Comparative analysis of chemical components of traditional Chinese medicine and antioxidants between Rosa roxburghii and R. sterilis fruits

Abstract: 【Objective】Rosa roxburghii Tratt. (Rr) and R. sterilis S. D. Shi (Rs) are both deciduous fruit crops of Rosaceae, and they are rich in a variety of bioactive compounds, including L- ascorbic acid, phenlic acid, organic acid, amino acid, triterpenes and flavonoids, so that they have high nutritional and medicinal value as well as antioxidant capacity. There are significant differences in nutritional components, pharmacological activities and antioxidant capacity between Rr and Rs fruits. However, the chemical components of traditional Chinese medicine and antioxidants in two kinds of fruits and the differences between them are not clear. Therefore, this study will identify and analyze the secondary metabolites, chemical components of traditional Chinese medicine, antioxidants and their differences between Rr and Rs fruits, so as to promote the rational application of Rr and Rs.【Methods】Ultra-high performance liquid chromatography tandem mass spectrometry (UPLC- MS/MS) was used to qualitatively and quantitatively analyze the secondary metabolites of two R. roxburghii genotypes (Rr-3; Rr-5) and R. sterilis (Rs) fruits. Searching and identifying the chemical components of traditional Chinese medicine in secondary metabolites were carried out on TCMSP platform (Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform). The ultraviolet spectrophotometry was employed to detect the capacity of three antioxidants (DPPH, 1,1-diphenyl-2-picrylhydrazyl; FRAP, fluorescence recov-ery after photobleaching; ABTS, 2,2’-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid). Identification of antioxidant substances was confirmed by correlation analysis between secondary metabolites and three antioxidant capacities (DPPH, FRAP, ABTS). The differences in the chemical components of traditional Chinese medicine and antioxidant metabolites between two types of fruits were screened, identified and compared.【Results】A total of 530 secondary metabolites belonging to 12 categories were detected (99 lipids, 90 phenolic acids, 64 amino acids and derivatives, 62 flavonoids, 57 tannins, 40 nucleotides and derivatives, 34 organic acids, 23 terpenoids, 14 alkaloids, 7 lignans and coumarins, 1 quinones and 39 other secondary metabolites), 31 metabolites were only detected in Rr and 4 metabolites (oleanolic acid-O-Hexoside-O-Hexoside, 4-aminobenzoic acid, pratensein 7-O-glucopyranoside, 4-α-Lrhamnopyranosyl-ellagic acid) were only detected in Rs. Among them, 118 metabolites belonged to TCMSP registered as chemical components of traditional Chinese medicine, 91 metabolites corresponded to 347 related targets and 359 related diseases, among them, methyleugenol, xanthine, benzoic acid, tellimagrandin Ⅰ, tercatain, glansrin C and gemin D were only detected in one or two Rr genotypes, and tercatain and salicin were key active components; 46 metabolites of anti-6 diseases corresponded to at least one disease, among which rosmarinic acid corresponded to 6 major diseases. More importantly, kaempferol-3-O-(6”-acetyl)-glucoside and kaempferol-3-O-(6”-malonyl)-galactoside were only detected in Rr, corresponding to 4 and 2 diseases, respectively. And 145 metabolites [including 38 tannins, 27 amino acids and derivatives, 23 phenolic acids, 18 nucleotides and derivatives, 13 flavonoids, 5 organic acids, 4 terpenoids, 3 lignans and coumarins, 3 lipids, 2 alkaloids, and 9 others (including vitamin C)] were significantly related to antioxidant capacity. In the difference analysis, 20 metabolites were detected only in Rr, and 1-O-galloyl-α-L-rhamnose, 2-O-Di-gallic acyl-β-D-glucopyranoside-β-D-glucopyranoside, glansrin C, 1’-O-β-D-(3, 4-dihydroxyphenethyl) -O-caffeoyl- glucoside, 3,5-Di-O- galloylshikimic acid, procyanidin trimeric monoester, tercatain, tellimagrandin I and di-p-coumaroyltartaric acid were significantly correlated with the three antioxidant capacities (p＜0.05). Variance analysis showed that there were 272 different metabolites between Rr-3 and RS, and 242 different metabolites between Rr-5 and RS. The main differential metabolic pathways between the two comparison groups were purine metabolism, pyrimidine metabolism, zeatin biosynthesis, carbon metabolism and amino acid biosynthesis. There were 171 common differential metabolites between two Rr genotypes and Rs, of which the contents of 111 metabolites were higher in Rr fruits, including 31 chemical components of traditional Chinese medicine (including the eight key active ingredients: digallic acid, guanosine, cyclic AMP, ellagic acid, gemin D, tercatain, myrianthic acid and adenosine) and 87 antioxidant metabolites, and 23 metabolites (malonic acid, cytosine, histamine, fumaric acid, thymine, L- glutamic acid, xanthine, pyridoxine, gallic acid, methyl gallate, sinapyl alcohol, uridine, guanosine, ellagic acid, digallic acid, rosmarinic acid, gemin D, pedunculagin, tellimagrandin Ⅰ, glansrin C, pterocarinin A, glansrin A and platycaryanin A) were both antioxidants and chemical components of traditional Chinese medicine. The contents of 53 substances (including 16 phenolic acids, 11 flavonoids, 8 lipids, 6 amino acids, 3 tannins, 3 terpenoids, 3 organic acids, 1 lignans and coumarins, and 2 others) in Rs were higher, including 10 chemical components of traditional Chinese medicine. Further analysis of the antioxidant capacity of fruits showed that, the DPPH, ABTS and FRAP antioxidant capacities of Rr were significantly higher than those of Rs.【Conclusion】The above results showed that the Rr fruit had stronger traditional Chinese medicine activity and antioxidant capacity than Rs fruit. Thus, it had higher medical and health value and development potential as a functional food. It was clear that phenolic substances were the most important antioxidant substances and chemical components of traditional Chinese medicine in Rr and Rs fruits; The amount and content of phenolic compounds in Rr and Rs fruits were the main reasons for thedifference in antioxidant capacity and Chinese medicine activity.