Glucosinolates and fatty acid, sterol, and tocopherol composition of seed oils from Capparis spinosa Var. spinosa and Capparis ovata Desf. Var. canescens (Coss.) Heywood

Seed oils of 11 samples of Capparis ovata and Capparis spinosa from different locations in Turkey were characterized with regard to the composition of fatty acids, tocopherols, and sterols as well as the content of glucosinolates. The oil content of the seeds ranged from 27.3 to 37.6 g/100 g (C. spinosa) and from 14.6 to 38.0 g/100 g (C. ovata). The dominating fatty acid of both species was linoleic acid, which accounted for 26.9-55.3% in C. ovata seed oils and for 24.6-50.5% in C. spinosa seed oils. Oleic acid and its isomer, vaccenic acid, were both found in the seed oils in concentrations between 10 and 30%, respectively. The seed oils of both species were rich in tocopherols with the following composition: gamma-tocopherol, 124.3-1944.9 mg/100 g; delta-tocopherol, 2.7-269.5 mg/100 g; and alpha-tocopherol, 0.6-13.8 mg/100 g. The concentration of total sterols ranged from 4875.5 to 12189.1 mg/kg (C. ovata) and from 4961.8 to 10009.1 mg/kg (C. spinosa), respectively. In addition to sitosterol, which amounted to approximately 60% of the total amount of sterols, campesterol and stigmasterol accounted for 16 and 10% of the total sterols, respectively. The seed oils showed remarkably high contents of Delta5-avenasterol (between 138.8 and 599.4 mg/kg). The total content of glucosinolates of C. ovata and C. spinosa samples was determined as 34.5-84.6 micromol/g for C. ovata and 42.6-88.9 micromol/g for C. spinosa, respectively, on a dry weight basis, with >95% as glucocapperin.     

Phytosterol composition of nuts and seeds commonly consumed in the United States

Phytosterols were quantified in nuts and seeds commonly consumed in the United States. Total lipid extracts were subjected to acid hydrolysis and then alkaline saponfication, and free sterols were analyzed as trimethylsilyl derivatives by capillary GC-FID and GC-MS. Delta5-Avenasterol was quantified after alkaline saponification plus direct analysis of the glucoside. Sesame seed and wheat germ had the highest total phytosterol content (400-413 mg/100 g) and Brazil nuts the lowest (95 mg/100 g). Of the products typically consumed as snack foods, pistachio and sunflower kernel were richest in phytosterols (270-289 mg/100 g). beta-Sitosterol, Delta5-avenasterol, and campesterol were predominant. Campestanol ranged from 1.0 to 12.7 mg/100 g. Only 13 mg/100 g beta-sitosterol was found in pumpkin seed kernel, although total sterol content was high (265 mg/100 g). Phytosterol concentrations were greater than reported in existing food composition databases, probably due to the inclusion of steryl glycosides, which represent a significant portion of total sterols in nuts and seeds.     

Hydroponic cultivation improves the nutritional quality of soybean and its products

Hydroponic cultivation allows the control of environmental conditions, saves irrigation water, increases productivity, and prevents plant infections. The use of this technique for large commodities such as soybean is not a relevant issue on fertile soils, but hydroponic soybean cultivation could provide proteins and oil in adverse environmental conditions. In this paper, the compositions of four cultivars of soybean seeds and their derivates, soy milk and okara, grown hydroponically were compared to that of the same cultivar obtained from soil cultivation in an open field. Besides proximal composition, the concentrations of phytic acid and isoflavones were monitored in the seeds, soy milk, and okara. Results demonstrated that, independent from the cultivar, hydroponic compared to soil cultivation promoted the accumulation of fats (from 17.37 to 21.94 g/100 g dry matter) and total dietary fiber (from 21.67 to 28.46 g/100 g dry matter) and reduced isoflavones concentration (from 17.04 to 7.66 mg/kg dry matter), whereas protein concentration was unaffected. The differences found in seed composition were confirmed in the respective okara products, but the effect of cultivation system was not significant looking at the soy milk composition. Data showed that hydroponic cultivation improved the nutritional quality of soybean seeds with regard to fats and dietary fiber. They also suggest that specific cultivars should be selected to obtain the desired nutritional features of the soybean raw material depending on its final destination.     

芭蕉芋干物质及矿质营养元素累积与分配特征研究

以3 个芭蕉芋栽培品种为试材,研究了芭蕉芋发棵结芋期和子芋完熟期生物量的构成特点及各器官矿质元素含量、 积累和分配规律,以期为芭蕉芋科学管理和合理施肥提供依据。结果表明,发棵结芋期,芭蕉芋干物质量为54.99~62.21g/plant,叶片是干物质主要的分配器官; 子芋完熟期,芭蕉芋的干物质量是发棵结芋期的 4 倍多,根茎为干物质的主要分配器官。发棵结芋期,3 个芭蕉芋品种平均每株累积吸收N 497.4mg~598.8mg、 P 128.7mg~223.1mg、 K 2021.2.mg~2450.3mg、 Ca 496.0 mg~577.3 mg、 Mg 526.7 mg~804.5 mg,氮以叶片中含量最高,磷、 钾和镁以茎中含量最高,根系内钙含量最高; 子芋完熟期,芭蕉芋平均每株累积N 1116.2~1210.8mg、 P 852.6~907.5mg、 K 4528.9~5055.2 mg、 Ca 919.2~991.7mg、 Mg 888.2~1369.0 mg,氮以叶片含量最高,钾含量以根系最高,磷含量以茎、 叶中最高,根茎内镁含量高。生育期内构建相同生物量,Xingyu-1需要的 K、 Ca 和 Mg 比其他 2个品种多,N和P与其他2个品种相当,但Xingyu-1 的根茎干物质分配率高,生产相同质量的干根茎,Xingyu-1 需要的N、 P、 K 低于其他 2 个品种。     

Distribution of free amino acids, flavonoids, total phenolics, and antioxidative activities of Jujube (Ziziphus jujuba) fruits and seeds harvested from plants grown in Korea

Fruit pulp and seeds from the jujube plant possess nutritional and medicinal properties. The bioactive components have been shown to vary both with cultivar and with growing conditions. Most studies report the components of varieties from China. We measured free amino acid, individual phenolic, and total phenolic content, and antioxidative activities in three jujube fruit pulp extracts from Boeun-deachu, Mechu, and Sanzoin cultivars and two seed extracts (Mechu and Sanzoin) from plants grown in Korea. In g/100 g dry weight, total free amino acid content measured by ion-exchange chromatography ranged from 5.2 to 9.8 in the pulp and from 4.0 to 5.3 in the seed. Total phenolic content measured by Folin-Ciocalteu ranged from 1.1 to 2.4 in the pulp and from 3.6 to 4.6 in the seed. Flavonoids were measured by HPLC and ranged from 0.7 to 1.8 in the pulp and from 3.2 to 4.0 in the seed. Flavonoids were identified by HPLC elution position and UV/vis and mass spectra. Fruits contained the following flavonoids: procyanidin B2, epicatechin, quercetin-3-O-rutinoside (Q-3-R), quercetin-3-O-galactoside (Q-3-G), kaempferol-glucosyl-rhamnoside (K-G-R), and two unidentified compounds. Seeds contained the following flavonoids: saponarin, spinosin, vitexin, swertish, 6'-hydroxybenzoylspinosin (6'-HBS), 6'-feruloylspinosin (6'-FS), and one unidentified substance. Dimensions and weights of the fresh fruit samples affected phenolic content. The distribution of the individual flavonoids among the different samples varied widely. Data determined by the FRAP antioxidative assay were well correlated with total phenolic content. In a departure from other studies, data from the DPPH free radical assay were not correlated with FRAP or with any of the measured compositional parameters. Because individual jujube flavonoids are reported to exhibit different health-promoting effects, knowledge of the composition and concentration of bioactive compounds of jujube products can benefit consumers.     

Variability in Elemental Accumulations Among Leafy Brassica oleracea Cultivars and Selections

Abstract

The vegetable brassicas are consumed in part for their nutritional values of calcium (Ca), magnesium (Mg), potassium (K), iron (Fe), and zinc (Zn). However, information on the genetic variability of elemental accumulation within kale and collards (Brassica oleracea L. var. acephala DC) is limited. Therefore, 22 kale and collard cultivars and selections suitable for the northeastern United States were field grown under similar fertility regimes over two years and evaluated for elemental accumulation. Leaf tissues were analyzed using inductively coupled argon plasma–atomic emission spectrometry. Significant variability among cultivars and selections was observed for tissue Ca, Mg, K, Fe, and Zn. On average, a two-fold difference in elemental accumulation among the cultivars and selections was measured. Tissue Ca levels ranged from 1.2 (“Crimson Garden”) to 3.1% (“NZ Thousand Head”), tissue Mg ranged from 0.3 (“Crimson Garden”) to 0.6% (“NZ Thousand Head”), tissue K ranged from 2.1 (“NZ Thousand Head”) to 3.5% (30665-96G11), tissue Fe ranged from 53.1 (“Winterbor F1”) to 114.2 mg/kg (“Giant Jersey Kale”), and tissue Zn ranged from 29.1 (“Shetland”) to 71.9 mg/kg (“Redbor F1”). Significant year-to-year variability occurred for Ca, Mg, Fe, and Zn accumulation. Despite these yearly changes, ranking of the cultivars and selections for elemental accumulation, as determined by Spearman's rank correlation coefficient, did not change from year 1 to year 2. Overall, the cultivar with the highest elemental leaf accumulation was “Redbor F1”. Information on genotypic variability for elemental accumulation may be important for producers and consumers looking to select kale and collards with higher nutritional levels of beneficial dietary elements.     

Fagopyritols, D-chiro-inositol, and other soluble carbohydrates in buckwheat seed milling fractions

Fagopyritols are mono-, di-, and trigalactosyl derivatives of D-chiro-inositol that accumulate in seeds of common buckwheat (Fagopyrum esculentum Moench) and may be important for seed maturation and as a dietary supplement. Fagopyritols and other soluble carbohydrates were assayed in mature groats and 11 milling fractions of common buckwheat seed. Because fagopyritols are in embryo and aleurone tissues, differences in fagopyritol concentrations reflect varying proportions of these tissues in each milling fraction. Bran milling fractions contained 6.4 g of total soluble carbohydrates per 100 g of dry weight, 55% of which was sucrose and 40% fagopyritols. Flour milling fractions had reduced fagopyritol concentration [0.7 g/100 g of dry weight total fagopyritols in the dark (Supreme) flour and 0.3 g/100 g in the light (Fancy) flours]. Fagopyritol B1 was 70% of total fagopyritols in all milling fractions. Fagopyritols were 40% of total soluble carbohydrates in groats of two cultivars of common buckwheat but 21% in groats of tartary buckwheat [Fagopyrum tataricum (L.) Gaertn.], probably a reflection of environment and genetics. A rhamnoglucoside present in tartary buckwheat was not detected in common buckwheat.     

Assessment of cyanogenic potential,nitrate and nitrite contents,and trypsin inhibitor activity of some Nigerian legumes

Edible seeds of seven varieties of legumes commonly consumed by Nigerians in large quantities were evaluated for total protein, cyanogens, nitrate and nitrite contents, and trypsin inhibitor activity using chemical, biochemical, enzymatic, and spectrophotometric methods. All analyzed samples contained cyanogen and nitrate with levels ranging from 5.88 +/- 0.26 to 28.55 +/- 1.32 mg/100 g of DM and from 49.64 +/- 4.60 to 239.42 +/- 7.20 mg/100 g of DM, respectively. Only three of the varieties contained detectable levels of nitrite, which varied from 0.54 +/- 0.01 to 3.19 +/- 0.2 mg/100 g of DM. Trypsin inhibitor activity was detected in all of the samples, ranging from 7.75 to 100.75 micromol/min/mg of protein. Total protein content of the legumes ranged from 17.8 to 28% on a dry weight basis. There was a positive correlation (r = 0.71) between the cyanogenic potential and the nitrate content of the dry seeds. Processing reduced about 78.6-88.8% and 71.0-89.5% of total cyanogen and nitrate contents of the seeds, respectively. Following administration of 5.0-15 mg of NO3 to rats by stomach intubation, analysis of their 24, 48, and 72 h urine showed that only 40% of the administered nitrate appeared in the urine unmetabolized. Processing was shown to drastically reduce these antinutritional factors to very low levels. The health implications of these findings are discussed.     

The hypocholesterolemic activity of transgenic rice seed accumulating lactostatin, a bioactive peptide derived from bovine milk β-lactoglobulin

Lactostatin is a novel pentapeptide (IIAEK) derived from bovine milk β-lactoglobulin with greater hypocholesterolemic activity than β-sitosterol, the drug commonly used to treat hypercholesterolemia. We developed transgenic rice expressing lactostatin as a fusion protein with seed storage protein (SSP) glutelins under the control of three different endosperm-specific promoters. Lactostatin accumulated in transgenic rice seed at approximately 1.6 mg/g seeds (dry seeds) without any apparent influence on seed traits such as endogenous SSP expression levels or alterations in the intracellular structures of endosperm cells. Short-term (three day) oral administration of the glutelin fraction containing lactostatin (namely three times of 300 mg/kg body weight/day) extracted from transgenic rice seeds resulted in hypocholesterolemic activity in rats; namely, the serum low-density-lipoprotein (LDL) cholesterol level was significantly reduced accompanied by a significant increase in beneficial serum high-density-lipoprotein (HDL) cholesterol.     

Calcium Nutrition of Peanut Grown in Solution Culture. II. Pod-zone and Tissue Calcium Requirements for Fruiting of a Virginia and a Spanish Peanut

Virginia peanut types need more calcium (Ca) in the soil than Spanish types for high pod yield, but their actual soil solution and fruit tissue Ca requirements have not been well defined. A split root and pod solution culture technique was used to examine the effects of Ca concentration on fruiting of one Virginia cv. ‘Virginia Bunch 1’ and one Spanish peanut cv. ‘TMV-2’. Plants were grown in complete nutrient solution (root zone) containing 100 μM Ca, and six treatments imposed in which the pod zone solution Ca was controlled at 0 to 2500 μM. ‘TMV-2’ produced some mature seeds with no Ca added to the pod zone solution and 81% of maximum seed dry matter at 5 μM Ca, a concentration at which its pod dry matter production was close to maximum. In contrast, ‘Virginia Bunch 1’ produced no pods with no Ca added to the pod zone and only 28% of maximum pod dry matter at 5 μM Ca. ‘TMV-2’ required 6 and 21 μM Ca in the pod zone solution for 95% of maximum pod and seed production, respectively. The corresponding solution concentrations for ‘Virginia Bunch 1’ were 35 and 50 μM Ca. The seed dry matter production of ‘Virginia Bunch 1’ decreased with ≥112 μM Ca in the pod zone solution due to a decrease in individual seed mass, but there was no depression in the case of ‘TMV-2’ up to the highest pod zone solution concentration of 2500 μM Ca studied. The Ca concentration in pod walls and seeds of both cultivars increased with increase in Ca up to 500 μM in the pod zone, the effect being greater in ‘TMV-2’. However, the seed production of both cultivars was maximized at approximately the same seed Ca concentration of 0.04%. The results of this study have shown that the Spanish peanut cv. ‘TMV-2’ and the Virginia peanut cv. ‘Virginia Bunch 1’ have a similar tissue Ca requirement for seed growth despite the higher pod zone Ca requirement of ‘Virginia Bunch 1’.     

HPLC analysis of sesaminol glucosides in sesame seeds

An HPLC method was developed and validated for the quantification of sesaminol triglucoside and a sesaminol diglucoside in sesame seeds. These two lignans were isolated, and their structures were characterized by mass and nuclear magnetic resonance spectroscopy. Defatted sesame flour was extracted first with 85% ethanol for 5 h followed by 70% ethanol for 10 h at room temperature using naringenin as internal standard. Analysis of 65 different samples of sesame seeds indicated that the content of sesaminol triglucoside ranged from 36 to 1560 mg/100 g of seed (mean 637 +/- 312) and that of sesaminol diglucoside ranged from 0 to 493 mg/100 g of seed (mean 75 +/- 95). No significant difference was found between sesaminol glucoside contents in black and white seeds.     

Zinc Biofortification in Sixty Groundnut Cultivars Through Foliar Application of Zinc Sulphate

A field experiment with 60 groundnut cultivars, in a calcareous soil having 1.20 mg kg^?1 available zinc (Zn), foliar application of 0.2% aqueous solution of zinc sulphate thrice at 40, 55 and 70 days at 500, 500 and 1000 L ha^?1, respectively, increased the number of pods, pod yield, shelling and 100 seed mass and seed zinc (Zn) content, significantly. The seeds Zn content in groundnut cultivars ranged 38–70 mg kg^?1 with an average of 48 mg kg^?1 without Zn and 58 mg kg^?1 with Zn. Foliar Zn application increased 22% Zn in seed. This increase was more than 10% in 48 out of 60 cultivars. The cultivars GG 7, GG 20, Tirupati 4, DH 8, JSP 19, TKG 19 A, CSMG 884 and S 206 showed > 50 mg kg^?1 Zn, > 10% increase in seed Zn with Zn application and > 250 g m^?2 pod yield.     

Influence of cultivar on quality parameters and chemical composition of strawberry fruits grown in Brazil

Six strawberry cultivars grown on the same commercial plantation in Brazil were evaluated for their chemical composition and quality attributes at the ripe stage. The profiles of the main soluble sugars, ascorbic acid, and anthocyanins were also obtained during the developmental stages. Results showed significant differences among cultivars in all of the investigated parameters. Cv. Campineiro showed an average value for texture of 0.63 N, half the value found for cv. Oso Grande. Anthocyanin content ranged from 13 (cv. Campineiro) to 55 (cv. Mazi) mg/100 g. Total ascorbic acid found for cv. Campineiro (85 mg/100 g) was twice the amount found in cv. Dover (40 mg/100 g). Fructose was the predominant soluble sugar in almost all cultivars. The proportion among the main soluble sugars (fructose, sucrose, and glucose) was similar for Oso Grande and Toyonoka cultivars. The flavonol content (quercetin plus kaempferol derivatives) ranged from 2.7 to 7.1 mg/100 g, with a mean value of 6.1 mg/100 g, whereas free ellagic acid ranged from 0.9 to 1.9 and total phenolics varied from 159 to 289 (mean 221) mg/100 g.     

EFFECT OF MATURITY STAGES FOR WINTER- AND SPRING-SOWN CHICKPEA (CICER ARIETINUM L.) ON SEED MINERAL CONTENT

Two-year field experiments were conducted to study the effect of two planting dates and seed maturity on mineral content of chickpea seeds. In 2003 and 2004, chickpea ‘Jubiha-2’ seeds were planted in late December (winter-sown) and early March (spring-sown). For both planting dates, pods were harvested at five maturity stages: 1) beginning of seed fill (BS), 2) full-size seed (FS), 3) greenish-yellow pod (GY), 4) yellow pod (Y), and 5) brown pod (B). The concentrations of nitrogen (N), potassium (K), phosphorus (P), magnesium (Mg), calcium (Ca), and zinc (Zn) on a dry weight basis significantly decreased as the seeds developed from the BS to the FS stage, then did not change significantly at the Y and B stages. Nutrient content (mg seed^?1) increased as the seed dry weight increased. Seeds from spring-sown plants had higher concentrations of N and manganese (Mn) than winter-sown plants. The maximum mineral content of chickpea was achieved at seed physiological maturity.     

Quantification of polyphenolics and their antioxidant capacity in fresh plums

Total phenolics, total flavonoids, and antioxidant capacity of 11 cultivars of fresh plums were determined using spectrophotometric methods. Identification and quantification of individual polyphenolics were performed using reversed-phase high-performance liquid chromatography equipped with a diode array detector. The total phenolic contents of various cultivars widely varied from 125.0 to 372.6 mg/100 g expressed as gallic acid equivalents. The level of total flavonoids in fresh plums ranged between 64.8 and 257.5 mg/100 g expressed as catechin equivalents. Antioxidant capacity, expressed as vitamin C equivalent antioxidant capacity (VCEAC), ranged from 204.9 to 567.0 mg/100 g with an average of 290.9 mg/100 g of fresh weight. Cv. Beltsville Elite B70197 showed the highest amounts of total phenolics and total flavonoids and the highest VCEAC. A positive relationship (correlation coefficient r (2)() = 0.977) was presented between total phenolics and VCEAC, suggesting polyphenolics would play an important role in free radical scavenging. The level of IC(50) value of superoxide radical anion scavenging activity of the plum cultivars ranged from 13.4 to 45.7 mg of VCEAC/100 g. Neochlorogenic acid was the predominant polyphenolic among fresh plums tested. Flavonols found in plum were commonly quercetin derivatives. Rutin was the most predominant flavonol in plums. Various anthocyanins containing cyanidin aglycon and peonidin aglycon were commonly found in all plums except for cv. Mirabellier and NY 101.     

Critical potassium concentration and potassium/ calcium plus magnesium ratio in potato petioles associated with maximum tuber yields

In order to establish critical potassium (K) concentration levels and K/calcium (Ca) plus magnesium (Mg) [K/Ca+Mg] ratios in potato petioles associated to maximum total tuber yields, an experiment was conducted under Brazilian conditions. Six K levels (0, 60, 120, 240, 480, and 960 kg K₂O/ha as potassium sulphate) were applied in a randomized complete block design experiment with four replications. Baraka potato tubers were seeded, spaced 0.8 x 0.3 m, following the agronomic cultural practices recommended for the crop. After 48 days from plant emergence, plant tissue samples was collected from each plant, the youngest fully expanded leaves (YFEL) and the oldest but not senescent leaves (ONSL). Petioles from these leaves were analysed to their K, Ca, and Mg contents. At harvest, total, high grade, and weight tuber yields were increased to 733, 719, and 660 g/plant for the 353, 335, and 384 kg K₂O/ha levels, respectively. These yields are double the Brazilian potato yield average. Petiole Ca and Mg concentrations were decreased by the K fertilizer treatments, whereas the opposite occurred with the K/Ca+Mg ratio. Potassium concentrations in the petioles from the YFEL and ONSL increased up to 10.44 and 7.13 g K/100 g petiole dry matter at the 672 and 654 kg K₂O/ha levels, respectively. The K petiole gradient concentration was not affected by K fertilization. The K/Ca+Mg ratio for YFEL associated with the maximum total tuber yield was 7.24, while the K concentrations were 8.91 and 6.16 g K/100 g dry matter in petioles for the YFEL and ONSL, respectively.     

Correlations of oil and protein with isoflavone concentration in soybean [Glycine max (L.) Merr.

Twelve isoflavones were detected by high-performance liquid chromatography in seeds of 17 soybean [Glycine max (L.) Merrill] cultivars grown at three locations. 6' '-O-Malonyldaidzin and 6' '-O-malonylgenistin together constituted 71-81% of total isoflavones, which ranged in concentration from 2038 to 9514 microg/g and averaged 5644 microg/g across locations and cultivars. The total as well as several individual isoflavones had a moderate negative correlation with oil across locations and cultivars. Six cultivars had a moderate or strong negative correlation of total isoflavones with oil. Five cultivars had a moderate or strong positive correlation of total isoflavones with protein. These results suggest that judicious selection of germplasm for soybean breeding may facilitate development of soybean lines with desirable isoflavone concentrations.     

Effect of seed phosphorus concentration on nodulation and growth of three common bean cultivars

Abstract

An experiment was conducted in the greenhouse to evaluate the effects of seed phosphorus (P) concentration on growth, nodulation, and nitrogen (N) and P accumulation of three common bean (Phaseolus vulgaris L.) cultivars. Seeds were produced under low or high soil P levels, and soaked, or not, in 200 mM KH₂PO₄ solution. The experiment had a 3×3×2×2 factorial block design: three cultivars (ICA Col 10103, Carioca and Honduras 35), three levels of applied P (15, 30 and 45 mg P kg^?1 soil), two native seed P concentrations, and two seed soaking treatments. Plants were harvested at flowering. Soaked seeds increased the number, dry mass and P content of nodules, but did not affect plant growth. Plants originated from seeds with high native P concentration presented higher shoot dry mass and nodule number and mass at every soil P level, and were less responsive to increased soil P supply, than plants from low seed P. In plants from seeds with high P, soil P levels did not alter significantly root dry mass, while in plants from seeds with low P bean cultivars expressed wider differences in root dry mass. The genotypic variability of nodulation was influenced by soil P levels and seed P concentration. Both higher soil or seed P supply enhanced N and P accumulation in shoots. These results indicate that a high seed P concentration produces plants less dependent on soil P supply, and can enhance nodulation and N₂ fixation of common bean. Seed P supply affected the cultivar performance, and should be considered in evaluation of bean genotypes.     

Organic acid contents in onion cultivars (Allium cepa L.)

The following organic acids (glutamic, oxalic, pyruvic, malic, tartaric, citric, and fumaric), pungency, Brix degree, acidity, and pH were determined in onion cultivars (Texas, Guayonje, San Juan de la Rambla, Carrizal Alto, Carrizal Bajo, and Masca) harvested in the same agroclimatic conditions. Glutamic acid was the most abundant organic acid (325 +/- 133 mg/100 g) followed by citric acid (48.5 +/- 24.1 mg/100 g) and malic acid (43.6 +/- 10.4 mg/100 g). There were significant differences between the onion cultivars in the mean concentrations of all of the analyzed parameters. The San Juan de la Rambla and Masca cultivars presented, in general, higher concentrations of the organic acids than the other cultivars. Significant differences in most of the analyzed parameters were observed between the two seed origins for the Masca and San Juan de la Rambla cultivars. The onion samples tended to be classified according to the cultivar and, in the case of San Juan de la Rambla cultivar, according to the precedence of the seeds after applying discriminant analysis.     

Extractable amounts of trans-resveratrol in seed and berry skin in Vitis evaluated at the germplasm level

Extractable amounts of resveratrol in berry skins and seeds were studied in 120 grape (Vitis) germplasm cultivars during two consecutive years to determine the distribution of resveratrol among the main grape genotypes. Interspecific rootstock cultivars had much higher extractable amounts of resveratrol in skin and seed than all other grape genotypes studied in both years. Extremely high extractable amounts of resveratrol in berry skins [>100 microg g(-1) of skin fresh weight (FW)] and seeds (>20 microg g(-1) of seed FW) were observed on two rootstock cultivars obtained from hybrids of V. monticula x V. riparia. Extractable amounts of resveratrol in berries of rootstock cultivars that are the descendants of V. riparia were also very high. The cultivated European type (V. vinifera) cultivars and their hybrids with V. labrusca had relatively low levels of extractable resveratrol in berry skin and seed, and the extractable amounts of resveratrol in berry skin and seeds were, with a few exceptions, <2 microg g(-1) of skin or seed FW. Extractable amounts of resveratrol in berry skin and seeds were closely related with fruit traits or purpose of uses and climate. Significantly higher extractable amounts of resveratrol in berry skin were found in seeded cultivars than in seedless ones, in both berry skin and seeds in winemaking grapes than in table grapes, and in red grapes than in green ones. Moreover, rainfall during fruit development resulted in higher extractable amounts of resveratrol in berry skin, whereas resveratrol synthesis and accumulation in grape seeds were not related to climate change.