Wild plants like nutraceuticals sources: INNOVATIVE EXTRACTION, ENCAPSULATION IN W/O AND O/W EMULSION AND ANTIOXIDANT ACTIVITY OF BIOACTIVE PIGMENTS FROM OPUNTIA FICUS INDICA FRUIT

The use and exploitation of plants widely disseminated, which contain bioactive compounds (nutraceuticals), could be the best way to have beneficial effects on health; this also could reduces the environmental impact of transport on long distance of fruits and vegetables, that often involving the loss of nutritional properties of the products. Opuntia ficus-indica is a plant endemic of South America, wild and invasive and it produces an edible fruit, that it grows on the flat pads of the cactus (Fig.1). The fruit is a berry and varying in colour(Fig.2), it develops green (less sweet), becomes orange-yellow and at the end the colour is reddish purple (very sweet). This is reach in betalains, has an application in the low acid foods as natural colorants [1]. It is often used to make candies and jelly or added on drinks such lemonade; its pulp and juice have been used to treat a lot of diseases, such as wounds and inflammations of the digestive and urinary tract in folk medicine. Betalains are water-soluble nitrogenous pigments. They can be divided into two structural groups, the red to red-violet betacyanins (Latin-Beta, beet and Greek-kyanos, blue color) and the yellow betaxanthins (Latin-Beta, beet and Greek-xanthos, yellow) (Fig. 3). The most important source of betanin (Fig. 4) as colouring agent is the red beet (Beta vulgaris subsp. vulgaris) root. 1. Plant Opuntia ficus indica (L.) Mill. 2. Different cultivar of Opuntia ficus-indica [1] Maran J.P. and Manikandan S. (2012). “Response surface modeling and optimization of process parameters for aqueous extraction of pigments from prickly pear (Opuntia ficus-indica) fruit”. Dyes and Pigments, 95: 465-472. [2] Romo-Hualde A.; Yetano-Cunchillos A.I.; González-Ferrero C.; M.J. Sáiz-Abajo; González-Navarro C.J. (2012). Supercritical fluid extraction and microencapsulation of bioactive compounds from red pepper (Capsicum annum L.) by-products. Food Chemistry, 133, 1045–1049. [3] Fernández-López J.A., Almela L. (2001). Application of high-performance liquid chromatography to the characterization of the betalain pigments in prickly pear fruits. Journal of Chromatography, A (913) 415–420. [4] Spizzirri G.U., Cirillo G., Curcio M., Altimari I., Picci N., Iemma F. (2013). “Stabilization of oxidable vitamins by flavonoid-based hydrogels”. Reactive & Functional Polymers, 73: 1030–1037. [5] Abdalla A.E., Roozen J.P. (1999). “Effect of plant extracts on the oxidative stability of sunfower oil and emulsion”. Food Chemistry, 64: 323-329. Wild plants like nutraceuticals sources: INNOVATIVE EXTRACTION, ENCAPSULATION IN W/O AND O/W EMULSION AND ANTIOXIDANT ACTIVITY OF BIOACTIVE PIGMENTS FROM OPUNTIA FICUS INDICA FRUIT In this work has been investigated the possibility of phytochemicals extraction by using the supercritical fluids extraction (SFE) with CO2 from fruits, optimizing the selectivity between them and other substances presents in the vegetal matrix. Supercritical fluid technology is nowadays the most innovative method for preparing bioactive products used as supplements and for the preparation of products for children since the extract is free of solvent traces (the CO2 diffuses at room temperature). The extracts obtained by SFE-CO2 are “Generally Recognized As Safe (GRAS)” by the American Food and Drugs Administration, they can be added to any food [2]. Materials and Methods 5. Collection and peel of Opuntia ficus-indica fruits Opuntia ficus-indica Fruits First Harvesting (November 2012) Second Harvesting (December 2012) Third Harvesting (October 2013) pH 5,68±0,08 5,73±0,04 5,71±0,02 aw 0,928±0,002 0,934±0,005 0,921±0,003 °Bx 15,0±0,1 14,8±0,2 15,2±0,1 UW.b 83,98±0,17 84,37±0,24 83,62±0,08 10. Pulp homogenized from fruit Different solvent extraction Stirred centrifugation filtration 3. The chromophore of betalains (1), the aglycone of most of betacyanins (2), and a proline-containing betaxanthin (3). Spectrophotometric analysis of extracts Betacyanins content was expressed as betanin content (molar mass M = 551,48 g/mol). Wavelength was setted to 527 nm (Fig. 8). HPLC analysis of extract The analysis of all extracts both from solvent extraction and belonged from SFE were carried out by means of HPLC using a Smartline HPLC system (Fig. 9). Chromatographic separation was carried out using a 2,0 mm ID ×150 mm L, with precolumn, C-18 TSKgel ODS-100 V, 21810. Extraction of betalains with supercritical fluids All samples after collection were previously cleaned and peeled, homogenized and frozen; at the time of the analysis; some of them were centrifuged, other partially dried and added with different sand Ottawa and Diatomee, in order to maximize the yields of extraction. The supercritical extractions by CO2 were performed on a Spe-ed SFE 4 extractor (Fig. 7). Flow CO2= 1.5 L/min. • extra virgin olive oil 20w/w% • Tween 60 • buffer solution • CaCl2; • pectin L.M. • ethanol EMU CPFE EMU STD + extract purified of Opuntia ficus-indica EMU STD EMU VIT E EMU STD + Vitamin E • extra virgin olive oil 70w/w% • mono- and diglycerides of • fatty acids • NaCl 0,1 M EMU CPFE EMU STD + extract purified of Opuntia ficus-indica EMU STD EMU VIT E EMU STD + Vitamin E Preparaions of emulsion oil in water (O/W) and water in oil (W/O) Purification of extract (CPFE): the pulp fruit was homogenized, centrifuged and precipitated with acetone; then filtrated with a PTFE siringe. The emulsification was performed using a rotor stator system (Ultra Turrax T 50). Antioxidant activity The antioxidant properties of all emulsions (O/W and W/O), at four different times after preparations (t0= 1 day; t1= 5 days; t2= 10 days; t3= 15 days), were evaluated by measurement of the scavenging activity towards DPPH and ABTS radicals. DPPH Assay (2,2′-diphenyl-1- picrylhydrazyl) λ=517 nm ABTS Assay [2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)] λ=734 nm DPPH and ABTS radicals inhibition in O/W emulsions DPPH and ABTS radicals inhibition in W/O emulsions The homogenised mix (Fig. 10) was prepared to measure the level of acidity of the primary source, brix degrees, water activity and humidity. The measurements of water activity and humidity are a key parameter in the quality control of moisture-sensitive products. Preliminary analysis of pulp 4. Molecular structure of betanin present in red beet root