In Parts I and II of “Daylily—the Herb of Forgetting Worries”, we have already learned that the plant’s reputation is rooted not only in ancient folklore but is also supported by modern scientific evidence. We also revealed the delicate mechanism through which daylily exerts its effects along the gut microbiota–gut–brain axis.

But a key practical question naturally follows:In daily life, what we usually consume are dried or fresh flower buds—are these really the forms with the strongest mood-supporting activity?  Do different plant parts or extraction methods lead to different levels of bioactivity?

A joint research team from World-Way and Hunan Agricultural University published a study in 2022 in Frontiers in Pharmacology [1] that directly addressed this question through a rigorous scientific “competition,” offering a precise “optimal solution” for the development of next-generation emotional wellness ingredients.

I. A Scientific “Race”: Comparing the Activity of Six Extracts

To identify the most potent antidepressant form of daylily, the research team conducted a comprehensive and systematic comparative experiment. Rather than relying on any single raw material, they set up multiple “contestants”:

• Three plant parts: fully bloomed flowers, fresh flower buds, and the commonly consumed dried flower buds

• Two extraction methods: water extract and 80% ethanol extract

By combining plant parts with extraction solvents, the researchers ultimately obtained six distinct daylily extracts.  They evaluated these six extracts using the internationally recognized chronic unpredictable mild stress (CUMS) model of depression.

II. A Surprising Discovery: Why the Flower and Water Extract Matter Most

The outcome of this scientific “race” may overturn our traditional understanding of daylily.

The results clearly showed that the flower water extract (HCW) exhibited the most pronounced antidepressant-like activity.

This conclusion is supported by two key findings:

1. Flowers outperform buds

The study confirmed that extracts from daylily flowers—both the water extract (HCW) and the ethanol extract (HCE)—showed significant antidepressant-like effects.  By contrast:

• Extracts from fresh flower buds and dried flower buds were clearly inferior

• And notably, the extracts of dried flower buds (DHCW and DHCE)—the form we most commonly consume—“did not exhibit any noteworthy antidepressant activity.”

This suggests that the dried buds we choose for convenience of storage and transport may actually miss the plant’s most powerful active form.

1. Water extraction outperforms ethanol extraction

Even when comparing extracts from the same plant part (the flower), the research team found differences:

• The flower water extract (HCW) performed better than

• The flower ethanol extract (HCE)

This implies that water, as a highly polar solvent, is better able to extract the key compounds responsible for daylily’s mood-modulating effects.

III. More Than Just Rutin: Decoding the Flower’s “Active Matrix”

Why is the flower water extract (HCW) the most effective?

As discussed in earlier chapters, rutin is one of the key active compounds—but it is far from the whole story.

Using HPLC-Q-TOF-MS, the researchers identified 32 major constituents within the highly active HCW extract.  This reveals a complex “active matrix,” which includes:

• 18 flavonoids

• 7 chlorogenic-acid–type compounds

• Various phenolics, alkaloids, and saponins

For example, the team identified several high-abundance active constituents such as:

• Quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside

• Several coumaroyl-quinic acid derivatives

Synergy: 1 + 1 > 2

The most elegant aspect of this study is the demonstration that “the whole is greater than the sum of its parts.”  When rutin (RT) was tested alone, it did show antidepressant-like activity—but its ability to modulate gut microbiota (such as Bacteroides and Desulfovibrio) was weaker than the full flower water extract (HCW), which contains all 32 compounds.

This confirms that the antidepressant effect of daylily flowers relies on the synergistic interactions among dozens of compounds within the active matrix, rather than any single ingredient acting alone.

IV. Precision Unlocks the True “Forget-Worry” Power

This study provides unprecedented precision for the modern application of daylily. It shows that developing a truly effective emotional wellness ingredient requires moving beyond traditional bud-based consumption habits.

• Precise selection:

Use the fully bloomed flowers, not the flower buds.

• Precise extraction:

Use water extraction, which preserves the full spectrum of active compounds.

• Precise understanding:

Recognize the importance of the 32-compound active matrix, rather than relying on a single constituent such as rutin.

Only through this scientific precision—in raw material, process, and conceptual understanding—can we fully unlock the emotional wellness potential of daylily flowers and allow this ancient “herb of forgetting worries” to release its complete therapeutic power under modern scientific light.

Reference

[1] Liu, J., Ye, T., Yang, S., Zhong, X., He, W., Xu, M., Fang, J., Deng, M., Xu, N., Zeng, J., & Qing, Z. (2022). Antidepressant-like activity, active components and related mechanism of Hemerocallis citrina Baroni extracts. Frontiers in Pharmacology, 13, 967670. https://doi.org/10.3389/fphar.2022.967670