03034nam a2200349 a 450000100080000000500110000800800410001910000200006024502090008026001310028950000280042052018670044865000200231565000150233565000200235065000230237065000200239365000140241365000230242765000150245065000270246565300190249265300190251165300170253070000250254770000160257270000230258870000160261170000200262770000180264770000190266521710602025-01-28       2024    bl uuuu     u00u1 u    #d1 aSOUZA, P. G. DE  aComparison between methods of extraction and analysis of oxalic acid by flame atomic absorption spectrometry and uv-vis spectrophotometer in purslane leaves (Portulaca Oleracea L.).h[electronic resource]  aIn: SIMPóSIO LATINO AMERICANO DE CIÊNCIA DE ALIMENTOS E NUTRIÇÃO, 15., 2023, Campinas. Anais eletrônicos..., Galoác2024  aSLACAN. Pôster 166099.  aOxalic acid is an antinutrient that can complex with minerals such as calcium, reducing the bioaccessibility of this essential element, in addition to increasing the risk of generating oxalate crystals in the kidneys. Purslane (Portulaca oleracea L.), a Non-conventional edible plants (NCEP), has a high content of oxalic acid. Thus, this study aimed to compare two methods of extraction and analysis for the determination of oxalic acid in lyophilized purslane leaves. For extraction, two methods were used: the first, described by Adeneyi et al., (2009), where 6M HCl was used with heating for 1 hour (M1); and the second, described by Naiki et al., (2014), where 0.25N HCl was used, with heating for 15 min (M2). For both methods, an oxalate precipitation step was performed. The analyzes using the UV-vis spectrophotometer were performed using the KMnO4 oxidation method by oxalic acid, described by Naiki et al., (2014). For analysis by FAAS, the calcium concentration obtained was converted to that of oxalic acid, according to the formula described in the AOAC (1990), with adaptations. The results were expressed on a dry basis. In the spectrophotometer analyses, the leaves presented 27.5 ± 0.96 g/100g for M1 and 12.2 ± 1.1 g/100g for M2, showing a significant difference (p&lt0.05) between the results. In the FAAS analyses, the leaves presented 5.8 ± 0.5 g/100g for M1 and 6.1 g/100g for M2, with no significant difference (p&lt0.05) between the results. The very high levels found for the extraction using 6M HCl for 1 hour may have favored the extraction and precipitation of compounds that were not of interest, causing reactional interferences during the permanganate oxidation step. Extraction with more dilute acid contributes to Green Chemistry and FAAS analysis proved to be adequate for the determination of this antinutrient in purslane.  aCalcium oxalate  aExtraction  aFood technology  aSpectrophotometers  aÁcido Oxálico  aBeldroega  aEspectrofotometria  aExtração  aTecnologia de Alimento  aAcid digestion  aQuímica verde  aSpectrometry1 aSANTOS, A. C. C. dos1 aORLANDO, E.1 aTRINDADE, M. E. F.1 aPALLONE, J.1 aAYRES, E. M. M.1 aROSENTHAL, A.1 aTEODORO, A. J.