Microbiota: a mediator to transform glucosinolate precursors in cruciferous vegetables to the active isothiocyanates

Strategy for preparing of glucosinolate derivatives with outstanding functional activities based on myrosinase

Glucosinolates are a class of sulfur- and nitrogen-containing secondary metabolites that are widely present in cruciferous vegetables. Degradation products of glucosinolate, glucosinolate derivatives such as sulforaphane, sulforaphene, and iberin, have garnered interest due to their promising functional activities including anticancer, antioxidant, and antibacterial activities. As a result, these glucosinolate derivatives have substantial implications in the realms of food, medicine, and agriculture. Among the methods for preparing glucosinolate derivatives, enzymatic approach based on myrosinase stands out as a greener and more efficient alternative to chemical synthesis, underscoring the scientific and practical significance of developing myrosinase with high catalytic activity. This paper provides a systematic overview of the origin, catalytic properties, and catalytic mechanism of the key myrosinase applied for glucosinolate derivatives preparation. Meanwhile, the glucosinolate derivatives prepared via myrosinase and their functional activities are also illustrated and discussed. Furthermore, it also anticipates future research directions in myrosinase and glucosinolate derivatives.

Exploring the bioaccessibility, in vitro colonic fermentation, and the impact on the intestinal microbiota of allyl-and benzyl-isothiocyanate from white and Ethiopian mustard

The aim of this research was to study the formation and bioaccessibility of allyl- and benzyl-isothiocyanate (ITC) resulting from the gastrointestinal digestion (small and large intestine) of green parts from Ethiopian and white mustard. In addition, a GC-MS methodology was validated to determine these compounds in bioaccessible and non-bioaccessible fraction. Plant clumps were divided into two batches: fresh and freeze-dried samples. ITC bioaccessibility was low in the small intestine, with values ranged between 11 and 53 % and mean values of 26 %. These results are in agreement with the fact that ITCs are poorly water-soluble compounds. Bioaccessibility values for lyophilised samples were lower than those obtained in fresh samples. This could be due to the degradation of the precursor glucosinolates (sinigrin and glucotropaeolin respectively). The simulation of the colonic fermentation reduced allyl - and benzyl - ITC levels from the non-bioaccessible fraction of Ethiopian and white mustard (values between 0.009 and 0.087 mg/g). In both cases, ITCs concentration dropped dramatically, i.e. with a ten-fold reduction. Nevertheless, this result does not necessarily indicate that ITCs have not been produced in the large intestine. Bacterial microbiota plays a key role in generating ITCs; however, ITCs are not always the final products of this process. The metagenomic analysis of colonic samples revealed that ITCs and cruciferous matrix significantly influenced the composition of gut microbiota, inhibiting potentially pathogenic bacteria such as Enterobacter and Klebsiella, while promoting beneficial bacteria such as Bifidobacterium, Faecalibacterium, Blautia, and Ruminococcus. Interestingly, ITCs-rich environments selected bacterial species (i.e. Enterobacter ludwigii) and promoted metabolic pathways involved in glucosinolate/ITCs metabolism.

Glucoraphanin and sulforaphane mitigate TNFα-induced Caco-2 monolayers permeabilization and inflammation

Intestinal permeabilization is central to the pathophysiology of chronic gut inflammation. This study investigated the efficacy of glucoraphanin (GR), prevalent in cruciferous vegetables, particularly broccoli, and its derivative sulforaphane (SF), in inhibiting tumor necrosis factor alpha (TNFα)-induced Caco-2 cell monolayers inflammation and permeabilization through the regulation of redox-sensitive events. TNFα binding to its receptor led to a rapid increase in oxidant production and subsequent elevation in the mRNA levels of NOX1, NOX4, and Duox2. GR and SF dose-dependently mitigated both these short- and long-term alterations in redox homeostasis. Downstream, GR and SF inhibited the activation of the redox-sensitive signaling cascades NF-κB (p65 and IKK) and MAPK ERK1/2, which contribute to inflammation and barrier permeabilization. GR (1 μM) and SF (0.5-1 μM) prevented TNFα-induced monolayer permeabilization and the associated reduction in the levels of the tight junction (TJ) proteins occludin and ZO-1. Both GR and SF also mitigated TNFα-induced increased mRNA levels of the myosin light chain kinase, which promotes TJ opening. Molecular docking suggests that although GR is mostly not absorbed, it could interact with extracellular and membrane sites in NOX1. Inhibition of NOX1 activity by GR would mitigate TNFα receptor downstream signaling and associated events. These findings support the concept that not only SF, but also GR, could exert systemic health benefits by protecting the intestinal barrier against inflammation-induced permeabilization, in part by regulating redox-sensitive pathways. GR has heretofore not been viewed as a biologically active molecule, but rather, the benign precursor of highly active SF. The consumption of GR and/or SF-rich vegetables or supplements in the diet may offer a means to mitigate the detrimental consequences of intestinal permeabilization, not only in disease states but also in conditions characterized by chronic inflammation of dietary and lifestyle origin.

Profiles of volatile sulfur compounds in various vegetables consumed in Korea using HS-SPME-GC/MS technique

Volatile sulfur compounds (VSCs) are not only important for their therapeutic potential but also significantly influence the flavor profiles of agricultural products. VSCs exhibit various chemical structures due to their stability and volatility, and they may form or be altered as a result of enzymatic and chemical reactions during storage and cooking. This study has focused on profiles of VSCs in 58 different vegetable samples by using HS-SPME-GC/MS technique and chemometric analyses. The validation was carried out using cabbage juice as a vegetable matrix for VSCs analysis, showing satisfactory repeatability (RSD 8.07% ~ 9.45%), reproducibility (RSD 4.22% ~ 7.71%), accuracy and specificity. The established method was utilized on various vegetables, revealing that 21 VSCs such as sulfides, disulfides, trisulfides, isothiocyanates, sulfhydryls, and thiophenes were successfully identified and quantified. These compounds were found in a range of vegetables including Allium species, Cruciferae, Capsicum species, green leafy vegetables, and mushrooms. In particular, isocyanate and allyl groups were abundant in Cruciferae and Allium vegetables, respectively. Cooking conditions were shown to reduce the levels of certain sulfur compounds such as dimethyl sulfide and dimethyl trisulfide in vegetables like broccoli and cabbage, suggesting that heat treatment can lead to the volatilization and reduction of these compounds. The present study provides reliable insights into the compositions of VSCs in various vegetables and examines the changes induced by different cooking methods.

Bioactive sulforaphane from cruciferous vegetables: advances in biosynthesis, metabolism, bioavailability, delivery, health benefits, and applications

Chronic inflammation-induced diseases (CID) are the dominant cause of death worldwide, contributing to over half of all global deaths. Sulforaphane (SFN) derived from cruciferous vegetables has been extensively studied for its multiple functional benefits in alleviating CID. This work comprehensively reviewed the biosynthesis, metabolism, bioavailability, delivery, health benefits, and applications of SFN and its potential mechanisms against CID (e.g., cancer, obesity, type 2 diabetes, et al.), and neurological disorders based on a decade of research. SFN exerts its biological functions through the hydrolysis of glucosinolates by gut microbiota, and exhibits rapid metabolism and excretion characteristics via metabolization of mercapturic acid pathway. Microencapsulation is an important way to improve the stability and targeted delivery of SFN. The health benefits of SNF against CID are attributed to the multiple regulatory mechanisms including modulating oxidative stress, inflammation, apoptosis, immune response, and intestinal homeostasis. The clinical applications of SFN and related formulations show promising potential; however, further exploration is required regarding the sources, dosages, toxicity profiles, and stability of SFN. Together, SFN is a natural product with great potential for development and application, which is crucial for the development of functional food and pharmaceutical industries.

Current Knowledge on the Preparation and Benefits of Cruciferous Vegetables as Relates to In Vitro, In Vivo, and Clinical Models of Inflammatory Bowel Disease

Inflammatory bowel disease is a chronic condition with a significant economic and social burden. The disease is complex and challenging to treat because it involves several pathologies, such as inflammation, oxidative stress, dysbiosis, and intestinal damage. The search for an effective treatment has identified cruciferous vegetables and their phytochemicals as potential management options for inflammatory bowel disease because they contain prebiotics, probiotics, and anti-inflammatory and antioxidant metabolites essential for a healthy gut. This critical narrative style review provides a robust insight into the pharmacological effects and benefits of crucifers and their documented bioactive compounds in in vitro and in vivo models, as well as clinical inflammatory bowel disease. The review highlights the significant impact of crucifer preparation and the presence of glucosinolates, isothiocyanates, flavonoids, and polyphenolic compounds, which are essential for the anti-inflammatory and antioxidative benefits of cruciferous vegetables, as well as their ability to promote the healthy microbial community and maintain the intestinal barrier. This review may serve as a viable nutritional guide for future research on methods and features essential to developing experiments, preventions, and treatments for inflammatory bowel disease. There is limited clinical information and future research may utilize current innovative tools, such as metabolomics, for adequate knowledge and effective translation into clinical therapy.

Investigating the Influence of Gut Microbiota-related Metabolites in Gastrointestinal Cancer

Gastrointestinal (GI) cancer is a major health concern due to its prevalence, impact on well-being, high mortality rate, economic burden, and potential for prevention and early detection. GI cancer research has made remarkable strides in understanding biology, risk factors, and treatment options. An emerging area of research is the gut microbiome's role in GI cancer development and treatment response. The gut microbiome, vital for digestion, metabolism, and immune function, is increasingly linked to GI cancers. Dysbiosis and alterations in gut microbe composition may contribute to cancer development. Scientists study how specific bacteria or microbial metabolites influence cancer progression and treatment response. Modulating the gut microbiota shows promise in enhancing treatment efficacy and preventing GI cancers. Gut microbiota dysbiosis can impact GI cancer through inflammation, metabolite production, genotoxicity, and immune modulation. Microbes produce metabolites like short-chain fatty acids, bile acids, and secondary metabolites. These affect host cells, influencing processes like cell proliferation, apoptosis, DNA damage, and immune regulation, all implicated in cancer development. This review explores the latest research on gut microbiota metabolites and their molecular mechanisms in GI cancers. The hope is that this attempt will help in conducting other relevant research to unravel the precise mechanism involved, identify microbial signatures associated with GI cancer, and develop targets.

Brassica-derived isothiocyanates as anticancer therapeutic agents and their nanodelivery

The isothiocyanates (ITCs) derived from the precursor glucosinolate molecules present in Brassica vegetables are bioactive organo-sulfur compounds with numerous pharmacologically important properties such as antioxidant, antiinflammatory, antimicrobial, and anticancer. Over the years, ITCs have been the focus of several research investigations associated with cancer treatment. Due to their potent chemo-preventive action, ITCs have been considered to be promising therapeutics for cancer therapy in place of the already existing conventional anticancer drugs. However, their wide spread use at the clinical stage is greatly restricted due to several factors such as low solubility in an aqueous medium, low bioavailability, low stability, and hormetic effect. To overcome these hindrances, nanotechnology can be exploited to develop nano-scale delivery systems that have the potential to enhance stability, and bioavailability and minimize the hermetic effect of ITCs.

Sulforaphane decreases serum selenoprotein P levels through enhancement of lysosomal degradation independent of Nrf2

Selenoprotein P (SeP) is a major selenoprotein in serum predominantly produced in the liver. Excess SeP impairs insulin secretion from the pancreas and insulin sensitivity in skeletal muscle, thus inhibition of SeP could be a therapeutic strategy for type 2 diabetes. In this study, we examine the effect of sulforaphane (SFN), a phytochemical of broccoli sprouts and an Nrf2 activator, on SeP expression in vitro and in vivo. Treatment of HepG2 cells with SFN decreases inter- and intra-cellular SeP levels. SFN enhances lysosomal acidification and expression of V-ATPase, and inhibition of this process cancels the decrease of SeP by SFN. SFN activates Nrf2 in the cells, while Nrf2 siRNA does not affect the decrease of SeP by SFN or lysosomal acidification. These results indicate that SFN decreases SeP by enhancing lysosomal degradation, independent of Nrf2. Injection of SFN to mice results in induction of cathepsin and a decrease of SeP in serum. The findings from this study are expected to contribute to developing SeP inhibitors in the future, thereby contributing to treating and preventing diseases related to increased SeP.

Therapeutic potential of sulforaphane in liver diseases: a review

The burden of liver diseases such as metabolic-associated fatty liver diseases and hepatocellular carcinoma has increased rapidly worldwide over the past decades. However, pharmacological therapies for these liver diseases are insufficient. Sulforaphane (SFN), an isothiocyanate that is mainly found in cruciferous vegetables, has been found to have a broad spectrum of activities like antioxidation, anti-inflammation, anti-diabetic, and anticancer effects. Recently, a growing number of studies have reported that SFN could significantly ameliorate hepatic steatosis and prevent the development of fatty liver, improve insulin sensitivity, attenuate oxidative damage and liver injury, induce apoptosis, and inhibit the proliferation of hepatoma cells through multiple signaling pathways. Moreover, many clinical studies have demonstrated that SFN is harmless to the human body and well-tolerated by individuals. This emerging evidence suggests SFN to be a promising drug candidate in the treatment of liver diseases. Nevertheless, limitations exist in the development of SFN as a hepatoprotective drug due to its special properties, including instability, water insolubility, and high inter-individual variation of bioavailability when used from broccoli sprout extracts. Herein, we comprehensively review the recent progress of SFN in the treatment of common liver diseases and the underlying mechanisms, with the aim to provide a better understanding of the therapeutic potential of SFN in liver diseases.

Dietary glucosinolates derived isothiocyanates: chemical properties, metabolism and their potential in prevention of Alzheimer's disease

Alzheimer's disease (AD) is the most prevalent form of dementia affecting millions of people worldwide. It is a progressive, irreversible, and incurable neurodegenerative disorder that disrupts the synaptic communication between millions of neurons, resulting in neuronal death and functional loss due to the abnormal accumulation of two naturally occurring proteins, amyloid β (Aβ) and tau. According to the 2018 World Alzheimer's Report, there is no single case of an Alzheimer's survivor; even 1 in 3 people die from Alzheimer's disease, and it is a growing epidemic across the globe fruits and vegetables rich in glucosinolates (GLCs), the precursors of isothiocyanates (ITCs), have long been known for their pharmacological properties and recently attracted increased interest for the possible prevention and treatment of neurodegenerative diseases. Epidemiological evidence from systematic research findings and clinical trials suggests that nutritional and functional dietary isothiocyanates interfere with the molecular cascades of Alzheimer's disease pathogenesis and prevent neurons from functional loss. The aim of this review is to explore the role of glucosinolates derived isothiocyanates in various molecular mechanisms involved in the progression of Alzheimer's disease and their potential in the prevention and treatment of Alzheimer's disease. It also covers the chemical diversity of isothiocyanates and their detailed mechanisms of action as reported by various in vitro and in vivo studies. Further clinical studies are necessary to evaluate their pharmacokinetic parameters and effectiveness in humans.

Effects of Glucosinolate-Enriched Red Radish (Raphanus sativus) on In Vitro Models of Intestinal Microbiota and Metabolic Syndrome-Related Functionalities

The gut microbiota profile is determined by diet composition, and therefore this interaction is crucial for promoting specific bacterial growth and enhancing the health status. Red radish (Raphanus sativusL.) contains several secondary plant metabolites that can exert a protective effect on human health. Recent studies have shown that radish leaves have a higher content of major nutrients, minerals, and fiber than roots, and they have garnered attention as a healthy food or supplement. Therefore, the consumption of the whole plant should be considered, as its nutritional value may be of greater interest. The aim of this work is to evaluate the effects of glucosinolate (GSL)-enriched radish with elicitors on the intestinal microbiota and metabolic syndrome-related functionalities by using an in vitro dynamic gastrointestinal system and several cellular models developed to study the GSL impact on different health indicators such as blood pressure, cholesterol metabolism, insulin resistance, adipogenesis, and reactive oxygen species (ROS). The treatment with red radish had an influence on short-chain fatty acids (SCFA) production, especially on acetic and propionic acid and many butyrate-producing bacteria, suggesting that consumption of the entire red radish plant (leaves and roots) could modify the human gut microbiota profile toward a healthier one. The evaluation of the metabolic syndrome-related functionalities showed a significant decrease in the gene expression of endothelin, interleukin IL-6, and cholesterol transporter-associated biomarkers (ABCA1 and ABCG5), suggesting an improvement of three risk factors associated with metabolic syndrome. The results support the idea that the use of elicitors on red radish crops and its further consumption (the entire plant) may contribute to improving the general health status and gut microbiota profile.

Chemical composition of extracts from leaves, stems and roots of wasabi (Eutrema japonicum) and their anti-cancer, anti-inflammatory and anti-microbial activities

The purpose of our study was to evaluate the composition of the extracts obtained from the roots and leaves of Eutrema japonicum cultivated in Poland. For this purpose, LC-DAD-IT-MS and LC-Q-TOF-MS analyses were used. The results revealed the presence of forty-two constituents comprising glycosinolates, phenylpropanoid glycosides, flavone glycosides, hydroxycinnamic acids, and other compounds. Then, the resultant extracts were subjected to an assessment of the potential cytotoxic effect on human colon adenocarcinoma cells, the effect on the growth of probiotic and intestinal pathogenic strains, as well as their anti-inflammatory activity. It was demonstrated that 60% ethanol extract from the biennial roots (WR2) had the strongest anti-inflammatory, antibacterial, and cytotoxic activities compared to the other samples. Our results suggest that extracts from E. japonicum may be considered as a promising compound for the production of health-promoting supplements.

Pharmacological evaluation of the anxiolytic-like effects of an aqueous extract of the Raphanus sativus L. sprouts in mice

Raphanus sativus L. (Brassicaceae), commonly known as radish, is consumed worldwide as a vegetable. However, its benefits on mental health are unknown. The aim of this study was to evaluate its anxiolytic-like effects and safety using different experimental models. An aqueous extract of R. sativus sprouts (AERSS) was pharmacologically evaluated by intraperitoneal route (i.p.) at 10, 30, and 100 mg/kg and orally (p.o.) at 500 mg/kg on behavior by using open-field and plus-maze tests. In addition, its acute toxicity (LD₅₀) was determined by the Lorke's method. Diazepam (1 mg/kg, i.p.) and buspirone (4 mg/kg, i.p.) were the reference drugs. A significant and anxiolytic-like dosage of AERSS (30 mg/kg, i.p.) resembling the effects of reference drugs was chosen to explore the involvement of GABA_A/BDZs site (flumazenil, 5 mg/kg, i.p.) and serotonin 5-HT_1A receptors (WAY100635, 1 mg/kg, i.p.) as a possible mechanism of action. A 500 mg/kg, p.o. dosage of AERSS produced an anxiolytic-like response equivalent to 100 mg/kg, i.p. No acute toxicity was observed since a LD₅₀ > 2000 mg/kg, i.p. The phytochemical analysis allowed the identification and quantification of major presence of sulforaphene (2500 µM), sulforaphane (15 µM), iberin (0.75 µM), and indol-3-carbinol (0.75 µM), as major constituents. Both the GABA_A/BDZs site and serotonin 5-HT_1A receptors were involved in the anxiolytic-like activity of AERSS, depending on the pharmacological parameter or the experimental assay tested. Our results demonstrate that the anxiolytic activity of R. sativus sprouts involves GABA_A/BDZs site and serotonin 5-HT_1A receptors supporting its health benefits in the treatment of anxiety beyond the satisfaction of basic nutritional needs.

Analysis of the microbial community structure and flavor components succession during salt-reducing pickling process of zhacai (preserved mustard tuber)

The salt-reducing pickling method has been applied to the industrial production of zhacai. In order to reveal the succession of the microbial community structure and flavor components during the pickling process, this study used PacBio Sequel to sequence the full length of 16S rRNA (bacteria, 1400 bp) and ITS (fungi, 1200 bp) genes, and detected flavor components simultaneously, including organic acids, volatile flavor components (VFC), monosaccharides, and amino acids. Eleven phyla and 148 genera were identified in the bacterial community, and 2 phyla and 60 genera in the fungal community. During the four stages of pickling, the dominant bacterial genera were Leuconostoc, Lactobacillus, Leuconostoc, and Lactobacillus, while the dominant fungal genera were Aspergillus, Kazachstania, Debaryomyces, and Debaryomyces, respectively. There were 32 main flavor components (5 organic acids, 19 VFCs, 3 monosaccharides, and 5 amino acids). Correlation heat mapping and bidirectional orthogonal partial least squares (O2PLS) analysis showed that the flora having close relation to flavor components included 14 genera of bacteria (Leuconostoc, Clostridium, Devosia, Lactococcus, Pectobacterium, Sphingobacterium, Serratia, Stenotrophomonas, Halanaerobium, Tetragenococcus, Chromohalobacter, Klebsiella, Acidovorax, and Acinetobacter) and 3 genera of fungi (Filobasidium, Malassezia, and Aspergillus). This study provides detailed data regarding the microbial community and flavor components during the salt-reducing pickling process of zhacai, which can be used as a reference for the development and improvement of salt-reducing pickling methods.

Anticancer activity of broccoli, its organosulfur and polyphenolic compounds

The use of natural bioactive constituents from various food sources for anticancer purposes has become increasingly popular worldwide. Broccoli (Brassica oleracea var. italica) is on the top of the consumed vegetables by the masses. Its raw matrix contains a plethora of phytochemicals, such as glucosinolates and phenolic compounds, along with rich amounts of vitamins, and minerals. Consumption of broccoli-derived phytochemicals provides strong antioxidant effects, particularly due to its sulforaphane content, while modulating numerous molecules involved in cell cycle regulation, control of apoptosis, and tuning enzyme activity. Thus, the inclusion of broccoli in the daily diet lowers the susceptibility to developing cancers. Numerous studies have underlined the undisputable role of broccoli in the diet as a chemopreventive raw food, owing to the content in sulforaphane, an isothiocyanate produced as a result of hydrolysis of precursor glucosinolates called glucoraphanin. This review will provide evidence supporting the specific role of fresh florets and sprouts of broccoli and its key bioactive constituents in the prevention and treatment of different cancers; a number of studies carried out in the in vitro and in vivo conditions as well as clinical trials were analyzed.

Glucosinolates, a natural chemical arsenal: More to tell than the myrosinase story

Glucosinolates are a group of thioglucosides that belong to the class of plant nitrogen-containing natural products. So far, very little biological activity has been associated with intact glucosinolates. The hydrolysis of glucosinolates has, for long, attracted attention because of the potent biological activity of the hydrolysis products. From allelopathic to antiparasitic, antimicrobial and antineoplastic effects, the activity spectrum of the degradation products of typical glucosinolates has been the subject of much research. The present review seeks to address the various means of glucosinolate degradation (thermal, enzymatic, or chemical degradation) and the ensuing products. It also aims to draw a comparative profile of the various antimicrobial effects of these degradation products to provide a further understanding of the biological function of these important compounds.

Understanding the role of the gut microbiome in gastrointestinal cancer: A review

Gastrointestinal cancer represents one of the most diagnosed types of cancer. Cancer is a genetic and multifactorial disease, influenced by the host and environmental factors. It has been stated that 20% of cancer is caused by microorganisms such as Helicobacter pylori, hepatitis B and C virus, and human papillomavirus. In addition to these well-known microorganisms associated with cancer, it has been shown differences in the composition of the microbiota between healthy individuals and cancer patients. Some studies have suggested the existence of the selected microorganisms and their metabolites that can promote or inhibit tumorigenesis via some mechanisms. Recent findings have shown that gut microbiome and their metabolites can act as cancer promotors or inhibitors. It has been shown that gastrointestinal cancer can be caused by a dysregulation of the expression of non-coding RNA (ncRNA) through the gut microbiome. This review will summarize the latest reports regarding the relationship among gut microbiome, ncRNAs, and gastrointestinal cancer. The potential applications of diagnosing and cancer treatments will be discussed.

Research gaps and opportunities in precision nutrition: an NIH workshop report

Precision nutrition is an emerging concept that aims to develop nutrition recommendations tailored to different people's circumstances and biological characteristics. Responses to dietary change and the resulting health outcomes from consuming different diets may vary significantly between people based on interactions between their genetic backgrounds, physiology, microbiome, underlying health status, behaviors, social influences, and environmental exposures. On 11-12 January 2021, the National Institutes of Health convened a workshop entitled "Precision Nutrition: Research Gaps and Opportunities" to bring together experts to discuss the issues involved in better understanding and addressing precision nutrition. The workshop proceeded in 3 parts: part I covered many aspects of genetics and physiology that mediate the links between nutrient intake and health conditions such as cardiovascular disease, Alzheimer disease, and cancer; part II reviewed potential contributors to interindividual variability in dietary exposures and responses such as baseline nutritional status, circadian rhythm/sleep, environmental exposures, sensory properties of food, stress, inflammation, and the social determinants of health; part III presented the need for systems approaches, with new methods and technologies that can facilitate the study and implementation of precision nutrition, and workforce development needed to create a new generation of researchers. The workshop concluded that much research will be needed before more precise nutrition recommendations can be achieved. This includes better understanding and accounting for variables such as age, sex, ethnicity, medical history, genetics, and social and environmental factors. The advent of new methods and technologies and the availability of considerably more data bring tremendous opportunity. However, the field must proceed with appropriate levels of caution and make sure the factors listed above are all considered, and systems approaches and methods are incorporated. It will be important to develop and train an expanded workforce with the goal of reducing health disparities and improving precision nutritional advice for all Americans.

Microorganisms-An Effective Tool to Intensify the Utilization of Sulforaphane

Sulforaphane (SFN) was generated by the hydrolysis of glucoraphanin under the action of myrosinase. However, due to the instability of SFN, the bioavailability of SFN was limited. Meanwhile, the gut flora obtained the ability to synthesize myrosinase and glucoraphanin, which could be converted into SFN in the intestine. However, the ability of microorganisms to synthesize myrosinase in the gut was limited. Therefore, microorganisms with myrosinase synthesis ability need to be supplemented. With the development of research, microorganisms with high levels of myrosinase synthesis could be obtained by artificial selection and gene modification. Researchers found the SFN production rate of the transformed microorganisms could be significantly improved. However, despite applying transformation technology and regulating nutrients to microorganisms, it still could not provide the best efficiency during generating SFN and could not accomplish colonization in the intestine. Due to the great effect of microencapsulation on improving the colonization ability of microorganisms, microencapsulation is currently an important way to deliver microorganisms into the gut. This article mainly analyzed the possibility of obtaining SFN-producing microorganisms through gene modification and delivering them to the gut via microencapsulation to improve the utilization rate of SFN. It could provide a theoretical basis for expanding the application scope of SFN.

Histone Deacetylase Inhibition by Gut Microbe-Generated Short-Chain Fatty Acids Entrains Intestinal Epithelial Circadian Rhythms

BACKGROUND & AIMS

The circadian clock orchestrates ∼24-hour oscillations of gastrointestinal epithelial structure and function that drive diurnal rhythms in gut microbiota. Here, we use experimental and computational approaches in intestinal organoids to reveal reciprocal effects of gut microbial metabolites on epithelial timekeeping by an epigenetic mechanism.

METHODS

We cultured enteroids in media supplemented with sterile supernatants from the altered Schaedler Flora (ASF), a defined murine microbiota. Circadian oscillations of bioluminescent PER2 and Bmal1 were measured in the presence or absence of individual ASF supernatants. Separately, we applied machine learning to ASF metabolomics to identify phase-shifting metabolites.

RESULTS

Sterile filtrates from 3 of 7 ASF species (ASF360 Lactobacillus intestinalis, ASF361 Ligilactobacillus murinus, and ASF502 Clostridium species) induced minimal alterations in circadian rhythms, whereas filtrates from 4 ASF species (ASF356 Clostridium species, ASF492 Eubacterium plexicaudatum, ASF500 Pseudoflavonifactor species, and ASF519 Parabacteroides goldsteinii) induced profound, concentration-dependent phase shifts. Random forest classification identified short-chain fatty acid (SCFA) (butyrate, propionate, acetate, and isovalerate) production as a discriminating feature of ASF "shifters." Experiments with SCFAs confirmed machine learning predictions, with a median phase shift of 6.2 hours in murine enteroids. Pharmacologic or botanical histone deacetylase (HDAC) inhibitors yielded similar findings. Further, mithramycin A, an inhibitor of HDAC inhibition, reduced SCFA-induced phase shifts by 20% (P < .05) and conditional knockout of HDAC3 in enteroids abrogated butyrate effects on Per2 expression. Key findings were reproducible in human Bmal1-luciferase enteroids, colonoids, and Per2-luciferase Caco-2 cells.

CONCLUSIONS

Gut microbe-generated SCFAs entrain intestinal epithelial circadian rhythms by an HDACi-dependent mechanism, with critical implications for understanding microbial and circadian network regulation of intestinal epithelial homeostasis.

The recent advances of glucosinolates and their metabolites: Metabolism, physiological functions and potential application strategies

Glucosinolates and their metabolites from Brassicaceae plants have received widespread attention due to their anti-inflammatory effects. Glucosinolates occurs an "enterohepatic circulation" in the body, and the glucosinolates metabolism mainly happens in the intestine. Glucosinolates can be converted into isothiocyanates by intestinal bacteria, which are active substances with remarkable anti-inflammatory, anti-cancer, anti-obesity and neuroprotective properties. This biotransformation can greatly improve the bioactivities of glucosinolates. However, multiple factors in the environment can affect the biotransformation to isothiocyanates, including acidic pH, ferrous ions and thiocyanate-forming protein. The derivatives of glucosinolates under those conditions are usually nitriles and thiocyanates, which may impair the potential health benefits. In addition, isothiocyanates are extremely unstable because of an active sulfhydryl group, which limits their applications. This review mainly summarizes the classification, synthesis, absorption, metabolism, physiological functions and potential application strategies of glucosinolates and their metabolites.

Sulfur compounds: From plants to humans and their role in chronic disease prevention

Sulfur is essential for the health of plants and is an indispensable dietary component for human health and disease prevention. Its incorporation into our food supply is heavily reliant upon the uptake of sulfur into plant tissue and our subsequent intake. Dietary requirements for sulfur are largely calculated based upon requirements for the sulfur-containing amino acids (SAA), cysteine and methionine, to meet the demands for synthesis of proteins, enzymes, co-enzymes, vitamins, and hormones. SAA are found in abundance in animal sources and are relatively low in plants. However, some plants, particularly cruciferous and allium vegetables, produce many protective sulfur-containing secondary metabolites, such as glucosinolates and cysteine sulfoxides. The variety and quantity of these sulfur-containing metabolites are extensive and their effects on human health are wide-reaching. Many benefits appear to be related to sulfur's role in redox biochemistry, protecting against uncontrolled oxidative stress and inflammation; features consistent within cardiometabolic dysfunction and many chronic metabolic diseases of aging. This narrative explores the origins and importance of sulfur, its incorporation into our food supply and dietary sources. It also explores the overarching potential of sulfur for human health, particularly around the amelioration of oxidative stress and chronic inflammation, and subsequent chronic disease prevention.

Assessment of Methodological Pipelines for the Determination of Isothiocyanates Derived from Natural Sources

Isothiocyanates are biologically active secondary metabolites liberated via enzymatic hydrolysis of their sulfur enriched precursors, glucosinolates, upon tissue plant disruption. The importance of this class of compounds lies in their capacity to induce anti-cancer, anti-microbial, anti-inflammatory, neuroprotective, and other bioactive properties. As such, their isolation from natural sources is of utmost importance. In this review article, an extensive examination of the various parameters (hydrolysis, extraction, and quantification) affecting the isolation of isothiocyanates from naturally-derived sources is presented. Overall, the effective isolation/extraction and quantification of isothiocyanate is strongly associated with their chemical and physicochemical properties, such as polarity-solubility as well as thermal and acidic stability. Furthermore, the successful activation of myrosinase appears to be a major factor affecting the conversion of glucosinolates into active isothiocyanates.

Bioavailability Study of Isothiocyanates and Other Bioactive Compounds of Brassica oleracea L. var. Italica Boiled or Steamed: Functional Food or Dietary Supplement?

The levels of bioactive compounds in broccoli and their bioavailability following broccoli intake can be affected by the cooking procedures used for vegetable preparation. In the present pilot study, we compared the human plasma bioavailability of antioxidant compounds (β-carotene, lutein and isothiocyanate) and of phylloquinone (vitamin K) on seven volunteers before and after the administration of boiled and steamed broccoli. Moreover, plasma isothiocyanate (ITCs) levels were also evaluated after the administration of a single dose of BroccoMax^®, a dietary supplement containing GLSs with active myrosinase. Steam-cooking has been demonstrated to promote higher plasma bioavailability in ITCs than boiling (AUC_STEAMED = 417.4; AUC_BOILED = 175.3) and is comparable to that reached following the intake of BroccoMax^®, a supplement containing glucoraphanin and active myrosinase (AUC = 450.1). However, the impact of boiling and steaming treatment on plasma bioavailability of lipophilic antioxidants (lutein and β-carotene) and of phylloquinone was comparable. The lutein and β-carotene plasma levels did not change after administration of steamed or boiled broccoli. Conversely, both treatments led to a similar increase of phylloquinone plasma levels. Considering the antioxidant action and the potential chemopreventive activity of ITCs, steaming treatments can be considered the most suitable cooking method to promote the health benefits of broccoli in the diet.

Dietary factors and thyroid dysfunction

Besides iodine deficiency, autoimmune Hashimoto thyroiditis is the leading cause of hypothyroidism globally, characterized by the increased titer of thyroid autoantibodies and destruction of thyroid cells. Graves' disease is the most common etiology of hyperthyroidism worldwide. Patients with thyroid dysfunction often require dietary modifications. Popular interventions include supplementation with certain vitamins and minerals, as well as trace elements such as iodine and selenium. The intake of food containing goitrogens should be limited. Goitrogens are substances of plant origin that interfere with the production of thyroid hormones, increasing the risk for goiter and hypothyroidism. The primary dietary sources of goitrogens are cruciferous vegetables, soy products, starchy plants, and some fruits. Beyond essential nutrients, there has been an increasing interest in using specific nutraceuticals, including myoinositol, Lcarnitine, melatonin, and resveratrol, as potential preventive and therapeutic agents in thyroid diseases. Even though current evidence promotes some beneficial outcomes of these nutraceuticals, further investigations are needed to clarify dose-dependent effects, duration of supplementation, combination in different clinical settings, and the exact mechanism of their action in thyroid disorders.

Anti-Cancer and Medicinal Potentials of Moringa Isothiocyanate

Moringa oleifera (M. oleifera), which belongs to the Moringaceae family, is a common herb, rich in plant compounds. It has a variety of bioactive compounds that can act as antioxidants, antibiotics, anti-inflammatory and anti-cancer agents, etc., which can be obtained in different body parts of M. oleifera. Isothiocyanates (ITCs) from M. oleifera are one class of these active substances that can inhibit cancer proliferation and promote cancer cell apoptosis through multiple signaling pathways, thus curbing cancer migration and metastasis, at the same time they have little adverse effect on normal cells. There are multiple variants of ITCs in M. oleifera, but the predominant phytochemical is 4-(α-L-rhamnosyloxy)benzyl isothiocyanate, also known as moringa isothiocyanate (MIC-1). Studies have shown that MIC-1 has the possibility to be used clinically for the treatment of diabetes, neurologic diseases, obesity, ulcerative colitis, and several cancer types. In this review, we focus on the molecular mechanisms underlying the anti-cancer and anti-chronic disease effects of MIC-1, current trends, and future direction of MIC-1 based treatment strategies. This review combines the relevant literature of the past 10 years, in order to provide more comprehensive information of MIC-1 and to fully exploit its potentiality in the clinical settings.

In-Mouth Volatile Production from Brassica Vegetables (Cauliflower) and Associations with Liking in an Adult/Child Cohort

Interactions between Brassica vegetables and human saliva can affect in-mouth odor development, which in turn may be linked to individual perception and liking. S-Methyl-l-cysteine sulfoxide is a unique substrate present in Brassicas that produces odor-active sulfur volatiles due to the activity of enzymes present in plant tissue and due to bacteria, which may be present to varying extents in an individual's oral microbiome. Proton transfer reaction mass spectrometry was applied to measure individual differences in sulfur volatile production in real time when fresh human saliva was incubated ex vivo with raw cauliflower for a cohort of child-adult pairs. Large differences in the rate of sulfur volatile production were measured between individuals, but not between age groups. Significant positive relationships were found for volatile production between the adult-child pairs, suggesting a degree of commonality in saliva composition and oral microbiome activity. Furthermore, significant negative relationships were measured between the amount of in-mouth sulfur volatile production and liking for raw cauliflower in children.

The Metabolism of Glucosinolates by Gut Microbiota

Glucosinolates (GLS) and their derivatives are secondary plant metabolites abundant in Brassicaceae. Due to the enzymatic reaction between GLS and myrosinase enzyme, characteristic compounds with a pungent taste are formed, used by plants to defend themselves against insect herbivores. These GLS derivatives have an important impact on human health, including anti-inflammation and anti-cancer effects. However, GLS derivatives' formation needs previous enzymatic reactions catalyzed by myrosinase enzyme. Many of the brassica-based foods are processed at a high temperature that inactivates enzymes, hindering its bioavailability. In the last decade, several studies showed that the human gut microbiome can provide myrosinase activity that potentially can raise the beneficial effects of consumption of vegetables rich in GLS. The variability of the human gut microbiome (HGM) in human populations and the diverse intake of GLS through the diet may lead to greater variability of the real dose of pro-healthy compounds absorbed by the human body. The exploitation of the genetic and biochemical potential of HGM and correct ecological studies of both isolated strains and mixed population are of great interest. This review focuses on the most recent advances in this field.

Metabolic and biotransformation effects on dietary glucosinolates, their bioavailability, catabolism and biological effects in different organisms

Glucosinolate-producing plants have long been recognized for both their distinctive benefits to human nutrition and their resistance traits against pathogens and herbivores. Despite the accumulation of glucosinolates (GLS) in plants is associated with their resistance to various biotic and abiotic stresses, the defensive and biological activities of GLS are commonly conveyed by their metabolic products. In view of this, metabolism is considered the driving factor upon the interactions of GLS-producing plants with other organisms, also influenced by plant and plant attacking or digesting organism characteristics. Several microbial pathogens and insects have evolved the capacity to detoxify GLS-hydrolysis products or inhibit their formation via different means, highlighting the relevance of their metabolic abilities for the plants' defense system activation and target organism detoxification. Strikingly, some bacteria, fungi and insects can likewise produce their own myrosinase (MYR)-like enzymes in one of the most important adaptation strategies against the GLS-MYR plant defense system. Knowledge of GLS metabolic pathways in herbivores and pathogens can impact plant protection efforts and may be harnessed upon for genetically modified plants that are more resistant to predators. In humans, the interest in the implementation of GLS in diets for the prevention of chronic diseases has grown substantially. However, the efficiency of such approaches is dependent on GLS bioavailability and metabolism, which largely involves the human gut microbiome. Among GLS-hydrolytic products, isothiocyanates (ITC) have shown exceptional properties as chemical plant defense agents against herbivores and pathogens, along with their health-promoting benefits in humans, at least if consumed in reasonable amounts. Deciphering GLS metabolic pathways provides critical information for catalyzing all types of GLS towards the generation of ITCs as the biologically most active metabolites. This review provides an overview on contrasting metabolic pathways in plants, bacteria, fungi, insects and humans towards GLS activation or detoxification. Further, suggestions for the preparation of GLS containing plants with improved health benefits are presented.

DNA methylome, transcriptome, and prostate cancer prevention by phenethyl isothiocyanate in TRAMP mice

Epigenetics/epigenomics has been shown to be involved in carcinogenesis. However, how the epigenome would be altered in the transgenic adenocarcinoma of the mouse prostate (TRAMP) cancer model and the effect of cancer chemopreventive phytochemical phenethyl isothiocyanate (PEITC) on the epigenome in TRAMP mice are not known. PEITC has been reported to reduce the risk of many cancers including prostate cancer (PCa). In this study, male TRAMP mice were fed a control diet or diet containing 0.05% PEITC from 8 weeks to 16 weeks. The tumor incidence was reduced in the PEITC diet (0/6) as compared with the control diet (6/7). RNA-sequencing (RNA-seq) analyses on nontumor and tumor prostatic tissues revealed several pathways like cell cycle/Cdc42 signaling, inflammation, and cancer-related signaling, were activated in prostate tissues of TRAMP mice but were reversed or attenuated in TRAMP mice fed with PEITC diet. DNA CpG methyl-seq analyses showed that global methylation patterns of prostate samples from TRAMP mice were hugely different from those of wild-type mice. Dietary PEITC partially reversed the global methylation changes during prostatic carcinogenesis. Integration of RNA-seq and DNA methyl-seq analyses identified a list of genes, including Adgrb1 and Ebf4, with an inverse regulatory relationship between their RNA expression and CpG methylation. In summary, our current study demonstrates that alteration of the global epigenome in TRAMP prostate tumor and PEITC administration suppresses PCa carcinogenesis, impacts global CpG epigenome and transcriptome, and attenuates carcinogenic pathways like cell cycle arrest and inflammation. These results may provide insights and epigenetic markers/targets for PCa prevention and treatment in human PCa patients.

Pre-Clinical Neuroprotective Evidences and Plausible Mechanisms of Sulforaphane in Alzheimer's Disease

Sulforaphane, a potent dietary bioactive agent obtainable from cruciferous vegetables, has been extensively studied for its effects in disease prevention and therapy. Sulforaphane potently induces transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated expression of detoxification, anti-oxidation, and immune system-modulating enzymes, and possibly acts as an anti-carcinogenic agent. Several clinical trials are in progress to study the effect of diverse types of cruciferous vegetables and sulforaphane on prostate cancer, breast cancer, lung cancer, atopic asthmatics, skin aging, dermatitis, obesity, etc. Recently, the protective effects of sulforaphane on brain health were also considerably studied, where the studies have further extended to several neurological diseases, including Alzheimer’s disease (AD), Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, multiple sclerosis, autism spectrum disorder, and schizophrenia. Animal and cell studies that employ sulforaphane against memory impairment and AD-related pre-clinical biomarkers on amyloid-β, tau, inflammation, oxidative stress, and neurodegeneration are summarized, and plausible neuroprotective mechanisms of sulforaphane to help prevent AD are discussed. The increase in pre-clinical evidences consistently suggests that sulforaphane has a multi-faceted neuroprotective effect on AD pathophysiology. The anti-AD-like evidence of sulforaphane seen in cells and animals indicates the need to pursue sulforaphane research for relevant biomarkers in AD pre-symptomatic populations.

Cabbage and fermented vegetables: From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT1 R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT1 R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.

Cancer Related Anemia: An Integrated Multitarget Approach and Lifestyle Interventions

Cancer is often accompanied by worsening of the patient's iron profile, and the resulting anemia could be a factor that negatively impacts antineoplastic treatment efficacy and patient survival. The first line of therapy is usually based on oral or intravenous iron supplementation; however, many patients remain anemic and do not respond. The key might lie in the pathogenesis of the anemia itself. Cancer-related anemia (CRA) is characterized by a decreased circulating serum iron concentration and transferrin saturation despite ample iron stores, pointing to a more complex problem related to iron homeostatic regulation and additional factors such as chronic inflammatory status. This review explores our current understanding of iron homeostasis in cancer, shedding light on the modulatory role of hepcidin in intestinal iron absorption, iron recycling, mobilization from liver deposits, and inducible regulators by infections and inflammation. The underlying relationship between CRA and systemic low-grade inflammation will be discussed, and an integrated multitarget approach based on nutrition and exercise to improve iron utilization by reducing low-grade inflammation, modulating the immune response, and supporting antioxidant mechanisms will also be proposed. Indeed, a Mediterranean-based diet, nutritional supplements and exercise are suggested as potential individualized strategies and as a complementary approach to conventional CRA therapy.

Glucosinolates in Brassica Vegetables: Characterization and Factors That Influence Distribution, Content, and Intake

Glucosinolates (GSLs) are a class of sulfur-containing compounds found predominantly in the genus Brassica of the Brassicaceae family. Certain edible plants in Brassica, known as Brassica vegetables, are among the most commonly consumed vegetables in the world. Over the last three decades, mounting evidence has suggested an inverse association between consumption of Brassica vegetables and the risk of various types of cancer. The biological activities of Brassica vegetables have been largely attributed to the hydrolytic products of GSLs. GSLs can be hydrolyzed by enzymes; thermal or chemical degradation also breaks down GSLs. There is considerable variation of GSLs in Brassica spp., which are caused by genetic and environmental factors. Most Brassica vegetables are consumed after cooking; common cooking methods have a complex influence on the levels of GSLs. The variationof GSLs in Brassica vegetables and the influence of cooking and processing methods ultimately affect their intake and health-promoting properties.

Allyl Isothiocyanate Protects Acetaminophen-Induced Liver Injury via NRF2 Activation by Decreasing Spontaneous Degradation in Hepatocyte

Acetaminophen (APAP) is one of the most frequently prescribed analgesic and anti-pyretic drugs. However, APAP-induced hepatotoxicity is a major cause of acute liver failure globally. While the therapeutic dose is safe, an overdose of APAP produces an excess of the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI), subsequently resulting in hepatotoxicity. Allyl isothiocyanate (AITC), a bioactive molecule in cruciferous plants, is reported to exert various biological effects, including anti-inflammatory, anti-cancer, and anti-microbial effects. Notably, AITC is known for activating nuclear factor erythroid 2-related factor 2 (NRF2), but there is limited evidence supporting the beneficial effects on hepatocytes and liver, where AITC is mainly metabolized. We applied a mouse model in the current study to investigate whether AITC protects the liver against APAP-induced injury, wherein we observed the protective effects of AITC. Furthermore, NRF2 nuclear translocation and the increase of target genes by AITC treatment were confirmed by in vitro experiments. APAP-induced cell damage was attenuated by AITC via an NRF2-dependent manner, and rapid NRF2 activation by AITC was attributed to the elevation of NRF2 stability by decreasing its spontaneous degradation. Moreover, liver tissues from our mouse experiment revealed that AITC increases the expression of heme oxygenase-1 (HO-1), an NRF2 target gene, confirming the potential of AITC as a hepatoprotective agent that induces NRF2 activation. Taken together, our results indicate the potential of AITC as a natural-product-derived NRF2 activator targeting the liver.

Safety of rapeseed powder from Brassica rapa L. and Brassica napus L. as a Novel food pursuant to Regulation (EU) 2015/2283

Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the safety of rapeseed powder from Brassica rapa L. and Brassica napus L. as a novel food (NF) pursuant to Regulation (EU) 2015/2283. Rapeseed powder will be produced from the seeds of non-genetically modified double low (00) cultivars that are varieties with a low content of erucic acid and reduced content of glucosinolates compared to older varieties. The applicant developed a production process designed to further reduce the content of glucosinolates and other undesirable compounds such as phytates. The NF will be used as a food ingredient added to a number of food products. The target population is the general population from 1 year of age. The maximum estimated intake of the NF is 18-21 g/day in adolescents, adults and elderly (corresponding to 0.35, 0.23 and 0.25 g/kg body weight (bw) per day, respectively). The levels of undesirable compounds in this NF, such as erucic acid, glucosinolates and phytates, are below levels which would raise concerns. The EFSA NDA Panel has previously assessed the safety of similar products for human consumption and there is extensive experience on the use of rapeseed in animal feed. The applicant provided a human study on the safety and tolerability of the NF and no safety concerns were identified. The Panel considers that the NF, i.e. rapeseed powder from Brassica rapa L. and Brassica napus L., is safe at the proposed conditions of use.

The glucosinolates and their bioactive derivatives in Brassica: a review on classification, biosynthesis and content in plant tissues, fate during and after processing, effect on the human organism and interaction with the gut microbiota

The present study is a systematic review of the scientific literature reporting content, composition and biosynthesis of glucosinolates (GLS), and their derivative compounds in Brassica family. An amended classification of brassica species, varieties and their GLS content, organized for the different plant organs and in uniformed concentration measure unit, is here reported for the first time in a harmonized and comparative manner. In the last years, the studies carried out on the effect of processing on vegetables and the potential benefits for human health has increased rapidly and consistently the knowledge on the topic. Therefore, there was the need for an updated revision of the scientific literature of pre- and post-harvest modifications of GLS content, along with the role of gut microbiota in influencing their bioavailability once they are ingested. After analyzing and standardizing over 100 articles and the related data, the highest GLS content in Brassica, was declared in B. nigra (L.) W. D. J. Koch (201.95 ± 53.36 µmol g^-1), followed by B. oleracea Alboglabra group (180.9 ± 70.3 µmol g^-1). The authors also conclude that food processing can influence significantly the final content of GLS, considering the most popular methods: boiling, blanching, steaming, the latter can be considered as the most favorable to preserve highest level of GLS and their deriviatives. Therefore, a mild-processing strategic approach for GLS or their derivatives in food is recommended, in order to minimize the loss of actual bioactive impact. Finally, the human gut microbiota is influenced by Brassica-rich diet and can contribute in certain conditions to the increasing of GLS bioavailability but further studies are needed to assess the actual role of microbiomes in the bioavailability of healthy glucosinolate derivatives.

Methyl Jasmonate Treatment of Broccoli Enhanced Glucosinolate Concentration, Which Was Retained after Boiling, Steaming, or Microwaving

Exogenous methyl jasmonate (MeJA) treatment was known to increase the levels of neoglucobrassicin and their bioactive hydrolysis products in broccoli (Brassica oleracea var. italica), but the fate of MeJA-induced glucosinolates (GSLs) after various cooking methods was unknown. This study measured the changes in GSLs and their hydrolysis compounds in broccoli treated with MeJA and the interaction between MeJA and cooking treatments. All cooked MeJA-treated broccoli contained significantly more GSLs than untreated broccoli (p < 0.05). After 5 min of cooking (boil, steam, microwave), MeJA-treated broccoli still contained 1.6- to 2.3-fold higher GSL content than untreated broccoli. Neoglucobrassicin hydrolysis products were also significantly greater in steamed and microwaved MeJA-treated broccoli. The results show that exogenous MeJA treatment increases neoglucobrassicin and its hydrolysis compounds in broccoli even after cooking. Once the positive and negative effects of these compounds are better understood, the results of this experiment can be a valuable tool to help food scientists, nutrition scientists, and dieticians determine how to incorporate raw or cooked broccoli and Brassica vegetables in the diet.

Altered nutrient status reprograms host inflammation and metabolic health via gut microbiota

The metabolism of macro- and micronutrients is a complex and highly regulated biological process. An imbalance in the metabolites and their signaling networks can lead to nonresolving inflammation and consequently to the development of chronic inflammatory-associated diseases. Therefore, identifying the accumulated metabolites and altered pathways during inflammatory disorders would not only serve as "real-time" markers but also help in the development of nutritional therapeutics. In this review, we explore recent research that has delved into elucidating the effects of carbohydrate/calorie restriction, protein malnutrition, lipid emulsions and micronutrient deficiencies on metabolic health and inflammation. Moreover, we describe the integrated stress response in terms of amino acid starvation and lipemia and how this modulates new age diseases such as inflammatory bowel disease and atherosclerosis. Lastly, we explain the latest research on metaflammation and inflammaging. This review focuses on multiple signaling pathways, including, but not limited to, the FGF21-β-hydroxybutryate-NLRP3 axis, the GCN2-eIF2α-ATF4 pathway, the von Hippel-Lindau/hypoxia-inducible transcription factor pathway and the TMAO-PERK-FoxO1 axis. Additionally, throughout the review, we explain how the gut microbiota responds to altered nutrient status and also how antimicrobial peptides generated from nutrient-based signaling pathways can modulate the gut microbiota. Collectively, it must be emphasized that metabolic starvation and inflammation are strongly regulated by both environmental (i.e., nutrition, gut microbiome) and nonenvironmental (i.e., genetics) factors, which can influence the susceptibility to inflammatory disorders.

The influence of wasabi on the gut microbiota of high-carbohydrate, high-fat diet-induced hypertensive Wistar rats

The human gut microbiota plays a critical role in the regulation of adiposity, obesity and metabolic and cardiovascular disease. Wasabi is a pungent spice and its active component, allyl isothiocyanate, improves plasma triacylglycerol, cholesterol and high blood pressure in rodents, but it is unclear if this occurs through alterations to the composition of the microbiota. The aim of this study was to determine the effectiveness of Wasabi japonica stem and rhizome blend on ameliorating cardiovascular disease parameters including plasma sodium concentration, systolic blood pressure (SBP), plasma endothelin-1 and angiotensin II concentrations by altering the gut microbiota in a Wistar rat model of obesity and metabolic syndrome. Rats were randomized to receive a corn starch or high-carbohydrate/high-fat diet for 8 weeks before being allocated to supplementation with wasabi powder (5% (w/w) in food) or not for an additional 8 weeks. At the end of the trial, rats were grouped according to blood pressure status. Wasabi supplementation prevented the development of hypertension and was also associated with significantly increased abundance of Allobaculum, Sutterella, Uncl. S247, Uncl. Coriobacteriaceae and Bifidobacterium. Hypertension was positively correlated with higher abundance of Oscillospira, Uncl. Lachnospiraceae and Uncl. Clostridiales, Uncl. Bacteroidales and Butyricimonas. Oscillospira and Butyricimonas abundances were specifically positively correlated with systolic blood pressure. Overall, the improved host cardiovascular health in diet-induced obese rats supplemented with wasabi powder may involve changes to the gut microbiota composition.

Aryl hydrocarbon Receptor activation during in vitro and in vivo digestion of raw and cooked broccoli (brassica oleracea var. Italica)

Broccoli is rich in glucosinolates, which can be converted upon chewing and processing into Aryl hydrocarbon Receptor (AhR) ligands. Activation of AhR plays an important role in overall gut homeostasis but the role of broccoli processing on the generation of AhR ligands is still largely unknown. In this study, the effects of temperature, cooking method (steaming versus boiling), gastric pH and further digestion of broccoli on AhR activation were investigated in vitro and in ileostomy subjects. For the in vitro study, raw, steamed (t = 3 min and t = 6 min) and boiled (t = 3 min and t = 6 min) broccoli were digested in vitro with different gastric pH. In the in vivo ileostomy study, 8 subjects received a broccoli soup or a broccoli soup plus an exogenous myrosinase source. AhR activation was measured in both in vitro and in vivo samples by using HepG2-Lucia™ AhR reporter cells. Cooking broccoli reduced the AhR activation measured after gastric digestion in vitro, but no effect of gastric pH was found. Indole AhR ligands were not detected or detected at very low levels both after intestinal in vitro digestion and in the ileostomy patient samples, which resulted in no AhR activation. This suggests that the evaluation of the relevance of glucosinolates for AhR modulation in the gut cannot prescind from the way broccoli is processed, and that broccoli consumption does not necessarily produce substantial amounts of AhR ligands in the large intestine.

Targets and mechanisms of sulforaphane derivatives obtained from cruciferous plants with special focus on breast cancer - contradictory effects and future perspectives

Breast cancer is the most common type of cancer among women. Therefore, discovery of new and effective drugs with fewer side effects is necessary to treat it. Sulforaphane (SFN) is an organosulfur compound obtained from cruciferous plants, such as broccoli and mustard, and it has the potential to treat breast cancer. Hence, it is vital to find out how SFN targets certain genes and cellular pathways in treating breast cancer. In this review, molecular targets and cellular pathways of SFN are described. Studies have shown SFN inhibits cell proliferation, causes apoptosis, stops cell cycle and has anti-oxidant activities. Increasing reactive oxygen species (ROS) produces oxidative stress, activates inflammatory transcription factors, and these result in inflammation leading to cancer. Increasing anti-oxidant potential of cells and discovering new targets to reduce ROS creation reduces oxidative stress and it eventually reduces cancer risks. In short, SFN effectively affects histone deacetylases involved in chromatin remodeling, gene expression, and Nrf2 anti-oxidant signaling. This review points to the potential of SFN to treat breast cancer as well as the importance of other new cruciferous compounds, derived from and isolated from mustard, to target Keap1 and Akt, two key regulators of cellular homeostasis.

Methyl jasmonate treated broccoli: Impact on the production of glucosinolates and consumer preferences

Applying methyl jasmonate can mimic the defense response to insect damage in broccoli and enhances the production of glucosinolates, especially inducible indolyl GS-neoglucobrassicin. Previous studies have suggested that glucosinolates and their hydrolysis products are anti-carcinogenic. Therefore, MeJA treatment may increase the nutritional quality of broccoli. However, there are few reports on the sensory evaluation and consumer acceptance of MeJA-treated broccoli. In this study, an untrained consumer panel could not detect any taste differences between steamed MeJA-treated and untreated broccoli, even though the steamed MeJA-treated broccoli contained 50% more glucosinolates than untreated broccoli. The partial least square-regression model suggested that neoglucobrassicin-derived hydrolysis compounds were the major metabolites that determined overall preference for raw MeJA-treated broccoli potentially due to their potential negative sensory qualities. The results imply that MeJA treatment can increase the nutritional quality of broccoli without sacrificing taste in precooked meals or frozen vegetables.

The Effects of Vegetarian and Vegan Diets on Gut Microbiota

The difference in gut microbiota composition between individuals following vegan or vegetarian diets and those following omnivorous diets is well documented. A plant-based diet appears to be beneficial for human health by promoting the development of more diverse and stable microbial systems. Additionally, vegans and vegetarians have significantly higher counts of certain Bacteroidetes-related operational taxonomic units compared to omnivores. Fibers (that is, non-digestible carbohydrates, found exclusively in plants) most consistently increase lactic acid bacteria, such as Ruminococcus, E. rectale, and Roseburia, and reduce Clostridium and Enterococcus species. Polyphenols, also abundant in plant foods, increase Bifidobacterium and Lactobacillus, which provide anti-pathogenic and anti-inflammatory effects and cardiovascular protection. High fiber intake also encourages the growth of species that ferment fiber into metabolites as short-chain fatty acids (SCFAs), including acetate, propionate, and butyrate. The positive health effects of SCFAs are myriad, including improved immunity against pathogens, blood-brain barrier integrity, provision of energy substrates, and regulation of critical functions of the intestine. In conclusion, the available literature suggests that a vegetarian/vegan diet is effective in promoting a diverse ecosystem of beneficial bacteria to support both human gut microbiome and overall health. This review will focus on effects of different diets and nutrient contents, particularly plant-based diets, on the gut microbiota composition and production of microbial metabolites affecting the host health.

Aerial parts of maca (Lepidium meyenii Walp.) as functional vegetables with gastrointestinal prokinetic efficacy in vivo

Lepidium meyenii Walp. (maca) has been utilized in the Andean region because of its edibleness and medicinal value. The aerial parts of maca (APM) were analyzed for protein, total sugar, vitamins, amino acids, and minerals and its characteristic active ingredients at five different growth stages. The results showed the high protein, total sugar, vitamin C, niacin, potassium, and calcium contents of APM. All 17 amino acids and the characteristic active ingredients, namely, macamide, glucosinolates, adenosine, and total saponins, were detected. We examined the effects of maca plant powders on gastric emptying and intestinal propulsion and the levels of serum motilin and gastrin in atropine-treated mice. Benzyl isothiocyanate (BITC) was investigated to identify the potential active material in APM. The results revealed that both maca plant powders and BITC can promote the gastrointestinal prokinetic efficacy. Thus, APM feature potential as new functional vegetable sources.

Impact of dietary gut microbial metabolites on the epigenome

Within the past decade, epigenetic mechanisms and their modulation by natural products have gained increasing interest. Dietary bioactive compounds from various sources, including green tea, soya, fruit and berries, cruciferous vegetables, whole grain foods, fish and others, have been shown to target enzymes involved in epigenetic gene regulation, including DNA methyltransferases, histone acetyltransferases, deacetylases and demethylases in vitro and in cell culture. Also, many dietary agents were shown to alter miRNA expression. In vivo studies in animal models and humans are still limited. Recent research has indicated that the gut microbiota and gut microbial metabolites might be important mediators of diet-epigenome interactions. Inter-individual differences in the gut microbiome might affect release, metabolism and bioavailability of dietary agents and explain variability in response to intervention in human studies. Only a few microbial metabolites, including folate, phenolic acids, S-(-)equol, urolithins, isothiocyanates, and short- and long-chain fatty acids have been tested with respect to their potential to influence epigenetic mechanisms. Considering that a complex mixture of intermediary and microbial metabolites is present in human circulation, a more systematic interdisciplinary investigation of nutri-epigenetic activities and their impact on human health is called for.This article is part of a discussion meeting issue 'Frontiers in epigenetic chemical biology'.