Complex sentence: Most Fritillaria (e.g. "Fritillaria imperialis", "Fritillaria meleagris") contain poisonous alkaloids such as imperialin (peiminine), which may be deadly if ingested in quantity, while others are edible.
Split into simpler sentences: Most Fritillaria (e.g. "Fritillaria imperialis", "Fritillaria meleagris") contain poisonous alkaloids such as imperialin (peiminine). Some may even be deadly if ingested in quantity, while others are edible.