Defense phytochemical

Think of an aril the way Mother Nature made it it is a protective layer of water, trace nutrients, and defensive phytochemicals called puni-calagins (a group of ellagitannin compounds thought to be strong antioxidants) contained in a barely noticeable sheath covering the seed. 

A second class of defensive phytochemicals often found in poplar and aspen at substantial levels are the proanthocyanidins, or condensed tannins (CTs) (Fig. 5.1). Unlike the phenolic glycosides that are found exclusively in the Salicaceae, CTs are widespread in the plant kingdom. These flavonoid polymers consist of mostly 4,8-linked flavan-3,4-diols and flavan-3-ols, ranging in size from 1440 to over 4500 Da depending on the species. Flavonoids are derived from the general phenylpropanoid pathway by a series of enzymes beginning with the enzyme... 

A wide diversity of herbal remedies have purported abilities to stimulate defense functions. Complexes of carbohydrate and lignin, which are present in some herbs, modulate enteric immune functions (Kiyohara et al, 2000), and the changes in cytokine secretion (Matsumoto and Yamada, 2000) can trigger systemic responses. The polysaccharides present in other herbal medicines augment production of immunoglobulin (Ig) A by the Peyer s patches in the small intestine (Sakushima et al, 1997 Yu et al, 1998). The responses of the enteric immune system to lectins are variable (Pusztai 1993), and can elicit systemic responses (Lavelle et al, 2000). Other phytochemicals provide protection by inducing detoxification pathways in mucosal cells (Williamson et al, 1998). 

Proteinaceous phytochemicals can contain toxic epitopes that elicit defense responses for example gliaden and glutein peptides which cause celiac disease and other mucosal disorders (Tighe and Ciclitira, 1995 Van de Wal et al, 1999). The mucosal inflammation caused by feeding carnivorous Atlantic salmon diets with soybean meal decreases rates of nutrient absorption (Nordrum et al, 2000), whereas the detrimental influence of such diets is much less pronounced when fed to omnivorous fish, such as catfish and tilapia. 

Many phytochemicals are regarded as protective food components because of their defensive potential against damaging reactive oxygen species within the human body. 

UV-C technology is widely used as an alternative to chemical sterilization and microorganism reduction in food products (Lamikanra 2002 Fan and others 2008). Ultraviolet light also induces biological stress in plants and defense mechanisms in plant tissues with the consequent production of phytochemical compounds (Lee and Kader 2000). Phytoalexin accumulation could be accompanied by other inducible defenses such as cell-wall modifications, defense enzymes, and antioxidant activity, which have been reported with health benefits (Gonzalez-Aguilar and others 2007). It is well documented that UV-C irradiation has an effect in secondary metabolism. 

Volume 33 Phytochemicals in Human Health Protection, Nutrition, and Plant Defense Proceedings of the Thirty-eighth Annual Meeting of the Phytochemical Society of North America, Pullman, Washington, July, 1998... 

Koivikko R, Loponen J, Pihlaja K, Jormalainen V (2007) High-performance liquid chromatographic analysis of phlorotannins from the brown alga Fucus vesiculosus. Phytochem Anal 18 326-332 Koricheva J (2002a) Meta-analysis of sources of variation in fitness costs of plant antiherbivore defenses. Ecology 83 176-190... 

Feeny PP (1976) Plant apparency and chemical defense. Res Adv Phytochem 10 1—40 Fraenkel GS (1959) The raison d etre of secondary plant substances. Science 129 1466-1470 Franklin LA, Yakovleva I, Karsten U, Liming K (1999) Synthesis of mycosporine-like amino acids in Chondrus crispus (Florideophyceae) and the consequences for sensitivity to ultraviolet B radiation. J Phycol 35 682-693... 

Cornell HV, Hawkins BA (2003) Herbivore responses to plant secondary compounds a test of phytochemical coevolution theory. Am Nat 161 507-522 Cronin G (2001) Resource allocation in seaweeds and marine invertebrates chemical defense patterns in relation to defense theories. In McClintock JB, Baker BJ (eds) Mar Chem Ecol. CRC, Boca Raton, FL, pp 325-354... 

Phytochemical diversity of insect defenses in tropical and temperate plant families... 

There is a huge variety of plant defensive secondary metabolites that has been the subject of major phytochemical [1-6] or pharmacological and toxicological [7-12] compilations. This structural complexity is very briefly reviewed below before considering those plant bioactives with signal transduction targets. The major groups are the phenolics, the terpenoids and the alkaloids as well as bioactives structurally related to... 

Feeny, P., Plant apparency and chemical defense, Recent Adv. Phytochem., 10, 1, 1976. 

Volume 33 Phytochemicals in Human Health Protection, Nutrition, and Plant Defense... 

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