Phytoalexins of the crucifer Barbarea vulgaris: Structural profile and correlation with glucosinolate turnover.

Phytoalexins are antimicrobial plant metabolites elicited by microbial attack or abiotic stress. We investigated phytoalexin profiles after foliar abiotic elicitation in the crucifer Barbarea vulgaris and interactions with the glucosinolate-myrosinase system. The treatment for abiotic elicitation was a foliar spray with CuCl2 solution, a usual eliciting agent, and three independent experiments were carried out. Two genotypes of B. vulgaris (G-type and P-type) accumulated the same three major phytoalexins in rosette leaves after treatment: phenyl-containing nasturlexin D and indole-containing cyclonasturlexin and cyclobrassinin. Phytoalexin levels were investigated daily by UHPLC-QToF MS and tended to differ among plant types and individual phytoalexins. In roots, phytoalexins were low or not detected. In treated leaves, typical total phytoalexin levels were in the range 1-10 nmol/g fresh wt. during three days after treatment while typical total glucosinolate (GSL) levels were three orders of magnitude higher. Levels of some minor GSLs responded to the treatment: phenethylGSL (PE) and 4-substituted indole GSLs. Levels of PE, a suggested nasturlexin D precursor, were lower in treated plants than controls. Another suggested precursor GSL, 3-hydroxyPE, was not detected, suggesting PE hydrolysis to be a key biosynthetic step. Levels of 4-substituted indole GSLs differed markedly between treated and control plants in most experiments, but not in a consistent way. The dominant GSLs, glucobarbarins, are not believed to be phytoalexin precursors. We observed statistically significant linear correlations between total major phytoalexins and the glucobarbarin products barbarin and resedine, suggesting that GSL turnover for phytoalexin biosynthesis was unspecific. In contrast, we did not find correlations between total major phytoalexins and raphanusamic acid or total glucobarbarins and barbarin. In conclusion, two groups of phytoalexins were detected in B. vulgaris, apparently derived from the GSLs PE and indol-3-ylmethylGSL. Phytoalexin biosynthesis was accompanied by depletion of the precursor PE and by turnover of major non-precursor GSLs to resedine. This work paves the way for identifying and characterizing genes and enzymes in the biosyntheses of phytoalexins and resedine.

Removal of anti-nutritional factors of rapeseed protein isolate (RPI) and toxicity assessment of RPI.

We prepared a detoxified rapeseed protein isolate (RPI) by phytase/ethanol treatment based on alkaline extraction and acidic precipitation. Contents of protein, fat, ash, moisture, crude fiber, glucosinolates, phytic acid, and phenolics and color were determined. To evaluate the safety of detoxified RPI, five groups of C57 mice (detoxified RPI [10 and 20 g kg-1]; commercial soybean protein isolate (SPI) [10 g kg-1]; non-detoxified RPI [10 g kg-1]; control) were used in the acute-toxicity test. Bodyweight and pathology parameters were recorded at different time points, followed by macroscopic examination, organ-weight measurement and microstructure examination. After pretreatment of rapeseed meals with phytase (enzyme : substrate ratio, 1 : 5 mg g-1) for 1.5 h and two-time ethanol extraction for precipitated protein, the chemical characteristics in RPI were protein (88.26%), fat (0.57%), ash (2.72%), moisture (1.90%), crude fiber (0.77%), glucosinolates (0 µmol g-1), phytic acid (0.17%), phenolics (0.36%) and whiteness (73.38). Treatment resulted in significant removal of anti-nutritional factors (ANFs) and increased whiteness in detoxified RPI compared with non-detoxified RPI, and lower than in cruciferin-rich canola protein isolate (Puratein®). Experimental-related effects on bodyweight, clinical observations, or clinicopathology, in mice treated with detoxified RPI were not observed except for a decreased thyroid gland/parathyroid gland index in mice treated with non-detoxified RPI. Furthermore, the no-observed-effect level (NOEL) was 10 g kg-1 of detoxified RPI, whereas the no-observed-adverse-effect-level (NOAEL) was the highest fed level of 20 g kg-1 of detoxified RPI. Overall, detoxified RPI prepared by the combined treatment of phytase and ethanol was considered safe under the conditions tested, in which the contents of the main ANFs were reduced significantly.

Lepidium sativum Sprouts Grown under Elevated CO2 Hyperaccumulate Glucosinolates and Antioxidants and Exhibit Enhanced Biological and Reduced Antinutritional Properties.

The nutritional and health-promoting properties of plants are largely determined by their tissue chemistry. Tuning growth conditions could affect the accumulation of phytochemicals and, therefore, enhance the biological activities. Herein, the impact of elevated CO2 (eCO2; 620 µmol CO2 mol-1 air) on growth and chemical composition of sprouts of three Lepidium sativum cultivars (Haraz, Khider and Rajab) was investigated. Changes in the sprout actions against some human chronic diseases were evaluated. eCO2 induced biomass accumulation (1.46-, 1.47- and 2-fold in Haraz, Khider and Rajab, respectively) and pigment accumulation and reduced the level of antinutrients in L. sativum cultivars. Compared to the control, eCO2 induced total glucosinolate accumulation (0.40-, 0.90- and 1.29-fold in Khider, Haraz and Rajab, respectively), possibly through increased amino acid production, and their hydrolysis by myrosinase. In line with increased polyphenol production, improved phenylalanine ammonia lyase activity was observed. The antioxidant, anti-inflammatory, hypocholesterolemic, antibacterial and anticancer activities of the produced sprouts were significantly improved by sprouting and eCO2 exposure. PCA indicated that the cultivars showed interspecific responses. Thus, the present study confirms the synergistic effect of sprouting with eCO2 exposure as a promising approach to produce more bioactive L. sativum sprouts.

Metabolic analysis of unripe papaya (Carica papaya L.) to promote its utilization as a functional food.

Papaya (Carica papaya L.) is widely cultivated in tropical and subtropical countries. While ripe fruit is a popular food item globally, the unripe fruit is only consumed in some Asian countries. To promote the utilization of unripe papaya based on the compositional changes of biological active metabolites, we performed liquid chromatography-Orbitrap-mass spectrometry-based analysis to reveal the comprehensive metabolite profile of the peel and pulp of unripe and ripe papaya fruits. The number of peaks annotated as phenolics and aminocarboxylic acids increased in the pulp and peel of ripe fruit, respectively. Putative carpaine derivatives, known alkaloids with cardiovascular effects, decreased, while carpamic acid derivatives increased in the peel of ripe fruit. Furthermore, the functionality of unripe fruit, the benzyl glucosinolate content, total polyphenol content, and proteolytic activity were detectable after heating and powder processing treatments, suggesting a potential utilization in powdered form as functional material.

Chemical profiling and separation of bioactive secondary metabolites in Maca (Lepidium peruvianum) by normal and reverse phase thin layer chromatography coupled to desorption electrospray ionization-mass spectrometry.

Maca is a Peruvian tuberous root of the Brassicaceae family grown in the central Andes between altitudes of 4000 and 4500 m. The medicinal plant is a nutraceutical with important biological activities and health effects. In this study, we report a rapid high-performance thin layer chromatography (HPTLC)-(-)desorption electrospray ionization (DESI)-mass spectrometry (MS) method to profile and separate intact glucosinolates without prior biochemical modifications from the hydromethanolic extracts of two phenotypes, red and black Maca (Lepidium peruvianum) seeds. In the first stage of the plant's life cycle, aromatic glucosinolates were the main chemical constituents whereby six aromatic, three indole, and one aliphatic glucosinolate were tentatively identified. At the seedling stage, glucolepigramin/Glucosinalbin was the most predominant precursor, rather than Glucotropaeolin, which is mainly found in hypocotyls and roots. These findings lead us to suggest that glucolepigramin/glucosinalbin play a major role as active precursors in the biosynthetic pathways of other secondary metabolites in the early stages of plant development. Between red and black Maca seeds, only minor differences in the relative abundances of glucosinolates were observed rather than different plant metabolites. For the first time, we report six potential plant antibiotics, phytoanticipins: glycosylated ascorbigens and dihydroascorbigens from Maca seeds. We also investigated a targeted reverse phase C18 functionalized TLC-DESI-MS method with high sensitivity and specificity for Brassicaceae fatty acids in Maca seeds and health supplements such as black Maca root lyophilized powder and tinctures. The investigation of secondary metabolites by normal and reverse phase TLC-DESI-MS methods, described in this study, can aid in their identification as they begin to emerge in later stages of development in plant tissues such as leaves, hypocotyls, and roots.

Glucosinolates of Lepidium graminifolium L. (Brassicaceae) from Croatia.

The glucosinolate (GSL) profiles (inflorescence, stem, root, and fruit) of the wild-growing plant Lepidium graminifolium L. (Brassicaceae) from Croatia was established by LC-MS analysis. During this investigation, we confirmed the presence of benzyl- (1), 3-methoxybenzyl- (2), 4-hydroxybenzyl- (4), 4-methoxyindol-3-ylmethyl- (7) GSLs and reported for the first time in the plant the presence of (2 R)-hydroxybut-3-enyl- (11), (2S)-hydroxybut-3-enyl- (12), but-3-enyl- (13), and 2-phenylethyl- (14) GSLs. Finally, 3-hydroxybenzyl GSL (3) was isolated for the first time from L. graminifolium inflorescence and characterised by spectroscopic data interpretation.

Glucosinolates: Natural Occurrence, Biosynthesis, Accessibility, Isolation, Structures, and Biological Activities.

Glucosinolates (GSLs) are secondary plant metabolites abundantly found in plant order Brassicales. GSLs are constituted by an S-ß-d-glucopyrano unit anomerically connected to O-sulfated (Z)-thiohydroximate moiety. The side-chain of the O-sulfate thiohydroximate moiety, which is derived from a different amino acid, contributes to the diversity of natural GSL, with more than 130 structures identified and validated to this day. Both the structural diversity of GSL and their biological implication in plants have been biochemically studied. Although chemical syntheses of GSL have been devised to give access to these secondary metabolites, direct extraction from biomass remains the conventional method to isolate natural GSL. While intact GSLs are biologically inactive, various products, including isothiocyanates, nitriles, epithionitriles, and cyanides obtained through their hydrolysis of GSLs, exhibit many different biological activities, among which several therapeutic benefits have been suggested. This article reviews natural occurrence, accessibility via chemical, synthetic biochemical pathways of GSL, and the current methodology of extraction, purification, and characterization. Structural information, including the most recent classification of GSL, and their stability and storage conditions will also be discussed. The biological perspective will also be explored to demonstrate the importance of these prominent metabolites.

Human, Animal and Plant Health Benefits of Glucosinolates and Strategies for Enhanced Bioactivity: A Systematic Review.

Glucosinolates (GSs) are common anionic plant secondary metabolites in the order Brassicales. Together with glucosinolate hydrolysis products (GSHPs), they have recently gained much attention due to their biological activities and mechanisms of action. We review herein the health benefits of GSs/GSHPs, approaches to improve the plant contents, their bioavailability and bioactivity. In this review, only literature published between 2010 and March 2020 was retrieved from various scientific databases. Findings indicate that these compounds (natural, pure, synthetic, and derivatives) play an important role in human/animal health (disease therapy and prevention), plant health (defense chemicals, biofumigants/biocides), and food industries (preservatives). Overall, much interest is focused on in vitro studies as anti-cancer and antimicrobial agents. GS/GSHP levels improvement in plants utilizes mostly biotic/abiotic stresses and short periods of phytohormone application. Their availability and bioactivity are directly proportional to their contents at the source, which is affected by methods of food preparation, processing, and extraction. This review concludes that, to a greater extent, there is a need to explore and improve GS-rich sources, which should be emphasized to obtain natural bioactive compounds/active ingredients that can be included among synthetic and commercial products for use in maintaining and promoting health. Furthermore, the development of advanced research on compounds pharmacokinetics, their molecular mode of action, genetics based on biosynthesis, their uses in promoting the health of living organisms is highlighted.

Preparation of Poly(glycidyl methacrylate) (PGMA) and Amine Modified PGMA Adsorbents for Purification of Glucosinolates from Cruciferous Plants.

Glucosinolates (GLs) are of great interest for their potential as antioxidant and anticancer compounds. In this study, macroporous crosslinked copolymer adsorbents of poly (glycidyl methacrylate) (PGMA) and its amine (ethylenediamine, diethylamine, triethylamine)-modified derivatives were prepared and used to purify the GLS glucoerucin in a crude extract obtained from a cruciferous plant. These four adsorbents were evaluated by comparing their adsorption/desorption and decolorization performance for the purification of glucoerucin from crude plant extracts. According to the results, the strongly basic triethylamine modified PGMA (PGMA-III) adsorbent showed the best adsorption and desorption capacity of glucoerucin, and its adsorption data was a good fit to the Freundlich isotherm model and pseudo-second-order kinetics; the PGMA adsorbent gave the optimum decolorization performance. Furthermore, dynamic adsorption/desorption experiments were carried out to optimize the purification process. Two glass columns were serially connected and respectively wet-packed with PGMA and PGMA-III adsorbents so that glucoerucin could be decolorized and isolated from crude extracts in one process. Compared with KCl solution, aqueous ammonia was a preferable desorption solvent for the purification of glucoerucin and overcame the challenges of desalination efficiency, residual methanol and high operation costs. The results showed that after desorption with 10% aqueous ammonia, the purity of isolated glucoerucin was 74.39% with a recovery of 80.63%; after decolorization with PGMA adsorbent, the appearance of glucoerucin was improved and the purity increased by 11.30%. The process of using serially connected glass columns, wet-packed with PGMA and PGMA-III, may provide a simple, low-cost, and efficient method for the purification of GLs from cruciferous plants.

Biological Effects of Glucosinolate Degradation Products from Horseradish: A Horse that Wins the Race.

Horseradish degradation products, mainly isothiocyanates (ITC) and nitriles, along with their precursors glucosinolates, were characterized by GC-MS and UHPLC-MS/MS, respectively. Volatiles from horseradish leaves and roots were isolated using microwave assisted-distillation (MAD), microwave hydrodiffusion and gravity (MHG) and hydrodistillation (HD). Allyl ITC was predominant in the leaves regardless of the isolation method while MAD, MHG, and HD of the roots resulted in different yields of allyl ITC, 2-phenylethyl ITC, and their nitriles. The antimicrobial potential of roots volatiles and their main compounds was assessed against sixteen emerging food spoilage and opportunistic pathogens. The MHG isolate was the most active, inhibiting bacteria at minimal inhibitory concentrations (MICs) from only 3.75 to 30 µg/mL, and fungi at MIC50 between <0.12 and 0.47 µg/mL. Cytotoxic activity of volatile isolates and their main compounds were tested against two human cancer cell lines using MTT assay after 72 h. The roots volatiles showed best cytotoxic activity (HD; IC50 = 2.62 µg/mL) against human lung A549 and human bladder T24 cancer cell lines (HD; IC50 = 0.57 µg/mL). Generally, 2-phenylethyl ITC, which was tested for its antimicrobial and cytotoxic activities along with two other major components allyl ITC and 3-phenylpropanenitrile, showed the best biological activities.

Microwave-Assisted versus Conventional Isolation of Glucosinolate Degradation Products from Lunaria annua L. and Their Cytotoxic Activity.

Glucosinolates (GSLs) from Lunaria annua L. seeds were analyzed qualitatively and quantitatively by their desulfo counterparts using UHPLC-DAD-MS/MS technique and by their volatile breakdown products, isothiocyanates (ITCs), using GC-MS technique. GSL breakdown products were obtained by conventional techniques (hydrodistillation in a Clevenger type apparatus (HD), CH2Cl2 extraction after myrosinase hydrolysis (EXT) for 24 h) as well as by modern techniques, microwave-assisted distillation (MAD) and microwave hydrodiffusion and gravity (MHG). Seven GSLs were identified as follows: isopropyl GSL (1), sec-butyl GSL (2), 5-(methylsulfinyl)pentyl GSL (3), 6-(methylsulfinyl)hexyl GSL (4), 5-(methylsulfanyl)pentyl GSL (5), 6-(methylsulfanyl)hexyl GSL (6), and benzyl GSL (7). Additionally, pent-4-enyl- and hex-5-enyl ITCs were detected in the volatile extracts. However, their corresponding GSLs were not detected using UHPLC-DAD-MS/MS. Thus, they are suggested to be formed during GC-MS analysis via thermolysis of 5-(methylsulfinyl)pentyl- and 6-(methylsulfinyl)hexyl ITCs, respectively. Volatile isolates were tested for their cytotoxic activity using MTT assay. EXT and MHG showed the best cytotoxic activity against human lung cancer cell line A549 during an incubation time of 72 h (IC50 18.8, and 33.5 µg/mL, respectively), and against breast cancer cell line MDA-MB-231 after 48 h (IC50 6.0 and 11.8 µg/mL, respectively). These activities can be attributed to the ITCs originating from 3 and 4.

Glucosinolates in wild and cultivated Brassica montana Pourret (Brassicaceae) from southern France.

The glucosinolate (GL) profiles of wild and cultivated Brassica montana Pourret (seed, stem, leaf, root) from southern France were established using LC-MS analysis. In this investigation we have confirmed the presence of 9 known GLs: but-3-enyl- (1), prop-2-enyl- (2), pent-4-enyl- (3), (2R)-2-hydroxybut-3-enyl- (4), 4-hydroxyindol-3-ylmethyl- (5), 4-(methylsulfinyl)butyl- (6), 4-(methylsulfanyl)butyl- (7), 1-methoxyindol-3-ylmethyl- (8), and indol-3-ylmethyl (9) GL. In addition, we tentatively identified for the first time the presence in the plant of 1-methylpropyl GL (10) in all plant parts. In addition, we have pointed out differences in GL profiles between plant organs and between wild and cultivated B. montana.

Simultaneous extraction and separation of oil, proteins, and glucosinolates from Moringa oleifera seeds.

Moringa oleifera is a worldwide cultivated edible and medicinal plant. Its seeds are rich in oil, proteins, and glucosinolates. A practical method was developed to simultaneously extract and separate the three groups of substances from M. oleifera seeds. Smashed seed material was loaded into columns with petroleum ether: ethanol 8:2 (PE-ethanol) and eluted sequentially with 4.8-fold PE-ethanol to extract oil, and 10.8-fold water to extract proteins and glucosinolates. More than 95% of oil, proteins, and glucosinolates were extracted. The extracts were separated automatically into ether (oil) phase and ethanol aqueous phase. The latter was further separated into proteins and glucosinolates by 70% ethanol precipitation. The main glucosinolate was identified by LC-MS as GLC (4-α-rhamnopyranosyloxy-benzyl glucosinolate). After purification, 22.3 g refined oil, 33.0 g proteins, and 5.5 g purified GLC from 100 g M. oleifera seeds were obtained. This study provides a simple and high-efficient method to utilize M. oleifera seeds.

Bioavailability of Sulforaphane Following Ingestion of Glucoraphanin-Rich Broccoli Sprout and Seed Extracts with Active Myrosinase: A Pilot Study of the Effects of Proton Pump Inhibitor Administration.

We examined whether gastric acidity would affect the activity of myrosinase, co-delivered with glucoraphanin (GR), to convert GR to sulforaphane (SF). A broccoli seed and sprout extract (BSE) rich in GR and active myrosinase was delivered before and after participants began taking the anti-acid omeprazole, a potent proton pump inhibitor. Gastric acidity appears to attenuate GR bioavailability, as evidenced by more SF and its metabolites being excreted after participants started taking omeprazole. Enteric coating enhanced conversion of GR to SF, perhaps by sparing myrosinase from the acidity of the stomach. There were negligible effects of age, sex, ethnicity, BMI, vegetable consumption, and bowel movement frequency and quality. Greater body mass correlated with reduced conversion efficiency. Changes in the expression of 20 genes in peripheral blood mononuclear cells were evaluated as possible pharmacodynamic indicators. When grouped by their primary functions based on a priori knowledge, expression of genes associated with inflammation decreased non-significantly, and those genes associated with cytoprotection, detoxification and antioxidant functions increased significantly with bioavailability. Using principal components analysis, component loadings of the changes in gene expression confirmed these groupings in a sensitivity analysis.

Combined effect of ultrasound treatment and exogenous phytohormones on the accumulation of bioactive compounds in broccoli florets.

Postharvest treatments such as wounding, ultrasound (US) and the exogenous application of ethylene (ET) and methyl jasmonate (MJ) have been studied as an effective tool to improve the content of secondary metabolites in fresh produce. The present study evaluated the immediate and late response (storage for 72 h at 15 °C) to US treatment (20 min, frequency 24 kHz, amplitude 100 µm) alone and combined with exogenous MJ (250 ppm) and/or ET (1000 ppm) on glucosinolates, isothiocyanates, phenolic compounds and ascorbic acid content in broccoli florets. US treatment increased the extractability of glucosinolates [glucoraphanin (795%), 4-hydroxy glucobrassicin (153%), glucobrassicin (78.6%)] and phenolics [1-sinapoyl-2-feruloylgentiobiose (57.23%)] as compared with the control (CT). The combined application of MJ and US in broccoli florets, induced a synergistic effect on the accumulation of 4-hydroxy glucobrassicin (187.1%), glucoerucin (111.92%), gluconasturtiin (755.9%), neoglucobrassicin (232.8%), 3-O-caffeoylquinic acid (73.4%), 1-sinapoyl-2-ferulolylgentiobiose (56.0%), and 1,2,2-trisinapoylgentiobiose (136.7%) at 72 h of storage. Interestingly, when the three stressors were applied together the synergistic effect of US + MJ observed on the accumulation of glucosinolates and phenolics was repressed. In general, the ascorbic acid content was not affected by US treatment and decreased in most samples during storage. However, when MJ + ET were applied, the content of total ascorbic acid was significantly reduced in CT + MJ + ET and US + MJ + ET samples after 72 h of storage by 53.4% and 86.6%, respectively, as compared with CT 0 h samples. Based on the results herein obtained, the application of US can be an effective tool to enhance the extractability of certain glucocosinolate and phenolic compounds in broccoli. Moreover, due to the synergistic effect observed on the accumulation of bioactive compounds, the combined application of US and MJ could be a practical approach to yield higher levels of glucosinolates and phenolic compounds in broccoli during storage.

Investigation into the removal of glucosinolates and volatiles from anthocyanin-rich extracts of red cabbage.

The aim of the present article was an in-depth characterization of cyanidine-rich red cabbage extracts and the identification of challenges emerging during the purification of their pigments. Two extraction procedures using either hot acidified or temperate water at its genuine pH were compared. LC-MS analyses revealed 20 mostly acylated anthocyanins, five aliphatic glucosinolates, and four indolic glucosinolates as non-volatile constituents. In addition, volatiles were characterized by HS-SPME-GC-MS. Whereas the glycosidic precursors do not impair the sensory properties, their enzymatic degradation products may evoke unpleasant flavors. The crude pigment extract obtained with hot acidified water contained low concentrations of C6 aldehydes, isothiocyanates, nitriles, and sulfides, and was selected for purification experiments. Amberlite XAD 16 HP, polyamide, chitosan, and lignosulfonate were used as adsorbents and flocculants. Particularly, Amberlite and lignosulfonate treatment diminished the content of glucosinolates and volatiles. Interestingly, indolic glucosinolates and acylated anthocyanins showed similar behavior in all purification procedures performed.

Hydrogen Sulfide (H2S) Releasing Capacity of Isothiocyanates from Moringa oleifera Lam.

Moringa oleifera Lam. is rich in phytochemical compounds especially glucosinolates (GSs) and isothiocyanates (ITCs), which are active compounds for cancer chemoprevention benefits of Brassicaceae vegetables. In this study, we determined the total contents of GSs and ITCs and their specific profiles in different Moringa tissues including seeds, stems, leaves and roots. Seeds (seeds with shell and seed kernel) showed significantly higher levels of total GSs and ITCs than that of other Moringa tissues. The hydrogen sulfide (H2S) releasing capacity of total ITCs extracted from different Moringa tissues was determined by lead (II) acetate assay in 24-well plates. The H2S releasing capacity of different Moringa tissues were evaluated and compared. Moringa seeds showed the highest H2S releasing capacity, followed by roots, leaves and stems. Our results suggest that Moringa based foods may exhibit health benefits due to its GSs and ITCs contents that are the precursors for H2S, in addition to the recognized action mechanisms of ITCs.

Glucoraphanin: a broccoli sprout extract that ameliorates obesity-induced inflammation and insulin resistance.

Obesity is a low-grade sustained inflammatory state that causes oxidative stress in different metabolic tissues, which leads to insulin resistance and nonalcoholic fatty liver disease (NAFLD). Particularly, obesity-induced metabolic endotoxemia plays an important role in the pathogenesis of insulin resistance and inflammation. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key regulator of antioxidant signaling that serves as a primary cellular defense against the cytotoxic effects of oxidative stress. Pharmacological stimulation of Nrf2 mitigates obesity and insulin resistance in mice; however, Nrf2 activators are not clinically available due to biosafety concerns. A recent study demonstrated that glucoraphanin, a precursor of the Nrf2 activator sulforaphane, ameliorates obesity by enhancing energy expenditure and browning of white adipose tissue, and attenuates obesity-related inflammation and insulin resistance by polarizing M2 macrophages and reducing metabolic endotoxemia. Thus, this review focuses on the efficiency and safety of glucoraphanin in alleviating obesity, insulin resistance, and NAFLD. Abbreviations: ALT, Alanine aminotransferase; AMPK, AMP-activated protein kinase; ATMs, Adipose tissue macrophages; BAT, Brown adipose tissue; CDDO-Im, 2-cyano-3,12-dioxoolean-1,9-dien-28-oic acid-imidazolide; CDDO-Me, CDDO-methyl ester; DIO, High-fat-diet-induced obese; FFA, Free fatty acid; FGF, Fibroblast growth factor; GTP, Glutamyl transpeptidase; HFD, High-fat diet; IKKß, Inhibitor of κB-kinase ß; IL, Interleukin; JNK, C-Jun N-terminal kinase; KD, Knockdown; Keap1, Kelch-like ECH-associated protein 1; KO, Knockout; LPS, Lipopolysaccharide; NADPH, Nicotinamide adenine dinucleotide phosphate; NAFLD, Non-alcoholic fatty liver disease; NF-κB, Nuclear factor-κB; Nrf2, Nuclear factor E2-related factor 2; ROS, Reactive oxygen species; T2D, Type 2 diabetes; TLR, Toll-like receptor; TNF, tumor necrosis factor; UCP, Uncoupling protein; WAT, White adipose tissue.

The Diversity of Chemoprotective Glucosinolates in Moringaceae (Moringa spp.).

Glucosinolates (GS) are metabolized to isothiocyanates that may enhance human healthspan by protecting against a variety of chronic diseases. Moringa oleifera, the drumstick tree, produces unique GS but little is known about GS variation within M. oleifera, and even less in the 12 other Moringa species, some of which are very rare. We assess leaf, seed, stem, and leaf gland exudate GS content of 12 of the 13 known Moringa species. We describe 2 previously unidentified GS as major components of 6 species, reporting on the presence of simple alkyl GS in 4 species, which are dominant in M. longituba. We document potent chemoprotective potential in 11 of 12 species, and measure the cytoprotective activity of 6 purified GS in several cell lines. Some of the unique GS rank with the most powerful known inducers of the phase 2 cytoprotective response. Although extracts of most species induced a robust phase 2 cytoprotective response in cultured cells, one was very low (M. longituba), and by far the highest was M. arborea, a very rare and poorly known species. Our results underscore the importance of Moringa as a chemoprotective resource and the need to survey and conserve its interspecific diversity.

Separation and Quantification of Four Main Chiral Glucosinolates in Radix Isatidis and Its Granules Using High-Performance Liquid Chromatography/Diode Array Detector Coupled with Circular Dichroism Detection.

As chemical drugs, separation and quantification of the specific enantiomer from the chiral compounds in herbal medicines are becoming more important. To clarify the chemical characterization of chiral glucosinolates-the antiviral active ingredients of Radix Isatidis, an optimized efficient method of HPLC-UV-CD was developed to simultaneously separate and quantify the four main chiral glucosinolates: progoitrin, epiprogoitrin, and R,S-goitrin. The first step was to determine progoitrin, epiprogoitrin, and R,S-goitrin using HPLC-UV, and then determine the R-goitrin and S-goitrin by coupling with CD detection. Subsequently, through the linear relations between anisotropy factor (g factor) and the percent optical purity of R-goitrin, the contents of R-goitrin and S-goitrin from the R,S-goitrin mixture were calculated separately. Furthermore, the chemical composition features of the four chiral glucosinolates in 37 samples from crude drugs, decoction pieces, and granules of R. Isatidis were conducted. The total content of the four glucosinolates was obviously higher in crude drugs, and the variance character of each glucosinolate contents was different. In summary, the accurate measurement method reported here allows for better control of the internal quality of R. Isatidis and its granules and provides a powerful approach for the analysis of other chiral components in traditional Chinese medicines.