Validation of UV-Vis Spectrophotometric Method of Quercetin in Ethanol Extract of Tamarind Leaf

Abstract

Tamarindus indica L is a medicinal plant that has many benefits. One of the chemical compounds contained therein is the flavonoid quercetin type. The number of herbal products on the market makes the quality assurance of herbal products need to be done by performing the assay of the active compounds using validated methods. This study aims to validate the assay method quercetin in the extract of tamarind leaves. Tamarind leaf extract was macerated with hexane; then, it was re-macerated with 70% ethanol. The extract was concentrated using a rotary evaporator. The assay was performed using the UV-Vis Spectrophotometry method, and parameter validation specified in this study, including linearity, LOD, LOQ, precision, and accuracy. Quercetin level obtained in extracts of tamarind leaves was at 21.52 mg/g. Based on the test method validation, the correlation coefficient (r) was 0.9999, the regression function coefficients (Vx0) was 0.59545%, LOD 0.1515 ppm, LOQ 0.4592 ppm, coefficient of variation precision was < 2%, and recoveries range was in 97-103%.

Validasi dari Spektrofotometri UV-Vis dan Kandungan Total Flavonoid Ekstrak Etanol dari Akar Alang-Alang (Imperata cylindrica) dan Daun Pegagan (Centella asiatica) Anita Puspa Widiyana

“…(1) Sampel yang telah diketahui dapat digunakan untuk menghitung parameter validasi meliputi akurasi, presisi, linearitas, dan karakteristik lainnya dari kinerja suatu metode. (2)(3)(4) Pegagan (Centella asiatica Linn) dan alang-alang (Imperata cylindrica (L) Beauv) merupakan tanaman yang banyak ditemukan di Indonesia. Pada umumnya daun pegagan dikonsumsi sebagai sayuran hijau maupun salad, sedangkan alang-alang dimanfaatkan akarnya sebagi bahan minuman.…”

Signal-Enhanced Electrochemical Determination of Quercetin with Poly(chromotrope fb)-Modified Pencil Graphite Electrode in Vegetables and Fruits

“…It is recommended to take 500–1000 mg/day, which should be included in the daily diet, whereas the overdose may cause headache, inflammation, and damage to the kidney and DNA structure. , Thus, considering both the advantages and disadvantages, monitoring of the Qn level in foodstuffs is very significant. The methods based on spectrophotometry , and chromatography , are widely used for determining Qn. Although these methods yield in terms of sensitivity and selectivity, they employ labor-intensive pretreatment steps, difficult separation procedures, and sophisticated and expensive instruments. , In recent years, electrochemical sensors have come to the forefront for determining some electroactive food and biologically essential substances. − Due to some distinct features of electrochemical methods such as being simple, quick, portable, cost-effective, sensitive, and selective, they have become one of the most encouraging methods for determining Qn. , A wide variety of modified electrodes including single- or multipolymer film-modified electrodes with or without metal nanoparticles, − carbon nanotube-based electrodes with or without polymer films, , molecularly imprinted polymer (MIP)-based electrodes, , and the other ones , have been reported for the determination of Qn, and they are summarized in Table S1.…”

“… 8 , 9 Thus, considering both the advantages and disadvantages, monitoring of the Qn level in foodstuffs is very significant. The methods based on spectrophotometry 10 , 11 and chromatography 12 , 13 are widely used for determining Qn. Although these methods yield in terms of sensitivity and selectivity, they employ labor-intensive pretreatment steps, difficult separation procedures, and sophisticated and expensive instruments.…”