propolis is a kind of colloidal substance formed by honeybees from plant spore or tree trunk and mixed with their own secretions. It is generally recognized that it has the functions of regulating blood lipids, blood pressure, blood sugar and other health functions. But propolis production is scarce, known as "purple gold". According to the figures released by China Bee Products Association, the output of propolis in China is about 300 tons per year. However, according to industry sources, the actual sales volume of propolis in China is nearly 1000 tons per year. Where did these extra propolis come from? The head of Yu Feng Yuan bee industry limited, Changge, Henan, admitted that the number of genuine natural propolis was scarce. After purification, the price per kilogram was as high as 700 yuan. What they are making is not natural propolis, but a relatively cheap gum. It turns out that quercetin and rutin are artificial flavonoids, mainly in the process of using "gum" to produce the so-called "purify propolis," which is added to the customer's requirements to improve the total flavone content. The "flavonoids" mentioned by the responsible person is called "total flavonoids" in the national standard of propolis. According to the national standard, "total flavonoids" is an important index for testing propolis. Propolis has a good health effect because the propolis contains a large number of flavonoids, but this substance can not be synthesized in the human body and can only be taken from the diet. According to the person in charge, "gum" also contains flavonoids, so it will be used as a fake propolis.