Comprehensive chemotaxonomic analysis of saffron crocus tepal and stamen samples, as raw materials with potential antidepressant activity.

Saffron crocus (Crocus sativus L.) has been widely grown in Iran. Its stigma is considered as the most valuable spice for which several pharmacological activities have been reported in preclinical and clinical studies, the antidepressant effect being the most thoroughly studied and confirmed. This plant part contains several characteristic secondary metabolites, including the carotenoids crocetin and crocin, and the monoterpenoid glucoside picrocrocin, and safranal. Since only the stigma is utilized industrially, huge amount of saffron crocus by-product remains unused. Recently, the number of papers dealing with the chemical and pharmacological analysis of saffron is increasing; however, there are no systematic studies on the chemical variability of the major by-products. In the present study, we harvested saffron crocus flowers from 40 different locations of Iran. The tepals and stamens were separated and subjected to qualitative and quantitative analysis by HPLC-DAD. The presence and amount of seven marker compounds, including crocin, crocetin, picrocrocin, safranal, kaempferol-3-O-sophoroside, kaempferol-3-O-glucoside, and quercetin-3-O-sophoroside were determined. The analytical method was validated for filter compatibility, stability, suitability, accuracy, precision, intermediate precision, and repeatability. Tepal and stamen samples contained three flavonol glycosides. The main constituent of the tepals was kaempferol-3-O-sophoroside (62.19-99.48 mg/g). In the stamen, the amount of flavonoids was lower than in the tepal. The amount of kaempferol-3-O-glucoside, as the most abundant compound, ranged between 1.72-7.44 mg/g. Crocin, crocetin, picrocrocin, and safranal were not detected in any of the analysed samples. Our results point out that saffron crocus by-products, particularly tepals might be considered as rich sources of flavonol glucosides. The data presented here can be useful in setting quality standards for plant parts of C. sativus that are currently considered as by-products of saffron production.

Total anthocyanin, flavonoid, polyphenol and tannin contents of seven pomegranate cultivars grown in Iran.

BACKGROUND: Pomegranates are healthy fruits rich in bioactive phytochemicals and widely consumed in  the human diet. This study was designed to assess their physico-chemical properties and total polyphenolic compounds, along with antioxidant and ascorbic acid concentrations of the skin and juice of seven unstudied pomegranate cultivars grown in Iran. METHODS: Ten fruits of each of seven selected cultivars were picked. Methanolic extracts from the fruit skins as well as juices were subjected to an evaluation of their physico-chemical properties and phenolic content. RESULTS: From the pomegranate cultivars studied, the highest juice concentration was measured in ‘Zagh- -e-Zabol’ (72.9 ±2.55%). The highest total soluble solids (18.79 ±1.06 oBrix) of juice, as well as the highest ascorbic acid (16.54 ±2.09 mg/100 g) and total anthocyanin content of skin [11.20 ±2.4 mg CyE (cyanidin- -3-glucoside equivalent)/L] were measured in ‘Bajestan’. Total flavonoids were more concentrated in the skin of ‘Siah-e-Zabol’ [930 ±16 mg QuE (quercetin equivalent)/L]. In the juice of ‘Rabab-e-Pust Ghermez’ and ‘Malas-e-Saveh’ the highest concentrations of phenolic compounds were recorded [1082 ±12.8 mg GaE (gal- lic acid equivalent)/L] and tannins [6.55 ±0.5 mg TaE (tannic acid equivalent)/L], respectively. CONCLUSIONS: Significant differences were assessed between the skin and juice of the cultivars in terms of their physico-chemical properties and polyphenolic contents. The results showed higher levels of total tannins, phenolics and antioxidant activity in juice of pomegranate, whereas the skins possessed higher total flavo- noid, anthocyanin and ascorbic acid content. Further phytochemical analysis are therefore needed to identify the most representative phenylpropanoids by LC-MS (liquid chromatography coupled to mass spectrometry) and to develop novel and promising dietary supplements.