Caracterização química e bioativa de diferentes flores do género Impatiens e estudo do seu potencial uso na indústria alimentar

Abstract

Non-Conventional Food Plants (PANCs) are plants considered to be potentially suitable for human consumption, which generally grow spontaneously in the environment under previous conditions of cultivation and / or treatment. Although many of these plants are available in abundance in nature, they are still little known by the population that classifies them as "weeds". Within the universe of PANCs, edible flowers stand out as a source of nutrients used since ancient times, normally classified as excellent sources of substances beneficial to human health. Flowers of the genus Impatiens are widely used for ornamental purposes in landscaping projects, and although they are edible, their use in food applications is not yet common practice. The attractive colors characteristic of these flowers has aroused great interest on the part of the food industry that seeks natural sources of coloring ingredients. The association of adverse effects with the excessive consumption of some artificial additives has been affecting the choices of consumers who currently demand healthier and more natural products. In this way, several plant matrices have been explored. In this sense, this work aimed to characterize the petals of two species of Impatiens, I. balsamina and I. walleriana, in the pink and orange varieties of both. The phenolic compounds were determined by high performance liquid chromatography coupled to a diode detector and mass spectrometry detector (HPLC-DAD-ESI / MS) and different bioactivities (antioxidant, antimicrobial, anti-inflammatory and cytotoxicity activities) were analyzed. All samples studied showed significant amounts of phenolic compounds, especially phenolic acids and flavonoids. The species I. balsamina showed a greater variety of phenolic compounds; however, both pink varieties had the greatest amount of both anthocyanin and non-anthocyanin compounds. This result is in line with those obtained in bioactivities, in which I. balsamina pink stood out as the extract with the most promising bioactive potential. Both varieties of I. balsamina were chemically and nutritionally characterized following official AOAC analysis methodologies. The flowers had a high water content (90%) and low amounts of macronutrients and ash. The orange variety had higher levels of fat (0.12 ± 0.01 g / 100 g fw) and proteins (0.33 ± 0.01g / 100 g fw), while for the pink variety it had higher values of carbohydrates (4.76 ± 0.02 g / 100 g fw) and energy value (21.145 ± 0.003 kcal / 100 g fw). Regarding the fatty acid profile, the orange variety had a higher content of saturated fatty acids (44.9 ± 0.5%) while the pink variety showed a predominance of polyunsaturated fatty acids (52.7 ± 0.5%), in which the stearic acids (C18: 0), linoleic (C18:2n6) and γ-linoleic (C18:3n6) the majority. In turn, succinic acid emerged as the major organic acid for both varieties. Given the possible of the possible industrial application as natural coloring ingredients, the extract of I. balsamina rose petals was selected for incorporation into “bombocas” filling, comparing with traditional “bombocas” (white filling) and pink filling (prepared using commercial gelatine of strawberry with dye E163). The extract of the flowers of I. balsamina showed remarkable results, being able to provide a reasonable increase in the protein content of the final product and enhance its color. Although the color conferred by the extract is a little lighter than that presented by strawberry gelatin, it seems to suggest a more natural aspect that, in addition to the functional activity conferred, meets the current expectations of consumers, presenting potential for application in the food industry.