The aim of this study was to evaluate the potential health benefits of onions consumed at two levels of intake, using the pig model. The dietary fat content was set at a level typical of a "western" diet (25% w/w). Fifteen female and fifteen male pigs (Large White x Landrace) were allocated to one of three dietary treatments in a randomised block design. Treatments consisted of control diet (no onion) and onion supplementation at either 8.6 or 21.4 g of onion/MJ DE fed for six weeks. Onion consumption reduced plasma triglyceride levels by 15% (P=0.030) regardless of sex and onion dose. Total plasma cholesterol and cholesterol fractions were unaffected by onion supplementation (P>0.050). The bioactivity of onion was evident in haematocrit measures, where red blood cell and haemoglobin were significantly reduced in a dose dependant manner (P<0.001 and P=0.011, respectively), while other cell counts, with exception of segmented neutrophils (-18%, P=0.012), were largely unaffected. Serum oxidative status was improved (P=0.007) in pigs consuming onions. These data demonstrate that consumption of onions can have positive health effects in both male and female pigs consuming a high fat diet.

The objective of this study was to determine the health benefits of extra-virgin and refined olive oils, which are high in mono-unsaturated fatty acids (MUFAs) and polyphenolic compounds using the pig as a model. Thirty-two cross-bred pigs were individually penned, allocated to one of four dietary treatments and fed ad libitum for 28 days. Two of the experimental diets consisted of a basal diet containing 12% tallow and either 7% sunflower oil (TSO) or 7% extra-virgin olive oil (TEVO) on a w/w basis. The remaining diets contained 19% extra-virgin olive oil (EVO) or 19% of refined olive oil (RO). On days 7, 14 and 28 fasted and 3-h post-prandial blood samples were taken. Body composition was measured at the beginning and end of the study using dual energy X-ray absorptiometry. Daily gain, feed intake and lean and fat deposition were not significantly different between the treatments. However, the daily increase in bone mineral density was higher in pigs fed diets containing olive oil (1.23 vs 2.54, 6.28, 5.20 mg cm−2 per day for TSO, TEVO, EVO and RO, respectively, P = 0.050). Both fasting and non-fasting plasma triglycerides were lower (P = 0.003) in pigs fed MUFA-rich diets, while the cholesterol profile was not significantly different between the treatments. The results from in vitro copper-induced lipid peroxidation, expressed in terms of conjugated dienes, showed that low density lipoprotein (LDL) particles in postprandial serum from pigs fed olive oil were moderately more resistant to oxidative modification. In conclusion, these data demonstrate that both extra-virgin and refined olive oils attenuate postprandial hypertriglyceridaemia, moderately affect oxidation susceptibility and increase bone mineral density in growing pigs. Copyright © 2006 Society of Chemical Industry

Three sulfur (S) treatements were imposed by applying gypsum to three broccoli cultivars (Claudia, Marathon, and TB-234) known to differ in glucoraphanin content of mature seeds. The S treatments were control (very low added S), low S (23 kg S ha(-)(1)), and high S (92 kg S ha(-)(1)). The gypsum applications during the early vegetative phase of the three broccoli cultivars increased S uptake and the glucoraphanin content in each plant organ. There were significant genotypic differences for the content of both S and glucoraphanin in all plant organs at different growth stages with gypsum applications. A large increase in S and glucoraphanin content was found in the green heads of broccoli and mature seeds. S present in glucoraphanin accounted for only 4-10% of total S content in broccoli heads. However, S present in glucoraphanin in mature seeds accounted for 40-46% of the total S in the seeds of moderate and high glucoraphanin cultivars (Marathon and TB-234). The partitioning of S into glucoraphanin also increased with gypsum applications. Differences in S uptake, S distribution between organs, and partitioning of S into glucoraphanin largely explained the differences in glucoraphanin content in the green heads and mature seeds for the three broccoli cultivars and three S treatments.

Distribution of sinigrin (2-propenylglucosinolate) and glucoraphanin (4-methylsulphinylbutylglucosinolate) concentration was determined in seeds and seedlings of Brassica species: B. oleracea, B. nigra, B. juncea, B. rapa and B. napus using a simple and reliable extraction method. Glucosinolates were extracted from seeds and seedlings using boiling water and were analysed by reverse phase ion-pair chromatography with UV detection. High concentrations of sinigrin were found in B. nigra, B. juncea var. rugosa (mustard greens) and B. oleracea (Brussels sprouts, cabbage, cauliflower, and Chinese broccoli). Sinigrin was absent from B. rapa and B. napus and was present in negligible concentrations in B. oleracea var. italica (broccoli). The concentration of sinigrin in the seed was similar to that in the cotyledon and hypocotyl tissues (7-day-old seedling) in most Brassica species tested. Glucoraphanin was found at high concentrations in B. oleracea var. italica and moderate concentrations in B. oleracea var. capitata (cabbage), whilst was absent in B. nigra, B. juncea, B. rapa and B. napus. Glucoraphanin concentration was between 44.2 and 274.1μmolg−1 DW among broccoli genotypes. Kalibrini®, a new hybrid line between broccoli and Chinese broccoli (kailan) contained a moderate concentration of glucoraphanin (145.3μmolg−1 DW) compared to its parent lines (274.1μmolg−1 DW in broccoli but only 1.2μmolg−1 DW in kailan). Glucoraphanin concentration in seedlings was significantly lower than that in the seed of broccoli while there was no significant difference in sinigrin concentration in seedlings of most Brassica species tested. The study has shown the extensive variability in sinigrin and glucoraphanin concentrations among Brassica species and genotypes that is available for selection and breeding. New elite lines can be produced for use as commercial crops in the health food or nutraceutical industries.

The effects of post-harvest and packaging treatments on glucoraphanin (4-methylsulfinylbutyl glucosinolate), the glucosinolate precursor of anticancer isothiocyanate sulforaphane [4-methylsulfinylbutyl isothiocyanate], were examined in broccoli (Brassica oleracea var. italica) during storage times. The results showed that at 20 degrees C, 55% loss of glucoraphanin concentration occurred in broccoli stored in open boxes during the first 3 days of the treatment and 56% loss was found in broccoli stored in plastic bags by day 7. Under both air and controlled atmosphere (CA) storage, glucoraphanin concentration appeared to fluctuate slightly during 25 days of storage and the concentrations under CA was significantly higher than those stored under air treatment. In modified atmosphere packaging (MAP) treatments, glucoraphanin concentration in air control packaging decreased significantly whereas there were no significant changes in glucoraphanin concentration in MAP with no holes at 4 degrees C and two microholes at 20 degrees C for up to 10 days. Decreases in glucoraphanin concentration occurred when the broccoli heads deteriorated. In the present study, the best method for preserving glucoraphanin concentration in broccoli heads after harvest was storage of broccoli in MAP and refrigeration at 4 degrees C. This condition maintained the glucoraphanin concentration for at least 10 days and also maintained the visual quality of the broccoli heads.

Hydrolysis products of sinigrin (2-propenylglucosinolate) and glucoraphanin (4-methylsulphinylbutylglucosinolate) have been shown to protect against the development of cancers. However, there was limited information available on the variation of these two glucosinolates throughout the plant cycle. The objective of this study was to evaluate sinigrin and glucoraphanin levels within Brassica plants during development. Sinigrin concentration in B. juncea and B. nigra decreased from seedling to early flowering stage, increased in the late flowering stage and then decreased again during seed maturation. The lowest concentration of sinigrin occurred at the early flowering stage except in one genotype of B. juncea (PI 179858). Sinigrin concentration also increased in maturing seeds while the concentration in pods decreased. The concentration of glucoraphanin in B. oleracea var. italica decreased from the start of seed germination to the flowering stages. The lowest concentration was also found at the flowering stage. A higher concentration of glucoraphanin was detected in the green broccoli heads and flower heads than in other reproductive tissues. However, the highest content of glucoraphanin occurred at the green head stage and then declined as flowering was initiated. These results have shown that green and brown seeds of mustards contained the highest concentration of sinigrin while the highest concentration of glucoraphanin occurred in young broccoli seedlings and seeds. This information should be useful for the development of those compounds as nutraceuticals.