A study published in Signal Transduction and Targeted Therapy in 2026 by researchers from Nanjing University found that traditional water decoction preserves the antiviral plant microRNA MIR2911 in honeysuckle. The study indicated that ethanol-based processing removes most of this RNA and reduces its associated bioactivity.

The research used MIR2911, a microRNA enriched in honeysuckle, as a proof-of-concept. RNA isolated from traditional decoction suppressed Japanese encephalitis virus (JEV) replication in cultured cells. Conversely, RNA from ethanol-processed materials and commercial products exhibited little to no comparable antiviral effect against JEV. The study showed that MIR2911 directly targets multiple regions of the JEV genome and requires AGO2 to exert its antiviral effect. When AGO2 was deleted, MIR2911 no longer suppressed viral replication; when AGO2 was restored, the antiviral effect returned.

In a simulated ethanol-based workflow, MIR2911 levels in the retained preparation decreased by 93.6% compared with the original aqueous decoction. Several marketed honeysuckle-containing products processed through similar methods contained little to no detectable MIR2911. The study also demonstrated that exosomes isolated from healthy volunteers' serum after consuming honeysuckle decoction suppressed JEV replication in cell experiments.

The research team developed a recovery-corrected quantification system to measure MIR2911 across complex samples. The study determined that MIR2911 was most abundant in unopened flower buds and that its levels varied across different production regions. Oven drying preserved MIR2911 more effectively than air drying, showing approximately a 3.2-fold difference in preservation.

The study also found that high-temperature moist-heat sterilization substantially degraded MIR2911. However, adjusting the decoction to a mildly acidic pH before sterilization improved RNA stability. The authors of the study stated, "Some botanical medicines may contain not only chemical actives, but also information-bearing biological components whose fate depends on manufacturing." They further added, "A process may preserve one layer of activity while unintentionally removing another."