Evaluation of biological activities of raw and cooked Brassica oleracea sprout extracts rich in bioactive compound Sulforaphane

Background and Aims: Broccoli sprout extract (Brassica oleracea) has extensive biological activities that are mainly attributed to the presence of bioactive compounds, such as sulforaphane. This study aimed to investigate the antioxidant and antibacterial activities of cooked and raw extracts of broccoli sprouts. Materials and Methods: The amount of sulforaphane in broccoli sprout extract was evaluated by high-performance liquid chromatography (HPLC). Moreover, the amount of phenolic and flavonoid compounds and antioxidant capacity were investigated by the DPPH free radical scavenging method. In addition, the antibacterial activity of raw and cooked sprout extracts on some bacteria was explored using disk diffusion assay and minimum inhibitory concentration (MIC) by macro dilution method. Significant differences were analyzed by one-way analysis of variance (ANOVA) through Duncan's multiple range test. Results: Based on the results obtained by HPLC, the amount of sulforaphane in the raw broccoli sprout extract was determined to be 787.46 μg/mL. Moreover, the antioxidant activity of raw and cooked sprout extracts depicted a higher antioxidant activity with an increase in concentration. Furthermore, the antibacterial study showed that cooked sprout extract had higher antimicrobial activity, compared to the raw sprout extract (at a significance level of 0.05). The highest growth inhibition zone was found against Gram-positive Bacillus cereus strain with a diameter of 18±0.6 mm; moreover, the lowest amounts of MIC and MBC were obtained at 0.39 and 0.78 mg/mL, respectively. Conclusion: In general, the results show that cooked broccoli sprout extract has significant antioxidant and antibacterial activities, compared to the raw sprout. Accordingly, it can be utilized in food, health, and medical products as a highly promising source. However, further studies are required to be conducted in this regard.

Composition of the Gut Microbiome Influences Production of Sulforaphane-Nitrile and Iberin-Nitrile from Glucosinolates in Broccoli Sprouts

Isothiocyanates, such as sulforaphane and iberin, derived from glucosinolates (GLS) in cruciferous vegetables, are known to prevent and suppress cancer development. GLS can also be converted by bacteria to biologically inert nitriles, such as sulforaphane-nitrile (SFN-NIT) and iberin-nitrile (IBN-NIT), but the role of the gut microbiome in this process is relatively undescribed and SFN-NIT excretion in humans is unknown. An ex vivo fecal incubation model with in vitro digested broccoli sprouts and 16S sequencing was utilized to explore the role of the gut microbiome in SFN- and IBN-NIT production. SFN-NIT excretion was measured among human subjects following broccoli sprout consumption. The fecal culture model showed high inter-individual variability in nitrile production and identified two sub-populations of microbial communities among the fecal cultures, which coincided with a differing abundance of nitriles. The Clostridiaceae family was associated with high levels, while individuals with a low abundance of nitriles were more enriched with taxa from the Enterobacteriaceae family. High levels of inter-individual variation in urine SFN-NIT levels were also observed, with peak excretion of SFN-NIT at 24 h post broccoli sprout consumption. These results suggest that nitrile production from broccoli, as opposed to isothiocyanates, could be influenced by gut microbiome composition, potentially lowering efficacy of cruciferous vegetable interventions.

Factors Influencing Sulforaphane Content in Broccoli Sprouts and Subsequent Sulforaphane Extraction

Broccoli sprouts contain 10–100 times higher levels of sulforaphane than mature plants, something that has been well known since 1997. Sulforaphane has a whole range of unique biological properties, and it is especially an inducer of phase 2 detoxication enzymes. Therefore, its use has been intensively studied in the field of health and nutrition. The formation of sulforaphane is controlled by the epithiospecifier protein, a myrosinase co-factor, which is temperature-specific. This paper studies the influence of temperature, heating time, the addition of myrosinase in the form of Raphanus sativus sprouts in constant ratio to broccoli sprouts, and other technological steps on the final sulforaphane content in broccoli sprout homogenates. These technological steps are very important for preserving sulforaphane in broccoli sprouts, but there are some limitations concerning the amount of sulforaphane. We focused, therefore, on the extraction process, using suitable β-cyclodextrin, hexane and ethanol, with the goal of increasing the amount of sulforaphane in the final extract, thus stabilizing it and reducing the required amount sulforaphane needed, e.g., as a dietary supplement.

The Challenges of Designing and Implementing Clinical Trials With Broccoli Sprouts… and Turning Evidence Into Public Health Action

Broccoli sprouts are a convenient and rich source of the glucosinolate glucoraphanin, which can generate the chemopreventive agent sulforaphane through the catalytic actions of plant myrosinase or β-thioglucosidases in the gut microflora. Sulforaphane, in turn, is an inducer of cytoprotective enzymes through activation of Nrf2 signaling, and a potent inhibitor of carcinogenesis in multiple murine models. Sulforaphane is also protective in models of diabetes, neurodegenerative disease, and other inflammatory processes, likely reflecting additional actions of Nrf2 and interactions with other signaling pathways. Translating this efficacy into the design and implementation of clinical chemoprevention trials, especially food-based trials, faces numerous challenges including the selection of the source, placebo, and dose as well as standardization of the formulation of the intervention material. Unlike in animals, purified sulforaphane has had very limited use in clinical studies. We have conducted a series of clinical studies and randomized clinical trials to evaluate the effects of composition (glucoraphanin-rich [± myrosinase] vs. sulforaphane-rich or mixture beverages), formulation (beverage vs. tablet) and dose, on the efficacy of these broccoli sprout-based preparations to evaluate safety, pharmacokinetics, pharmacodynamic action, and clinical benefit. While the challenges for the evaluation of broccoli sprouts in clinical trials are themselves formidable, further hurdles must be overcome to bring this science to public health action.

The Effect of Broccoli Sprout Extract on Seasonal Grass Pollen-Induced Allergic Rhinitis

Patients exposed to pollutants are more likely to suffer from allergic rhinitis and may benefit from antioxidant treatment. Our study determined if patients diagnosed with grass-induced allergic rhinitis could benefit from broccoli sprout extract (BSE) supplementation. In total, 47 patients were confirmed with grass-induced allergic rhinitis and randomized to one of four groups: group 1 (nasal steroid spray + BSE), group 2 (nasal steroid spray + placebo tablet), group 3 (saline nasal spray + BSE) and group 4 (saline nasal spray + placebo tablet). Peak Nasal Inspiratory Flow (PNIF), Total Nasal Symptoms Scores (TNSS) and nasal mucus cytokine levels were analyzed in samples collected before and after the 3-week intervention. Comparing before and after the intervention, PNIF improved significantly when comparing Groups 1 and 2, vs. placebo, at various time points (p ≤ 0.05 at 5, 15, 60 and 240 min) following nasal challenge, while TNSS was only statistically significant at 5 (p = 0.03), 15 (p = 0.057) and 30 (p = 0.05) minutes. There were no statistically significant differences in various cytokine markers before and after the intervention. Combining nasal corticosteroid with BSE led to the most significant improvement in objective measures.

Broccoli sprout Sulforaphane affected hemodynamics and aorta myogenic spontaneous rhythmic contraction in sanitized water uptake mice

Drinking seawater erodes water source will lead to hemodynamic changes in cardiovascular system. The erosion affected vascular biomechanics further interrupt the blood supply in arterial network. In this study, we investigated the carotid arterial hemodynamics in salinity water fed mice, and the relative spontaneous contraction of aorta preparation. The biological effect of Broccoli sprout Sulforaphane was assessed in intake hemodynamic changes. Kunming mice were randomly divided into seawater feeding group, seawater + Sulforaphane group, freshwater feeding group, fresh water + Sulforaphane group. After 4 weeks of feeding, the pressure waveforms of common carotid artery were analyzed in vivo. The enhanced common carotid arterial pressures were calculated according to the breakpoint of systolic pressure rising phase. The ejection time was calculated according to the dicrotic notch. In vitro, the isolated aorta biomechanical features were tested on a micro stepping platform. The passive tension and relative myogenic spontaneous contraction were evaluated. The results indicated that in salinity water fed mice heart rate, ejection period were significantly accelerated. The systolic pressure breakpoint of the ascending phase was significantly increased; however, the central aortic pressure augment index was decreased. In vitro study, the isolated aorta preparations indicated remarkable myogenic spontaneous contraction in salinity water fed mice. The spontaneous contraction indicated a significant cycle pattern, the waveform cluster changes regularly in one cycle, maximal amplitude of myogenic autonomic contraction increased significantly. Spontaneous contraction became more active, however cycle duration shortened. In biological effect of Broccoli sprout supplement, Sulforaphane was effective in reducing the heart rate, prolonging ejection period, improving systolic pressure and pulse pressure amplitude in salinity water fed mice. We concluded that long-term salinity water uptake can form a new hypertension model in mice, which can affect the changes of carotid artery hemodynamics and local blood supply. The Broccoli sprout Sulforaphane can improve the high systolic blood pressure and ejection period of artery, and its mechanism needs further study.

Brokkoli bei Pankreaskarzinom – welche Dosis?

Lozanovski VJ, Polychronidis G, Gross W et al. Broccoli sprout supplementation in patients with advanced pancreatic cancer is difficult despite positive effects – results from the POUDER pilot study. Invest New Drugs 2019. doi:10.1007/s10637-019-00826-z