Impact of cold storage on glucosinolate levels in seed-sprouts of broccoli, rocket, white radish and kohl-rabi

Abstract

The effect of cold storage on glucosinolate concentration was examined in 7-day-old seed-sprouts of broccoli, kohl rabi, white radish and rocket. Principal glucosinolates identified were glucoraphanin and glucoerucin (in broccoli, kohl rabi and rocket), glucoiberin (in broccoli and kohl rabi), and glucoraphenin and glucodehydroerucin (in white radish). Generally, sprouts showed no significant changes in individual glucosinolate concentrations during storage at 4°C for 3 weeks. The exception to this was rocket, which showed a significant decline in glucoerucin and glucoraphanin after 1 and 2 weeks, respectively. These preliminary results indicate that as there is no significant loss of glucosinolates in broccoli, radish and kohl rabi sprouts, these sprouts may be stored under domestic refrigeration conditions without significant loss of potential anti-cancer compounds. Rocket sprouts, on the other hand, should be consumed soon after purchase if glucosinolate levels are to be maintained.

Stable, water extractable isothiocyanates from Moringa oleifera leaves attenuate inflammation in vitro

“…Preparation of MC using the blender was performed with three separate batches of moringa leaves and subjected to ITC quantification by LCMS to ensure reproducibility of the extraction method. The content of ITCs in MC (1.66%) is approximately 3 times higher than the SF content delivered in broccoli sprouts (calculated using a reported 61% conversion rate of glucoraphanin to SF and converted to dry weight factoring 89% moisture content (Force, O'Hare, Wong, & Irving, 2007;Pereira et al, 2002;Song & Thornalley, 2007)). MC, prepared in large batches, was subsequently evaluated for chemical stability of ITCs, total polyphenol content, oxygen radical absorbance capacity and anti-inflammatory activity in vitro.…”

Effect of domestic processing on bioactive compounds

“…Results indicate that these products may be stored under domestic refrigeration conditions without significant loss of potential anti-cancer compounds. Rocket sprouts, on the other hand, should be consumed soon after purchase (Force et al 2007). …”

Decreased sulforaphene concentration and reduced myrosinase activity of radish (Raphanus sativus L.) root during cold storage

“…The levels of the major GSLs in broccoli florets have been shown to decrease by 31% after 5 days of storage at 4 C and by 82% at 20 C (Rodrigues and Rosa, 1999;Toivonen and Forney, 2004;Jones et al, 2006). However, radish or broccoli sprouts showed no significant changes in the ITC content during cold storage at 4 C for 3 weeks (Force et al, 2007). By contrast, GSLs and the vitamin levels decreased more rapidly in rocket sprouts and kale leaves than in broccoli florets, cabbage sprouts, or radish sprouts (Force et al, 2007).…”