Curcumin is a light yellow ingredient isolated from the plant Curcuma longa L. which belongs to the family Zingiberaceae and originates from South Asia. In Asia it has been used since ancient times in traditional pharmaceutical methods while today, it is used not only in the pharmaceutical but also in the food and cosmetics industries (Meo, Margarucci, Galderisi, & Crispi, 2019; Vollono et al., N.d.). In essence, curcumin is the most representative polyphenol isolated from plant rhizomes with the first isolation taking place in 1815 (Giordano & Tommonaro, 2019).
Various biological properties have been attributed to this substance. Antioxidant activity, anti-inflammatory and anti-angiogenesis in certain organs and tissues such as adipose tissue, or for example inhibits the growth of blood vessels needed in areas for different tumors to grow (Zhao et al., 2017). In addition, immunomodulatory properties, antimicrobial, antischemic, anticancer, renal and hepatoprotective hypoglycemic and antirheumatic (Mirzaei et al., 2017). Many more articles analyze the beneficial properties of curcumin in skin and neurodegenerative disorders (Giordano & Tommonaro, 2019; Vollono et al., N.d.).
At this point it is necessary to emphasize that curcumin is a non-toxic ingredient and the human body can tolerate high amounts without particular side effects. (Meo et al., 2019). This fact has also been recognized by the Food and Drug Administration (FDA). It is reported that the maximum daily consumption ranges from 3mg / Kg up to 4-10gr and in some cases e.g. disease high doses can lead to mild symptoms such as nausea and headache (Vollono et al., n.d.). Some articles list specific amounts of curcumin in relation to specific health conditions. For example, curcumin has been reported to be effective as an antioxidant and in inhibiting neurodegenerative disorders when administered at 50-200 mg / Kg / day (Meo et al., 2019)
However, all these therapeutic properties are significantly reduced due to the low bioavailability of curcumin in the body, especially after oral administration. Water solubility is low, it is chemically unstable and with rapid metabolism (Meo et al., 2019). In terms of rapid metabolism, it is achieved through glucuronidation and sulfation with final production --> metabolites that have significantly less biological activity than curcumin and are eliminated very quickly (Vollono et al., N.d.). After an experimental procedure in rats, where they were given 1g / kg oral curcumin it was found that 60-75% of this amount was excreted from the body through feces and partly through urine (Mirzaei et al., 2017; Vollono et al. , nd). The low bioavailability of this substance makes it difficult to accurately translate its potential therapeutic properties from in vitro findings to in vivo clinical cases (Mirzaei et al., 2017).
(Meo et al., 2019).
Therefore, efforts and researches are made to solve the aforementioned problem. Efforts include the use of nanoparticles, liposomes, adjuvants, mycelial and phospholipid complexes, and phytosome technology (Mirzaei et al., 2017; Tomeh, Hadianamrei, & Zhao, 2019).
Nanoparticles increase water dispersion, therefore, they focus on the problem of reduced water solubility. An experimental procedure in mice showed that this type of curcumin was much more effective in delaying diabetes-induced cataract than unformed curcumin after oral administration. Another method is considered to be the use of liposomes, which can help the absorption of both hydrophobic and hydrophilic substances and in the case of curcumin also enhance chemical stability. Such modification to curcumin can be used for intravenous administration (Mirzaei et al., 2017). Ranzal et al., In an article by Mirzaei et al., In 2017, point out that liposomal curcumin slowed the growth of pancreatic tumor in a human graft model. Also, adjuvants and auxiliaries can inhibit metabolic pathways responsible for inactivating or excreting curcumin from the body. The most well-known substance that enhances the bioavailability of curcumin is piperine, which acts by inhibiting liver and intestinal glucuronidation enzymes resulting in improved intestinal absorption of curcumin (Tomeh et al., 2019). As for the mycelial and phospholipid complexes, they seem to have the property of enhancing the intestinal absorption of curcumin from 47% to 56%. Finally, when we talk about phytosome technology, we mean the method of coupling phytochemicals, such as curcumin, to phospholipids, such as phosphatidylcholine, resulting in the formation of complexes with greater bioavailability to the body. It should be noted that the above methods are not used exclusively for curcumin but also for many other substances in the pharmaceutical industry (Mirzaei et al., 2017)
(Vollono et al., n.d.)
Another perspective that will be analyzed in the present study concerns the intestinal microflora. Many studies claim that polyphenols, such as curcumin, exert their properties after chemical modifications made by enzymes of the intestinal microflora. This results in catabolic products that are likely to be easily absorbed by the body. Therefore, the composition of the intestinal microflora will accordingly affect the biotransformation of dietary curcumin, thus, different beneficial properties of curcumin may occur in different individuals, due to the different composition in the intestinal microflora. Some of the bacteria that can catalyze curcumin are Escherichia coli, Blautia sp., Bifidobacteria longum, Bifidobacteria pseudocatenulaum, Lactobacillus acidophilus, Lactobacillus casei and others. After the action of enzymes from the bacteria, products such as dimethylcurcumin, dihydrocurcumin, tetrahydrocurcumin etc. can be obtained. where some may possess improved activity in some areas compared to curcumin (Meo et al., 2019).
But what effect does curcumin itself have on the intestinal microflora? It is supported and confirmed after research that curcumin modifies the ratio between beneficial and pathogenic bacteria in the intestine, favoring the development of beneficial versus pathogens. Therefore, there is an increase in Bifidobacteria, Lactobacilli and a decrease in Prevotellaceae, Coriobacterales, Enterobacteria and Enterococci. In addition, curcumin reduces the diversity of bacteria in the gut, by reducing specific species found to be associated with cancer (Meo et al., 2019).
(Meo et al., 2019).
References
Giordano, A., & Tommonaro, G. (2019). Curcumin and Cancer, (Table 1).
Lone, J., Choi, J. H., Kim, S. W., & Yun, J. W. (2016). ScienceDirect Curcumin induces brown fat-like phenotype in 3T3-L1 and primary white adipocytes, 27, 193–202. https://doi.org/10.1016/j.jnutbio.2015.09.006
Meo, F. Di, Margarucci, S., Galderisi, U., & Crispi, S. (2019). Curcumin , Gut Microbiota , and Neuroprotection, 1–14. https://doi.org/10.3390/nu11102426
Mirzaei, H., Shakeri, A., Rashidi, B., Jalili, A., Banikazemi, Z., & Sahebkar, A. (2017). ScienceDirect Phytosomal curcumin : A review of pharmacokinetic , experimental and clinical studies. Biomedicine et Pharmacotherapy, 85, 102–112. https://doi.org/10.1016/j.biopha.2016.11.098
Miyazawa, T., Nakagawa, K., Kim, S. H., Thomas, M. J., Paul, L., Zingg, J., … Azzi, A. (2018). Curcumin and piperine supplementation of obese mice under caloric restriction modulates body fat and interleukin-1 β, 1–9.
Tomeh, M. A., Hadianamrei, R., & Zhao, X. (2019). A Review of Curcumin and Its Derivatives as Anticancer Agents. https://doi.org/10.3390/ijms20051033
Vollono, L., Falconi, M., Gaziano, R., Iacovelli, F., Dika, E., Terracciano, C., … Campione, E. (n.d.). Potential of Curcumin in Skin Disorders, (Figure 1).
Zhao, Y., Chen, B., Shen, J., Wan, L., Zhu, Y., Yi, T., & Xiao, Z. (2017). Review Article The Beneficial Effects of Quercetin , Curcumin , and Resveratrol in Obesity, 2017. https://doi.org/10.1155/2017/1459497