Figures (4)  Tables (1)

    • Figure 1. 

      Biosynthetic pathway of caffeine. (a) Synthesis of the precursor substance guanosine. (b) The Synthetic Pathway from guanosine to caffeine. ADK: adenosine kinase; PNP: purine nucleoside phosphorylase; APT: adenine phosphoribosyltransferase; AMPD: adenosine 5'-monophosphate deaminase; IMPDH: inosine monophosphate dehydrogenase; XMT: xanthosine methyltransferase; NS: N-methylnucleosidase; TS: thymidylate synthase; CS: caffeine synthase.

    • Figure 2. 

      Biosynthetic pathway of terpenoid skeletons. (a) The synthesis of the common precursors of all terpenoids, isopentenylpyrophosphate (IPP) and dimethylallyl pyrophosphate (DMAPP). (b) The pathway for IPP and DMAPP to synthesize terpenoid skeletons through terpene synthases. ACAT: acyl coenzyme A-cholesterol acyltransferase; HMGCS: 3-Hydroxymethylglutaryl coenzyme A synthase; HMGCR: 3-hydroxy-3-methylglutaryl coenzyme A reductase; M3K: mevalonate-3-kinase; MVK: mevalonate kinase; M3P5K: mevalonate-3-phosphate-5-kinase; PMVK: phosphomevalonate kinase; MVD: diphosphomevalonate decarboxylase; IPK: isopentenyl phosphate kinase; IDI: isopentenyl diphosphate isomerase; DXS: 1-Deoxy-D-xylulose-5-phosphate synthase; DXR: 1-deoxy-D-xylulose-5-phosphate reductoisomerase; ispD: 2-C-methyl-D-erythritol 4-phosphate cytidylyltransferase; ispDF: 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase; ispE: 4-diphosphocytidyl-2-C-methyl-D-erythritol kinase; ispF: 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase; gcpE: (E)-4-hydroxy-3-methylbut-2-enyl-diphosphate synthase; ispH: (E)-4-Hydroxy-3-methylbut-2-enyl diphosphate reductase.

    • Figure 3. 

      Biosynthesis pathways of some common phenylpropanoids, which are synthesized through the tyrosine pathway and the phenylalanine pathway. C2H: coumarate-2-hydroxylase; PAL: phenylalanine ammoniase; 4CL: 4-coumarate: coenzyme A ligase; C4H: cinnamic acid 4-hydroxylase; CPR: cytochmme P450 reductase; IL4I1: Interleukin-4-Induced-1; TAL: tyrosine aminolyase; STS: Stilbene synthase; Ubic: chorismate--pyruvate lyase; CAR: carboxylic acid reductase; Sfp: phosphopantetheinyl transferase; ADH: alcohol dehydrogenase; UGT: uridine diphosphate glycosyltransferase; TYRDC-2: 4-hydroxyphenylacetaldehyde synthase; OMT: o-methyltransferase; CCR: cinnamoyl-CoA reductase; HCT: hydroxycinnamoyl transferase; C3'H: p-Coumaroyl-shikimic acid/quinic acid 3′-hydroxylase.

    • Figure 4. 

      Biosynthetic pathway of plant polysaccharides.Various sugar nucleotides form different repeating units, which are synthesized into polysaccharides under the action of GTs. SPS: sucrose phosphate synthase; SPP: sucrose phosphate phoshatase; SUS: sucrosesynthase; UGPase: UDP-glucose pyrophosphorylase; UGE: UDP-glucose-4-epimerase; UGD: UDP-D-galactosedehydrogenase; UGDH: UDP-glucose dehydrogenase; UXS: UDP-glucuronic acid decarboxylase; GAE: UDP-glucoseA-4-epimerase; UXE: UDP-D-xylosel-4-epimeras; UAM: UDP-arabinopyranosemutase; AXS: UDP-D-Xylose synthase; RHM: UDP-rhamnose synthase; INV: invertase; HK: hexokinase; PGM: phosphoglucomutase; FRK: fructokinase; MPI: mannose-6- phosphate isomerase; PMM: phosphomannose isomerase; GMPP: GDP-mannose pyrophosphorylase; GMD: GDP-D-mannose-4,6-dehydratase; GER1: GDP-4-keto-6-deoxy-D-mannose-3,5-epimerase-4-reductase; GT: glycosyltransferase.

    • Kinds Compounds Sources Effects Applications Ref.
      Alkaloids Tomatidine Solanum lycopersicum Antibacterial, anticancer, antiviral, anti-inflammatory and neuroprotective Foods, drugs [10]
      Piperine Piper nigrum Anticancer, antidepressant, anti-inflammatory, antioxidant, neuroprotective Food flavorings, drugs [11]
      Berberine Phellodendron Bark Antiproliferative, anti-inflammatory, antibacterial, antiviral Drugs [12]
      Caffeine Coffee, tea, chocolates Analgesic, anticancer, antioxidant, antibacterial Meals and beverages [13]
      Trigonelline
      		 Eggplant Anti-tumor, neuroprotective Foods, drugs [14]
      Betaine Wheat bran, wheat germ, spinach Anti-diabetic, anti-inflammatory, antioxidant Dietary supplement [15]
      Morphine Poppy heads Pain relief, sedation, euphoria, respiratory depression Agonists [16]
      Theobromine Cocoa tree Neuroprotective, anti-inflammatory Obesity treatment drugs or formulations [17]
      Terpenoids Carvacrol Origanum compactum
      		 Antimicrobial, antioxidant, anti-inflammatory Food preservative [18]
      Menthol Peppermint leaves Antibacterial, antifungal, antioxidant Additive, essential oils
      		 [19]
      Thymol Thymus pectinatus Antimicrobial, antioxidant
      		 Food flavorings, mouthwashes [20,21]
      Caryophyllene Piper nigrum Anti-inflammatory, antioxidant, anti-neurodegenerative The essential oils of spices and food plants
      		 [22]
      Nerolidol Citrus sinensis Antioxidant, anti-microbial, anti-biofilm, anti-parasitic, insecticidal Essential oils, flavor enhancer [23]
      Perillyl alcohol Cymbopogon caesius Anticancer, antimicrobial, antioxidant, anti-inflammatory Aroma, natural additives in food [24]
      Camphene Piper cernuum Anti-tumor, antioxidant Food flavorings, fragrances, plasticizers [25]
      Stevioside Stevia rebaudiana Anti-inflammatory, antioxidant Sweetener, immunomodulator [26]
      Patchouli alcohol Pogostemon cablin Anti-inflammatory, antioxidant, antitumor Medicine, flavouring and food industries, essential oils [9]
      Ginsenoside Panax ginseng Anti-inflammatory, antibacterial, immunity-improving Antibiotics, drugs [27]
      Corosolic acid Lagerstroemia speciosa Antioxidant, anti-inflammatory, antifungal, Medicines, health products [28]
      β-carotene Medicago sativa Anticancer, anti-disease Pigment [6]
      Lutein NuMex LotaLutein Antioxidant, photoprotective Dietary supplements, pigment [29]
      Capsanthin Capsicum annuum Antioxidant, anticancer Nutrients, pigment [30]
      Lycopene Amaranthus gangeticus Anti-inflammatory, antioxidant, anticancer Food additive, jelly [31]
      phenylpropanoids
      		 Eugenol Eugenia caryophyllata Antimicrobial, antifungal Food preservative and colorant
      		 [32]
      Umbelliferone Fruits, vegetables, and plants Antioxidant, anticancer Nutraceuticals, functional foods, drugs [33]
      Ferulic acid Sorghum straw
      		 Antioxidant, antiviral, anticancer Beer production [34]
      Chlorogenic acid Higher dicotyledonous plants and ferns Antibacterial, anti-inflammatory, antiviral, antioxidant Feed additive [7]
      Caffeic acid Plant-based lignocelluloses Antiviral, antioxidant, anti-inflammatory, anticarcinogenic Food, drugs [34]
      Vanillin Vanilla planifolia
      		 Antioxidant, anti-inflammatory, antimicrobial Sweetener, food additive [35]
      Rosmarinic acid Perilla frutescens
      		 Anti-inflammatory, antioxidant, antibacterial Food flavoring, and preservative [8]
      Polysaccharides Lentinan Lentinus edodes Antitumor, immune potentiating Food supplement, biological response modifier [36]
      Lycium barbarum polysaccharide Lycium barbarum Antioxidant, anti-fatigue, anti-diabetic, neuroprotection Food, medicine, dietary supplements [37]
      Ganoderma lucidum polysaccharide Ganoderma lucidum Antitumor, anti-inflammatory, immunomodulatory, antioxidant Functional foods, and pharmaceuticals [38]
      Longan polysaccharide Dimocarpus longan Antioxidant, anticancer, immunomodulatory, hypoglycemic, antibacterial Herbs, foods [39]
      Pumpkin polysaccharide Pumpkin Antidiabetic, antioxidant, anticancer, immunomodulation,antibacterial Foods, Chinese medicine [40]
      Tea polysaccharide Tea Antioxidant, anti-cancer, anti-inflammatory, immunomodulatory, Beverages [41]

      Table 1. 

      Sources of various common natural products in food and their functional applications.