Improving the phytochemical composition of broccoli sprouts by elicitation

In order to increase the concentrations of bioactive compounds in broccoli sprouts, exogenous elicitors: methionine, tryptophan, chitosan, salicylic acid (SA) and methyl jasmonate (MeJA) were sprayed at different concentrations during germination. The effects of the elicitors on vitamin C, phenolic compounds and glucosinolate levels were assessed in 3, 5 and 7-days old seedlings. The application of 200, 300 μM SA and 0.01% chitosan induced increases, by 26%, 18% and 54%, respectively in the content of vitamin C in 5 days old broccoli sprouts. Flavonoid concentration was also increased by 31% and 33% after 10 μM MeJA and 100 μM SA treatments, respectively in 7 days old broccoli sprouts. In contrast, methionine or tryptophan solutions did not positively affect the vitamin C or the phenolic compounds in the sprouts. The individual classes of glucosinolates respond differently to the elicitor treatment. Methionine, a sulphur-containing amino acid, applied at 5 mM, significantly increased, by 32%, the levels of aliphatic glucosinolates. However, indole glucosinolates presented a significant response to the induction with tryptophan, SA or MeJA treatments. Tryptophan at 10 mM concentration augmented by 1.8-fold the indole glucosinolate concentration in 7 days old broccoli sprouts, and the treatments of 100 μM SA and 25 μM MeJA also induced significantly higher amounts of indole glucosinolates (by 33% and 51%, respectively) in 7 days old treated broccoli sprouts. Therefore, the application of elicitors could be a useful tool for improving the bioactive metabolites in broccoli sprouts for fresh consumption or functional ingredients for nutraceuticals foods.     

Flavonoids, sugars and fruit acids of alpine bearberry (Arctostaphylos alpina) from Finnish Lapland

Alpine bearberry (Arctostaphylos alpina L.) is a special circumpolar edible berry primarily used for household purposes but with greater potential in commercial applications than utilized thus far. In this study, the flavonoids of alpine bearberry were investigated with HPLC-DAD and HPLC-MS, and the sugars and fruit acids as trimethylsilyl derivates with GC-FID. The most abundant anthocyanin was cyanidin-3-O-galactoside accounting for over 95% of the anthocyanins. Eight other anthocyanins existed in trace amounts only, the richest of them being cyanidin-3-O-arabinoside and cyanidin-3-O-glucoside. Cyanidin accounted for over 99% of the anthocyanin aglycones. All the flavonols identified were glycosides of quercetin. Majority of the sugars were glucose and fructose while the most abundant fruit acid was quinic acid. The unique anthocyanin composition of alpine bearberry encourages advanced use of the berry as a food ingredient in private households and in industrial applications. In addition, it serves as a unique reference material for research purposes.     

Effect of 2, 4-epibrassinolide on main health-promoting compounds in broccoli sprouts

The combined treatment with 2, 4-epibrassinolide (EBR) (2, 20, and 200 nmol/L) and NaCl (0, 40, and 160 mmol/L) on the germination rate, fresh weight, contents of ascorbic acid and glucosinolates, activities of myrosinase and antioxidant ability of broccoli sprouts was investigated. The influence of EBR on the content of glucosinolates in broccoli sprouts varied with the concentrations of EBR and NaCl. The content of total glucosinolates and glucoraphanin in broccoli sprouts treated with 2 nmol/L EBR plus 40 mmol/L NaCl was increased by 86% and 85%, respectively, and the activity of myrosinase was significantly improved by 20 nmol/L EBR treatment with or without NaCl. In addition, the content of ascorbic acid was significantly increased after treatment with 20 nmol/L EBR, and the combined treatment with 20 nmol/L EBR plus 40 mmol/L NaCl significantly enhanced the accumulation of ascorbic acid when compared with the 40 mmol/L NaCl treatment alone. These results indicated that the combined treatment with 2 nmol/L EBR plus 40 mmol/L NaCl as well as EBR treatment solely at 20 nmol/L could be useful ways for selective increase of glucosinolates or ascorbic acid, the main health-promoting compounds in broccoli sprouts.     

Genotypic effects on the phytochemical quality of seeds and sprouts from commercial broccoli cultivars

Determining ontogenic diversity in vegetables, in general or Brassicas in particular, regarding the bioactive content, is an interesting task since the most promising Brassicaceae foods could have the highest nutritional and health-promoting properties. Therefore, vitamin C, phenolic compounds, glucosinolate content, and total antioxidant capacity were evaluated in commercial cultivars of broccoli (Brassica oleracea var. italica; cv. Nubia, cv. Marathon and cv. Viola) seeds and during the sprouting period. Vitamin C was not detected in dormant seeds and its content increased with the germination, reaching values ranging from 53 (cv. Nubia) to 64 (cv. Marathon) mg/100 g FW, at the end of the monitored period (14days). The total glucosinolate content in seeds and 3-day-old sprouts was higher in cv. Marathon (1005 and 556 mg/100 g FW, respectively), however cv. Viola sprouts registered the highest glucosinolate content 7 and 14 days after sowing (235 and 208 mg/100 g FW, respectively). Aliphatic glucosinolates were more affected by genetic factors than the indolic glucosinolates, being glucoraphanin the predominant glucosinolate in cv. Nubia and cv. Marathon, whereas glucoiberin was the major glucosinolate in cv. Viola. The flavonoid and total phenolic content was significantly higher in cv. Viola. Also, seeds of this cultivar showed the highest antioxidant capacity (2.7 mg Trolox/g FW).     

STABILITY OF ANTHOCYANINS, PHENOLS AND FREE RADICAL SCAVENGING ACTIVITY THROUGH SUGAR ADDITION DURING FROZEN STORAGE OF BLACKBERRIES

Influence of sugar and mixtures of sugar on color retention of two varieties of blackberries, Thornfree and Cacanska bestrna, were investigated during storage at − 18C for 12 months. After harvest, blackberries were coated with sugars (sucrose, fructose and glucose) and different sugar (sucrose  +  fructose  +  glucose, fructose  +  glucose, fructose  +  sucrose) mixtures. Anthocynin content, total phenol content and free radical scavenging activity of prepared samples were evaluated. Ratio of fruit : sugar was 1:1. The highest anthocyanin retention was in blackberry samples with glucose addition and the lowest in samples with sucrose addition, in both cultivars. Blackberry samples with sucrose addition had even lower retention than samples without sugar addition. Samples with an addition of other sugars had higher retention of anthocyanin than samples stored without sugars.

PRACTICAL APPLICATION

Possibility of phenols retention of blackberries due to sugar addition, during cold storage was investigated. Results showed that glucose had the most positive effect on anthocyanins retention as well as total phenolic compounds content. For that reason, certain amount of sucrose in fruit preserves can be replaced by addition of glucose, and for that reason retention of phenolic compounds can be higher and, as could be expected, more effective against oxidative stress in human body due to intake of product formulation with glucose.     

白光和红光光周期对西兰花芽苗菜生理生化和萝卜硫苷代谢的影响

本文研究了白光和红光不同光周期（0、4、8、12、16和20 h·d?1）对西兰花芽苗菜生长、可溶性糖、可溶性蛋白、抗坏血酸、花色苷和萝卜硫苷代谢的影响。结果表明:光照抑制西兰花芽苗的生长,红光较白光处理能够促进西兰花芽苗芽长增长;随着光周期的延长,西兰花芽苗菜中可溶性糖、可溶性蛋白、抗坏血酸、萝卜硫苷和总硫苷含量、黑芥子酶活力以及萝卜硫素含量均呈现先增加后降低的趋势。相较于白光,红光明显提高了西兰花芽苗菜中可溶性糖、可溶性蛋白、抗坏血酸和萝卜硫苷含量。但白光处理下花色苷含量明显高于红光处理。在光周期小于12 h·d?1时,红光处理下萝卜硫素形成量显著高于白光处理（P<0.05）,而当光周期大于12 h·d?1时,红光处理下萝卜硫素形成与白光处理之间差异不显著甚至低于白光处理。总之,红光相较于白光更有利于提高西兰花芽苗菜的产量和营养品质,12 h·d?1是比较适合的光周期。     

Effect of nitrogen and sulfur fertilization on glucosinolates in the leaves and roots of broccoli sprouts (Brassica oleracea var. italica)

Broccoli (Brassica oleracea L. var. italica cv. Marathon) sprouts are a rich source of glucosinolates, particularly 4‐methylsulfinylbutyl glucosinolate (glucoraphanin), the precursor of the chemoprotective isothiocyanate, sulforaphane. Sulfur and nitrogen fertilization have been shown to influence the pattern and levels of glucosinolates in mature broccoli, but little information is available on the fertilization of sprouts, a transient stage of broccoli growth, which have been recommended for salads. Therefore, an experiment was set up to evaluate the effect of N and S fertilization on the glucosinolate content of the aerial part and roots of broccoli sprouts. Nitrogen was tested at 0, 45.5, 91.0 mg L^?1 and sulfur at 0, 14.6 and 29.2 mg L^?1. The results showed that total glucosinolates in the aerial part were significantly higher (P < 0.001) than in the roots. The major glucosinolates in the aerial part were 4‐methylsulfinylbutyl and 3‐methylsulfinylpropyl whereas in the roots they were 2‐phenylethyl and 4‐methylthiobutyl. Fertilization of broccoli sprouts had a significant (P < 0.001) detrimental effect on the levels of aliphatic glucosinolates whereas the opposite was noted for indole and aromatic glucosinolates, for some of the fertilization combinations tested. Overall, the results indicate that broccoli sprouts do not benefit from fertilization. Copyright © 2006 Society of Chemical Industry     

Production of Anthocyanin from Strawberry Cell Suspension Cultures; Effects of Sugar and Nitrogen

Production of anthocyanins was investigated, controlling sugar concentration and ratio of ammonium: nitrate in culture medium of strawberry, Fragaria ananassa cv Shikinari. Anthocyanins were produced under 8000 lux for 2 wk using calli derived from suspension cultures of leaf tissues. Yield was greatest in modified LS medium containing 5% sucrose (W/V), a ratio of NH⁺₃ (2 mM):NO^?₃ (28mM), 2,4-dichlorophenoxyacetic acid and benzyladenine. Total anthocyanin was about 15 mg/100 mL of culture medium, almost six times greater than that in MS medium. Effects of sugars were also studied using eight sugars. Cell growth and anthocyanin accumulation were enhanced by glucose, sucrose, and fructose, but anthocyanin compositions were not affected. Major anthocyanins were peonindin-3-glucoside and cyanidin-3-glucoside. Peonidin-3-glucoside increased with an increase in the NH⁺₄ NO^?₃ ratio at nitrogen concentration 30 mM, while that of cyanidin-3-glucoside changed vice versa.     

Stability of anthocyanins and sugars during heating for low sugar meoru (Vitis coignetiea) jam-making under singlet oxygen

Stability of meoru (Vitis coignetiea) anthocyanins during heating under singlet oxygen to simulate low sugar meoru jam-making was studied. Samples consisted of meoru juice, sugars (sucrose, glucose, or fructose), and pectin were placed at 10 or 90°C under singlet oxygen which was produced with riboflavin under 5,500 lx. Anthocyanins present in samples were malvidin-3,5-diglucoside, delphinidin-3-glucoside, cyanidin-3,5-diglucoside, malvidin-3-glucoside, and cyanidin-3-glucoside in a decreasing order. Meoru anthocyanins were degraded under singlet oxygen and heating accelerated the degradation. Degradation was faster in monoglucoside anthocyanins than diglucoside anthocyanins, and in samples added with sucrose or fructose than in samples with glucose. Sucrose in samples was hydrolyzed to glucose and fructose possibly by acid present in meoru, at higher rate at 90°C than at 10°C. Simple sugars added or produced by hydrolysis of sucrose were stable during heating or at 10°C under singlet oxygen, possibly due to quenching activity of meoru anthocyanins on singlet oxygen.     

Radish sprouts—Characterization and elicitation of novel varieties rich in anthocyanins

The anthocyanin profile of two varieties of red radish sprouts (Raphanus sativus), cv. China rose and Rambo, were studied using HPLC-DAD-ESI-MSⁿ and HPLC-DAD. The most abundant type of anthocyanin was cyanidin and its derivatives, with one or two acylating groups, with qualitative and quantitative differences among varieties. Some compounds were identified for the first time in both varieties, to the best of our knowledge. Radish sprouts were treated during germination (days 3 to 8) using methyl jasmonate, jasmonic acid, salicylic acid, sucrose and glucose as elicitors in order to enrich their total anthocyanin content (TAC). An increase in TAC was achieved by 50% in China rose radish sprouts and by 30% in Rambo red radish after glucose treatment. Methyl jasmonate and sucrose also contribute to enhance TAC. Enriching natural food in anthocyanins may contribute to sustaining their regular intake with preventive and therapeutic roles in a number of human diseases.     

Glucosinolates in broccoli sprouts (Brassica oleracea var. italica) as conditioned by sulphate supply during germination

Sulphur (S) fertilization is essential for primary and secondary metabolism in cruciferous foods. Deficient, suboptimal, or excessive S affects the growth and biosynthesis of secondary metabolites in adult plants. Nevertheless, there is little information regarding the influence of S fertilization on sprouts and seedlings. An experiment was set up to evaluate the effect of S fertilization, supplied as K(2)SO(4) at 0, 15, 30, and 60 mg/L, on the glucosinolate content of broccoli sprouts during the germination course of 3, 6, 9, and 12 d after sowing. Glucosinolate concentration was strongly influenced by germination, causing a rapid increase during the first 3 d after sowing, and decreasing afterwards. The S supply increased aliphatic and total glucosinolate content at the end of the monitored sprouting period. S-treated sprouts, with S(15), S(30), and S(60) at 9 and 12 d after sowing presented enhanced glucosinolate content. Overall, both germination time and S fertilization were key factors in maximizing the bioactive health-promoting phytochemicals of broccoli. Practical Application: Germination with sulphate is a simple and inexpensive way to obtain sprouts that contain much higher levels of glucosinolates (health promoting compounds), than the corresponding florets from the same seeds.     

Intensifying sulforaphane formation in broccoli sprouts by using other cruciferous sprouts additions

Sulforaphane is a significant chemopreventive compound which is the predominant glucosinolate in broccoli sprouts. However, the existence of the epithiospecifier protein could direct the hydrolysis of glucosinolates toward sulforaphane nitrile formation instead of sulforaphane. Therefore, the study aimed on improving the yielding of sulforaphane in broccoli sprouts with a new method of the united hydrolysis of cruciferous sprouts. According to the results, the addition of radish, rocket and rape sprouts to broccoli sprouts could promote the hydrolysis of the glucoraphanin to anticancer effective sulforaphane to 2.03, 2.32 and 1.95-fold, respectively, compared to single broccoli sprouts. Meanwhile, the formation of non-bioactive sulforaphane nitrile in these three groups decreased greatly. However, the addition of mustard sprouts had no positive effect. These observations could make a contribution to the potential chemoprotective effects of broccoli sprouts.     

Influence of the chemical structure on the thermal degradation of the glucosinolates in broccoli sprouts

Glucosinolates are secondary plant metabolites occurring in Brassica vegetables. Food processing significantly reduces glucosinolate content, among other things due to thermal degradation. As there is only little information about thermal glucosinolate breakdown, the influence of the chemical structure as well as the influence of different pH to thermal degradation of individual glucosinolates was studied by analysing desulphoglucosinolates with HPLC-DAD. Thermal degradation was forced by heating broccoli sprouts at 130 °C in dry medium, whereas the influence of the pH was studied by cooking at 100 °C in aqueous medium. Within each group of glucosinolates differences in thermal degradation were revealed. Within the sulphur containing aliphatic glucosinolates the oxidative state of the sulphur atom as well as the side chain length influenced the reactivity. Among the indole glucosinolates great differences in stability were observed. A hydroxyl function in the side chain generally seems to destabilise glucosinolates. Glucosinolates were most stable towards thermal treatment in neutral and slightly acidic medium, whereas they degraded more rapidly in basic medium.     

外源蔗糖对萝卜幼苗品质及代谢酶活性的影响

以“满堂红”品种的萝卜为材料,探究不同质量浓度的外源蔗糖喷洒处理对不同生长天数的萝卜幼苗营养品质（花青素、叶绿素、类胡萝卜素、总酚和芥子油苷等含量）及代谢酶（过氧化物酶（peroxidase,POD）和苯丙氨酸解氨酶（phenylalanine ammonialyase,PAL））活性的影响。结果表明：对于生长3、5 d和7 d的萝卜幼苗,0.4 g/100 mL和0.6 g/100 mL蔗糖处理均能够显著提高其花青素、叶绿素、类胡萝卜素、总酚、芥子油苷含量及POD、PAL活性（P＜0.05）,而0.2 g/100 mL蔗糖处理对其营养物质含量及抗氧化性的影响不显著（P＞0.05）;0.4 g/100 mL和0.6 g/100 mL蔗糖处理在改善其营养价值方面的差别不大。因此,在农业生产中,可采用质量浓度0.4 g/100 mL蔗糖喷洒处理萝卜幼苗来提高其营养价值。     

Glucosinolate content of brassica vegetables: Analysis of twenty-four cultivars of calabrese (green sprouting broccoli,Brassica oleracea L. var. botrytis subvar. cymosa Lam.)

The contents of glucosinolates in twenty-four cultivars of calabrese, green sprouting broccoli, have been determined using glucose release and high performance liquid chromatographic methods. The levels of total glucosinolates (range, 42·1–94·5 mg 100 g⁻¹ fresh weight; mean, 62·3 mg 100 g⁻¹ fresh weight) were comparable with those reported previously for cauliflower, but lower than those found in cabbage and, especially, Brussels sprouts. Analysis of the individual components revealed the main species to be 4-methylsulphinylbutyl glucosinolate (glucoraphanin) and, particularly, glucobrassicin and neoglucobrassicin, containing 3-indolylmethyl and 1-methoxy-3-indolylmethyl side chains, respectively. The individual glucosinolate contents of calabrese and cauliflower are compared and differences are considered in the context of biosynthetic pathways. The consequences of these findings for the flavour and biological properties of calabrese are briefly discussed.     

Influence of blanching and freezing broccoli (<Emphasis Type="Italic">Brassica oleracea</Emphasis> var. <Emphasis Type="Italic">italica</Emphasis>) prior to storage and cooking on glucosinolate concentrations and myrosinase activity

Glucosinolates contribute to the chemoprotective effects of Brassica vegetables. The influence of blanching and freezing broccoli, followed by storage or cooking, on its glucosinolate concentration and myrosinase activity was investigated. Myrosinase activity was reduced by 93%, while glucosinolate concentration was unaltered after blanch-freezing broccoli. Blanch-frozen Brassica retained the glucosinolate content of its fresh counterpart after storage at T = −20 °C for up to 90 days. Fresh or blanch-frozen broccoli was stir-fried, boiled, boiled and kept hot for 2 h, or left uncooked. Stir-frying retained the highest glucosinolate concentration and myrosinase activity, regardless of pre-cooking. Boiling and keeping blanch-frozen broccoli hot completely denatured myrosinase and decreased glucosinolate concentration by 42%. Aromatic and indole glucosinolates were reduced to a larger extent than aliphatic glucosinolates, especially when boiled broccoli was kept hot. The final concentration of glucosinolates in Brassica is influenced by cooking, while the myrosinase activity is modified by pre-treatment and subsequent cooking.     

Variation of glucosinolates in three edible parts of Chinese kale (Brassica alboglabra Bailey) varieties

Glucosinolates in Chinese kale (Brassica alboglabra Bailey) were analysed by liquid chromatography–mass spectrometry (LC–MS), and the variation of glucosinolates in three edible parts (sprout, rosette leaf and bolting stem) of 27 Chinese kale varieties was investigated. Thirteen glucosinolates, including eight aliphatic glucosinolates, four indole glucosinolates and one aromatic glucosinolate, were identified in Chinese kale. The contents of total glucosinolate varied extensively among the different edible parts, and the total glucosinolate contents in the sprouts were obviously higher than those in rosette leaves and bolting stems. Obvious differences in the total and individual glucosinolate contents were also observed in each edible part among the different varieties. Gluconapin was the most abundant glucosinolate among all the edible parts of the 27 varieties except for the sprout of JL-26. The JL-26, JL-25 and JL-16 varieties are good candidates for future breeding programs since they contain high levels of methylsulphinylalkyl glucosinolates (glucoiberin and glucoraphanin) in certain edible parts.     

Effects of fruit bagging on anthocyanins, sugars, organic acids, and color properties of ‘Granny Smith’ and ‘Golden Delicious’ during fruit maturation

The effects of fruit bagging on anthocyanins, sugars, organic acids, and color properties of ‘Granny Smith’ and ‘Golden Delicious’ were investigated in this study. Young fruits were bagged 40 days after flowering (DAF) with paper bags. The bagged fruits of ‘Golden Delicious’ were uncovered and exposed to light 120 DAF, while those of ‘Granny Smith’ 160 DAF. The fruits were harvested after 0, 2, 4, 6, 8, 10, and 15 day of bag removal, respectively. The development of anthocyanins, sugars, organic acids, and color properties in the flesh of ‘Granny Smith’ and ‘Golden Delicious’ was determined. After bag removal, the ‘Granny Smith’ and ‘Golden Delicious’ turn red, a* was consequently augmented, while L*, b*, C*, and h⁰ reduced. Cyanidin 3-galactoside and cyaniding 3-arabinoside were identified in ‘Granny Smith’ and ‘Golden Delicious’ as the two constituents responsible for red color of apple peel, and with cyanidin 3-galactoside being the most abundant anthocyanin in these non-red cultivars. Fructose, sucrose, and sorbitol were the major sugars and sugar alcohol, and malic acid was the major organic acid. Concentrations of most sugars and all organic acids quickly increased during 0–4 DABR, suggesting that synthesis of these sugars and organic acids was inhibited by fruit bagging. Furthermore, the cy3-gal and cy3-ara accumulation of all tested cultivars was significantly correlated with sucrose, indicating that sucrose may be the more important factors in the biosynthesis of anthocyanin.