Abstract
Background: Medicinal plants are considered a very important source of natural crude materials which are used in pharmaceutical industries. Nowadays, many investigators focused their studies for medicinal plants in order to extract components which have effects as antibacterial and antioxidant activities, also, some diseases such as diabetes, cardiovascular, diarrhea, antitumor and anticancer, etc. Our study focused in the biochemical characterization of Portulaca oleracea and Carthamus tinctorius to study their antidiabetic activity in alloxan induced diabetes in rats.
Methods: Extracts from Portulaca oleracea leaves and Carthamus tinctorius flowers were prepared then their total phenolic and flavonoid content and identification by HPLC technique were analyzed. Moreover, the antioxidant activity using (FRAP and DPPH radical) were determined. Randomly allocated male white Wistar rats into four groups of five each: non-diabetic control; diabetic control; diabetic treated with Carthamus tinctorius extract (200 mg kg-1 BW); diabetic treated with Portulaca oleracea extract daily (250 mg/kg), then pancreatic tissues were collected and routinely processed for histopathological examination.
Results indicate that methanolic extract of Portulaca oleracea leaves had the largest total polyphenols and flavonoids content, which were 129.03 mg GAE/g and 22.55 mg QE/g, followed by Carthamus tinctorius flowers methanolic extract, which were 102.44 mg GAE/g and 13.94 mg QE/g, respectively. Identification of total polyphenols and flavonoids were estimated by HPLC. The methanolic extract of Portulaca oleracea leaves, had the highest reducing power which was 1.921 at the concentrations of 80 mg/ml. followed by Carthamus tinctorius flowers extract. Also, by using (DPPH+), the highest antioxidants activity was for Portulaca oleracea leaves extract. Microscopic examination of pancreatic tissues from rats treated with Portulaca oleracea and Carthamus tinctorius revealed their anti-diabetic activity with improved histological tissue changes compared with alloxan induced diabetic group. Moreover, antidiabetic activity of Portulaca oleracea recorded more histological improvement than that of Carthamus tinctorius compared with the control non diabetic group.