Evolution of important glucosinolates in three common Brassica vegetables during their processing into vegetable powder and in vitro gastric digestion

The Influence of Different Hydrothermal Processes Used in the Preparation of Brussels Sprouts on the Availability of Glucosinolates to Humans

Cruciferous vegetables represent a valuable source of bioactive compounds. However, there is currently a deficiency of information regarding the extent to which these compounds remain bioaccessible to the body following thermal treatment and digestion processes within the digestive tract. Accordingly, the aim of this study was to evaluate the impact of heat treatment and in vitro digestion on the level of selected bioactive compounds in Brussels sprouts. The Brussels sprouts samples were subjected to a range of thermal processing techniques, which were then followed by a simulated in vitro digestion. The investigated compounds were analyzed using UV-Vis spectrometry and liquid chromatography coupled with mass spectrometry (LC-MS). The findings revealed that the sous-vide method of cooking Brussels sprouts resulted in significantly higher losses of glucosinolates (GLS) in comparison to conventional cooking methods. No significant differences were observed with regard to isothiocyanates and indoles. The analysis of GLS following digestion revealed that the process was more effective after sous vide and traditional cooking, and slightly less effective after steam cooking. With regard to individual compounds, glucoraphanin (GRA), glucoraphenin (GIV), and gluconasturtiin (GNS) were found to be completely degraded, whereas methoxyglucobrassicin (metGBS) was the most resistant to digestion in both the sous vide and steamed Brussels sprouts. The results indicated that the process of simulating digestion had no significant impact on isothiocyanates and indoles. This suggests that, if present in the heat-treated samples, these compounds remained stable during the in vitro digestion procedure.

Unveiling the Nutritional Veil of Sulforaphane: With a Major Focus on Glucose Homeostasis Modulation

Abnormal glucose homeostasis is associated with metabolic syndromes including cardiovascular diseases, hypertension, type 2 diabetes mellitus, and obesity, highlighting the significance of maintaining a balanced glucose level for optimal biological function. This highlights the importance of maintaining normal glucose levels for proper biological functioning. Sulforaphane (SFN), the primary bioactive compound in broccoli from the Cruciferae or Brassicaceae family, has been shown to enhance glucose homeostasis effectively while exhibiting low cytotoxicity. This paper assesses the impact of SFN on glucose homeostasis in vitro, in vivo, and human trials, as well as the molecular mechanisms that drive its regulatory effects. New strategies have been proposed to enhance the bioavailability and targeted delivery of SFN in order to overcome inherent instability. The manuscript also covers the safety evaluations of SFN that have been documented for its production and utilization. Hence, a deeper understanding of the favorable influence and mechanism of SFN on glucose homeostasis, coupled with the fact that SFN is abundant in the human daily diet, may ultimately offer theoretical evidence to support its potential use in the food and pharmaceutical industries.

Comparative analysis of isothiocyanates in eight cruciferous vegetables and evaluation of the hepatoprotective effects of 4-(methylsulfinyl)-3-butenyl isothiocyanate (sulforaphene) from daikon radish (Raphanus sativus L.) sprouts

The contributions of cruciferous vegetables to human health are widely recognised, particularly at the molecular level, where their isothiocyanates play a significant role. However, compared to the well-studied isothiocyanate 4-(methylsulfinyl)butyl isothiocyanate (sulforaphane) produced from broccoli sprouts, less is known about the pharmacological effects of other isothiocyanates and the stage of vegetables preferable to obtain their benefits. We analysed the quantity and quality of isothiocyanates produced in both the sprouts and mature stages of eight cruciferous vegetables using gas chromatography-mass spectrometry (GC-MS). Additionally, we investigated the hepatoprotective effects of isothiocyanates in a mouse model of acute hepatitis induced by carbon tetrachloride (CCl4). Furthermore, we explored the detoxification enzyme-inducing activities of crude sprout extracts in normal rats. Among the eight cruciferous vegetables, daikon radish (Raphanus sativus L.) sprouts produced the highest amount of isothiocyanates, with 4-(methylsulfinyl)-3-butenyl isothiocyanate (sulforaphene) being the dominant compound. The amount of sulforaphene in daikon radish sprouts was approximately 30 times that of sulforaphane in broccoli sprouts. Sulforaphene demonstrated hepatoprotective effects similar to sulforaphane in ameliorating CCl4-induced hepatic injury in mice. A crude extract of 3-day-old daikon radish sprouts upregulated the detoxifying enzyme glutathione S-transferase (GST) in the liver, whereas the crude extract of broccoli sprouts showed limited upregulation. This study highlights that daikon radish sprouts and sulforaphene have the potential to serve as functional food materials with hepatoprotective effects. Furthermore, daikon radish sprouts may exhibit more potent hepatoprotective effects compared to broccoli sprouts.

Evidence on the Bioaccessibility of Glucosinolates and Breakdown Products of Cruciferous Sprouts by Simulated In Vitro Gastrointestinal Digestion

Cruciferous vegetables are gaining importance as nutritious and sustainable foods, rich in phytochemical compounds such as glucosinolates (GSLs). However, the breakdown products of these sulfur-based compounds, mainly represented by isothiocyanates (ITC) and indoles, can contribute to human health. In the human digestive system, the formation of these compounds continues to varying extents in the different stages of digestion, due to the contact of GSLs with different gastric fluids and enzymes under the physicochemical conditions of the gastrointestinal tract. Therefore, the aim of the present work was to uncover the effect of gastrointestinal digestion on the release of glucosinolates and their transformation into their bioactive counterparts by applying a simulated in vitro static model on a range of brassica (red radish, red cabbage, broccoli, and mustard) sprouts. In this sense, significantly higher bioaccessibility of ITC and indoles from GSLs of red cabbage sprouts was observed in comparison with broccoli, red radish, and mustard sprouts, due to the aliphatic GSLs proportion present in the different sprouts. This indicates that the bioaccessibility of GSLs from Brasicaceae sprouts is not exclusively associated with the initial content of these compounds in the plant material (almost negligible), but also with the release of GSLs and the ongoing breakdown reactions during the gastric and intestinal phases of digestion, respectively. Additionally, aliphatic GSLs provided higher bioaccessibility of their corresponding ITC in comparison to indolic and aromatic GSLs.