Immunostimulant activity of aggregates of phenolic compounds and polysaccharides extracted from Jalapeño pepper seeds (Capsicum annuum L.)

Abstract

Thanks to previous studies, the use of enzyme-assisted extraction (EAE) has been demonstrated as one of the best techniques to extract phenolic compounds specifically from pepper seeds. Likewise, the anti-inflammatory activity of these compounds has been studied and how the use of enhancers benefits the extraction and enhances the properties of the extracts. Therefore, the present research corresponds to a continuation of these findings, to be able to demonstrate how ferulic acid as an enhancer is ideal for improving extraction, extracting better quality phenolic compounds, promoting the generation of aggregates to these phenols and also enhancing the properties of the same, also testing how ultrafiltration helps us separate these aggregates to be able to compare their immunostimulant activities and mainly to be able to demonstrate the immunostimulant properties of these extracts. The use of ferulic acid as an enhancer was shown to reduce the amount of total soluble carbohydrates (TSC) and that, when passing through ultrafiltration, it achieved the lowest loss of suspended solids (6%) and the presence of more ppm of phenolic compounds in the samples. With this enhancer, we verified the value of using this phenolic acid in the extraction of phenolic compounds. The findings in particle size gave us the conclusion of the formation of small polyphenols and polysaccharides that manage to pass through the ultrafiltration pores and achieve particle sizes even larger (JPSC = 893.8 nm and JPSF = 1039 nm) than those of the aggregates at times 120 and 180 minutes. The characterization of free phenols served to demonstrate the disappearance of phenolic acids in the filtered compounds and also to quantify vanillin (NF-JPSC = 14.66 – 1.28 μg/g, NF- JPSF = 38.04 – 0 μg/g, F-JPSC = 16.778 – 0 μg/g and F- JPSF = 27.474 – 0 μg/g), which is decreased as the hydrolysis time increases, resulting in the formation of an aggregate of this phenolic compound with sucrose, which is the most abundant sugar in these extracts and which was also characterized and demonstrated that it disappears when it is filtered and only fructose remains as the most abundant sugar. Finally, it was verified that the immunostimulant activity is higher in the concentrated extracts (2x) and in those without filtering, achieving a production of nitric oxide (NOx) of up to 327.76%, and comparing different concentrations of solids in suspension (800, 400, 200 , 100, 50, 25, 12.5 and 6.25 ug/mL) with the minimum concentration being the one with the most immunostimulating activity and also being the least cytotoxic (cell viability = 143.81%) in the 2x sample at 120 minutes of hydrolysis, this being the best of all the samples analyzed.