## 1 Introduction  
Phloroglucinol (PG) or 1,3,5-trihydroxybenzene is a natural phenolic compound found in certain plant species, bacteria and brown algae [1] and is used as an antispasmodic agent in commercial pharmaceutical formulations. It is available as a non-prescription medicine n the form of 80 mg tablets with therapeutic indication for scenarios of contractions of the intestine, bile ducts, urinary tracts and uterus [2]. The efficacy of phloroglucinol is particularly relevant in patients with irritable bowel syndrome (IBS), namely regarding its ability to reduce pain [3, 4], bloating and mucus production [3] as well as its regulating action on the passing of stool [3]. The antispasmodic action of phloroglucinol can also be useful in the prevention of miscariages in women with the threatened abortion condition (typically older women are at higher risk): phloroglucinol acts by inhibiting uterine contractions and is safer and more effective than other drugs, such as magnesium sulphate [5]. The phenolic nature of phloroglucinol makes it a powerful antioxidant. In vitro studies showed a ferric reducing ability of plasma value of 96 \(\upmu\)M eq. FeSO\({}_{4}\) as early as within 4 min of the assay, rising to 365 \(\upmu\)M eq. FeSO\({}_{4}\) after 30 min, and a radical scavenging ability, at a concentration of 250 \(\upmu\)M, of 443 \(\upmu\)M Trolox equivalents in the Trolox equivalent antioxidant capacity assay [6]. Moreover, this compound was demonstrated to effectively scavenge reactive oxygen species (ROS) in skin cells, protecting them from the damaging effect of UVB exposure [7]. In vivo studies involving the direct administration of phloroglucinol to rat brain showed that it protects midbrain dopaminergic neurons from the neurotoxin 6-hydroxopamine through direct ROS quenching and by up-regulating the expression of the antioxidant enzymes catalase and glutathione, thus, hinting at a possible anti-Parkinson effect [8]. Encapsulation of phloroglucinol can offer protection against premature oxidation and extend it for controlled release. Thus far, phloroglucinol encapsulation is reported only by cross-linking with starch with a strong reduction in the antioxidant activity because the hydroxyl groups involved in the cross-linking bonds becomes unavailable for radical scavenging [9]. In this work, we present an encapsulation strategy based solely on non-covalent bond interactions: the formation of supramolecular adducts with cyclodext. Formed by bacterial or enzymatic degradation of starch, cyclodext are natural cyclic oligosaccharides, typically occurring with six (\(\alpha\)-CD), seven (\(\beta\)-CD) or eight (\(\gamma\)-CD, Figure 1a) D-glucose units linked together by \(\alpha\)-1,4 glycosidic bonds. They present the shape of a truncated cone, with the secondary hydroxyl groups facing the wider rim, the primary hydroxyls at the narrower rim and the cavity lined with protons. Cyclodext are, thus, water soluble, and they can help solubilise other molecules that have an adequate size to fit in their cavity [10; 11]. Cyclodext can be further used as stabilising and taste-masking agents for a variety of drugs and cryopreservatives or co-adjuvants in vaccines [12; 13; 14; 15; 16; 17]. The properties of cyclodext make them also very useful in the formulation of food products, particularly those that have been fortified in order to have nutraceutical activity [18; 19]. Cyclodext have been intensively employed in helping formulate plant active compounds, such as flavonoids [20; 21; 22], carotenoids [23; 24], terpenoids [25] and a vast range of polyphenols [26; 27; 28; 29]. In food applications, the use of \(\gamma\)-CD is preferred over the other native cyclodext owing to its higher digestibility and the fact that it can be ingested without any dose limits. The formation of the inclusion compound \(\gamma\)-CD-PG and its effect on the radical scavenging activity of the guest, phloroglucinol, is herein presented.