Variation in Glucosinolate Accumulation among Different Sprout and Seedling Stages of Broccoli (Brassica oleracea var. italica)

Cooked Broccoli Alters Cecal Microbiota and Impacts Microbial Metabolism of Glucoraphanin in Lean and Obese Mice

SCOPE

Brassica vegetables contain unique compounds known as glucosinolates (GSLs), which, when hydrolyzed by plant or microbial myrosinase, form bioactive isothiocyanates (ITCs) that offer health benefits to the host. The present study evaluated the impact of cooked broccoli (broccoli myrosinase inactivated) consumption on cecal microbial metabolism of glucoraphanin (GRP) in lean and obese mice and characterized the changes in cecal microbiota following broccoli-containing diets.

METHODS AND RESULTS

Twenty lean and 20 diet-induced obese (DIO) mice were randomized to consume control or cooked broccoli supplemented diets for 7 days. Cooked broccoli consumption increased ex vivo microbial GRP hydrolysis by cecal contents collected from lean and obese mice, led to increased production of sulforaphane (SF), sulforaphane-cysteine (SF-CYS), total ITC, and colonic NAD(P)H: Quinone Oxidoreductase (NQO1) activity. Further investigation revealed increased abundance of health-promoting gut microbiota, including Lachnospiraceae NK4A136 group and Dubosiella newyorkensis, following broccoli-containing diets. The Peptococcaseae family, the Blautia genus, and an amplicon sequence variation (ASV) from the Oscillospiraceae family exhibited negative correlation with total ITC production.

CONCLUSION

These finding suggest that cooked broccoli consumption enhances microbial GRP hydrolysis to produce more bioactive ITCs and inform future strategies toward altering microbial GSL metabolism to promote gut health in both lean and obese individuals.

Physiological, morphological and chemical changes in pea seeds under different storage conditions

The loss of germination, viability, and vigor of seeds under storage conditions are the main causes of the need to multiply the seed material for leguminous crops. For crop establishment, seeds obtained in propagation fields are usually used, and the coating comes from the basic seed. In the case of leguminous species, the seeds quickly lose their viability, and in accordance with international regulations, for legumes, the number of seeds increases only in the first year of propagation. Therefore, the main objective of this study was to assess the effects of variations in the storage period, temperature and humidity on the morphophysiological and chemical traits of two pea seed varieties (Gloriosa and Kelvedon Wonder). The pea seeds were harvested at the end of June 2017, 2018 and 2019 and stored for 32, 20 and 8 months at T = 4 °C and H = 8%; T = 4 °C and H = 12%; T = 8 °C and H = 8%; T = 8 °C and H = 12%; and T = 22 °C and H = 65%. The results of the morphological, chemical, and biochemical analyses showed that the highest germination rate; hypocotyl length; radicle length; lipid content; dietetic fiber content; caloric value; and Ca, Mg, K, Na, Fe and Zn contents were detected in the Gloriosa and KW seeds stored for 8 months at 4 °C and 8% humidity. Analysis of the experimental data by statistical methods revealed that increasing the storage time had an individual significant negative influence only on the germination rate of both pea varieties and on the hypocotyl length and radicle length of the KW variety, while humidity and temperature variation had individual significant influences on the lipid content. The significant effects of humidity and temperature on the germination rate, hypocotyl length and root length of KW plants were also determined. For the remaining morphophysiological and chemical traits of pea seeds, the individual and combined effects of the factors were not statistically significant. Furthermore, the comparison of means using the Tukey test showed that storage conditions related to temperature and humidity generally used by farmers (T = 22 °C × H = 65%) did not significantly affect the majority of the nutritional properties of the pea seeds. However, maintaining pea seeds under these conditions for a longer period of time significantly affects seed germination and vigor.

Brassica oleracea var italica and Their By-Products as Source of Bioactive Compounds and Food Applications in Bakery Products

Broccoli (Brassica oleracea var. italica) is one of the most consumed cruciferous crops in the world, with China and Spain acting as the main producers from outside and within the EU, respectively. Broccoli florets are edible, while the leaves and stalks, discarded in the field and during processing, are by-products. Therefore, the objective of this study was to conduct a comprehensive review of the nutrient and phytochemical composition of broccoli and its by-products, as well as its beneficial effects. In addition, the study highlights the revalorization of broccoli by-products through innovative green technologies and explores their potential use in bakery products for the development of functional foods. The studies suggested that broccoli is characterized by a high content of nutrients and bioactive compounds, including vitamins, fiber, glucosinolates, and phenolic compounds, and their content varied with various parts. This high content of value-added compounds gives broccoli and its various parts beneficial properties, including anti-cancer, anti-inflammatory, antioxidant, antimicrobial, metabolic disorder regulatory, and neuroprotective effects. Furthermore, broccoli and its by-products can play a key role in food applications by improving the nutritional profile of products due to their rich content of bioactive compounds. As a result, it is essential to harness the potential of the broccoli and its by-products that are generated during its processing through an appropriate agro-industrial revalorization, using environmentally friendly techniques.

Chromosome-scale reference genome of broccoli (Brassica oleracea var. italica Plenck) provides insights into glucosinolate biosynthesis

Broccoli (Brassica oleracea var. italica Plenck) is an important vegetable crop, as it is rich in health-beneficial glucosinolates (GSLs). However, the genetic basis of the GSL diversity in Brassicaceae remains unclear. Here we report a chromosome-level genome assembly of broccoli generated using PacBio HiFi reads and Hi-C technology. The final genome assembly is 613.79 Mb in size, with a contig N50 of 14.70 Mb. The GSL profile and content analysis of different B. oleracea varieties, combined with a phylogenetic tree analysis, sequence alignment, and the construction of a 3D model of the methylthioalkylmalate synthase 1 (MAM1) protein, revealed that the gene copy number and amino acid sequence variation both contributed to the diversity of GSL biosynthesis in B. oleracea. The overexpression of BoMAM1 (BolI0108790) in broccoli resulted in high accumulation and a high ratio of C4-GSLs, demonstrating that BoMAM1 is the key enzyme in C4-GSL biosynthesis. These results provide valuable insights for future genetic studies and nutritive component applications of Brassica crops.

Unravelling Glucoraphanin and Glucoerucin Metabolism across Broccoli Sprout Development: Insights from Metabolite and Transcriptome Analysis

Variations in the concentration of glucoraphanin (GRA) and glucoerucin (GER), as well as the corresponding breakdown products, isothiocyanates (ITCs) and nitriles, were investigated during the growth of broccoli sprouts. The concentrations of GRA and GER decreased sharply from 33.66 µmol/g to 11.48 µmol/g and 12.98 µmol/g to 8.23 µmol/g, respectively, after seed germination. From the third to the seventh day, both GRA and GER were maintained as relatively stable. The highest concentrations of sulforaphane (17.16 µmol/g) and erucin (12.26 µmol/g) were observed on the first day. Hereafter, the concentrations of nitrile hydrolyzed from GRA or GER were higher than those of the corresponding ITCs. Moreover, the ratio of sulforaphane to sulforaphane nitrile decreased from 1.35 to 0.164 from 1 d to 5 d, with a similar trend exhibited for erucin/erucin nitrile after 2 d. RNA-seq analysis showed that BolMYB28 and BolCYP83A1, involved in aliphatic glucosinolate (GSL) biosynthesis, remained largely unexpressed until the third day. In contrast, the genes operating within the GSL-myrosinase hydrolysis pathway were highly expressed right from the beginning, with their expression levels increasing significantly after the third day. Additionally, we identified two BolESPs and six BolNSPs that might play important roles in promoting the production of nitriles during the development of broccoli sprouts.

The preventive effects of broccoli bioactives against cancer: Evidence from a validated rat glioma model

The aggressive and incurable diffuse gliomas constitute 80% of malignant brain tumors, and patients succumb to recurrent surgeries and drug resistance. Epidemiological research indicates that substantial consumption of fruits and vegetables diminishes the risk of developing this tumor type. Broccoli consumption has shown beneficial effects in both cancer and neurodegenerative diseases. These effects are partially attributed to the isothiocyanate sulforaphane (SFN), which can regulate the Keap1/Nrf2/ARE signaling pathway, stimulate detoxifying enzymes, and activate cellular antioxidant defense processes. This study employs a C6 rat glioma model to assess the chemoprotective potential of aqueous extracts from broccoli seeds, sprouts, and inflorescences, all rich in SFN, and pure SFN as positive control. The findings reveal that administering a dose of 100 mg/kg of broccoli sprout aqueous extract and 0.1 mg/kg of SFN to animals for 30 days before introducing 1 × 104 cells effectively halts tumor growth and progression. This study underscores the significance of exploring foods abundant in bioactive compounds, such as derivatives of broccoli, for potential preventive integration into daily diets. Using broccoli sprouts as a natural defense against cancer development might seem idealistic, yet this investigation establishes that administering this extract proves to be a valuable approach in designing strategies for glioma prevention. Although the findings stem from a rat glioma model, they offer promising insights for subsequent preclinical and clinical research endeavors.

High Growing Temperature Changes Nutritional Value of Broccoli (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.) Seedlings

High temperature (HT) causes physiological and biochemical changes in plants, which may influence their nutritional potential. This study aimed to evaluate the nutritional value of broccoli seedlings grown at HT on the level of phytochemicals, macro- and microelements, antioxidant capacity, and their extracts' in vitro cytotoxicity. Total phenols, soluble sugars, carotenoids, quercetin, sinapic, ferulic, p-coumaric, and gallic acid were induced by HT. Contrarily, total flavonoids, flavonols, phenolic acids, hydroxycinnamic acids, proteins, glucosinolates, chlorophyll a and b, and porphyrins were reduced. Minerals As, Co, Cr, Hg, K, Na, Ni, Pb, Se, and Sn increased at HT, while Ca, Cd, Cu, Mg, Mn, and P decreased. ABTS, FRAP, and β-carotene bleaching assay showed higher antioxidant potential of seedlings grown at HT, while DPPH showed the opposite. Hepatocellular carcinoma cells were the most sensitive toward broccoli seedling extracts. The significant difference between control and HT-grown broccoli seedling extracts was recorded in mouse embryonal fibroblasts and colorectal carcinoma cells. These results show that the temperature of seedling growth is a critical factor for their nutritional value and the biological effects of their extracts and should definitely be taken into account when growing seedlings for food purposes.