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Geotrichum citri‐aurantii causes sour rot in citrus fruits and is responsible for important economic losses during storage. However, the availability of chemical fungicides for the control of this pathogen is limited. Thus, the aim of this research was to evaluate the antifungal efficacy of thymol and carvacrol encapsulated in 2‐hydroxylpropyl‐beta‐cyclodextrin (HP‐β‐CD) (prepared by the microwave irradiation method [MW] and solubility method [S]) for inhibition of G. citri‐aurantii using in vitro bioassays broth (micro and macrodilutions methods) and inoculated food testing. Both encapsulated thymol and carvacrol were shown to be effective for inhibiting G. citri‐aurantii growth in in vitro assays. Thymol was more effective in inhibiting G. citri‐aurantii, while better encapsulation was provided by MW. HP‐β‐CD‐thymol encapsulated by MW (HP‐β‐CD‐thymol‐MW) showed the lowest 50% effective dose (ED50 = 1.16 mM), minimum inhibitory concentration (MIC = 5.06 mM), and minimum fungicide concentration (MFC = 52.6 mM). HP‐β‐CD‐thymol‐MW was found highly effective in reducing the growth rate and mycelial growth inhibition. Finally, HP‐β‐CD‐thymol‐MW and HP‐β‐CD‐carvacrol‐MW showed a higher persistent effect than thymol and carvacrol in their natural form in inhibiting this fungus. Therefore, HP‐β‐CD‐thymol‐MW could be a promising alternative to synthetic fungicides for controlling G. citri‐aurantii, the causal agent of citrus sour rot. Practical Application: Encapsulated thymol and carvacrol in HP‐β‐Cyclodextrins are effective for controlling G. citri‐aurantii in in vitro experiments. Encapsulation of thymol and carvacrol by microwave irradiation method (MW) was more effective than the solubility (S) method. Thymol was more effective than carvacrol, and the best results on G. citri‐auriantii inhibition were achieved using the HP‐β‐CD‐thymol‐MW method (which gave the lowest ED50, MIC, and MFC). [ABSTRACT FROM AUTHOR]

BACKGROUND Clove oil ( CO) is an aromatic oily liquid used in the food, cosmetics and pharmaceutical industries for its functional properties. However, its disadvantages of pungent taste, volatility, light sensitivity and poor water solubility can be solved by applying microencapsulation or complexation techniques. RESULTS Essential CO was successfully solubilized in aqueous solution by forming inclusion complexes with β-cyclodextrins (β- CDs). Moreover, phase solubility studies demonstrated that essential CO also forms insoluble complexes with β- CDs. Based on these results, essential CO-β- CD solid complexes were prepared by the novel approach of microwave irradiation ( MWI), followed by three different drying methods: vacuum oven drying ( VO), freeze-drying ( FD) or spray-drying ( SD). FD was the best option for drying the CO-β- CD solid complexes, followed by VO and SD. CONCLUSION MWI can be used efficiently to prepare essential CO-β- CD complexes with good yield on an industrial scale. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Consumers demand the use of eco-friendly fungicides to treat fruit and vegetables and governmental authorities have unauthorized the application of chemical antifungals for the efficient control of sour rot. In the present research, the microwave irradiation (MW) method was used to encapsulate thymol into 2-hydroxylpropyl-beta-cyclodextrin (HP-β-CD) and the effect of these HP-β-CD on controlling sour rot in citrus fruit, caused by Geotrichum citri-aurantii, was evaluated. Amounts of 25 and 50 mM of HP-β-CD-thymol were used, and compared with propiconazole, to control the decay of inoculated lemon fruit. The treatments were performed in curative and preventive experiments. The incidence and severity of Geotrichum citri-aurantii in 25 and 50 mM HP-β-CD-thymol-treated fruit were reduced in both experiments. The preventive 50 mM HP-β-CD-thymol treatment showed the best effect, reducing the sour rot, respiration rate and fruit weight loss during storage at 20 °C. HP-β-CD-thymol increased polyphenol concentration and the activity of antioxidant enzymes, such as catalase (CAT), ascorbate peroxidase (APX) and peroxidase (POD) in lemon peel, and the highest effects were found with the 50-mM dose. In conclusion, the results show that the use of thymol encapsulated by MW into HP-β-CD could be an effective and sustainable tool, a substitute to the synthetic fungicides, for G. citri-auriantii control in citrus fruit. [ABSTRACT FROM AUTHOR]

The capacity of cyclodextrins (CDs) to extract phenolic compounds from grape pomace was evaluated and compared with that of ethanol/water or aqueous extraction. The extraction method (stirring and ultrasound), temperature and time were also studied. Total phenolic compounds (TPC) and antioxidant activity were measured, and HPLC analysis was used to identify the phenolic compounds. The extracts obtained using the ethanol/water mixture presented the highest TPC content and antioxidant activity, followed by those obtained using CD solutions. The addition of CDs to the extractant agent had a selective effect on the extraction of catechin and epicatechin. The yield of catechin and epicatechin by using aqueous solutions of CDs was similar to that obtained using organic solvents as ethanol. [ABSTRACT FROM AUTHOR]