Effects of Leached Spent Mushroom Compost (LSMC) on the Yield, Essential Oil Composition and Antioxidant Compounds of German Chamomile (Matricaria recutita L.)

Abstract

Leached spent mushroom compost (LSMC) in rates of 20, 40 and 60 % was used as a partial substrate for medicinal plant German chamomile (Matricaria recutita L.). A mixture of sandy loam soil and LSMC was conducted for a pot culture experiment in a green house, in a completely randomized design with six replicates for each treatment. At the end of the flowering, number, fresh and dry weight of flowers was measured. Essential oil of chamomile was isolated by Clevenger’s hydro-distillation apparatus and the components of the essential oil were identified by using gas chromatography (GC) and gas chromatographymass spectrometry (GC-MS). Moreover, enzymes and antioxidant compounds as well as photosynthetic pigments were estimated by using spectrophotometer. Analysis of variance showed that using LSMC as an organic fertilizer, significantly increased flower yield. The results also displayed, the effect of 40 % LSMC on total chlorophyll content was significant. At the highest rate of LSMC, essential oil, antioxidant compounds (polyphenols and flavonoids) and antioxidant enzymes (peroxidase and superoxide dismutase) increased significantly compared to control. The results of GC and GC-MS analysis presented that the oil of German chamomile flowers in LSMC treatments had 15 16 components and accounted for 88.2796.84 % of total essential oil. Totally, it can be concluded that application of LSMC as an organic fertilizer leads to improve yield, essential oil and antioxidant traits in German chamomile. Accordingly, we can consider LSMC could be a suitable substitute for chemical fertilizers as environmentally friendly material in growing medicinal plants.