Effect of salt stress on alkaloid content (galanthamine and lycorine) and antioxidant activities (enzymatic and non-enzymatic) of snowflake (Leucojum aestivum L.)

Summer snowflake (Leucojum aestivum L.) is a bulbous plant belongs to Amaryllidaceae family. L. aestivum is a Euro-Mediterranean region plant and is a well-known source of pharmacologically important alkaloids. Galanthamine is the major bioactive compound that is widely used in the treatment of neurological disorders, including Alzheimer's disease. Another alkaloid lycorine has antitumor, antimalarial, hepatoprotective, antiviral, antifungal and antiparasitic activities. Objective of this study is to determine the effect of different salt stress treatments on galanthamine and lycorine amounts, growth and development, non-enzymatic antioxidant activity (free radical scavenging activity-DPPH and total phenol-flavonoid content) and enzymatic antioxidant activity (SOD and CAT) in L. aestivum. The plant was cultivated for 3.5 months watering with 3 different concentrations (2, 4 and 8 g/L) of 2 different salt types (NaCl and CaCl2). Obtained leaves and bulbs were extracted with methanol and analyzed with HPLC-DAD system. Galanthamine and lycorine amount were enhanced with 4 g/L CaCl2 in the bulbs. Galanthamine in the leaves was also improved with 8 g/L NaCl. Salt stress treatments did not change the shoot length, bulb size and water content percentage significantly. Salt stress caused by 4 g/L CaCl2 increased the antioxidant activity only in the leaves and total phenol-flavonoid content in the bulbs. Antioxidant enzymes also elevated with some salt stress treatments in the bulbs and leaves.