Abstract
Cuscuta campestris is a holoparasitic plant that depends on the host for water, nutrients, and photosynthetic substances. The purpose of this research was to evaluate the effects of the host species on the content of bioactive and health-promoting substances in the Cuscuta seeds to test the following hypothesis: these substances are more induced if the hosts are herbs. The studied hosts were herbs (thyme, basil, and onion) and non-herbs (alfalfa and tomato). The results showed that the carotenoid accumulation in seeds developed on basil and thyme was the maximum. The extracts of seeds grown on thyme and onion had significantly more galactitol, total polysaccharide, and antioxidant activity than other hosts. Quercetin, kaempferol, and total flavonoids were higher in the seeds set on onion. The highest content of bergenin was recorded on thyme with no significant difference with onion. The extract of seeds grown on thyme had more total phenolics, followed by tomato and basil. Analysis of the phytosterol content of the seeds showed that campesterol was the minimum in seeds grown on alfalfa and stigmasterol was lowest in seeds grown on tomato than other hosts. Additionally, β-sitosterol increased in seeds developed on basil, onion, and thyme, and Δ7-avenasterol increased in seeds set on thyme and basil. Overall, the content of total phytosterols was higher in seeds developed on basil, onion, and thyme. The results were suggestive of the proper health-promoting levels of dodder seeds developed on medicinal plants such as onion and thyme for pharmaceutical and food applications.