Open AccessComparison of Sample Pretreatment and Analytical Method for Nitrate Determination in Vegetables
Author(s) -
Siriwan Soiklom,
Krittaya Petchpoung,
Wipada Siri-Anusornsak
Publication year - 2021
Publication title -
trends in sciences
Language(s) - English
Resource type - Journals
ISSN - 2774-0226
DOI - 10.48048/tis.2021.19
Subject(s) - chemistry , high performance liquid chromatography , nitrate , chromatography , extraction (chemistry) , quantitative analysis (chemistry) , sample preparation , organic chemistry
Different sample pretreatment extraction techniques and analytical methods are often used for nitrate determination in vegetables; however, the effects of these variables have not been properly examined. Therefore, sample pretreatment (oven-dried and fresh extraction) and nitrate determination methods (colorimetric method (salicylic method (SM)) and high-performance liquid chromatography (HPLC) were compared in Chinese kale (K) and morning glory (M) in this study. Oven-dried and fresh samples (K and M) were extracted by maceration and determined for nitrate content by the SM. As a result, the nitrate contents of both the oven-dried samples were significantly lower than the fresh samples (p < 0.01). A high correlation between the SM and HPLC was observed in 21 oven-dried samples of K and M. The nitrate contents using SM were significantly lower than the HPLC (p < 0.01). Both methods could be used for nitrate analysis in vegetables with an awareness of impurities in the SM.HIGHLIGHTSThe drying process reduced the nitrate contentTemperature effects nitrate contentThe SM demonstrated a lower nitrate content than the HPLC in all the dried vegetable samplesColorimetric by Salicylic acid and HPLC method could be used for nitrate analysis in vegetablesGRAPHICAL ABSTRACT