Jacinta Collado-González

Sustained deficit irrigation affects the colour and phytochemical characteristics of pomegranate juice

BACKGROUND No information exists on the consequences of water stress on the pomegranate (Punica granatum L.) tree in terms of the quality and health/nutritional properties of its juice. In this study the influence of two different sustained deficit irrigation treatments on the colour, antioxidant activity and total phenolic compound, total anthocyanin, punicalagin and ellagic acid contents of pomegranate juice was assessed. RESULTS Control plants were irrigated at 75% ETo (crop reference evapotranspiration) in order to ensure non-limiting soil water conditions, while others were subjected to sustained deficit irrigation at 43 and 12% ETo throughout the experimental period. Both moderate (43%) and severe (12%) water stress treatments led to pomegranate juices with a more yellowish colour, lower antioxidant activity and lower total phenolic compound, punicalagin and total anthocyanin contents than those from control plants. CONCLUSION Pomegranate juice from trees under sustained deficit irrigation was of lower quality and less healthful than that from trees without water stress. From a nutritional point of view, this means that a reduction in irrigation provides a dramatic decrease in bioactive phenolic compounds, especially anthocyanins and punicalagin, and consequently a lower visual attraction of the juice owing to the weak red colour of the fruit.

New UHPLC-QqQ-MS/MS method for quantitative and qualitative determination of free phytoprostanes in foodstuffs of commercial olive and sunflower oils

In this work, we propose a new quick and accurate analytical method by UHPLC-QqQ-MS/MS which is able to identify free phytoprostanes in olive and refined sunflower oils. The recovery provided high extraction efficiencies ranging from 102.90% to 140.64% using Strata-XAW cartridge. The intra-day and inter-day variations for all target compounds ranged from 2.24% to 13.64% and 0.01% to 13.69%, respectively, and the accuracies for these parameters varied from 80.33% to 119.64% and from 80.34% to 119.90%, respectively. Results obtained reflect that refined sunflower presented more series of phytoprostanes and a 20 and 8-fold higher quantity than two types of olive oil: Extra virgin olive oil and olive oil, (containing half virgin extra olive oil and half refined olive oil). The manufacture process could be the key for the different phytoprostane production since most of the plant oils are subjected to a refining treatment.

Nonenzymatic α-Linolenic Acid Derivatives from the Sea: Macroalgae as Novel Sources of Phytoprostanes.

Phytoprostanes, autoxidation products of α-linolenic acid, have been studied in several plant species, but information regarding the natural occurrence of this large family of biologically active oxidized lipids in macroalgae is still scarce. In this work, the free phytoprostane composition of 24 macroalgae species belonging to Chlorophyta, Phaeophyta, and Rhodophyta was determined through a recently validated UHPLC-QqQ-MS/MS method. The phytoprostane profiles varied greatly among all samples, F1t-phytoprostanes and L1-phytoprostanes being the predominant and minor classes, respectively. No correlation between the amounts of α-linolenic acid in alga material and phytoprostane content was found. Therefore, it was hypothesized that the observed variability could be species-specific or result from interspecific interactions. This study provides new insight about the occurrence of phytoprostanes in macroalgae and opens doors for future exploitation of these marine photosynthetic organisms as sources of potentially bioactive oxylipins, encouraging their incorporation in food products and nutraceutical and pharmaceutical preparations for human health.

Phytochemical and quality attributes of pomegranate fruits for juice consumption as affected by ripening stage and deficit irrigation.

BACKGROUND Pomegranate (PG) is a drought resistant crop, thriving well with scarce water resources. The non-climateric character of PG remarks the importance of determining the optimum harvest time to improve quality and phytochemical properties of PG. RESULTS The influence of two different irrigation treatments on physico-chemical and phytochemical parameters of PG was assessed. Control trees (T0) were over irrigated (105% ETo). From the beginning of the second half of rapid fruit growth period to the last harvest, T1 plants were subjected to sustained deficit irrigation (33% ETo). Results indicated that T1 fruits exhibited a darker and more intense garnet colour than T0 fruits, but deficit irrigation led to a significant decrease in total fruit yield and number of total fruits per tree. T1 fruits showed similar bioactive quality than T0 fruits; however, T1 fruits advanced the optimal harvest time by about 7-8 days with respect to T0 fruits. CONCLUSIONS Late-pomegranate fruits were rich in phytochemicals and could be of great interest to the juice industry. Knowledge of these trends is important, especially to improve PG juice quality and to contribute to the sustainability of PG culture with respect to water, fertiliser and energy saving.

Impact of packaging atmosphere, storage and processing conditions on the generation of phytoprostanes as quality processing compounds in almond kernels.

The thermal processing of almond kernels implies the use of techniques that produce chemical changes such as oxidation. Phytoprostanes (PhytoPs) are considered biomarkers of the oxidative stress in plants. We studied the PhytoP profile in kernels of almond cultivars under different conditions, in relation to packaging, temperature and time of storage and processing. The most abundant PhytoP was the F1t series. The PhytoP levels increased significantly with the time of storage (3 and 6months) and the total PhytoP concentration was higher under air than in a vacuum packaging atmosphere. Storage at 24°C raised the concentrations of individual PhytoPs and the total sum of PhytoPs. The frying and roasting processes led to a strong reduction of the original concentration of most PhytoPs and promoted the synthesis of specific PhytoPs that were not detected in raw kernels and thus could be biomarkers of the degree of oxidative degradation of almonds.

Phytoprostanes in almonds: identification, quantification, and impact of cultivar and type of cultivation

Recently, the relationship between oxidative stress and the phytoprostanes content in plants has been studied. In 1998, it was discovered that phytoprostanes are generated from α-linolenic acid, following a non-enzymatic pathway initiated by enhanced formation of free radicals. Almonds and other nuts have favorable contents of polyunsaturated fatty acids; one of the most-polyunsaturated fatty acids present in plants is α-linolenic acid. This study represents a first approach to the quantitative and qualitative determination of the phytoprostanes profile in 11 almond cultivars under different agronomic conditions (conventional versus ecological, rain-fed versus irrigated). In the kernels have been identified 9-F1t-phytoprostane, 9-epi-9-F1t-phytoprostane, ent-16-epi-16-F1t-phytoprostane, ent-16-F1t-phytoprostane, 9-D1t-phytoprostane, 9-epi-9-D1t-phytoprostane, 16-B1-phytoprostane, and 9-L1-phytoprostane. The total phytoprostane content was in the range of 4.0 to 23.8 ng per 100 g. F1-phytoprostanes predominated and were identified in all almond cultivars. L1-phytoprostanes were minor components while D1-phytoprostanes were only detected in cultivars ‘Colorada’ and ‘Avellanera’. The phytoprostane profile varied greatly depending on the genotype, but was also affected by factors such as the agricultural system (conventional or ecological) and irrigation. The ecological system promoted the synthesis of D1-phytoprostanes. Almonds from rain-fed trees had lower individual and total phytoprostane concentrations than those under irrigation, even though non-irrigation led to the detection of the 16-F1-phytoprostanes. Consequently, irrigation and ecological techniques applied to almonds could be considered as actions to enhance their phytoprostane content and hence their potential beneficial effects on human health.

Water deficit during pit hardening enhances phytoprostanes content, a plant biomarker of oxidative stress, in extra virgin olive oil.

No previous information exists on the effects of water deficit on the phytoprostanes (PhytoPs) content in extra virgin olive oil from fruits of mature olive (Olea europaea L. cv. Cornicabra) trees during pit hardening. PhytoPs profile in extra virgin olive oil was characterized by the presence of 9-F1t-PhytoP, 9-epi-9-F1t-PhytoP, 9-epi-9-D1t-PhytoP, 9-D1t-PhytoP, 16-B1-PhytoP + ent-16-B1-PhytoP, and 9-L1-PhytoP + ent-9-L1-PhytoP. The qualitative and quantitative differences in PhytoPs content with respect to those reported by other authors indicate a decisive effect of cultivar, oil extraction technology, and/or storage conditions prone to autoxidation. The pit hardening period was critical for extra virgin olive oil composition because water deficit enhanced the PhytoPs content, with the concomitant potential beneficial aspects on human health. From a physiological and agronomical point of view, 9-F1t-PhytoP, 9-epi-9-F1t-PhytoP, and 16-B1-PhytoP + ent-16-B1-PhytoP could be considered as early candidate biomarkers of water stress in olive tree.

Quantification of phytoprostanes – bioactive oxylipins – and phenolic compounds of Passiflora edulis Sims shell using UHPLC-QqQ-MS/MS and LC-IT-DAD-MS/MS

The genus Passiflora, comprising about 500 species, is the largest in the Passion flower family. Passiflora edulis Sims f. edulis (gulupa) is one of the most important fruits cultivated in Colombia. In recent years and due to its organoleptic and bioactive properties, its exports have significantly increased. In this work, six new bioactive oxylipins -phytoprostanes - were detected in gulupa shell by a UHPLC-QqQ-MS/MS method: F1t-phytoprostanes and D1t-phytoprostanes were the predominant and minor classes, respectively. Moreover, the polyphenol profile of the shell was investigated and we were able to detect and quantify phenolic compounds that have not been described previously, like luteolin-8-C-(2-O-rhamnosyl)hexoside and quercetin-3-O-(6″-acetyl)glucosyl-2″-sinapic acid. Consequently, this study provides new insights into the importance of gulupa shell as a valuable option in the design of new beverages rich in antioxidant phytochemicals, as part of a well-balanced diet, and in the process and quality control of such products.

Effect of the season on the free phytoprostane content in Cornicabra extra virgin olive oil from deficit‐irrigated olive trees

BACKGROUND The effect of regulated deficit irrigation (RDI) on the phytoprostane (PhytoP) content in extra virgin olive (Olea europaea L., cv. Cornicabra) oil (EVOO) was studied. During the 2012 and 2013 seasons, T0 plants were irrigated at 100% ETc, while T1 and T2 plants were irrigated avoiding water deficit during phases I and III of fruit growth and saving water during the non-critical phenological period of pit hardening (phase II), developing a more severe water deficit in T2 plants. In 2013, a fourth treatment (T3) was also performed, which was similar to T2 except that water saving was from the beginning of phase II to 15 days after the end of phase II. RESULTS 9-F1t -PhytoP, 9-epi-9-F1t -PhytoP, 9-epi-9-D1t -PhytoP, 9-D1t -PhytoP, 16-B1 -PhytoP and 9-L1 -PhytoP were present in Cornicabra EVOO, and their contents increased in the EVOO from RDI plants. CONCLUSION Deficit irrigation during pit hardening or for a further period of 2 weeks thereafter to increase irrigation water saving is clearly critical for EVOO composition because of the enhancement of free PhytoPs, which have potential beneficial effects on human health. The response of individual free PhytoPs to changes in plant water status was not as perceptible as expected, preventing their use as biomarkers of water stress.

Fruit Response to Water-Scarcity Scenarios. Water Relations and Biochemical Changes

Abstract The aim of this chapter is to give a general idea of the fruit response to water-scarcity conditions, paying special attention to fruit water relations modification and fruit composition changes, which are key for fruit quality. The strengths and weaknesses of fruit water relations measurement parameters are discussed. The incidence of some pre- and postharvest fruit physiological disorders related to water stress (cracking, creasing, pitting, splitting, and watercore) was also considered. Current knowledge of water flow in developing fruits, fruit water relations under drought, and the effect of water deficit on fruit quality characteristics, mainly those related to human health, are discussed and new research objectives are proposed. In addition, the need to differentiate the products from deficit-irrigated trees (hydroSOS) from any others on the market is discussed.