Polygonatum cyrtonema is a perennial plant, and it has long been used in traditional Chinese medicine for food and medicine. The medicinal part of Polygonatum cyrtonema is the underground rhizome; however, the aerial part has not been studied so far for its medicinal activity. To promote the growth of underground rhizomes, the topping of aboveground plants of Polygonatum cyrtonema has been conducted. To understand the effect of the topping of aerial parts on the yield and medicinal components

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... rhizomes, the present study was conducted. Also, the chemical constituents, antioxidant, and in vitro hypoglycemic activities of the aerial stem, leave, and flower parts of Polygonatum cyrtonema were analyzed. The results showed that compared to the control (CK) treatment, the topping of the aerial part increased rhizome weight gain coefficient (3.43) significantly than the CK treatment (2.63). Moreover, the topping of the aerial part induces the biosynthesis of bioactive compounds. As such, the polysaccharide content in the rhizome (8.80%) and the total saponin content (37.60 mg/g) was significantly (P < 0.01) higher than CK treatment. The contents of total phenols and total flavonoids in PCL and PCF were significantly (P < 0.01) higher than those in rhizomes; however, the polysaccharide content (10.47%) in PCR (whole rhizome) was higher than that in PCS (3.65%), PCL (5.99%), and PCF (4.76%) content. The protein and amino acid contents in PCS, PCL, and PCF were higher than those in rhizomes. The protein and amino acid contents in PCS, PCL, and PCF were higher than those in rhizomes. PCS, PCL, and PCF showed strong antioxidant activities (DPPH, ·OH, ABTS, and FRAP), which were better than traditional medicinal parts ( the rhizome). To sum up, the topping measures can improve the rhizome yield of Polygonatum cyrtonema and the medicinal components of the rhizomes, which can be applied to improve production. The stems, leaves, and flowers had a much stronger antioxidant activity and higher the total polyphenols, flavonoids, proteins, and amino acid content. Therefore, stems, leaves, and flowers of Polygonatum can be fully developed according to different needs. they are typically used in animal feed, food storage and cosmetics.