ABSTRACT
Background: Agriculture products, especially medical plants after harvest should be processed by different processes such as removal of foreign bodies, washing and cleaning, drying, packaging and so forth. One of main postharvest stages of medical plant especially peppermint is drying process
Objective: The aim of this study is design a solar dryer equipped with double pass collector to drying process of peppermint and comparison their results with traditional drying methods [sun and shade]
Methods: In this study drying process of peppermint with different methods of solar drying [by solar dryer designed in this study] and also traditional drying [shade and sun drying] were investigated and compared
Results: The drying time required for dehydration of peppermint in solar drying method was 150 min, which it was approximately 82% and 55% shorter than to traditional methods of shade and sun. Furthermore, dehydration rate in drying methods of solar drying, sun drying and shade drying were 26.77, 12.48 and 4.48 [kg H2O/kg D.M h], respectively. The results of mathematical modelling indicated that Midli and kucuk [in drying methods of solar and shade] and Aghbashlo et al [in drying method of sun] can be fitted drying curve of this medical plant with high accuracy. Also, solar drying by dryer could be protecting the essential oil of this plant in the best form. The results show that the main components of peppermint essential oil was included: 1,8-Cineole, cisSabinene hydrate, Menthone, Menthofuran, iso-Menthone, Menthol and iso-Menthol
Conclusion: Generally, solar drying method of peppermint was recommended as the best method for postharvest processing of this medical plant
ABSTRACT
Stigmas of Crocus sativus L. [Iridaceae], commonly known as saffron, is the world's most expensive spice and apart from its traditional value as food additive recent studies indicate its potential as antidepressant. Because saffron is expensive, using it daily to address depression may not be practical. Moreover, recent study indicated antidepressant effect of petal of Crocus sativus. As petal of Crocus sativus is not expensive compared to stigma, there will be economical interests for further investigations by pharmaceutical industries. Our objective was to compare the efficacy of petal of Crocus sativus with stigma of Crocus sativus in the treatment of depressed outpatients in a 6-week pilot double-blind randomized trial. Forty four adult outpatients who met the DSM- IV criteria for major depression based on the structured clinical interview for DSM- IV participated in the trial. Patients have a baseline Hamilton Rating Scale for Depression score of at least 18. In this double-blind and randomized trial, patients were randomly assigned to receive capsule of petal of Crocus sativus 15 mg bid [morning and evening] [Group 1] and capsule of stigma of Crocus sativus 15 mg bid [morning and evening] [Group 2] for a 6-week study. At the end of trial, petal of Crocus sativus was found to be effective similar to stigma of Crocus sativus in the treatment of mild to moderate depression [d.f.=1, F= 0.05, P=0.81]. In addition, in the both treatments, the remission rate was 18%.There were no significant differences in the two groups in terms of observed side effects. The present study is supportive of other studies which show antidepressant effect of petal and stigma of Crocus sativus