How a Plant Hormone Unlocks a Potent Anti-Cancer Compound
A single spray of a plant hormone can dramatically increase the levels of a little-known molecule with significant health-promising properties, transforming ordinary kale into a potential superfood.
When you think of healthy vegetables, kale likely comes to mind—a leafy green renowned for its nutritional density. Yet, hidden within its leaves is a biochemical secret that scientists are just beginning to understand. When kale plants are sprayed with a natural plant hormone called methyl jasmonate, they become supercharged, producing dramatically higher levels of health-promoting compounds. Among these is a remarkable molecule called neoascorbigen, which has shown exciting potential in laboratory studies for its ability to help combat cancer 1 . This article explores how this simple agricultural treatment can unlock a powerful, naturally occurring defense mechanism in kale, turning a common vegetable into an even more potent ally for human health.
To understand neoascorbigen, we must first look at the unique system that Brassicaceae vegetables like kale, broccoli, and cabbage use for self-defense. These plants contain natural compounds called glucosinolates 2 . When the plant is damaged—say, by an insect biting into a leaf—these inert compounds come into contact with an enzyme called myrosinase, triggering a chemical reaction that produces a range of biologically active breakdown products 3 . These products, which include isothiocyanates and indoles, are the plant's first line of defense, deterring herbivores with their pungent, sometimes toxic effects .
For humans, however, these same defensive compounds offer remarkable health benefits. Extensive research has correlated the consumption of Brassica vegetables with a reduced risk of various cancers, including lung, colon, breast, and prostate cancers 2 .
The hydrolysis products of glucosinolates have been identified as key players in this protective effect, primarily through their ability to activate the body's phase II detoxification enzymes 1 2 . These enzymes, including quinone reductase (QR), help the body neutralize and eliminate potential carcinogens, providing a powerful cancer-preventive mechanism 1 .
Neoascorbigen is one such beneficial compound. It is a hydrolysis product derived from a specific glucosinolate called neoglucobrassicin 1 . While not as famous as sulforaphane—the well-studied compound from broccoli—neoascorbigen is emerging as a significant contributor to the health-promoting profile of Brassica vegetables, particularly when these plants are stimulated to enhance their natural defenses.
Inert compounds in plant tissue
Releases myrosinase enzyme
Forms bioactive compounds
Anti-cancer effects in humans
Glucosinolates act as natural pesticides, deterring herbivores from eating the plant.
These same compounds offer cancer-preventive benefits when consumed by humans.
Enzyme-mediated hydrolysis transforms inert compounds into bioactive forms.
To test the practical application of this discovery, researchers designed a series of field experiments to see if they could reliably enhance these beneficial compounds in kale using methyl jasmonate (MeJA), a plant hormone that naturally triggers defense responses 1 .
The research followed a clear, methodical process:
Researchers grew two different kale varieties and sprayed them with 250 µM methyl jasmonate four days before harvest 1 .
Samples were collected from both apical (younger) and basal (older) leaves to compare responses 1 .
Using HPLC, scientists measured concentrations of glucosinolates and their breakdown products 1 .
Extracts were tested for their ability to induce quinone reductase (QR) activity, a key anti-carcinogenic biomarker 1 .
The results were striking. The methyl jasmonate treatment acted as a powerful switch, turning up the plants' production of valuable phytochemicals.
The table below shows the dramatic percentage increase in key glucosinolates in the apical leaf tissue of MeJA-treated kale compared to untreated control plants, averaged over two growing seasons 1 :
| Glucosinolate Compound | Percentage Increase after MeJA Treatment |
|---|---|
| Gluconasturtiin | 56% |
| Glucobrassicin | 98% |
| Neoglucobrassicin | 150% |
Even more importantly, the hydrolysis products of these glucosinolates—the biologically active molecules—saw an even more dramatic rise. The following table illustrates the surge in these key compounds, including neoascorbigen, as reported in a related study on broccoli 5 :
| Glucosinolate Hydrolysis Product | Percentage Increase after MeJA Treatment |
|---|---|
| Sulforaphane | 152% |
| Phenethyl Isothiocyanate | 318% |
| N-methoxyindole-3-carbinol | 313% |
| Neoascorbigen | 232% |
The most critical finding was the effect on biological activity. Extracts from the MeJA-treated kale tissue showed a significant increase in quinone reductase (QR) induction 1 . Statistical correlation analysis revealed that this increased QR activity was strongly linked to the elevated levels of several hydrolysis products, including sulforaphane, N-methoxyindole-3-carbinol, and neoascorbigen 1 5 .
This suggests that the health-promoting effect is not due to a single "magic bullet" compound, but rather the combined, synergistic action of multiple enhanced phytochemicals working together 1 .
Furthermore, the study found that the younger apical leaf tissues had a much more vigorous response to the MeJA treatment than the older basal leaves, exhibiting greater increases in phenolics, glucosinolates, and QR activity 1 . This indicates that the plant's developmental stage is a crucial factor in its capacity to produce these protective compounds.
The research into neoascorbigen and glucosinolate induction relies on a specific set of tools and reagents. The following table details some of the essential components used in this field of study.
| Research Reagent / Material | Function in Experimentation |
|---|---|
| Methyl Jasmonate (MeJA) | A plant hormone used as an elicitor. When sprayed on crops, it mimics an attack, triggering the plant's defense system and boosting the production of secondary metabolites like glucosinolates 1 5 . |
| Quinone Reductase (QR) Assay | A biomarker used to measure the anti-carcinogenic potential of plant extracts. Increased QR activity indicates a stronger ability to induce phase II detoxification enzymes 1 . |
| High-Performance Liquid Chromatography (HPLC) | An analytical technique used to separate, identify, and quantify the individual glucosinolates and their hydrolysis products present in a plant tissue sample 1 . |
| Myrosinase Enzyme | The endogenous plant enzyme that hydrolyzes glucosinolates. It is crucial for converting stored glucosinolates into active breakdown products like neoascorbigen and sulforaphane during analysis or digestion 3 . |
| Triton X-100 | A surfactant (detergent) added to MeJA spray solutions to help the solution spread evenly and stick to the waxy surfaces of plant leaves, ensuring effective absorption 1 . |
Natural plant hormone that triggers defense responses when applied to crops, boosting production of beneficial compounds.
Advanced analytical technique used to precisely measure concentrations of glucosinolates and their breakdown products.
Biomarker test that measures the ability of plant extracts to induce phase II detoxification enzymes in cells.
The discovery that a simple methyl jasmonate spray can significantly enhance the formation of health-promoting compounds like neoascorbigen in kale opens up exciting possibilities for the food and agriculture industries. This natural treatment offers a viable strategy to create "functional foods" with enhanced cancer-fighting potential 5 . By understanding and harnessing the plant's own defense mechanisms, we can improve the nutritional quality of the vegetables we consume.
MeJA treatment could be applied to commercially grown kale and other Brassica vegetables to boost their health-promoting compounds.
Using natural plant hormones to enhance crop nutritional value represents an eco-friendly approach to food production.
The research on neoascorbigen is part of a broader shift towards viewing food not just as a source of sustenance but as a vital component of preventive healthcare. As we continue to unravel the complex interactions between plant phytochemicals and human physiology, the humble kale leaf, supercharged by its own natural processes, stands as a powerful testament to the potential hidden within the plant kingdom. The future of nutrition may well depend on our ability to listen to and amplify the subtle chemical conversations that plants have been having for millions of years.