Separation and purification of crocin using nano-graphene adsorbent andcolumn chromatography

Crocins, a group of polyandicarboxylic acid, crocetin mono- and diglucosylesters, are the main colors that make up saffron and gardenia compounds.Other plants such as Buddleja spp. also produce crocin, but due to their lowconcentration, they are not used commercially.Crocin is a chemical diester that consists of crocetin dicarboxylic acid andgentiubiose disaccharide. Crocins are glycosyl esters of crocetin, which areproduced by esterification of crocetin with various glycosides, includinggeometric isomers. The activity of glucosyltransferases causes the transfer ofcrocetin molecules, which add different amounts of glycosides to producecrocin, a major component of saffron that provides water solubility. Crocinsare responsible for many of the pharmacological effects of this valuable plant.Unlike other carotenoids, crocins have ۲۰ carbons and several glycosides.Several previous studies have shown that crocins, especially alpha-crocin, haveradical-quenching, antioxidant, and anti-inflammatory properties. [۱]Crocin (polyene mono- or diglycosyl esters) is a key bioactive component insaffron that dissolves easily in water and produces a distinctive red color,making saffron a natural coloring compound. It is recorded at ۴۴۰ nm. Crocinslose their functionality due to their limited stability exposed to light, heat, andacidic nature. Also, they have low absorption and bioavailability, because inthe case of oral consumption, they undergo hydrolysis to producedeglycosylated trans-crocetin in the intestinal tract with enzymatic conditioning in Intestinal epithelial cells and fecal bacteria are not absorbed. [۲]Crocin has several pharmacological effects, including anti-inflammatory and cancer cell growth inhibitory properties under various experimental settings. Crocin has also been shown to protect against oxidative damage to brain vessels, kidney tissues, heart and retina. [۳] In addition to antihypertensive, anti-platelet aggregation, nephron protective, anti-depressant and anti-atherosclerotic effects, these plant compounds destroy free radicals, especially against superoxide anions, with increasing age the possibility of neurological disorders such as epilepsy, Parkinson's and Alzheimer's. It is increasing that the risk of contracting these diseases can be reduced by consuming crocin and saffron.Studies have shown that the natural carotenoid molecule, crocin, offers therapeutic potential in the treatment of neurological disorders [۵].Crocin also increases dopamine in the brain during Parkinson's disease. As a result, this chemical has been shown to be a promising treatment option for neurological diseases. According to randomized, double-blind, placebo-controlled trials, medicinal levels of crocin do not harm the body. In a randomized, double-blind clinical trial, crocin (۲۰ mg/day) was found to be safe in healthy volunteers, with no significant changes in blood, hormonal, biochemical, or urinary markers. The aim of this review is to describe the role of crocin in functional food production, extract and critically evaluate previous and current findings on the biological/pharmacological actions of crocin against various brain-related diseases.[۶]