## 4 Discussion
### Antioxidant and Anti-Inflammatory Pathways Targeted by Phytochemicals for the Treatment of IBD
It enhances defensive factors of the mucosa such as NO systems, prostaglandamdins like PGE2 and the mucin pathway whose depletion is related to UC pathogenesis [134; 135; 136; 137]. Herbal preparations used as IBD complementary or alternative therapies are being utilized more often. An interesting example can be made out of the herbal combination of myrrh, chamomile flowers and coffee charcoal, which has been used for 50 years as a simple remedy for diarrhea. After considering the individual constituents and their known and validated effects from animal and experimental studies, it was concluded that the herbal preparation ought to target multiple pathways. Furanosesquiterpene, commiporic, commiphorinic acids and volatile oils contained in myrrh resin have demonstrated anti-inflammatory and antibacterial effects in animal studies. Inhibition of leukotriene production is hypothesized as the substrate. Chamomile tea or dry extract contain flavonoids, hydroxycumarines and many other phytochemicals which are known for their anti-inflammatory, spasmolytic and antimicrobial properties. Finally, coffee charcoal is used for its antibacterial and absorbing properties. After confirmation of the preparation's beneficial effect, further clarification of individual phytochemical bioactive substances and development can be undertaken [32]. Cannabis consists of many phytochemicals like alkaloids, glycoproteins, terpenoids, flavanoids and cannabinoids. Among them, cannabidiol, tetrahydrocannabinol and cannabigerol are the most investigated bioactive substances for various diseases [138; 139]. Cannabidiol and tetrahydrocannabinol interact with the endocannabinoid system to produce their effects. Cannabinoid receptor 1 (CB1) and 2 (CB2) are found in the brain but also in the submucosal and myenteric nerve plexus of the intestine, with the latter also appearing in immune system cells [140]. Cannabinoids also target various other receptors in a complex process that must be further clarified. Endogenous and phytochemical cannabinoids acting as CB2 agonists or fatty acid amide hydrolase inhibitors display reduced inflammation in colitis animal models as demonstrated by recent studies [141]. CB2 also appears to be upregulated in UC patients [142]. Inulin-type fructans or FOS have been suggested to be effective in human IBD as prebiotics, ultimately enhancing the gut microbiota by stimulating the growth in protective bifidobacteria and _F. prausnitzii_ populations. They are non-digestible polymers of fructose that in animal models of colitis decreased disease activity and decreased NF-kB. In addition, fermentation of such prebiotics produces SCFAs that enhance intestinal epithelial barrier integrity. Furthermore, in combination with FOS, bacteria such as _B. longum_ taken from healthy subjects appear to have a clinical benefit [143,144]. Curcumin is a bioactive phytochemical compound isolated from the well-known plant turmeric (_Curcuma longa_). It has been used as a food additive or spice with antioxidant, anti-inflammatory and antineoplastic properties [145, 146, 147]. In vitro experimental studies on human colon cell lines provide evidence that curcumin inhibits carcinogenesis and inflammation through reduction of NF-kB, cytokines and cyclooxygenase-2 activation [148]. Similar findings have been found in animal model studies [149,150].