Quality control, preparation process optimizing and anti-inflammatory effects of Premna Puberula Pamp. Pectin

Background: Premna Puberula Pamp. Pectin (PP) was a Wudang functional food in China. It has the effect of dispelling fire, clearing heat and detoxification in folk medicine. However, little studies have been reported for their preparation, quality control, effects and toxicity.Methods: The P. Puberula leaves were collected from different pharms and seasons. The compounds in PP were identified using UPLC-Q-TOF-MS/MS. UV-VIS spectrophotometry with phenol-sulfuric acid and sodium nitrite aluminum nitrate were conducted for analyzing the water-soluble sugars and total flavonoids, respectively. L9(34) orthogonal experimental method was used to optimize the preparation process of PP. For the pharmacological effects of PP, the swelling right hind paw of ICR mice was modeled using subcutaneous injection of carrageenan gum solution, and the local tissue inflammatory reactions of the model mice were investigated using vernier calipers and HE staining. The serum inflammatory factor expression was detected using ELISA. The acute toxicity experiments were carried out for safety assessment of PP in ICR mice.Results: Fifty-three compounds were initially identified in PP among which flavonoids were dominant (19 out of 53). The average values of water-soluble sugar content and total flavonoid content of PP were 13.366 and 4.970 mg/g, respectively. The best preparation process of PP was powder-liquid ratio 1: 20, temperature 90 degrees C, and stirring time 3 min. Data showed that PP reduced paw edema and decrease the serum level of IL-6, TNF-alpha and IL-1 beta in the model mice. There was no toxic effect of PP on mice at a total dose of 6000 mg/kg/24h. Conclusion: In summary, by optimizing the preparation process, PP with stable quality can be obtained. PP has anti-inflammatory effects without toxicity.