Impact of boron, calcium and genetic factors on vitamin C, carotenoids, phenolic acids, anthocyanins and antioxidant capacity of carrots (Daucus carota)

Carrots (Daucus carota L.) were used to investigate the effects and interactions of cultivar and mineral supply on the nutritional quality (antioxidant potential, vitamin C, carotenoids and phenolic acids) of the resulting storage roots. The supplement of boron (B) and or calcium (Ca) in the feeding solutions, during plant growth, influenced the accumulation of other minerals, such as P, K, Mg, S and Na, in the storage roots (p < 0.05). When no additional B or Ca was supplied (e.g. −B or −Ca treatment), we observed 33-50% increase in the accumulated levels of α- and β-carotenes, and 45-70% increase of vitamin C. Carrots grown with no supplement of B in the nutrient solutions (e.g. −B treatment and −ve control) had significantly higher (p < 0.001) levels of total phenolic acids compared to the carrots with the supplement of B (e.g. −Ca treatment and +ve control). A strong positive correlation was observed between the total phenolic contents and ORAC values (r = 0.932) in all the cultivars. The results suggest that both cultivar and mineral supply were major determinants of nutritional quality of the carrots. The nutritional value of carrot crops (with an acceptable physical quality) can be enhanced by manipulating mineral nutrient applications.     

Effect of thermal and high pressure processes on structural and health-related properties of carrots (Daucus carota)

In the present study, the effect of thermal and equivalent high pressure processes on structural (texture and microstructure) and health-related (total β-carotene concentration, β-carotene isomerisation and β-carotene bio-accessibility) properties of carrots was investigated. Both a mild and strong pasteurisation process and a sterilisation process were considered.     

Chemical and antioxidative assessment of dietary turnip (Brassica rapa var. rapa L.)

The phenolic compounds and organic acids of turnip (Brassica rapa var. rapa L.) edible parts (leaves and stems, flower buds and roots) were determined by HPLC–DAD and HPLC–UV, respectively. The results revealed a profile composed of 14 phenolics (3-p-coumaroylquinic, caffeic, ferulic and sinapic acids, kaempferol 3-O-sophoroside-7-O-glucoside, kaempferol 3-O-sophoroside-7-O-sophoroside, kaempferol 3-O-(feruloyl/caffeoyl)-sophoroside-7-O-glucoside, kaempferol 3,7-O-diglucoside, isorhamnetin 3,7-O-diglucoside, kaempferol 3-O-sophoroside, 1,2-disinapoylgentiobiose, 1,2′-disinapoyl-2-feruloylgentiobiose, kaempferol 3-O-glucoside and isorhamnetin 3-O-glucoside) and six organic acids (aconitic, citric, ketoglutaric, malic, shikimic and fumaric acids). The quantification of the identified compounds showed kaempferol 3-O-sophoroside-7-O-glucoside, kaempferol 3-O-(feruloyl/caffeoyl)-sophoroside-7-O-glucoside, isorhamnetin 3,7-O-diglucoside and isorhamnetin 3-O-glucoside as the main phenolics, and malic acid as the organic acid present in highest amounts. A screening of the antioxidative potential was also performed by means of the DPPH radical scavenging assay. Turnip flower buds exhibited the strongest antioxidant capacity.     

Composition of the essential oil of Daucus gingidium L. ssp. gingidium

The essential oils obtained from leaves and fruits of Daucus gingidium ssp. gingidium have been studied. The main constituents of the essential oil from the leaves were sabinene (26.8%), α-pinene (10.8%), germacrene D (6.9%) and limonene (5.7%). Sabinene (60.6%) was the main compound identified in the essential oil of the fruits, followed by α-pinene (12.2%) and 4-terpineol (5.4%). Furthermore, qualitative and quantitative considerations about differences with literature data on Daucus carota have been made in order to confirm the species status of D. gingidium.     

Immunomodulatory and anticancer activities of phenolics from emblica fruit (Phyllanthus emblica L.)

There is a paucity of studies on the immunomodulatory properties of fruit extracts of emblica with the emphasis on lymphocytes. Therefore, the aim of the study was to evaluate the immunomodulatory properties and anticancer potential of six phenolic compounds from emblica fruit by in vitro proliferation assay. Effects of these compounds on splenocyte proliferation and the cytotoxicity to both human breast cancer cell (MCF-7) and human embryonic lung fibroblast cell (HELF) were determined by the MTT method. Significantly stimulatory effects (P < 0.05) were found for geraniin and isocorilagin. The concentration of geraniin, quercetin 3-β-d-glucopyranoside, kaempferol 3-β-d-glucopyranoside, isocorilagin, quercetin, kaempferol and rutin to obtain 50% of stimulatory effect was 56, 123, 242, 42, 73, 93 and 92 μg/ml, respectively. The assay of anticancer activities suggested that geraniin and isocorilagin exhibited higher cytotoxicities than other compounds against MCF-7 with IC₅₀ of 13.2 and 80.9 μg/ml, respectively. Isocorilagin exhibited a strong cytotoxicity to HELF cell with IC₅₀ of 51.4 μg/ml. Geraniin, quercetin, kaempferol and their glycosides had weak cytotoxicity against HELF cells. Paclitaxel showed a strong cytotoxicity to MCF-7 and HELF with IC₅₀ of 6.8 and 14.5 μg/ml, respectively. These findings are in line with the reported potent antioxidant activity. These results suggested that the antitumour activity of these compounds might be achieved by immunomodulatory properties which could partially be attributed to their antioxidant activity.     

Identification of phenolics in the fruit of emblica (Phyllanthus emblica L.) and their antioxidant activities

An activity-directed fractionation and purification process was used to identify the antioxidative components of emblica fruit. Dried fruit of emblica was extracted with methanol and then partitioned by ethyl ether, ethyl acetate, butanol and water. The ethyl acetate fraction showed the strongest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity among four fractions. The ethyl acetate fraction was then subjected to separation and purification using Sephadex LH-20 chromatography and reverse-phase high-performance liquid chromatography (HPLC). Six compounds were identified to be geraniin (1), quercetin 3-β-d-glucopyranoside (2), kaempferol 3-β-d-glucopyranoside (3), isocorilagin (4), quercetin (5), and kaempferol (6), respectively, by spectral methods, ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy, ultraviolet–visible (UV–Vis) spectrophotometry and mass spectroscopy (MS), and comparison with literatures. Compounds 2–4 and 6 were identified from emblica fruit for the first time. Furthermore, the antioxidant activities of purified compounds were screened for their antioxidative potential using lipid peroxidation and DPPH systems. All the purified compounds showed strong antioxidant and radical scavenging activities. Amongst, geraniin showed the highest antioxidant activity (4.7 and 65.7 μM of IC₅₀ values for DPPH and lipid peroxidation assay, respectively) than other purified compounds.     

Free radical scavenging activities and bioactive substances of Jerusalem artichoke (Helianthus tuberosus L.) leaves

The total phenolic content and radical scavenging activities of Jerusalem artichoke (Helianthus tuberosus L.) leaves were investigated. Results indicated that the ethyl acetate fraction contained the highest total phenolic content (266.69 ± 2.51 mg GAE/g dry extract) accompanied with strongest free radical scavenging abilities. Following an in vitro radical scavenging activity-guide fractionation procedure, six phenolic compounds which strongly quenched free radicals were separated from ethyl acetate fraction. Among them, 3-O-caffeoylquinic acid and 1,5-dicaffeoylquinic acid played a dominant role due to their strong free radical scavenging abilities and their high contents. The content of 3-O-caffeoylquinic acid in n-butanol fraction was 74.58 ± 1.05 mg/g, while 1,5-dicaffeoylquinic acid in ethyl acetate fraction was 104.51 ± 2.86 mg/g. The results imply that the leaves of Jerusalem artichoke might be a potential source of natural antioxidants.     

Isolation and chemical evaluation of carob (Ceratonia siliqua L.) seed germ

The present investigation was undertaken in order to study the influence of the dehusking procedure on the germ meal composition of carob (Ceratonia siliqua L.) seeds and also to investigate its detailed composition and nutritive value. Meals of carob seed germ were obtained by acid treatment or boiling water treatment of the whole seeds. These procedures allowed to separation of the tight-fitting brown coat of the seed and the removal of the endosperm. Results indicated that the carob germ meal composition could be affected by the isolation procedures. Small reductions were observed in protein and lipid contents in germ meals from acid extraction. The analysis of the carob germ meal (containing fine fragments of husk and endosperm), which could be really obtained industrially, showed the following composition: moisture 8.3%, ash 6.5%, lipids (neutral and polar) 6.6% containing ∼21% of polar lipids, crude proteins 54.7% and energy value 17.5 kJ/g.     

Genetic and environmental effects on chemical composition related to sensory traits in common beans (Phaseolus vulgaris L.)

The chemical composition determines plant-derived foods’ sensory traits; genetic and environmental effects and their interactions determine chemical composition. Understanding the importance of each factor should help characterise foodstuffs according to the variety and place of cultivation. We studied the effects of variety (five landraces + two checks) and environment (five locations and two years) on some molecules important for beans’ (Phaseolus vulgaris L.) sensory value. The greatest location effects were on protein and starch content and variety effects were due to combinations of traits (mainly sucrose, protein, and malic acid). The variety × location interactions detected in protein, sucrose, citric acid, and malic acid were difficult to associate to the gastronomic success of a particular variety cultivated at a particular location. Our results showed that protected designation of origin (PDO) in beans could be delimited on the basis of chemical composition, derived from the particular environmental characteristics of a region and the genetic characteristics of the varieties admitted.     

Fat and fatty acids of white lupin (Lupinus albus L.) in comparison to sesame (Sesamum indicum L.)

The study was undertaken to compare fat and fatty acid profiles in white lupin (Lupinus albus ssp. albus) and sesame (Sesamum indicum L.), representing two different families, Fabaceae and Pedaliaceae. Fat levels were 10.74% and 55.44% in seeds of white lupin and sesame, respectively. The results indicated that oleic, linolenic and arachidic acids in seed fat were higher in white lupin than in sesame cultivars. Oleic acid was the predominant fatty acid in white lupin, whereas linoleic acid was predominant in sesame. Fat content (%) was statistically significantly correlated with linoleic, linolenic and arachidic acids at the genotypic level. The fatty acid composition of white lupin is useful for human consumption. Although oil content of white lupin was lower than that of sesame, white sweet lupin could be improved.     

Effects of alkali neutralization with CO2 on fermentation, chemical parameters and sensory characteristics in Spanish-style green olives (Olea europaea L.)

This paper aimed to study CO₂ use as alkali neutralizing agent instead of the traditional washings with water, in Spanish-style green olives. Titratable acidity, pH, sugars and microbial populations were monitored during processing. CO₂ treatment was effective in reducing water-soluble carbohydrate loss from the olives during washing step and affected combined acidity and lactic acid fermentation. The final pH of the fermented brine was higher than in control, mainly due to high buffering capacity of the solution. CO₂ treatment allowed the reduction of more than 80% of the wastewaters. Sensory evaluations of the end product were carried out. Olives treated with CO₂ were perceived to be more intense in acidic taste than control, while for texture attributes no differences were detected.     

Comparative study of primary and secondary metabolites in 11 cultivars of persimmon fruit (Diospyros kaki L.)

Primary metabolites (sugars, organic acids) and secondary metabolites (phenolics and carotenoids) were quantified by HPLC in fully ripe fruit of 11 kaki cultivars: ‘Amankaki’, ‘Cal Fuyu’, ‘Fuji’, ‘Hana Fuyu’, ‘Jiro’, ‘O’Gosho’, ‘Tenjin O’Gosho’, ‘Thiene’, ‘Tipo’, ‘Tone Wase’ and ‘Triumph’. Amongst the analysed cultivars, ‘Tone Wase’ stands out as the richest in sugars, particularly glucose, and cultivars ‘Tipo’ and ‘Triumph’ contained the highest amounts of organic acids. Cultivars ‘O’Gosho’, ‘Cal Fuyu’ and ‘Hana Fuyu’ contained the least sugars and cultivar ‘Jiro’ the least organic acids. Amongst the individual phenolic compounds catechin and gallic acid were present in highest concentrations. The predominant carotenoid in both skin and pulp of ripe persimmon fruit was β-carotene, the highest content was measured in skin of cultivar ‘Hana Fuyu’, which also contained the highest level of total carotenoids. In persimmon pulp, much lower values for carotenoids were obtained, particularly in fruit of cultivar ‘Cal Fuyu’.     

European elderberry (Sambucus nigra L.) rich in sugars,organic acids,anthocyanins and selected polyphenols

Sugars and organic acids in the fruit of two cultivars and three selections of black elderberry (Sambucus nigra L.): ‘Haschberg’, ‘Rubini’, ‘Selection 13’, ‘Selection 14’ and ‘Selection 25’ were quantified. The anthocyanin as well as quercetin profiles of this plant material were also established by the use of HPLC/MS. Significant differences in the concentration of sugars and organic acids were detected between the widely spread cultivar ‘Haschberg’ and all other cultivars/selections; ‘Haschberg’ was the richest in organic acids (6.38 g kg⁻¹ FW), and it contained the least sugar (68.5 g kg⁻¹ FW). The following major cyanidin based anthocyanins were identified in the fruit of black elderberry: cyanidin 3-sambubioside-5-glucoside, cyanidin 3,5-diglucoside, cyanidin 3-sambubioside, cyanidin 3-glucoside and cyanidin 3-rutinoside. The most abundant anthocyanin in elderberry fruit was cyanidin 3-sambubioside, which accounted for more than half of all anthocyanins identified in the berries. The ‘Rubini’ cultivar had the highest amount of the anthocyanins identified (1265 mg/100 g FW) and the lowest amount was measured in berries of the ‘Selection 14’ (603 mg/100 g FW). The ‘Haschberg’ cultivar contained a relatively low amount of anthocyanins in ripe berries (737 mg/100 g FW). From the quercetin group, quercetin, quercetin 3-rutinoside and quercetin 3-glucoside were identified; the latter prevailing in black elderberry fruit. The cultivar with the highest amount of total quercetins was ‘Selection 25’ (73.4 mg/100 g FW), while the ‘Haschberg’ cultivar contained average amounts of quercetins (61.3 mg/100 g FW). The chemical composition of the ‘Haschberg’ cultivar, the most commonly planted, conforms to the standards for sugars, anthocyanins and quercetins and exceeds them in the content levels of organic acids, the most important parameter in fruit processing.     

Antioxidant flavonol glycosides in mulberry (Morus alba L.) leaves isolated based on LDL antioxidant activity

Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Antioxidants that prevent LDL from oxidation may reduce atherosclerosis. We investigated LDL antioxidant activity and extracted compounds of mulberry (Morus alba L.) leaves. The LDL antioxidant activity of 60% ethanol extracted of mulberry leaves, which inhibits human LDL oxidation induced by copper ion, was determined on the basis of oxidation lag time and calculated as epigallocatechin 3-gallate equivalents (58.3 μmol of EGCG equivalent/g of dry weight). Three flavonol glycosides [quercetin 3-(6-malonylglucoside), rutin (quercetin 3-rutinoside) and isoquercitrin (quercetin 3-glucoside)] were identified as the major LDL antioxidant compounds by LC-MS and NMR. The amounts of these flavonol glycosides in mulberry leaves and mulberry-leaf tea were determined by HPLC. Our results showed that quercetin 3-(6-malonylglucoside) and rutin were the predominant flavonol glycosides in the mulberry leaves.     

Extraction and characterisation of pectin methylesterase from black carrot (Daucus carota L.)

This study was carried out to determine some of the biochemical properties of pectin methylesterase (PME) from black carrot. The enzyme showed very high activity in a broad pH range of 6.5–8.5, with the optimum pH occurring at 7.5. The optimum temperature for maximal PME activity was found to be 55 °C. NaCl enhanced PME activity, particularly at 0.2 M. K_m and V_max values for black carrot PME using apple pectin as substrate were found to be 2.14 mg/ml (r² = 0.988) and 3.75 units/ml, respectively. The enzyme was stable between the temperatures of 30–50 °C/5 min whereas it lost nearly all of its activity at 70 °C/5 min. E_a and Z values were found to be 196.8 kJmol⁻¹ (r² = 0.996) and 2.16 °C (r² = 0.995), respectively.     

Antioxidant activity in different parts of roselle (Hibiscus sabdariffa L.) extracts and potential exploitation of the seeds

The calyx of the roselle plant has long been recognised as a source of antioxidants. The objective of this study was to evaluate antioxidant activity, free radical-scavenging and total phenolic content in other parts of the roselle plant. Roselle seed extracts were found to have the highest antioxidant activity and strongest radical-scavenging activity of all plants tested. Methanol extracts showed a positive correlation between phenolic content and antioxidant activity, as measured by β-carotene bleaching assay and DPPH radical-scavenging activity. The antioxidant efficacy of roselle seeds in a whole food system was investigated by testing the effect on lipid oxidation in cooked beef patties stored at 4 °C for 14 days. Results showed that patties treated with roselle seeds had reduced lipid oxidation compared to patties treated with BHT. This study suggests that roselle seeds have the potential to be used as food antioxidants.     

Potassium rate alters the antioxidant capacity and phenolic concentration of basil (Ocimum basilicum L.) leaves

In the current study, we have determined how potassium rate affects the phenolic levels and antioxidant properties of three cultivars of basil (Ocimum basilicum L.) leaves: Dark Opal, Sweet Thai, and Genovese. Potassium rate increased the total phenolic concentration in basil, with basil treated at the highest potassium rate, 5.0 mM K, containing greater phenolic levels than basil treated at the lowest potassium rate, 1.0 mM K (p = 0.008). Basil grown at 5.0 mM K also had higher concentrations of rosmarinic (p = 0.005) and chicoric (p < 0.001) acids compared to lower potassium treatment levels. Correspondingly, 1.0 mM K basil had lower DPPH (2,2′-diphenyl-1-picrylhydrazyl) (p ? 0.005) and FRAP (ferric reducing antioxidant power, p = 0.043) antioxidant capacities compared to basil treated at higher potassium rates. Cultivar was also found to impact the phenolic composition and antioxidant properties of basil, with Sweet Thai having lower total phenolic concentrations and FRAP antioxidant capacities than Dark Opal and Genovese. Although not affected by potassium rate, anthocyanin concentrations varied significantly among the cultivars, with purple Dark Opal basil exhibiting higher anthocyanin levels than Sweet Thai (p = 0.003) and Genovese (p = 0.002).     

Volatile compounds from pitanga fruit (Eugenia uniflora L.)

Extracts from pitanga leaves are considered to be effective against many diseases, and are therefore used in popular Brazilian medicines. In this study, the volatile constituents of pitanga fruits (Eugenia uniflora L.) were trapped on to Porapak-Q and eluted with ethyl acetate, and the chemical composition of the extract was analyzed by gas chromatography and gas chromatography/mass spectrometry. Fifty-four compounds were detected, and twenty-nine of those were identified by close matches with standard MS spectra. Monoterpenes (75.3% in mass) were found to comprise the largest class of the pitanga fruit volatiles, including trans-β-ocimene (36.2%), cis-ocimene (13.4%), the isomeric β-ocimene (15.4%) and β-pinene (10.3%). Several known therapeutic constituents of pitanga leaf extract, such as selina-1,3,7(11)-trien-8-one (the major constituent) were also found to be present in the fruit volatile extract, suggesting that the fruit may display therapeutic properties similar to those of the leaf extract.     

Variations in phenolic composition and antioxidant properties among 15 basil (Ocimum basilicum L.) cultivars

In this study, the influences of cultivar on the phenolic composition and antioxidant properties of 15 different basil varieties was determined. Cultivar had a statistically significant effect on total phenolic levels (p < 0.001) and anthocyanin concentrations (p < 0.001). Analysis of individual phenolic acid levels by high-performance liquid chromatography showed substantial variations in the phenolic acid profiles among cultivars. Rosmarinic (p < 0.001), chicoric (p = 0.002) and caffeic (p = 0.001) acid concentrations were affected by cultivar, although caftaric acid levels (p = 0.083) were not. Nine of the cultivars in this study contained chicoric acid in higher concentrations than rosmarinic acid. These are the first basil cultivars that have been identified in which rosmarinic acid is not the dominant phenolic acid. In addition, six of the cultivars in this study had caftaric and caffeic acid concentrations that were similar or higher than rosmarinic acid levels. Cultivar also had a significant impact on both FRAP (ferric reducing antioxidant power, p = 0.007) and DPPH (2,2′-diphenyl-1-picrylhydrazyl, p = 0.004) antioxidant capacities. For the basil cultivars in this study, the individual phenolic acid composition was found to be an important factor influencing the measured antioxidant capacity.