tannins
Tannins are astringent polyphenolic compounds produced by plants that bind strongly to proteins, amino acids, and other organic molecules. In plant science, they play key roles in defense against herbivores and pathogens, and are studied for their contributions to plant stress responses, fruit ripening, and seed protection. Understanding tannin biosynthesis and function helps researchers explore how plants adapt to environmental pressures and interact with their ecosystems.
open_in_new WikipediaPubMed · 2026-04-10
Tadpoles raised in natural pond water — full of microbes — were larger and healthier, and their gut bacteria responded meaningfully to a tannin-rich diet, reducing potentially harmful bacteria. Tadpoles in sterile lab water showed none of these benefits, suggesting lab-only experiments miss key real-world biology.
Tadpoles raised in natural pond water had greater body mass and length compared to those in sterilized water, though dietary tannins (2% tannic acid) had no effect on body size.
Gut bacterial diversity was significantly higher in tadpoles from natural pond water than in those from autoclaved (microbially depleted) water.
Dietary tannins reduced bacterial diversity and lowered the relative abundance of potentially pathogenic bacterial genera — but only in tadpoles raised in microbially rich natural water, not in sterile lab conditions.