What is horizontal natural product transfer, and why is it important?

Horizontal natural product transfer is when plants absorb natural compounds released from decaying plant material by nearby living plants. This is important because it shows how plants interact with their environment and if they can change these borrowed compounds for their benefit. This process may change our understanding of plant ecology and interactions, potentially affecting plant health and ecosystem dynamics.

How do plants absorb chemicals, and why is this significant?

Plants absorb natural and synthetic compounds, known as xenobiotics, through their roots or leaves and move them throughout their tissues. Previously, studies focused on man-made chemicals, but the focus has shifted to natural products from other plants. This is significant because it broadens our understanding of plant interactions and their ability to process various compounds from their surroundings.

What is umbelliferone, and why was it used in the plant study?

Umbelliferone is a natural compound (specifically a coumarin) used in research to study horizontal natural product transfer because it’s easily detectable. Its uptake and modification by plants helps show how plants might handle other, more complex natural compounds, revealing the mechanisms and ecological roles of this transfer process. It is a model compound that allows understanding of how plants modify chemicals from other plants.

What did the plant study reveal about how plants handle umbelliferone?

The study found that various plant seedlings (barley, radish, pea, flax, and garden cress) absorbed umbelliferone from hydroponic solutions. More impressively, garden cress modified umbelliferone into esculin, while barley transformed it into scopoletin. This is important because it showed plants don't just passively absorb compounds but actively modify them, similar to how they detoxify human-made chemicals.

What are Cytochrome P450 enzymes, and what role do they play in plant's modification of other plant's compounds?

Cytochrome P450 enzymes are believed to be responsible for the modification of absorbed compounds like umbelliferone. They are similar to those that plants use to detoxify xenobiotics. Researchers used naproxen, an inhibitor of cytochrome P450 enzymes, to confirm that these enzymes are likely responsible for the conversion of umbelliferone to scopoletin and esculin. This highlights the active metabolic processes plants use to interact with their chemical environment.

Plants exchanging chemical compounds.

Can Plants Absorb and Transform Chemicals from Other Plants?

Lena Voss in Science & Nature September 2025 • 4 min read.

"Unveiling the surprising phenomenon of horizontal natural product transfer and its implications for plant health and environmental science."

Plants are constantly exposed to a cocktail of chemicals in their environment, many of which originate from human activities. These compounds, known as xenobiotics, can be absorbed by plants through their roots or leaves and then translocated throughout their tissues. For a long time, research focused mainly on these human-made chemicals, but recently, scientists have discovered that plants also take up natural products from other plants.

This phenomenon, called "horizontal natural product transfer," occurs when natural compounds are released from decaying plant material and then absorbed by nearby living plants. This raises fascinating questions about how plants interact with their environment and whether they can modify these borrowed compounds to their benefit.

To investigate this further, researchers studied the uptake and modification of a specific natural compound, umbelliferone, in various plant seedlings. Umbelliferone, a type of coumarin, is easily detectable and served as a model to explore the broader implications of horizontal natural product transfer.

How Plants Absorb and Change Umbelliferone

The study involved growing seedlings of barley, radish, pea, flax, and garden cress in hydroponic solutions containing umbelliferone. After a week, the researchers analyzed the plant tissues to see if umbelliferone had been absorbed. The results were striking: all five plant species had taken up significant amounts of umbelliferone.

What's even more fascinating is that some plants modified the absorbed umbelliferone. Garden cress converted it into esculin, while barley transformed it into scopoletin. These transformations are similar to how plants detoxify xenobiotics, using enzymes to alter the chemical structure of the absorbed compounds.

Uptake Confirmation: HPLC analyses confirmed that umbelliferone was absorbed into the aerial parts of all seedlings.
Modification in Specific Plants: Garden cress hydroxylated and glucosylated umbelliferone to esculin, while barley seedlings methoxylated it to scopoletin.
Enzyme Involvement: Cytochrome P450 enzymes, known for modifying xenobiotics, are likely responsible for these transformations.

To confirm the involvement of these enzymes, the researchers used naproxen, a known inhibitor of cytochrome P450 enzymes. When naproxen was added to the hydroponic solutions, the conversion of umbelliferone to scopoletin in barley and to esculin in garden cress was significantly reduced. This further supports the idea that plants actively modify absorbed compounds using their metabolic machinery.

What This Means for Plant Science and Ecology

This study demonstrates that plants can absorb and modify phenolic compounds from their environment, expanding our understanding of horizontal natural product transfer. This phenomenon likely plays a more significant role in plant ecology than previously thought, influencing how plants interact with each other and their surroundings. Further research is needed to explore the full extent of this process and its implications for plant health and ecosystem dynamics.