In Brassica plants, glucosinolates are a diverse class of natural products, of which aliphatic methionine-derived glucosinolates are the most abundant form. Their structural diversity comes from the elongation of some side-chains by up to 9 carbons, which, after the formation of the core glucosinolate structure, can undergo further chemical modifications. Methylthioalkylmalate synthase (MAMS) catalyzes the iterative elongation process for aliphatic methionine-derived glucosinolates. Most biochemical studies on MAMS have been performed using liquid chromatography/mass spectrometry (LC/MS)-based assays or high-performance liquid chromatography (HPLC)-based assays. The LC/MS- and HPLC-based methods are endpoint assays, which cannot be monitored in real time and require a laborious process for data collection. These analytical methods are inefficient for performing multiple enzymatic assays needed to determine steady-state kinetic parameters or for mechanistic evaluation of pH-dependence and kinetic isotope effect studies. Although the function of MAMS has long been defined, there is a gap in knowledge as it pertains to biochemical characterization of this plant enzyme. Part of this may be due to the lack of efficient methods that can be used for this type of research. This chapter describes a continuous photometric assay to track MAMS activity in real time using the 4-aldrithiol reagent for reaction detection.

In this study, Chinese cabbage (Brassica rapa L. ssp. pekinensis) roots were solvent fractioned, and their antioxidant and anti-inflammatory effects were investigated. The antioxidant capacity (DPPH and ABTS radicals, oxygen radical absorbance capacity, and cupric reducing antioxidant capacity) was the highest in the ethyl acetate fraction (CREE) at 26.74, 69.81, 253.23, and 54.77 mg TEAC/g, respectively. The inflammatory responses were evaluated in RAW 264.7 cells stimulated with lipopolysaccharide (1 µg/mL). CREE decreased nitric oxide and prostaglandin E2 by 53.37% and 16.30%, respectively. Pro-inflammatory cytokines such as tumor necrosis factor-α, interleukin-1β, and interleukin-6 were inhibited by 36.85%, 62.99%, and 54.78%, respectively. Furthermore, inducible nitric oxide synthase, cyclooxygenase-2, and interleukin-6 genes were inhibited by 43.38%, 24.23%, and 80.85%, respectively. The results suggest that CREE is responsible for its antioxidant and anti-inflammatory effects.

Butterflies, like many insects, use gustatory and olfactory cues innately to assess the suitability of an oviposition site and are able to associate colours and leaf shapes with an oviposition reward. Studies on other insects have demonstrated that the quality of the reward is a crucial factor in forming associative memory. We set out to investigate whether the large cabbage white Pieris brassicae (Linnaeus) has the ability to associate an oviposition experience with a neutral olfactory cue. In addition, we tested whether the strength of this association is dependent on the gustatory response to the glucosinolate sinigrin, which is a known oviposition stimulus for P. brassicae. Female butterflies were able to associate a neutral odour with an oviposition experience after a single oviposition experience, both in a greenhouse and in a semi-natural outdoor setting. Moreover, butterflies performed best when trained with concentrations of sinigrin that showed the strongest response by specific gustatory neurons on the forelegs. Our study provides novel insight into the role of both gustatory and olfactory cues during oviposition learning in lepidopterans and contributes to a better understanding of how these insects might be able to adapt to a rapidly changing environment.

Nicotinamide adenine dinucleotide (NAD+) is a redox cofactor and signal central to cell metabolisms. Disrupting NAD homeostasis in plant alters growth and stress resistance, yet the underlying mechanisms remain largely unknown. Here, by combining genetics with multi-omics, we discover that NAD+ deficiency in qs-2 caused by mutation in NAD+ biosynthesis gene-Quinolinate Synthase retards growth but induces biosynthesis of defense compounds, notably aliphatic glucosinolates that confer insect resistance. The elevated defense in qs-2 is resulted from activated jasmonate biosynthesis, critically hydroperoxidation of α-linolenic acid by the 13-lipoxygenase (namely LOX2), which is escalated via the burst of chloroplastic ROS-singlet oxygen (1O2). The NAD+ deficiency-mediated JA induction and defense priming sequence in plants is recapitulated upon insect infestation, suggesting such defense mechanism operates in plant stress response. Hence, NAD homeostasis is a pivotal metabolic checkpoint that may be manipulated to navigate plant growth and defense metabolism for stress acclimation.

Fungal infections are becoming a severe threat to the security of global public health due to the extensive use of antibiotic medications and the rise in immune-deficient patients globally. Additionally, there is an increase in the development of fungus resistance to available antifungal medications. It is necessary to focus on the development of new antifungal medications in order to address these problems. The wide range of chemical structures, low cost, high availability, high antimicrobial action, and lack of adverse effects are the characteristics of plant secondary metabolites. In order to find and develop new antifungal medications, plant secondary metabolites like glucosinolate (GSL) derivatives are crucial sources of information. These natural compounds are enzymatically transformed into isothiocyanates (ITCs), nitriles, epithionitriles, oxazolidin-2-thion, and thiocyanate when they get mechanically damaged. The current review offers a thorough understanding of how isothiocyanates affect fungi with detailed mechanism. Along with this antifungal activity of nitriles, epithionitriles, oxazolidin-2-thion, and thiocyanate are mentioned. The review summarizes our present understanding of the following subjects: role of isothiocyanate by inhibiting aflatoxin biosynthesis, effect of isothiocyanate on transcriptomes, isothiocyanate targets cell membrane, role of isothiocyanate in efflux, and the role of isothiocyanate in synergistic activity. Antifungal activity of nitrile, epithionitrile, oxazolidine-2-thion, and thiocyanate is mentioned. Cytotoxicity study and clinical trials data were also added. More extensive studies will be needed in this field to assess safety concerns and clinical efficacies of GSL derivatives.

Secondary metabolites play an essential role in plant defense. However, the role of glucosinolates and phenols in brassica crop yield in the context of environmentally friendly agricultural practices has not been established. Our study investigated the effects of a Brassica extract, rich in these metabolites, on the physiology and metabolism of broccoli (Brassica oleracea L. var. italica) seedlings and the subsequent development of the plants in adult stages. The results showed an increase in growth in the extract-treated seedlings, which was associated with an alteration of primary and secondary metabolism. In particular, there was an increase in the levels of amino acids, phenolic compounds and hormones, while the levels of glucosinolates decreased. Lipid peroxidation diminished in treated plants, indicating improved membrane integrity. Treated plants subsequently grown in hydroponically showed increased water use efficiency, transpiration, and internal carbon, which contributed to the improved growth of these plants. Overall, our findings underscore the potential of the glucosinolates and phenols ratio as essential to improve crop growth and stress tolerance, as well as revealed the interest of studying the mechanisms involved in the possible uptake and integration of GSLs by broccoli seedlings after external application.

The present study investigates the interactions between eight glucosinolate hydrolysis products (GHPs) sourced from broccoli by-products and the detoxifying enzymes of Botrytis cinerea, namely eburicol 14-alpha-demethylase (CYP51) and glutathione-S-transferase (GST), through in silico analysis. Additionally, in vitro assays were conducted to explore the impact of these compounds on fungal growth. Our findings reveal that GHPs exhibit greater efficacy in inhibiting conidia germination compared to mycelium growth. Furthermore, the results demonstrate the antifungal activity of glucosinolate hydrolysis products derived from various parts of the broccoli plant, including inflorescences, leaves, and stems, against B. cinerea. Importantly, the results suggest that these hydrolysis products interact with the detoxifying enzymes of the fungus, potentially contributing to their antifungal properties. Extracts rich in GHPs, particularly iberin and indole-GHPs, derived from broccoli by-products emerge as promising candidates for biofungicidal applications, offering a sustainable and novel approach to plant protection by harnessing bioactive compounds from agricultural residues.

Brassica oleracea and Allium vegetables are known for their unique, family specific, water-soluble phytochemicals, glucosinolates, and S-alk(en)yl-l-cysteine sulfoxides, respectively. However, they are also important delivery systems of several other health-related compounds, such as carotenoids (lipid-soluble phytochemicals), vitamin C (water-soluble micronutrient), and vitamin K1 (lipid-soluble micronutrient). When all-year-round availability or transport over long distances is targeted for these often seasonal, locally grown vegetables, processing becomes indispensable. However, the vegetable processing chain, which consists of multiple steps (e.g., pretreatment, preservation, storage, preparation), can impact the nutritional quality of these vegetables corresponding to the nature of the health-related compounds and their susceptibility to (bio)chemical conversions. Since information about the impact of the vegetable processing chain is scattered per compound or processing step, this review targets an integration of the state of the art and discusses needs for future research. Starting with a discussion on substrate-enzyme location within the vegetable matrix, an overview is provided of the impact and potential of processing, encompassing a wide range of (nonenzymatic) conversions.

The Brassicaceae family, commonly referred to as cruciferous plants, is globally cultivated and consumed, with the Brassica genus being particularly renowned for its functional components. These vegetables are rich sources of nutrients and health-promoting phytochemicals, garnering increased attention in recent years. This study presents a comprehensive microscopic, chromatographic, and spectroscopic characterization of Brassica napus L. seeds from Kazakhstan aimed at elucidating their morphological features and chemical composition. Microscopic analysis revealed distinct localization of flavonoids, total lipids, and alkaloids. High-performance thin-layer chromatography (HPTLC) analysis of seed extracts demonstrated a complex chemical profile with significant quantities of non-polar compounds in the hexane extracts. Additionally, methanolic extracts revealed the presence of diverse chemical compounds, including alkaloids, flavonoids, and glucosinolates. The chemical composition exhibited varietal differences across different Brassica species, with B. napus L. seeds showing higher concentrations of bioactive compounds. Furthermore, liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-QToF-MS) analysis provided insights into the chemical composition, with sinapine isomers, feruloyl, and sinapoyl choline derivatives as major compounds in the seeds. This study contributes to a better understanding of the chemical diversity and quality control methods\' approximations of B. napus L. seeds, highlighting their importance in functional food and nutraceutical applications.

Glucosinolates (GSLs) are plant secondary metabolites commonly found in the cruciferous vegetables of the Brassicaceae family, offering health benefits to humans and defense against pathogens and pests to plants. In this study, we investigated 23 GSL compounds\' relative abundance in four tissues of five different Brassica oleracea morphotypes. Using the five corresponding high-quality B. oleracea genome assemblies, we identified 183 GSL-related genes and analyzed their expression with mRNA-Seq data. GSL abundance and composition varied strongly, among both tissues and morphotypes, accompanied by different gene expression patterns. Interestingly, broccoli exhibited a nonfunctional AOP2 gene due to a conserved 2OG-FeII_Oxy domain loss, explaining the unique accumulation of two health-promoting GSLs. Additionally, transposable element (TE) insertions were found to affect the gene structure of MAM3 genes. Our findings deepen the understanding of GSL variation and genetic regulation in B. oleracea morphotypes, providing valuable insights for breeding with tailored GSL profiles in these crops.