Table 2.

Major classes of natural bioactive compounds, structure, main sources, and their therapeutic targets for wound-healing activity.

Bioactive Compounds—Major Classes			Example Compounds	Structure	Main Natural Source	Wound Healing Activity	References
Terpenes/Terpenoids	Monoterpenes		Borneol		Citrus peel oils (orange, lemon, lime), cinnamon leaf, cassia leaf, ginger, coriander seed, laurel, Ocimumbasillum, Thymus vulgaris, and Curcuma.	Anti-inflammatory, antioxidant activity with radical scavenging properties, antibiotic activity, antifungal, and wound-healing activity.	[147,148,149,150,151,152,153]
			Thymol		Essential oils of thyme, oregano, and carum.	Anti-inflammatory effect in human neutrophils and antioxidant activity. It exhibits antimicrobial activity and wound-healing activity.	[154,155,156,157,158,159,160,161,162,163]
			α-terpineol		Essential oils of pine and petitgrain.	Anti-inflammatory, wound healing effect and down-regulation of pro-inflammatory cytokines, reduction of NO production, antimicrobial activity, and antifungal effects.	[164,165,166,167,168]
			D-Limonele		Citrus essential oils.	Antioxidant, anti-inflammatory activities and neo-vascularization induction.	[169,170,171]
	Tetraterpenes (Carotenoids)	Carotenes	β-carotene		Carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantaloupe, winter squash, marine animals, and microalgae.	Antioxidant activity, metalloproteinases inhibition, cell proliferation, migration and angiogenesis stimulation and inflammation control.	[172,173,174]
			Lycopene		Tomato, watermelon, red carrots, pink grapefruit, pink guava, and papaya.	Antioxidant and anti-inflammatory activity and antimicrobial efficacy	[175,176,177,178]
		Xanthopylls	Astaxanthin		Algae, yeast, salmon, trout, krill, shrimp, and crayfish.	Strong anti-inflammatory and antioxidant activity. It regulates collagen through inhibition of MMP-1 and production of collagen, promotes keratinocytes migration and angiogenesis and accelerates wound-healing.	[179,180,181,182,183,184]
			Lutein		Microalgae, spinach, broccoli, lettuce, swiss chard, kale, parsley, pistachios, green peas, egg yolks, sweet corn, and red grapes.	Anti-oxidants and anti-Inflammatories	[185,186,187,188,189,190]
			Zeaxanthin
Alkaloids	Isoquinoline		Berberine		Goldenseal, barberry, Oregon grape, and tree turmeric.	Accelerate wound healing and enhanced ECM synthesis and inhibit oxidative stress and apoptosis, promote cell proliferation, down-regulation of MMP-9 and up-regulation of TGF-β1 and TIMP-1.	[191,192,193,194,195,196]
			Palmatine		Phellodendron amurense, Rhizoma coptidis/Coptis Chinensis, and Corydalis yanhusuo.	Antibacterial activity, antioxidant property, anti-inflammatory effect, accelerate wound healing and inhibit hypertrophic scar formation	[197,198,199,200,201,202]
Vitamins	Water-soluble		Ascorbic acid (Vitamin C)		Blackcurrant, strawberry, lemon, orange, lime, broccoli, Brussels sprouts, cauliflower, and cabbage.	Antioxidant, contributes to neutrophils functions and towards synthesis, maturation, secretion and degradation of collagen	[203,204]
	Lipid-soluble		α-tocopherol (Vitamin E)		Soybean, olive sunflower, and almond oils. It is also found in peanuts, asparagus, tomatoes, carrots, and some animal fats.	Major free radical scavenging antioxidant, anti-inflammatory and platelet aggregation inhibitor	[205,206,207,208,209,210,211,212,213,214,215,216,217,218]