María de Cortes Sánchez-Mata

Comparison of high-performance liquid chromatography and spectrofluorimetry for vitamin C analysis of green beans (Phaseolus vulgaris L.).

Abstract A spectrofluorimetric method and a chromatographic method [high-performance liquid chromatography – ultraviolet (HPLC-UV) detection] were compared for vitamin C analysis of green beans. For HPLC-UV, the determination was performed before [ascorbic acid (AA)] and after reduction with dithiothreitol [AA + dehydroascorbic acid (DHAA)]; for spectrofluorimetry, DHAA was determined after oxidation with activated charcoal. The fluorimetric determination of DHAA before oxidation was also carried out, and showed good precision but poor accuracy (very high recovery percentages). HPLC-UV showed better linearity and sensitivity, while spectrofluorimetry was more precise. Both methods were suitable for green bean samples, and the choice of which one to use depends on the particular interest of the analysis: spectrofluorimetry may be preferable when the total content of vitamin C is required, but not for individual analysis of each form. HPLC-UV is more suitable when the interest of the analysis is the ascorbic acid form as a deterioration index of vegetable products.

Mineral and Trace Elements Content in 30 Accessions of Tomato Fruits (Solanum lycopersicum L.,) and Wild Relatives (Solanum pimpinellifolium L., Solanum cheesmaniae L. Riley, and Solanum habrochaites S. Knapp & D.M. Spooner)

Tomato quality and its potential health benefits are directly related to its chemical composition. The characterization of nutritional properties of Solanum germplasm is essential to choose suitable donor parents for breeding programs. In this sense, wild species could be very useful for tomato fruit quality genetic improvement. With this objective, in this work, we characterize micronutrients content in Eulycopersicon germplasm (20 cultivars of S. lycopersicum L. and 10 accessions of wild relatives) analyzing mineral (Na, K, Ca, Mg) and trace elements (Cu, Fe, Zn, Mn) and applying multidimensional analysis (principal component and cluster analysis). The classification obtained and the comparison of cultivars performance showed that wild accessions belonging to S. cheesmaniae (L. Riley), S. pimpinellifolium L., and S. habrochaites S. Knapp & D.M. Spooner can be of great usefulness in breeding programs to improve mineral content characteristics of conventional S. lycopersicum varieties due to its higher mineral content.

Carotenoid content of wild edible young shoots traditionally consumed in Spain (Asparagus acutifolius L., Humulus lupulus L., Bryonia dioica Jacq. and Tamus communis L.)

BACKGROUND Wild vegetables have traditionally been consumed as part of the Mediterranean diet, being valuable sources of nutrients and bioactive compounds. The objective of this work was to analyse the carotenoid content of the edible young shoots of four species (Asparagus acutifolius L., Humulus lupulus L., Bryonia dioica Jacq. and Tamus communis L.) as part of a wider study on the characterisation of the nutritional composition of wild edible plants commonly consumed in Spain. Samples were gathered from two locations in Central Spain for two consecutive years. RESULTS Lutein, β-carotene, neoxanthin and violaxanthin were quantified by high-performance liquid chromatography with a photodiode array detector. Median concentration ranges (μg g(-1) edible wet weight) were: β-carotene, 3.39-6.69, lutein, 5.44–19.13;neoxanthin, 5.17-17.37; and violaxanthin, 2.08-8.93. The highest carotenoid content was that of B. dioica (59.01 μg g(-1)) and the lowest was found in A. acutifolius (17.58 μg g(-1)) [corrected]. CONCLUSION Our results show that these wild young shoots are richer sources of carotenoids than many of the commercially available leafy vegetables.

Lycopene: A Review of Chemical and Biological Activity Related to Beneficial Health Effects

Abstract This work focuses on the developments related to lycopene, a natural carotenoid and bioactive compound, particularly with reference to its chemistry and biological activity and its potential health effects. The formation of free radicals or other compounds in the body that are able to oxidize lipids, proteins, and DNA (also known as oxidative stress) is one of the major risk factors for chronic diseases. There is considerable evidence that lycopene has a protective effect against cardiovascular disease, hypertension, atherosclerosis, skin damage, and certain types of cancer such as prostate, breast, lung, and others. Because of this, the presence of lycopene in the diet is considered to be of great value. Dietary lycopene may increase the lycopene level in the body and act as an antioxidant. It may trap reactive oxygen species resulting in an increase in the overall antioxidant potential or a reduction in the oxidative damage to lipids (lipoproteins, membrane lipids), proteins (important enzymes), and DNA (genetic material), thereby lowering the oxidative stress. Alternatively, the increase in serum lycopene level may regulate gene functions, with the enhancement of intercellular communication (responsible for cell growth), modulating hormonal and immune response, regulating metabolism, and thus lowering the risk of chronic diseases. These mechanisms may also be interrelated and may act simultaneously to provide health benefits. Lycopene is quickly absorbed from different food sources (mainly tomato products) and distributed to corporal tissues where it maintains its antioxidant properties. This absorption varies depending on various factors such as food source, food processing, and other components in the diet. The human body is unable to synthesize carotenoids, such as lycopene, so a suitable diet intake is necessary to reach the adequate levels. In this review, the new developments in lycopene analysis by spectroscopic and chromatographic techniques along with mathematical modeling are also considered. These advances have made it possible to evaluate and determine the biological activity of lycopene in natural products. All this knowledge about the chemistry and biological activity of lycopene will be very helpful for the food industry, providing new opportunities in the field of food product development.

Ethnobotanical and Food Composition Monographs of Selected Mediterranean Wild Edible Plants

This chapter presents 38 monographs about 41 selected wild edible plants traditionally consumed in different countries of the Mediterranean basin: Allium ampeloprasum, Anchusa azurea, Apium nodiflorum, Arbutus unedo, Asparagus acutifolius, Beta maritima, Borago officinalis, Bryonia dioica, Capsella bursa-pastoris, Chenopodium album, Chondrilla juncea, Cichorium intybus, Crataegus monogyna, Crithmum maritimum, Eruca vesicaria, Foeniculum vulgare, Humulus lupulus, Malva sylvestris, Montia fontana, Myrtus communis, Papaver rhoeas, Plantago lanceolata, P. major, Portulaca oleracea, Prunus spinosa, Rorippa nasturtium-aquaticum, Rubus ulmifolius, Rumex acetosa, R. papillaris, R. pulcher, Scolymus hispanicus, Silene vulgaris, Silybum marianum, Smilax aspera, Sonchus asper, S. oleraceus, Tamus communis, Taraxacum officinale, T. obovatum, Urtica dioica, and Ziziphus lotus. These monographs have two parts. The first part consists of a botanical and graphical description of the species and a resume of ethnobotanical data registered in the Mediterranean countries for this edible plant. The second part supplies food composition data for each species, covering the main constituents, vitamins and other bioactive compounds as well as fatty acids profile, based on scientific literature data.

The Contribution of Wild Plants to Dietary Intakes of Micronutrients (I): Vitamins

Scientific literature data about contents of vitamins in wild vegetables and fruits traditionally eaten in Mediterranean regions are related to the most accepted recommendations for vitamins intake. Even taking into account the natural variability, which is expected to occur in biological tissues, there is sufficient evidence to consider many of these edible wild species as interesting vitamin sources. For example, a portion of 100 g of many of them may provide, in many cases, the total amount of vitamins B9 (folates), C, and/or K daily needed by adults. In other cases, 30 % of daily recommendations of vitamins A and E could also be provided.

The Contribution of Wild Plants to Dietary Intakes of Micronutrients (II): Mineral Elements

Many wild greens and fruits are valuable contributors to dietary mineral intakes. They may provide Ca, Mg, Fe and Mn amounts that in some cases may reach 50 % of the daily requirements recommended by different institutions, and K and Cu levels reaching 30 % of the recommendations.