Broccoli Powder Research Articles

Effects of tomato and broccoli on the bone status of growing female rats with different levels of calcium intake

A total of 130 weanling female SD rats were allowed one week of adaptation before they were assigned into 13 treatment groups. The baseline group was killed at the beginning of the experiment. Groups A, B, C and D were fed the AIN93G diet containing 0.1% calcium; groups E, F, G and H were fed the AIN93G diet containing 0.25% calcium; and groups I, J, K and L were fed the AIN93G diet containing 0.5% calcium. Corn starch (20% of the diet) was replaced by tomato powder for groups B, F, and J; by broccoli powder for groups C, G and K; and by a 50:50 mixture of tomato and broccoli powders for groups D, H and L. The rats were fed the assigned diets for 8 weeks. Bone length, ash, calcium content and breaking strength became higher as dietary calcium concentration increased. Substitution of the corn starch by tomato and/or broccoli powders did not significantly affect the bone status of rats fed diets containing 0.25% or more of calcium. However, tomato and/or broccoli improved the bone status of rats fed diets containing 0.1% calcium. These results indicate that vegetables such as tomato and broccoli can have beneficial effects on bone when calcium intake is very low.

Impact of selenate treatment on broccoli glucosinolate profile and bioactivity

Selenium (Se)‐enriched broccoli has potent anticarcinogenic effects, which are suggested to be the result of changes in detoxification enzyme activity, induction of apoptosis, and inhibition of histone deacetylation (HDAC) and angiogenesis. We previously showed that feeding high‐Se broccoli powder (H‐SeB; 4.28 ppm) to male Copenhagen rats induced hepatic ethoxyresorufin‐O‐deethylase (EROD) and NAD(P)H:quinone oxidoreductase (NQO1) activity 1.6 and 1.9‐fold over low‐Se broccoli (L‐SeB; 0.25 ppm), respectively. To elucidate the relative role of Se in induction of these enzymes, mouse hepatoma Hepa‐1c1c7 cells were exposed to aqueous extracts of H‐SeB or L‐SeB. Extracts of H‐SeB increased EROD and NQO1 activity 2.7 and 1.3‐fold, respectively. Adding Se as selenite or Se‐methylselenocysteine (SeMSC) to L‐SeB extracts had no impact on EROD or QR activity. Likewise, Lee et al. reported that SeMSC up to 2.5 mM had no direct effect on HDAC in prostate cancer cells. Selenium‐enrichment of broccoli increased levels of the glucosinolate neoglucobrassicin, the hydrolysis product of which is known to induce EROD activity. We conclude that the increase in detoxification enzyme activity is not a direct effect of Se, but the result of a (plant) metabolite of Se and/or changes in the glucosinolate profile. Supported by grants from USDA/AFRI and the Illinois Council on Food and Agricultural Research.

Feeding Tomato and Broccoli Powders Enriched with Bioactives Improves Bioactivity Markers in Rats

Many studies have evaluated the cancer -preventive potential of individual bioactives from tomatoes and broccoli, but few have examined them within the context of a whole food. Male Copenhagen rats were fed diets containing 10% standard tomato powder, tomato enriched with lycopene or total carotenoids, standard broccoli floret, broccoli sprouts, or broccoli enriched with indole glucosinolates or selenium for 7 days. All broccoli diets increased the activity of colon quinone reductase (NQO1). Indole glucosinolate-enriched broccoli and selenium-enriched broccoli increased hepatic NQO1 and cytochrome P450 1A activity (P < 0.05). Standard broccoli and lycopene-enriched tomato diets down-regulated prostatic glutathione S-transferase P1 mRNA expression. Different tomato diets resulted in altered hepatic accumulation of lycopene, phytofluene, and phytoene. These results demonstrate that the bioactive content of vegetables affects both tissue content of bioactives and activity of detoxification enzymes. Enhancing bioactive content of tomatoes and broccoli may enhance efficacy in the prevention of prostate cancer.

Bioaccumulation of carotenoids and sulforaphane conjugates from tomato and broccoli powders with differing bioactive profiles

High consumption of tomatoes and cruciferous vegetables has been linked to decreased risk of prostate cancer. Previous studies have evaluated the cancer preventive potential of individual bioactives found in tomatoes and broccoli, but few have examined them within the context of a whole food. We determined bioavailability of carotenoids and sulforaphane from 3 tomato and 4 broccoli diets with differing bioactive compound profiles to assess their potential for future cancer trials. Male Copenhagen rats were pair fed diets containing 10% tomato powder, high lycopene tomato powder, high carotenoid tomato powder, broccoli floret powder, broccoli sprout powder, high indole‐3‐carbinol broccoli powder, or high selenium broccoli powder for 7 days. The high lycopene diet resulted in greater hepatic lycopene accumulation and lower levels of phytoene and phytofluene compared to standard tomato powder. In groups fed broccoli diets, sulforaphane N‐acetylcysteine conjugates were determined in urine. The broccoli sprout diet resulted in the highest level of urinary sulforaphane conjugates and a significantly greater recovery of 39.4%, compared to 5.1% from the broccoli floret diet. These results demonstrate differential bioavailability of carotenoids and sulforaphane from tomato and broccoli diets with varying bioactive profiles. Funded by the Illinois Council on Food and Agricultural Research CF071‐006‐4‐SEN.

A comparison of the bioavailability of sulforaphane from broccoli sprouts and a semi‐purified broccoli powder rich in glucoraphanin in healthy human males

Glucoraphanin (GP) from broccoli exhibits properties of cancer prevention only after hydrolysis to sulforaphane (SF) by the plant enzyme myrosinase. Four healthy males were each fed four meals containing different broccoli preparations: broccoli sprouts, a novel semi‐purified broccoli powder lacking myrosinase (GP‐powder), broccoli sprouts combined with GP‐powder (mix), and a control meal. During the following 24 h, SF recovery in urine was 80%, 50%, and 22% of the GP ingested from sprout, mix and GP‐powder meals, respectively. Recovery of SF was delayed significantly from GP‐powder (only 1/5 of total during the first 6 h), compared to the sprouts and mix meals (2/5 of total during the first 6 h). Preliminary plasma analysis of SF metabolites revealed a similar delayed appearance from the novel GP‐powder. Liver analysis showed no indication of toxicity of any treatment at 24 hours. Whereas these data indicate a higher effectiveness of broccoli sprouts, they also suggest a delayed or prolonged effect from consumption of the novel GP‐powder from broccoli. Supported by Caudill Seed Inc., Louisville, KY.

Combinations of Tomato and Broccoli Enhance Antitumor Activity in Dunning R3327-H Prostate Adenocarcinomas

The consumption of diets containing 5 to 10 servings of fruits and vegetables daily is the foundation of public health recommendations for cancer prevention, yet this concept has not been tested in experimental models of prostate cancer. We evaluated combinations of tomato and broccoli in the Dunning R3327-H prostate adenocarcinoma model. Male Copenhagen rats (n=206) were fed diets containing 10% tomato, 10% broccoli, 5% tomato plus 5% broccoli (5:5 combination), 10% tomato plus 10% broccoli (10:10 combination) powders, or lycopene (23 or 224 nmol/g diet) for approximately 22 weeks starting 1 month prior to receiving s.c. tumor implants. We compared the effects of diet to surgical castration (2 weeks before termination) or finasteride (5 mg/kg body weight orally, 6 d/wk). Castration reduced prostate weights, tumor areas, and tumor weight (62%, P<0.001), whereas finasteride reduced prostate weights (P<0.0001), but had no effect on tumor area or weight. Lycopene at 23 or 224 nmol/g of the diet insignificantly reduced tumor weights by 7% or 18%, respectively, whereas tomato reduced tumor weight by 34% (P<0.05). Broccoli decreased tumor weights by 42% (P<0.01) whereas the 10:10 combination caused a 52% decrease (P<0.001). Tumor growth reductions were associated with reduced proliferation and increased apoptosis, as quantified by proliferating cell nuclear antigen immunohistochemistry and the ApopTag assay. The combination of tomato and broccoli was more effective at slowing tumor growth than either tomato or broccoli alone and supports the public health recommendations to increase the intake of a variety of plant components.

Effects of diets containing lycopene, tomato, and/or broccoli upon tumor growth and biomarkers in the Dunning R3327‐H prostate adenocarcinoma model

The androgen-dependent Dunning R3327-H transplantable rat prostate adenocarcinoma model, in male Copenhagen rats, was utilized to examine dietary interventions on tumor growth and biomarkers. Diets were initiated 1 mo before tumor inoculation (20 mg of fresh tumor in Matrigel) and continued for ~18 wks. Rats showed similar food efficiency. Diets containing 10% broccoli (P <0.01), 10% of tomato and 10% broccoli (P <0.001), or following castration (P <0.001), had significantly reduced tumor weights compared to control tumors. A greater than 40% decrease in tumor weights was observed in the rats fed 10% broccoli, whereas a 52% decrease was seen in the 10% broccoli with 10% tomato combination group, and castration resulted in a 62% decrease. Those fed 10% tomato or the combination of 5% tomato and broccoli powders showed a trend for reduction in tumor weights, with an almost 30% decline in growth compared to the control (for both, P <0.06). The high lycopene diet (0.25 g of 5% lycopene beadlets/kg diet) did not significantly reduce tumor weight (P= 0.24). No physiologically relevant differences were seen in serum testosterone or dihydroxytestosterone concentrations. Blood and tissue samples were procured for assessment of biomarkers relevant to tumorigenesis using immunohistochemistry, gene expression via RT-PCR, and P450 activity assays. (Supported by AICR #01B061/ IFAFS #00-52101-9695)