Carotenoid and Carotenoid Ester Profile and Their Deposition in Plastids in Fruits of New Papaya (Carica papaya L.) Varieties from the Canary Islands

Abstract

The carotenoid profile of non-saponified and saponified extracts of different tissues (pulp and peel) of fruits of three new papaya varieties, Sweet Mary, Alicia, and Eksotika, was characterized for the first time, and almost all carotenoid compounds were quantified. Carotenoids and carotenoid esters were analyzed and characterized using HPLC–photo diode array (PDA–MS with atmospheric pressure chemical ionization with positive ion mode (APCI+) with a C30 reversed-phase column. The carotenoid deposition in collenchyma and chlorenchyma cells of papaya pulp and peel tissues was assessed by optical microscopy, confocal laser scanning microscopy, and transmission electron microscopy. The most abundant carotenoids in the fruit of the three papaya varieties (pulp and peel) were (all-E)-lycopene (230.0–421.2 µg/100 g fresh weight), (all-E)-β-carotene (120.3–233.2 µg/100 g fresh weight), and (all-E)-β-cryptoxanthin laurate (74.4–223.2 µg/100 g fresh weight. Moreover, high concentrations of (all-E)-lutein (922.5–1381.1 µg/100 g fresh weight) and its esters, such as (all-E)-lutein-3-O-myristate and (all-E)-lutein dimyristate, were found in peel extracts. The optical microscopy study of papaya pulps showed that carotenoid deposition in all papaya varieties, including Maradol, was mainly localized close to the cell walls, showing the presence of some crystalloids and round-shaped structures, with different sizes and distribution due to the different carotenoid content among varieties. No crystalloids or globular depositions were found in any of the peel sections, and no remarkable differences were found in the papaya peel microstructure of the different papaya varieties.

Effect of Ultrasound-Assisted Extraction of Carotenoids from Papaya (Carica papaya L. cv. Sweet Mary) Using Vegetable Oils

“…The complete characterization of carotenoids and carotenoids esters from papaya cv. Sweet Mary tissues (pulp and peel) using the convectional extraction has been previously reported by Lara-Abia et al [2], and this information was the guide to identify the carotenoids and carotenoids esters extracted to the vegetable oils. The chromatographic identification (retention time (min), compound identity, absorption maxima (nm), %III/II, %A b /A ii , [M + H] + (m/z), and MS fragmentation pattern (m/z) of each lipophilic carotenoid compound found in oil vegetable extracts is described in Table 1.…”

“…The chromatographic profiles of the papaya pulp and peel extracts obtained from the standard (control) untreated and UAE extracts did not show any differences in carotenoid profiles between using soybean oil and sunflower oil (Figure S1, Supplementary material). In Figure S1, the chromatograms corresponded to the carotenoid profile of UAE extracts obtained at the optimum conditions (high yields) and to the control extracts obtained by the standard protocol for carotenoid analysis [2]. No degradation of carotenoids or carotenoid esters was detected in the UAE extracts, thus carotenoid profiles remained unchanged throughout the extraction process.…”

“…Sweet Mary is an interesting variety to investigate due to its high concentration in bioactive compounds and to promote national production and commercialization. Currently, Spain is the largest papaya producer in Europe (annual production of 15,000 tons, approximately) and the Canary Islands are Molecules 2022, 27, 638 2 of 18 the largest producers (farms totaling 300 ha) [2,3]. Papaya is a climacteric fruit, in which maturation occurs very sudden after recollection.…”

Effect of High Hydrostatic Pressure on the Extractability and Bioaccessibility of Carotenoids and Their Esters from Papaya (Carica papaya L.) and Its Impact on Tissue Microstructure

“…The identification and quantification of carotenoids and carotenoid esters on the pulp tissue of the Sweet Mary, Alicia and Eksotika papaya varieties has been previously reported by Lara-Abia et al [13]. The results reported in the mentioned investigation were considered as the control data for this study due to the simultaneity of the two studies.…”

“…The promotion of this fruit and its nutritional benefits are, therefore, key to support the import and demand of papaya fruits, especially in the European Union. In Spain, the introduction in the market of three new papaya varieties, i.e., Sweet Mary, Alicia and Eksotika, cultivated in the Canary Islands, has caught the interest in our research group due to their interesting carotenoid profile based on a recent study reported by Lara-Abia et al [13], where the utilization of these new varieties as a source of bioactive compounds is a real possibility for industrial applications.…”