Plant Products with Antimicrobial Properties (Edexcel International AS Biology): Revision Note

Plant Products with Antimicrobial Properties

• Plants are susceptible to attack by micro-organisms, such as bacteria and fungi

• This can cause damage to the plant and may even kill them

• Plants have developed a range of chemical defences against these microbes

  • These may include antiseptic compounds and antibiotics

• Antimicrobial chemicals from plants can be exploited by humans to develop new drugs to treat bacterial and fungal diseases

• It is possible to produce a plant extract containing these antimicrobial chemicals to test its effect on the growth of bacteria

Other therapeutic drugs sourced from plants

• Plants may also produce a variety of other compounds that can treat a range of ailments in humans, from pain killers to cancer drugs

  • Scientists were able to extract the active ingredient from willow bark, used by people for pain relief over the centuries, which led to the development of modern-day aspirin

  • Quinine is a drug sourced from the cinchona tree, used to treat and prevent malaria

• An advantage of extracting and purifying active plant compounds is the ability to produce medication that contains a known concentration of the active ingredient

  • This ensures a reliable dosage of medication

• Analysing the chemical structure of the active ingredients enables scientists to create synthetic versions of the compound in a laboratory

  • This reduces the need to remove large amounts of plant material from the environment 

  • Modifications can be made in the laboratory to make the active ingredient more effective

• The development of therapeutic drugs from plant products has enabled humans to be more successful at treating diseases