Phytochemicals with a wide diversity in structure and bioactivity have long been sources for pharmaceu­tical agents ("phytomedicines", Pandey et al., 2011). One important bioactive group is carotenoids. Astaxan — thinhas uses as anticarcinogens, antioxidant, antiinflam­mation (da Fonseca et al., 2011), cholesterol effector, pain reliever (Skjanes et al., 2012) or immune system booster (Abad and Turon, 2012). Canthaxanthin also suits for antioxidant or antiinflammation uses (Skjanes et al., 2012). b-Carotene may serve to prevent erythema or arthritis (Skjanes et al., 2012).

Another major bioactive phytochemical group is iso — flavones, especially those from soybean. For instance, daidzein, genistein and glycitein are antioxidative or estrogenic, potentially beneficial in cancer, heart disease or obesity prevention.

Phytosterols or triterpenes are phytochemicals benefi­cial for cholesterol, cancer or immune system-related con­siderations. Saponins (saponenols glycosides) are also thought to be beneficial for certain cancer, heart, liver illness treatments (Wu and Kang, 2011; Guclu-Ustundag and Mazza, 2007; Zhao and Moghadasian, 2010). Organic sulfur compounds, such as allylsulfides, also have

anticancer potential (Cerella et al., 2011). Polyamine — hydroxycinnamic amide conjugates are antioxidative and antimelanogenic (Choi et al., 2007). Lignans are also antioxidants; so are phytic and cinnamic acid ester glycosides (Wu and Kang, 2011; Guclu-Ustundag and Mazza, 2007). Menthol and essential oils are used as topical analgesic or antiitching agents, decongestants or oral hygiene ingredients. Capsaicin also has topical uses for relieving pain, itch or inflammation.

Highly effective, pharmacologically well-studied med­icines originated from plants include quinine, ephedrine, artemisinin, paclitaxel (Taxol) and vinblastine, galanth — amine and digoxin, as well as opiates like morphine and cocaine. Plant-derived precursors for medicines include 10-deacetylbaccatin (for paclitaxel), (—)-shikimic
acid (for oseltamivir phosphate or Tamiflu), diosgenin (for various steroid hormones), salicylic acid or salicin (for acetylsalicylic acid or aspirin) (Pandey et al., 2011).

There are also phytochemicals that can be used for agriculture or forestry protection (‘agrochemicals’, Huter, 2011; Dayan et al., 2009). For example, leptosper — monefromCalHstemoncitrinusplant is used as herbicide (Salim et al., 2008); lemongrass oil as pesticide or herbi­cide; essential oils (e. g.D-limonene), pyrethrum, nicotine and rotenone as insecticide; thymol and pyrolyzed to­bacco bio-oil as biocide (O’Brien et al., 2009; Dayan et al., 2009); and corn gluten meal and essential oils for weed control.

The structures of many bioactive phytochemicals are shown in Figure 20.4.

Phytochemicals for Personal Care or Other Uses

Various phytochemicals are used for personal care because of their performance and renewability. Betaine (trimethylglycine ammonium salt) has significant poten­tial for hair care (Kripp, 2006), lutein and b-carotene as colorant, and menthol and citronella oil for insect repelling.

There are other industrial uses of phytochemicals. Lecithin is useful for antifoaming, dispersion, stabiliza­tion, or wetting. Tannin is used for leather processing (tannery), wood products (e. g. particle board) adhesion (Frihart, 2010), or anticorrosion. Lignin may be used for making resins.