Curcuma contains phenols curcuminoids, and particularly curcumin, and is thus active on several molecules involved in inflammatory phenomena, through the reduction of the pro-inflammatory eicosanoids synthesis. Curcuma extracts' effectiveness in playing antioxidant, antineoplastic, and liver protective functions is proven by a number of in vitro and animal studies and by a few human clinical trials (Di Silvestro, 2012; Darvesh, 2012; Kulkarni, 2010; Rajasekaran, 2011; Shehzad, 2011).

Since the first scientific studies, curcuma's limited bioavailability has been a major issue. After its oral administration, curcumin's concentration in blood lowers dramatically or even disappears. This low bioavailability is due to its low solubility in water, to its degradation into the gastro-intestinal tract, to the high velocity of the metabolism and to its rapid elimination. This is why we need to ingest a high- quantity of curcumin (12-20 g/die) to have a therapeutic effect. Curcuma does not have a negative interference with drugs, and does not cause adverse events, even in high dosage.

The critical point of using curcuma is not related to its quantity but it is related to its solubility, permeability and stability; hence to its bioavailability. Many approaches have been used to solve this problem: the use of piperine, synthetic analogues, the chelation with metals, the combination with other dietary agents. New nanotechnologies are also being developed by the scientific community.

Table Antioxidant Substances of Plant Origin.



P-caroten, lycopene


Lutein, zeaxanthin, astaxanthin, capsaxanthin, cryptoxanthin



Phenolic acids (caffeic acid), coumarins, benzoic acids, stilbenes (resveratrol)


Proanthocyanidins, ellagic acid


Flavonols, flavones, isoflavones, anthocyanins, catechins

The Journal of Nanobiotechnologies published lots of articles and reviews regarding curcumin encapsulated in different forms: polymers, nanoparticles, nanoemulsions, nanoliposomes, fitosomes (Indena's Meriva®, Verdure Sciences' Longvida®, Acquanova AG's NovaSOL®): in these forms the absorption of curcuminoids is highly increased (Ranjan, 2012; Savita, 2007; Ledda, 2012).

As shown on Table, compounds with an antioxidant activity are frequent among botanicals. An antioxidant has been defined as “any substance that, when present at low concentrations compared with those of an oxidizable substrate, significantly delays or prevents oxidation of that substrate” (Halliwell, 2004). Oxygen's reactive species can modify the structure of the membrane's cell or of the cell's genetic material and therefore they are considered the cause of aging and of different pathologies such as cardiovascular diseases, neoplasia, SNC's degenerating diseases.

Table reports a classification of antioxidant substances of plant origin.

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