0.990 with value of LoD is1.15x10-3M and LoQ is 3.86x10-3 M. The value of SDR and recovery in samples orange, kaffir lime, andlime are 1.64%, 0.53% 2.14%, and 100.47%, 93.58%, 93.78%, respectively. Base on validationmethod data, can be concluded that this method appropriate to be used to determination of totalantioxidant for samples orange, kaffir lime, and lime.Keywords : Antioxidant, Validation Method, Spectrophotometry
UJI AKTIVITAS ANTIMIKROBA SERTA ANTIOKSIDAN ASAP CAIR CANGKANG SAWIT (Elaeis gueneensis jack) -, Yefrida; -, Refilda; -, Indrawati; Siregar, Irma Yanti
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.   
Validasi Metode MPM untuk Penentuan Kandungan Antioksidan dalam Sampel Herbal serta Perbandingannya dengan Metode PM, FRAP dan DPPH Yefrida, Yefrida; Suyani, Hamzar; Aziz, Hermansyah; Efdi, Mai
Jurnal Riset Kimia Vol 11, No 1 (2020): March
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v11i1.342

Abstract

The Modified Phenanthroline Method (MPM) has been validated for determination of antioxidant content in herb samples. Validation was done using Relative Standard Deviation (RSD) and percentage of recovery. The RSD and percentage of recovery for herb samples are 3.13% and 98.6%, respectively. Based on these values, MPM method is valid for determining antioxidant content in herb samples. T test shows no significant differences of antioxidant content using any of these methods, MPM, PM, FRAP or DPPH, at a 95% confidence level. MPM method shows a very strong correlation with PM and FRAP method.  While with DPPH and TPC shows is strong.
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; Hamidah, Nofi; Rosman, Widuri
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.
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.   
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    
Co-Authors Afdhal Muttaqin Aldini, Tasya Ardiani, Ajeng Putri Ashikin, Nor Boneta, Fella Krisna Deliza, Deliza Efendi Efendi Farrah Aprilina Fuji Astuti Febria Hamidah, Nofi Hamzar Suyani Hermansyah Aziz Ilham, Muhammad Samudra Indrawati - Indrawati Indrawati Indri Ticel Leone Irma Yanti Siregar Irmanida Batubara Mai Efdi Mairawita, Mairawita Mega Ulfaningsih Mildawati Mildawati Narwen Narwen Nasution, Ainun ndrawati - Novita Lucia RAMADANI, MUTIA Refilda Refilda Richi Silvianti Rosman, Widuri Safni Safni Solfiyeni Solfiyeni Syafwan, Mahdivan Umiati Loekman Umiati Loekman Yani Kasuma Putri Zilfa Zilfa Zulfi, Zulfi