The invention belongs to the technical field of extraction of
plant effective components, and concretely relates to a low-cost and high-efficiency
curcumin extraction method. The method sequentially comprises the following steps: taking crushed dry turmeric, carrying out extraction on the crushed dry turmeric by using
ethanol, concentrating obtained extraction filtrate, extracting the concentrated filtrate with
petroleum ether, re-concentrating the obtained extract, dissolving the obtained concentrate in an
aqueous sodium hydroxide solution, extracting the obtained solution with
ethyl acetate, and concentrating the obtained
ethyl acetate layer to obtain a primary
turmeric extract; and dissolving the primary
turmeric extract in
ethanol, and carrying out high-matching
adsorption separation by adopting specially-produced modified attapulgite to respectively obtain a demethoxycurcumin and bisdemethoxycurcumin mixture and highly pure
curcumin. The method fully utilizes the structural characteristics of the
curcumin and the attapulgite, realizes high matching against the molecular difference, and has the advantages of convenience in operation, no large device demands, high extraction efficiency, low cost, effective separation of the curcumin from the demethoxycurcumin and the bisdemethoxycurcumin, high purity, and realization of industrial production.