# Anti-Inflammatory and Antioxidant Effects Induced by
## 1 Introduction  
Garlic (_Allium sativum_ L.) is an herbaceous plant, belonging to the Amarillidaceae family, that is used all over the world as traditional medicine and spice [1]. Garlic contains a number of biologically active compounds, including phenolic compounds [2], saponins [3], polysaccharides [4], as well as organosulfur compounds [1] that contribute to its countless pharmacological properties. In particular, the health-promoting properties induced by garlic were suggested to be related to its bioactive compounds, including phenolic compounds,whose content in this plant is relatively high [5]. However, the content of phenolic compounds in garlic was reported to be dependent on environmental, genetic and agronomic factors [6]. Preclinical and clinical studies demonstrated the anti-inflammatory, antioxidant, antiatherosclerotic, anticancer, immunomodolatory, antidiabetic, antiobesity, neuroprotective, as well as digestive system protective activities of both garlic and its phenolic constituents [1]. Interestingly, raw garlic showed higher antioxidant activity compared to cooked garlic [7], suggesting that the antioxidant property of garlic could be modified by the processing methods. Moreover, in vitro and in vivo studies showed that garlic could suppress inflammation mainly through inhibition of various inflammatory biomarkers, including nitric oxide (NO), tumor necrosis factor (TNF)-\(\alpha\), and interleukin (IL)-1 [1].  
The beneficial effects induced by garlic were also be related to its organosulfur compounds, including diallyl thiosulfonate (allicin), diallyl sulfide (DAS), diallyl disulfide (DADS), diallyl trisulfide (DATS), E/Z-ajoene, S-allyl-cysteine (SAC), as well as S-allylys cysteine sulfoxide (allisin) [1]. In particular, allicin was reported to be among the most important bioactive constituents exerting antioxidant effects [8].  
Inflammatory bowel diseases (IBDs) are chronic and multifactorial inflammatory conditions of the colonic mucosa (ulcerative colitis), characterized by increased and unbalanced immune response to external stimuli [9; 10; 11]. In this context, antioxidant/anti-inflammatory herbal extracts were found to contrast IBD-related symptoms [12; 13] by reducing various pro-inflammatory and oxidative biomarkers, such as reactive oxygen/nitrogen (ROS/RNS) species, prostaglandandins, and cytokines.  
Interestingly, garlic was suggested to exert protective effects against ulcerative colitis [14]. In addition, garlic oil suppressed endotoxin-induced neutrophil infiltration in small intestine of rats [15]. Moreover, [PERSON] and collaborators (2016) [16] showed that garlic oil (GO) was able to inhibit ulcerative colitis induced by dextran sulfate sodium in rats. This effect was suggested to be related to antioxidant, anti-inflammatory as well as to immunomodolatory effects of GO. Accordingly, more recently, GO was reported to decrease inflammation and cellular damage in a rat model of colitis induced by acetic acid [17].  
On the basis of these findings, in this study, we aimed to evaluate the potential protective effects of a hydroalcoholic extract (GHE) and a water extract (GWE) of garlic on isolated mouse colon specimens treated ex vivo with _E. coli_ lipopolysaccharide-saccharide (LPS), which represents an experimental model of ulcerative colitis [18]. In particular, our research focused on hydroalcoholic and water extracts from a Sicilian variety of garlic (Nubia red garlic), known for the intense red color of the robes of its bulbis [19]. This variant is a protected denomination of origin product (DOP), which is appreciated all over the world. We reported here in, to the best of our knowledge, the first potential beneficial effects of Nubia red garlic on colon inflammation.