Basis for the new challenges of growing broccoli for health in hydroponics

Abstract

BACKGROUND: Variations in the contents of phytochemicals with biological activity in broccoli could originate as a result of genetic and environmental factors. An understanding of the effects of growth conditions on the bioactive compounds in broccoli is essential for improving its quality and nutritive value. Using salinity (40 mmol L −1 NaCl), and foliar sprayed compounds (methionine, tryptophan and chitosan) as different stress conditions, broccoli developed in soilless culture in the greenhouse was analysed for biologically active phytochemicals (glucosinolates, caffeoyl-quinic, ferulic and sinapic derivatives and vitamin C).

Natural Antioxidants in Purple Sprouting Broccoli under Mediterranean Climate

“…It is known that climatic factors, principally temperature, have a strong influence on vitamin C. Bumgarner and others (2012) showed that vegetables contained more vitamin C when grown under cool temperatures than hot temperatures. Thus, the amount of vitamin C could be lower under these experimental conditions (higher temperatures), and therefore, the variations in vitamin C content observed in the present work might be related to the combination of genetic and environmental factors as previously reported (Podsedek 2007; Moreno and others 2008). …”

“…Total vitamin C, as the sum of ascorbic acid (AA) and dehydroascorbic acid (DHAA), was determined according to Moreno and others (2008). The DHAA and AA contents were expressed as mg per 100 g fresh weight (FW) of vitamin C.…”

“…Previous works have shown that the nutritive quality and crop performance of broccoli is affected by genotype (Schönhof and others 2004; West and others 2004; Charron and others 2005), climatic conditions, and ecophysiological factors (Jeffery and others 2003; Abercrombie and others 2005; Moreno and others 2008). In fact, adverse environmental conditions force plants to minimize water loss through transpiration, by means of stomatal closure, but this can reduce growth since it depends on the ability to maintain a high photosynthetic rate (Koyro 2006; Lopez‐Berenguer and others 2006) and also high concentration of minerals and phytochemicals of added value of the food.…”

Improving the phytochemical composition of broccoli sprouts by elicitation

“…Moreover the aminoacids or chitosan solutions applied did not significantly increase the flavonoid, sinapic and ferulic acid derivatives content when compared to the control sprouts (Tables 1 and 2). In contrast, Moreno et al (2008) determined significant increases in the flavonoid content of broccoli inflorescences, by 45%, 30% and 52% after the application of 200 mM methionine, 200 mM tryptophan and 1 gl À1 chitosan, respectively; although in that experiment plants were subjected to saline abiotic stress that could be a key factor to the metabolic response observed.…”

“…As previously found in broccoli inflorescences and buckwheat seedlings (Kim et al, 2008;Moreno, Ló pez-Berenguer, Marti´nez-Ballesta, Carvajal, & Garci´a-Viguera, 2008), flavonoids were the most abundant phenolic class detected in the broccoli sprouts, accounting for over 70% of the total phenolic content, depending on the treatment applied and the sprout age. Brassica species have been shown to contain quercetin and kaempferol as the main flavonoid compounds, confirming the two major flavonol glycosides quercetin 3-O-sophoroside and kaempferol 3-O-sophoroside (Vallejo, Tomás-Barberán, & Ferreres, 2004).…”