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All Journal Jurnal Riset Kimia Jurnal Kimia Mulawarman Warta Pengabdian Andalas: Jurnal Ilmiah Pengembangan Dan Penerapan Ipteks Andalasian International Journal of Applied Science, Engineering, and Technology AJARCDE (Asian Journal of Applied Research for Community Development and Empowerment) Jurnal Katalisator Jurnal Kimia Unand
Yefrida
Departemen Kimia FMIPA Unand
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Earth & Planetary Sciences Education Electrical & Electronics Engineering Energy Environmental Science Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Medicine & Pharmacology Social Sciences Other

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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 Metode MPM untuk Penentuan Kandungan Antioksidan dalam Sampel Herbal serta Perbandingannya dengan Metode PM, FRAP dan DPPH Yefrida Yefrida; Hamzar Suyani; Hermansyah Aziz; Mai Efdi
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; 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.
Teknik Edible Coating dengan menggunakan Campuran Gel Lidah Buaya dan Ekstrak Daun Psidium guajava L. untuk Mempertahankan Sifat Fisikokimia Buah Jambu Biji Refilda Refilda; Riga Habib Ngestu; Emil Salim; Yefrida
Jurnal Riset Kimia Vol. 13 No. 2 (2022): September
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jrk.v13i2.501

Abstract

The synthetic chemicals is a common substance used to extend the shelf life of postharvest fruit. But it can have health impact. The use of edible coatings from natural ingredients has begun to be developed. Modification of aloe vera gel by guava leaf extract as the edible coating to increase guava fruit shelf life has not been reported yet. Guava fruit coated by several compositions of aloe vera gel and guava leaf extract have been carried out. Observations on physichochemical in fruit on the days 0, 3, 6, 9, 12 and 15 were evaluated. The best quality found on guava fruit treated with the compotition of aloe vera gel:ethanol guava leaf extract: CMC:glycerol (90: 5:0.25: 0.5) on the day 15. It had a weight loss of 9.88%, a spoilage of 3.33%, the decrease of water content 11.61%, titratable acidity 0.5%, total antioxidant 1.08 mg AA/g FW, total phenolic 0.51 mg GAE/g FW, and increase of total dissolved solids 3.01 oBrix. This result was significantly better than the uncoated fruit. It can be concluded that guava leaf extract can be used to maintain the physicochemical properties during storage.
Penentuan Kandungan Antioksidan dan Fenolik Total dari Infusa Daun Tanaman Famili Myrtaceae Secara Spektrofotometri Yefrida; Hayatul Isra; Refilda
Jurnal Kimia Unand Vol. 11 No. 1 (2022): May 2022
Publisher : Departemen Kimia Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jku.11.1.6-11.2022

Abstract

Myrtaceae family plants are widely distributed in the tropics. The leaves of this plant have been widely used by the community as a traditional medicine. This study aims to determine the total antioxidant and total phenolic content of the infusion of five types of leaves of the Myrtaceae family, namely bay leaves (Syzygium polyanthum), jambak leaves (Syzygium malaccense), guava leaves (Psidium guajava), water guava leaves (Syzygium aqueum). and duwet leaves (Syzygium cumini). Total antioxidant content was determined using the MPM method and total phenolic content using the Folin Ciocalteau method. The highest total antioxidant content was found in jambak leaf infusion of 122.73 ± 3.10 mg AA/g DW, while the highest total phenolic content was found in guava leaf infusion of 58.84 ± 1.86 mg GAE/g DW.
A mixture of Aloe Vera Gel (Aloe vera. L) and Sungkai Leaf Extract (Peronema canescens. Jack) as Edible Coating to Increase Tomato (Solanum lycopersicum) Storage Life Yefrida Yefrida; Fella Krisna Boneta; Refilda Refilda
Andalasian International Journal of Applied Science, Engineering and Technology Vol. 4 No. 2 (2024): July, 2024
Publisher : LPPM Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/aijaset.v4i2.122

Abstract

Tomatoes are climacteric fruits, are well-known for containing lycopene is an antioxidant. The post-harvest shelf life of harvested tomatoes is only 4-5 days. This research aims to optimize previous methods such the use of plastic packaging and cold storage methods were found to be inefficient and produced waste, so it is necessary to renew them by using the edible coating method, a natural ingredient from Aloe vera. L gel, while sungkai leaf extract (Peronema canescans. Jack) shows the effectiveness of edible coating could potentially provide a protective barrier against external factors, helping to maintain the quality of tomatoes and waste reduction. Edible coating material from aloe vera gel added with sungkai leaf extract of various compositions (C, EC1, EC2, EC3, EC4, and EC5) was prapare and applied to tomatoes. Fourier Transform Infrared (FTIR) testing was carried out to determine the functional groups in all edible coating materials. Physicochemical properties tests were carried out on tomatoes. The results obtained by EC5 the lowest weight loss 11.14%, while EC4 was the best edible coating material in percent decay 8.89%, total dissolved solids 1.00oBrix, total antioxidant 0.024 mg AA/g FW, and total phenolic 0.224 mg GAE/g FW for 15 days compared to aloe vera gel coating (EC1), which only lasted for 9 days, and uncoated (C), which only lasted for 6 days. Keywords: Edible coating, physicochemical properties, FTIR
Determination of Total Antioxidant and Phenolic Content from Malvaceae Family Leaves Infusion by Spectrophotometry Yefrida Yefrida; Silvia Detri Susanti; Refilda Refilda
JURNAL KIMIA MULAWARMAN Vol 21 No 1 (2023)
Publisher : Jurusan Kimia Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Mulawarman

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30872/jkm.v21i1.1007

Abstract

The use of plants as a source of medicine has been increasing lately. The plants used generally have bioactivities such as anti-bacterial, antioxidant, and others. Plants that contain antioxidants are widely used because of their ability to capture free radicals so that they can protect the body from various diseases. One of the plants that is often used is plants from the Malvaceae family. In this study, the antioxidant and total phenolic contents of five types of plants were determined. These plants were extracted by infundation method and analyzed using MPM (Modified Phenanthroline Method) and Folin-Ciocalteu methods. The highest antioxidant and total phenolic contents were found in kapok randu and waru leaves.
PENENTUAN ASAM GALAT DAN KUERSETIN DALAM BEBERAPA TANAMAN OBAT MENGGUNAKAN METODE KCKT Refilda; Nindi Rahmi Amelia; Dini Hanifa; Yefrida
JURNAL KATALISATOR Vol. 8 No. 2 (2023): Jurnal Katalisator Volume 8 No. 2, Oktober 2023
Publisher : LLDIKTI X Sumbar, Riau, Jambi, Kepri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.62769/katalisator.v8i2.2231

Abstract

Senyawa flavonoid yang memiliki sifat antioksidan dan dapat menghambat radikal bebas diantaranya adalah asam galat dan kuersetin. Kandungan asam galat dan kuersetin dalam tanaman herbal yang sering dikonsumsi masyarakat belum banyak dilaporkan. Pada penelitian ini dilakukan penentuan asam galat dan kuersetin yang terdapat dalam ekstrak air daun belimbing wuluh (Averrhoa bilimbi L.), daun jambu bol (Syzygium malaccense), daun jeruk purut (Citrus hystrix), daun pepaya (Carica papaya L.), daun alpukat (Persea americana Miller.), daun salam (Syzygium polyanthum), daun sirih merah (Piper crocatum), daun sirsak (Annona muricata) menggunakan metode Kromatografi Cair Kinerja Tinggi (KCKT). Ekstraksi sampel dalam pelarut air dengan bantuan gelombang ultrasonik. Kondisi pemisahan asam galat dan kuersetin dilakukan dengan fasa gerak campuran asetonitril:asam fosfat 0,02% (10:90), fasa diam berupa kolom C18, kecepatan alir 0,7 mL/menit, detektor DAD, dan panjang gelombang 260 nm. Asam galat dan kuersetin terpisah pada waktu retensi 2,114 dan 2,883 menit. Berdasarkan kondisi ini diperoleh kandungan asam galat tertinggi 0,0402 mg/gFW pada ekstrak daun jambu bol, dan terendah 0,0027mg/gFW pada ekstrak daun sirih merah. Kuersetin hanya terdapat pada ekstrak air daun belimbing wuluh sebesar 0,185 mg/gFW. Informasi ini dapat menjadi landasan untuk pengembangan produk-produk herbal atau suplemen kesehatan yang mengandung senyawa-senyawa ini
Training on Postharvest Guava Fruit Processing in KWT Jambu Biji, VII Koto Sungai Sariak, Pariaman Yefrida Yefrida; Refilda Refilda; Imelda Imelda; Refinel Refinel; Rahmiana Zein; Safni Safni; Admi Admi; Dheasy Gustira; Jihanul Khaira; Harza Dipajana Umardi
Warta Pengabdian Andalas Vol 31 No 3 (2024)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat (LPPM) Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jwa.31.3.510-517.2024

Abstract

Red guava fruit is one type of fruit that quickly changes colour, texture and spoilage. This is of course a problem for farmers. At harvest time, not all of the fruit is marketable. So sometimes farmers just leave the fruit on the tree, because if harvested it will only increase operational costs. The KWT Jambu Biji Bengke Sakato, VII Koto Sungai Sariak, Pariaman is a group of red guava farmers. They tried to find a solution to this problem by discussing with TIM PPM KIMIA UNAND of the Department of Chemistry, FMIPA, Universitas Andalas. Finally it was agreed that the solution was to make products from red guava. The products made in this program are dodol and red guava ice cream. The KWT members and the Tim PPM KIMIA UNAND together made these two types of products. The results obtained, dodol and ice cream made are quite delicious and have an attractive appearance. This product can be an alternative to red guava processing that has economic value.
Flavonoid, Phenolic and Antioxidant Content in Several Parts of the Artemisia Plant Yefrida; Yola Tsurayya Putri; Refilda
Jurnal Kimia Unand Vol. 14 No. 1 (2025): May 2025
Publisher : Departemen Kimia Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jku.14.1.24-28.2025

Abstract

Free radicals can cause damage to cells in the body. This can be prevented or treated by using substances that are antioxidants. Artemisia plants (Asteraceae family) are one of the potential sources of natural antioxidants. This study was conducted to determine the content and correlation of flavonoids, phenolics and antioxidant activity of leaves, stems and roots of four types of Artemisia genus plants. The method used for the determination of total flavonoid content was the AlCl3 method and the Folin-Ciocalteau method for the determination of total phenolic content. Antioxidant activity was determined by DPPH methods. Based on this study, with the exception of Artemisia vulgaris plants, the antioxidant activity was determined by DPPH and MPM methods., which had the highest quantity in the roots, the leaves contained the highest levels of flavonoids and total phenolics relative to other sections. The data obtained were further tested with ANOVA which showed a significant difference between flavonoid content, phenolic content, and antioxidant activity with plant type and plant part.
Co-Authors Admi Admi Ardiani, Ajeng Putri Dheasy Gustira Dini Hanifa El Firsti, Nurjannah Elinda Fithriana Etriyanto Arman Fella Krisna Boneta Hamzar Suyani Harsita, Wanda Dwi Harza Dipajana Umardi Hayatul Isra Hayatul Isra Hermansyah Aziz Humaira, H Imelda Imelda Isra, Hayatul Jihanul Khaira Mai Efdi Nindi Rahmi Amelia Nofi Hamidah Nor Ashikin Nor Ashikin R Refilda Rahmiana Zein Refilda Refilda Refilda Refilda Refinel - Riga Habib Ngestu Safni Safni Salim, Emil Silvia Detri Susanti Widuri Rosman Y.T. Putri Yola Tsurayya Putri