Figures (6)  Tables (3)

    • Figure 1. 

      Glucosinolate structure and type.

    • Figure 2. 

      Mechanisms in Brassicaceae synthesize GSLs: The biosynthesis of GSLs consists of three phases, including chain elongation, GSL core structure, and secondary modification. Met, methionine; Phe, phenyl alanine; Trp, tryptophan; BCAT, branched-chain amino acid aminotransferase; MAM, methylthioalkylmalate synthase; IPMI, isopropylmalate isomerase; IPMDH, isopropylmalate dehydrogenase; CYP79F1, cytochrome P450 79F1; CYP79F2, cytochrome P450 79F2; CYP79A2, cytochrome P450 79A2; CYP83A1, cytochrome P450 83A1; CYP83A2, cytochrome P450 83A2; CYP83B1, cytochrome P450 83B1; GSTU20, glutathione-S-transferases TAU 20; GSTF11, glutathione-S-transferases F11; GGP1, gamma-glutamyl peptidases 1; GGP3, gamma-glutamyl peptidases 3; SUR1, super root 1; UGT74C1, UDP-glycosyl transferase 74C1; UGT74B1, UDP-glycosyl transferase 74B1; SOT16, sulfotransferase 5a; SOT16, sulfotransferase 5c; SOT16, sulfotransferase 5b; FMO, flavin monooxygenase glucosinolate S-oxygenase; AOP2, alkenyl hydroxalkyl-producing 2; GS-OH, 2-oxoglutarate-dependent dioxygenase; CYP81F1, cytochrome P450 81F1; CYP81F2, cytochrome P450 81F2; CYP81F3, cytochrome P450 81F3; CYP81F4, cytochrome P450 81F4; IGMT1, indole GSL O-methyltransferase 1; IGMT2, indole GSL O-methyltransferase 2; IGMT5, indole GSL O-methyltransferase 5.

    • Figure 3. 

      Glucosinolates hydrolysis in Brassica plant cells. NSP, nitrile specifier proteins; ESP, epithiospecifier proteins; TSP, thiocyanate specifier proteins.

    • Figure 4. 

      Factors influencing the glucosinolate content of Brassica.

    • Figure 5. 

      Strategies to improve glucosinolate production in Brassicaceae.

    • Figure 6. 

      Regulatory network of GSLs metabolism and sustainable managements for GSLs improvement in Brassicaceae.

    • Common nameChemical name
      (side chain R)      		Molecular weight (g·mol−1)Prominently observed inBenefits to health or toxicityRef.
      Aliphatic glucosinolate
      Three carbon chain length
      Sinigrin2-Propenyl GSL359Mustard green, white and red cabbage, cauliflower, kale and kohlrabiAnticarcinogenic, antimicrobial, anti-inflammatory, wound-healing properties, and antioxidant activity[9−13]
      Glucoiber verin3-Methylthio propyl GSL407White and red cabbage,
      cauliflower and kale      		Antimicrobial activity[9,11−14]
      Glucoiber in3-Methylsulfi nylpropyl GSL423Cabbage, broccoli and cauliflowerAntimicrobial activity[9,11−14]
      Four carbon chain length
      Gluconapi n3-Butenyl GSl373Chinese cabbage, mustard spinach, cabbage, broccoli, cauliflower and rapeseedAnticarcinogenic activity, prevention of postprandial hypertriglyceridemia and antimicrobial activity[9,11−13,
      18,21,22]
      Progoitrin (2R)2-Hydroxy- 3-butenyl GSL389Chinese cabbage, mustard spinach, turnip, broccoli, cauliflower and rapeseed
      		Antiviral activity, effect of goitrogens, and suppression of the synthesis of thyroid hormones[9,11−13,
      15−17]
      Glucoeruc in4-Methylthio butyl GSL421Garden rocketAnticarcinogenic activity, antioxidant activity and anti-obesity activity[9,11−13,
      23−25]
      Glucorap hanin4-Methylsulfi nylbutyl GSL437Broccoli, garden rocket, cauliflower and kohlrabiAnti-inflammatory activity, recovery and prevention of muscle atrophy and alcohol intolerance preventive[9,11−13,
      26−28]
      Five carbon chain length
      Glucobras sicanapin4-Pentenyl GSL387Chinese cabbage, turnip, turnip green and swedeAntimicrobial activity[9,11−13,18]
      Glucoalyssin5-Methylsulfi nylpentyl GSL451Ethiopian mustard
      		Anticarcinogenic activity and antimicrobial activity[11−14,29,30]
      Aromatic glucosinolate
      Gluconast urtiin2-Phenethyl GSL423Watercress and horseradishAnticarcinogenic activity, cardioprotective and neuroprotective activity[11−13,22,
      31,32]
      Glucotrop aeolinBenzyl GSL409Red cabbageAntidiabetic, neuroprotective activity and prevention of
      multiple sclerosis
      [11−13,22,33]
      Indole glucosinolate
      Glucobras sicin3-lndolyl methyl GSL448Green cabbage, broccoli, chinese and red cabbageImpediment to cancer in prostate[11−13,19,20]
      Neogluco brassicin1-Methoxy-3- indolymethyl GSL478Red cabbage, Chinese cabbage, broccoli, and green cabbageInhibition of cancer in prostate[11−13,19,20]

      Table 1. 

      Major glucosinolates and their health benefits in Brassicaceae.

    • VariablePlant speciesChange in glucosinolate levelRef.
      Abiotic factors
      Soil salinityBrassica oleracea var. italica (broccoli) and B. rapa var. pekinensis (Chinese cabbage)Increase total GSLs (40, 80 mM)[44]
      R. sativus (radish), Brassica oleracea var. botrytis
      (cauliflower) and B. oleracea var. italica (broccoli)      		Increase total GSLs with reduced water[56]
      Water availabilityB. oleracea var. capitata (cabbage), Brassica napus (rapeseed) and Brassica oleracea var. italica (Broccoli)Increase total GSLs with severe drought[44]
      Brassica carinata (Ethiopian mustard) and B. oleracea
      var. gemmifera (Brussels sprouts)      		No effect under mild drought[44,56]
      B. rapa var. rapa (turnip)Increase total GSLs with mild drought[44]
      Brassica oleracea var. capitata (cabbage) and
      Arabidopsis thaliana (thale cress)      		Decrease total GSLs under mild and severe drought[44]
      Temperature stressB. oleracea var. italica (broccoli), B. oleracea var.
      botrytis (cauliflower)      		At a moderate temperature of 14 °C and increase total GSLs[56]
      B. oleracea var. capitata (cabbage), B. oleracea L. var. gemmifera (Brussels sprouts) and B. oleracea var.
      acephala (kale)      		Total GSLs diminish as temperature rises[61]
      B. napus (swede)Progoitrin and glucoberteroin should be increased to 21 °C[113]
      B. rapa var. pekinensis (Chinese cabbage)Vary the total GSLs from 21 to 34 °C[44]
      B. oleracea var. italica (broccoli) and B. oleracea var.
      botrytis (cauliflower)      		Increase overall GSLs under bright conditions
      (450 μmol·m−2·s−1)      		[56]
      B. oleracea var. italica (broccoli) and B. oleracea var.
      botrytis (cauliflower)      		Reduce glucoraphanin levels during harvest using high light[44]
      Light intensityB. oleracea var. italica (broccoli)
      		Diminish overall GSLs with light[44]
      B. oleracea var. capitata (cabbage) and B. oleracea var. gemmifera (Brussels sprouts)Variation in total and indole GSLs with respect to light intensity and duration[61]
      Cardamine fauriei (Ezo-wasabi)Total GSLs increase; red + blue luminescence[68]
      Brassica oleracea var. acephala (kale)Change in total and indole GSLs with respect to light intensity and day length[61]
      Arabidopsis thaliana (thale cress)Light increases total GSLs, while darkness reduces total GSLs[44]
      Sulfur applicationB. oleracea var alboglabra (Chinese kale)Blue light diminishes gluconapin levels[114]
      B. oleracea var. italica (broccoli)Enhance indole and alkyl GSLs (60 mg of S plant−1)[56]
      Raphanus sativus (radish)Boost alkenyl GSLs (30 mg·plant−1)[56]
      Brassica rapa var. rapa (turnip)Promote overall GSLs (60 kg S ha−1)[44]
      Potassium applicationBrassica rapa var. rapa (turnip)Decrease total GSLs with K+ deficiency[44]
      Arabidopsis thaliana (thale cress)Increase overall GSLs when K+ is lacking[44]
      Nitrogen applicationB. oleracea var. botrytis (cauliflower), B. oleracea var.
      italica (broccoli) and Raphanus sativus (radish)      		Increase total GSLs by decreasing nitrogen[56]
      Brassica oleracea var. italica (broccoli)Increase average GSLs while decreasing N (1 g of
      N plant−1)      		[44]
      Brassica oleracea var. italica (broccoli)Raise the overall GSLs by 5.2 mM Se[44]
      Selenium applicationRaphanus sativus (radish)Enrich the soil with total GSLs and glucoraphanin[81]
      Pre-harvest factors
      Brassica oleracea var. italica (broccoli)Increase indole GSLs in immature florets, increase glucoraphanin between transplanting and harvest[61,115]
      Developmental stage
      at harvest      		B. oleracea var. capitata (cabbage), B. oleracea var. gemmifera (Brussels sprouts), B. oleracea var. botrytis (cauliflower) and B. oleracea var. acephala (kale)Increase glucoraphanin between transplanting and harvest[61]
      Seasonal variationB. oleracea var. italica (broccoli) and Brassica oleracea
      var. botrytis (cauliflower)      		Enhance overall GSLs in spring and autumn[56]
      B. oleracea var. capitata (cabbage) and B. oleracea var. gemmifera (Brussels sprouts)Increase glucoiberin and glucobrassicin in spring[84]
      Agricultural practicesB. oleracea var italica (broccoli)The levels of 3-indolylmethyl-GSL were considerably elevated in crops grown organically[91]
      Post-harvest factors
      StorageB. oleracea var. italica (broccoli)The content of 4-methylsulfinylbutyl-GSL in florets exhibited an increase subsequent to a 6-d storage period, which was followed by a decrease in temperature[94]
      Processing and minimal processingB. oleracea var. italica (broccoli)An increase of 490% in total GSLs, 4,200% in 4-hydroxy-3-indolylmethyl-GSL, and the rise of 1,300% in 1-methoxy-3-indolylmethyl-GSL was reported after 24 h of incubation at a temperature of 20 °C[103]
      PackagingBrassica oleracea var. italica (broccoli)Compared to fresh florets, storage in a regulated atmosphere consisting of 0.5% O2, 20% CO2 and air. resulted in a 21%–42% increase in total GSL[112]

      Table 2. 

      Impact of abiotic stress, pre-harvest, and post-harvest factors on Brassicaceae glucosinolate levels.

    • ApproachInvoved processStrategyGene nameTarget speciesSource speciesEffect on GSLsRef.
      Modulation of GSL biosynthesisSide chain elongationKOMAM1Chinese cabbageArabidopsis thalianaIncreased aliphatic GSL (3-butenyl-GSL, 4-pentenyl-GSL)[129]
      Glucone formationKOCYP79F1Chinese cabbageArabidopsis thalianaIncreased levels of 2-hydroxy-4-pentenyl-GSL, indol-3-ylmethyl-GSL, 4-methoxy-indol-3-ylmethyl-GSL, decreased concentrations of 3-butenyl-GSL and 4-pentenyl-GSL, and increased concentration of 4 hydroxyindol-3-ylmethyl-GSL[140]
      Glucone formationKOCYP83A1Chinese cabbageArabidopsis thalianaIncreased aliphatic GSL[129]
      Secondary
      modification      		OEFMOGS-OXBrassica rapassp. rapaBrassica rapa
      ssp. rapa      		Elevated aliphatic GSL[130]
      Glucone formationOECYP79B2, CYP79B3, CYP83B1 Brassica rapaArabidopsis thalianaIncreased indolic GSL[131,141]
      Glucone formationOEUGT74B1 B. napusBrassica napusElevate aliphatic GSL and indolic GSL[132]
      Ablation of GSL hydrolysisGSL hydrolysisCo- expressionMyr1.Bn1B. napusBrassica napusSeeds' myrosinase storing idioblasts were eliminated[133]
      Inhibition of GSL transportGSL transportKOGTRB. rapaBrassica rapaLowered GSL content in seedlings[135]
      Redirection of metabolic flux to GSLEngineering metabolic fluxMutationTDCBrassica napusCatharanthus roseusDiminished indolic GSL in both seedlings and entire plants[136]
      Transcriptional regulationGSMYB28Brassica oleracea var. alboglabraBrassica oleracea var. alboglabraRaised in aliphatic GSLs[137]
      Modulation of GSL transcription regulationTranscriptional regulationOEMYB28Brassica rapaBrassica rapaAliphatic GSL and indolic GSL are elevated[138]
      Transcriptional regulationOEMYB29Brassica oleraceaBrassica oleraceaEnhanced aliphatic GSL concentration (2-propenyl glucoraphanin GSL)[139]

      Table 3. 

      Metabolic engineering of glucosinolate in Brassicaceae.