Before an active ingredient can be isolated and studied, it's not uncommon to test the bioactivity of a naturally-isolated mixture as a first step. Often collected from honey bees, bee venom is a natural mixture that's used in the treatment of rheumatoid arthiritis, nerve pain, multiple sclerosis, allergen immunotherapy and muscle conditions like fibromyositis. In this paper, bee venom is used together with a cast of classical antibiotics (ampicillin, penicillin, gentamicin or vancomycin) against MRSA to test its antibacterial synergy. 

Read more here: http://www.mdpi.com/1420-3049/21/1/79/htm