ascorbic-acid and sulforaphane

Chemopreventive effects of broccoli, a highly valued vegetable, have been known for a long time. Several studies have demonstrated that broccoli might be beneficial by reducing the risk for the development of certain forms of cancer. These effects are generally attributed to glucosinolate-derived degradation products like isothiocyanates and indoles which are formed by the hydrolytic action of plant myrosinase and/or glucosidases deriving from the human microbial flora. However, recent in vitro and experimental animal studies indicate that broccoli, its extracts and the glucosinolate-derived degradation products might also have undesirable effects, especially genotoxic activities. However, the relevance of the genotoxic activities to human health is not known yet. This paper gives an overview on genotoxic, anti-genotoxic/chemopreventive, nutritive and antinutritive properties of broccoli, its ingredients and their degradation products. A qualitative comparison of the benefit and risk of broccoli consumption benefit-risk assessment shows that the benefit from intake in modest quantities and in processed form outweighs potential risks. For other preparations (fortified broccoli-based dietary supplements, diets with extraordinary high daily intake, consumption as a raw vegetable) further studies both for potential risks and beneficial effects are needed in order to assess the benefit and risk in the future.

Topics: Animals; Antineoplastic Agents; Ascorbic Acid; Brassica; DNA Damage; Glucosinolates; Glycoside Hydrolases; Humans; Indoles; Isothiocyanates; Models, Animal; Neoplasms; Plant Extracts; Risk Assessment; Sulfoxides; Thiocyanates; Vegetables

Urban pollution is correlated with an increased prevalence of skin pigmentation disorders, however the physiological processes underlying this association are unclear.. To delineate the relationship between polycyclic aromatic hydrocarbons (PAHs), a key constituent of atmospheric pollution, and immunity/skin pigmentation pathways.. We exposed peripheral blood mononuclear cells (PBMC) to PAHs and performed cytokines/chemokine profiling. We then examined the effect of immune activation on pigmentation by co-culturing PBMC and Benzo(a)pyrene (BaP) with reconstructed human pigmented epidermis (RHPE). To study the mechanism, we treated keratinocytes with conditioned medium from BaP-exposed PBMC and studied DNA damage responses, aryl hydrocarbon receptor (AhR) activation and pro-pigmentation factor, proopiomelanocortin (POMC) secretion.. PAHs induced up-regulation of inflammatory cytokines/chemokine in PBMC. Co-culturing of RHPE with PBMC+BaP resulted in increased melanin content and localization. BaP-conditioned medium significantly increased DNA damage, p53 stabilization, AhR activation and POMC secretion in keratinocytes. We found that IFNγ induced DNA damage, while TNFα and IL-8 potentiated POMC secretion in keratinocytes. Importantly, BaP-conditioned medium-induced DNA damage and POMC secretion is prevented by antioxidants vitamin E, vitamin C and sulforaphane, as well as the prototypical corticosteroid dexamethasone. Finally, vitamin C and sulforaphane enhanced the genome protective and depigmentation effects of dexamethasone, providing proof-of-concept for a combinatorial approach for the prevention and/or correction of PAH-induced pigment spots formation.. Our study reveals the importance of systemic immunity in regulating PAH-induced skin pigmentation, and provide a new keratinocyte DNA damage response mechanistic target for the prevention or reversal of pollution-associated skin pigmentation.

Topics: Anti-Inflammatory Agents; Antioxidants; Ascorbic Acid; Benzo(a)pyrene; Cells, Cultured; Coculture Techniques; Culture Media, Conditioned; Cytokines; Dexamethasone; DNA Damage; DNA Repair; Epidermis; Humans; Immune System Phenomena; Interferon-gamma; Interleukin-8; Isothiocyanates; Keratinocytes; Leukocytes, Mononuclear; Melanins; Polycyclic Aromatic Hydrocarbons; Pro-Opiomelanocortin; Receptors, Aryl Hydrocarbon; Skin Pigmentation; Sulfoxides; Tumor Necrosis Factor-alpha; Vitamin E

An integrated membrane process for the recovery and concentration of phytotherapeutics in broccoli juice was investigated to develop a natural product that could be of interest for food and/or pharmaceutical industry. Following a pretreatment step to remove suspended solids, the juice was ultrafiltered through a 50kDa MWCO polyethersulfone membrane. The permeate stream was further concentrated by osmotic distillation up to 42.6°Brix. During ultrafiltration, a complete recovery of sulforaphane, malic acid and citric acid was achieved, where total phenolic content and ascorbic acid were recovered at a ratio of 94.5 and 92.4%, respectively. All the bioactive compounds identified in broccoli juice was well preserved during subsequent 6-fold concentration by osmotic distillation. No significant difference was observed in total antioxidant activity of the juice throughout the operation. The proposed integrated membrane process has shown promising potential to produce a natural concentrate enriched in phytotherapeutics of the broccoli juice.

Topics: Ascorbic Acid; Brassica; Distillation; Food Handling; Fruit and Vegetable Juices; Isothiocyanates; Osmosis; Phenols; Sulfoxides; Ultrafiltration

Current evidence supports the positive association between the consumption of plant foods and health. In this work, we assessed the effect of consuming a half-serving (30 g) or one serving (60 g) of broccoli sprouts on the urinary concentrations of biomarkers of oxidative stress (isoprostanes) and inflammation (prostaglandins and thromboxanes). Twenty-four volunteers participated in the project. A quantitative determination of sulforaphane and its mercapturic derivatives, eicosanoids, and total vitamin C in urine was performed. The intake of broccoli sprouts produced an increase in the urinary concentrations of sulforaphane metabolites and vitamin C. Among the 13 eicosanoids analyzed, tetranor-PGEM and 11β-PGF2α as well as 11-dehydro-TXB2 showed a significant decrease in their urinary concentrations after the ingestion of broccoli sprouts. Therefore, the consumption of broccoli sprouts modulated the excretion of biomarkers linked to inflammation and vascular reactions without exerting a significant influence on the oxidation of phospholipids in vivo.

Topics: Adult; Ascorbic Acid; Biomarkers; Brassica; Chromatography, High Pressure Liquid; Cross-Over Studies; Female; Glucosinolates; Healthy Volunteers; Humans; Imidoesters; Inflammation; Isoprostanes; Isothiocyanates; Male; Middle Aged; Oxidative Stress; Oximes; Plant Extracts; Prostaglandins; Sulfoxides; Tandem Mass Spectrometry; Thromboxane B2; Vascular Diseases; White People; Young Adult

Health-promoting compounds, antioxidant and myrosinase activity in the sprouts of three broccoli cultivars under 40 mM, 80 mM and 160 mM NaCl were investigated. LangYan (LY) sprouts had the richest health-promoting compounds among the evaluated cultivars. Treatment of 40 mM and 80 mM NaCl significantly decreased the content of ascorbic acid and total phenolic as well as antioxidant activity, but did not affect glucoraphanin, sulforaphane and myrosinase activity compared to the control. However, 160 mM NaCl treatment significantly enhanced the level of total phenolic, glucoraphanin, sulforaphane, antioxidant and myrosinase activity, while significantly decreased ascorbic acid content. The results suggest that 160 mM NaCl treatment would enhance antioxidant activity and sulforaphane yield in broccoli sprouts. The health-promoting value of broccoli sprouts depends on plant genotype and could be affected by NaCl stress.

Topics: Antioxidants; Ascorbic Acid; Brassica; China; Down-Regulation; Functional Food; Glucosinolates; Glycoside Hydrolases; Imidoesters; Isothiocyanates; Oximes; Phenols; Plant Proteins, Dietary; Plant Shoots; Salinity; Species Specificity; Stress, Physiological; Sulfoxides; Up-Regulation

Nrf2 is a basic leucine zipper transcriptional activator essential for the coordinated transcriptional induction of phase-2 and antioxidant enzymes. Brassica vegetables contain phytochemicals including glucoraphanin, the precursor of sulforaphane (SFN) and glucobrassicin, the precursor of indole-3-carbinole (I3C) and ascorbigen (ABG). The degradation products SFN, I3C and ABG may be capable of inducing cytoprotective genes in skin. In this study, we tested the potency of SFN, ABG and I3C in affecting Nrf2-dependent gene expression in human keratinocytes in culture. SFN but not ABG and its precursors I3C and ascorbic acid induced Nrf2 dependent gene expression at a relatively low concentration (5 micromol/l). Induction of Nrf2 due to SFN was accompanied by an increase in mRNA and protein levels of NADPH quinone oxidoreductase 1, heme oxygenase 1 and gamma-glutamylcysteine-synthetase. Furthermore, SFN elevated cellular glutathione levels and antagonized tumor necrosis factor-alpha-induced NFkappaB transactivation. Therefore, SFN treatment may present a strategy for enhancing the cellular defense mechanisms in skin.

Topics: Anticarcinogenic Agents; Ascorbic Acid; Cells, Cultured; Gene Expression; Glutamate-Cysteine Ligase; Glutathione; Heme Oxygenase-1; Humans; Indoles; Isothiocyanates; Keratinocytes; NAD(P)H Dehydrogenase (Quinone); NF-E2-Related Factor 2; NF-kappa B; RNA, Messenger; Sulfoxides; Thiocyanates

In this work the effects of common household practices such as chilling, freezing, and cooking on vitamin C retention in broccoli (Marathon cv.), as well as their influence on the release of sulforaphane upon enzymatic hydrolysis of glucoraphanin by the endogenous enzyme myrosinase, were investigated. When chilled at 6 degrees C and 95% R.H. for 35 d, broccoli showed a vitamin C and sulforaphane loss of about 39% and 29%, respectively, while storage at -18 degrees C for 60 d resulted in similar losses, but mainly due to the blanching step. Boiling, steaming, microwaving, pressure-cooking, and the combined use of pressure and microwaves were the cooking methods investigated. Boiling and steaming caused significant vitamin C losses, 34% and 22%, respectively, while with the other treatments more than 90% retention was observed. Sulforaphane was no more detectable after boiling or steaming, while pressure/microwave cooking did not cause any significant loss. The quantitative distribution of these moieties in the florets and stems of fresh and chilled broccoli was also investigated.

Topics: Anticarcinogenic Agents; Antioxidants; Ascorbic Acid; Brassica; Cooking; Food Handling; Food Preservation; Food, Organic; Humans; Isothiocyanates; Microwaves; Nutritive Value; Pressure; Sulfoxides; Temperature; Thiocyanates; Time Factors