Potential Therapeutic Applications of Some Antinutritional Plant Secondary Metabolites

Abstract

Plant-based formulations have been used since ancient times as remedial measures against various human and animal ailments. Over the past 20 years interest in traditional medicines has increased considerably in many parts of the world. Whereas modifications in lifestyles, including diet, have had a profound effect on the increased risks of various diseases, there is considerable scientific evidence, both epidemiological and experimental, regarding vegetables and fruits as key features of diets associated with reduced risks of diseases such as cancers and infections. This has led to the use of a number of phytometabolites as anticarcinogenic and cardioprotective agents, promoting a dramatic increase in their consumption as dietary supplements. There are changing perceptions regarding the therapeutic potential of various plant secondary metabolites (PSMs), some of which have also been known to possess certain antinutritional qualities. The knowledge gained at the cellular and molecular levels, and biological activities of PSMs including tannin-polyphenols, saponins, mimosine, flavonoids, terpenoids, and phytates, would be useful in planning for future epidemiological studies and human cancer prevention trials, especially when a large pure dosage is not the option to deliver the active compounds to many tissues. It is well observed that alteration of cell cycle regulatory gene expression is frequently found in tumor tissues or cancer cell lines, and studies have suggested that the herbal-based or plant-originated cell cycle regulators might represent a new set of potential targets for anticancer drugs. The recent upsurge of interest in this area of research and advances made therein indicate that the impact of a number of diseases affecting humans and animals may be lessened, if not prevented, by simple dietary intake of PSMs with putative therapeutic properties.

Bioactivity of phytochemicals in some lesser-known plants and their effects and potential applications in livestock and aquaculture production systems

“…Subclinical infections of gastrointestinal nematodes such as Ostertagia circumcinta, Trichostrongylus colubriformis and Haemonchus contortus decrease feed intake, body-weight gain, and milk and wool production. In subtropical and tropical areas of the world where the animals are on low quality feeds and have poor nutritional status, mortality and morbidity due to nematode infection are widespread (Singh et al, 2003). There is a growing realisation that chemical anthelmintic treatment, on its own, may not provide a longterm strategy for managing parasites in grazing animals.…”

“…In the past decade, many reports have emerged showing anthelmintic effects of tannins/polyphenols and the benefits they could provide to livestock by decreasing nematode load in extensive grazing production systems (Singh et al, 2003). These effects on nematodes are attributed to an improved protein supply due to increased rumen undegradable protein and their availability post-rumen and also to the direct action of tannins against nematodes.…”

“…Several beneficial effects of phytate including cancer prevention, reduction in iron-induced oxidative injury and reversal of initiation of colorectal tumorigenesis, and prevention of lipid peroxidation have been reported (Singh et al, 2003).…”

Natural alternatives to in-feed antibiotics in pig production: can immunomodulators play a role?

“…It has been suggested that these 'weak immune modulations' may be due to the low purity of the extract used (Ilsley et al, 2005), which could reach a maximal level of 10% of saponins. Moreover, tannins, which could be as high as 15% in a crude extract of Q. saponaria, might have induced a detrimental response, as they are known to have anti-nutritional properties (Singh et al, 2003). Thus, Ilsley et al (2005) incorporated a saponin extract from Q. saponaria in the diet, alone or in combination with curcumin, which has been shown to modulate lymphocyte-mediated immune functions in mice (Churchill et al, 2000).…”

Isolation, Identification and Molecular Characterization of Tannase Producing Klebsiella sp., from the Rumen of Migratory Goats and Sheep

“…Tannins are the one of the most abundant plant polyphenolics distributed widely among vascular plants as well as in pteridophytes, angiosperms and gymnosperms (Singh et al, 2003;Mueller-Harvey, 2006). Tannins being capable of forming reversible and irreversible complexes with proteins, often limits the use of nutritionally important forage trees, shrubs, legumes etc., as feeds for livestocks (Chavez-Gonzalez et al, 2012).…”