Study on the Preparation Process of Cannabis Fructus–Astragali Radix Oral Nanoemulsion and Its Hypoglycemic Effect

ABSTRACT In this study, the Cannabis Fructus (CF, Huomaren in Chinese), the dried ripe fruit of Cannabis sativa L., and Astragali Radix (AR, Huangqi in Chinese), the dried root of Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao or A. membranaceus (Fisch.) Bge., were formulated as a Cannabis Fructus–Astragali Radix Oral Nanoemulsion (N‐CA) by using high‐pressure homogenization technology to stabilize active ingredients, improve bioavailability, and verify its hypoglycemic effect in a streptozotocin (STZ)‐induced diabetic experimental model. For method optimization, the appearance, particle size, polydispersity index (PDI), zeta potential, and centrifugal stability constant ( Ke ) were considered as evaluation indicators to preliminarily screen the dosage of CF and AR, oil phase, and pH regulator, as well as the type, dosage, and proportion of emulsifiers and co‐emulsifiers. Then, prescription optimization was conducted through Box–Behnken design (BBD) experiments to determine the optimal prescription. Finally, the hypoglycemic effect of the nanoemulsion and metformin hydrochloride group (positive drug group) was observed using the STZ model. The results showed that the average particle size of the N‐CA was 209.5 nm, PDI was less than 0.3, zeta potential ranged from −29.8 ± 1.1 to −30.8 ± 1.3 mV, the average value of Ke was 32.23%, and the pH was 6.71–6.76. In addition, it was found that medium and high doses of nanoemulsion improved the symptoms of diabetes in rats, reduced fasting blood glucose (FBG), exerted a significant therapeutic effect on blood lipids and tissue injury markers, and exhibited a protective effect on liver and kidney tissue cells. In conclusion, based on the theory of “Qi and Yin deficiency” in traditional Chinese medicine, a nanoemulsion was constructed by combining AR and CF. The innovative encapsulation of CF protein and Astragalus polysaccharides achieved a synergistic effect, providing a new functional food solution for the auxiliary treatment of diabetes.