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Charge variants are the most commonly observed sources of heterogeneity in the routine manufacturing of monoclonal antibodies. To gain further insight into the structural foundation of charge heterogeneity and its influence on biological functions, an infliximab biosimilar HS626 from a biopharmaceutical facility was isolated by semipreparative cation exchange chromatography (CEX) to obtain fractions of acidic and basic charge variants and determine the main species. It was assessed again by CEX to ensure purities. Through a series of structural and physicochemical characterizations, we concluded that the acidic variants were caused by fragments, Met oxidation, Asn deamidation, higher levels of sialylation and galactosylation of N-linked glycans, and less high mannose. The basic variants resulted mainly from aggregates, fragments, and Met oxidation. Through further analysis of antigen binding affinity, cell death inhibitory activity, ADCC, and CDC, as well as FcRn, FcγRIIIa, and C1q affinity, we demonstrated that the charge heterogeneity did not affect biological functions. This research enhances the understanding of charge variants, which are usually effective components that should not be intentionally reduced unless biological functions are affected.

To study the chemical constituents from the dried and nearly ripe fruits of Evodia (Euodia) rutaecarpa.The compounds were separated and purified by solvent and chromatographic methods. Their structures were identified by spectroscopic techniques.Fifteen compounds were separated from the normal butanol extracts of the 70% aqueous ethanol extract of the dried and nearly ripe fruits of E. rutaecarpa. Among of them, four compounds were reported in the essay and identified as diosmetin-7-O-beta-D-glucopyranoside (1), isorhamnetin-3-O-rutinoside (2), diosmin (3) and chrysoeriol-7-O-rutinoside (4).Compounds 1, 3 and 4 were separated from the dried and nearly ripe fruits of E. rutaecarpa for the first time.