University of Hawaiʻi researchers uncover the remarkable health potential of the humble Poha Berry
We've all heard the age-old advice to "eat the rainbow" for better health. But what if one of the most powerful health-promoting fruits isn't a vibrant blueberry or a dark leafy green, but a humble, golden berry often found growing in backyards? Scientists at the University of Hawaiʻi at Hilo's Daniel K. Inouye College of Pharmacy are turning their attention to the Poha Berry, also known as the Cape Gooseberry, and their discoveries are revealing a treasure trove of potential for fighting two of modern medicine's greatest foes: chronic inflammation and cancer .
The Poha berry (Physalis peruviana) is also known as the Cape Gooseberry, Inca berry, or golden berry. It's native to South America but grows abundantly in Hawaii and other tropical regions.
The Poha berry (Physalis peruviana) is a bright, orange-yellow fruit encased in a papery husk. While it's a beloved snack in many cultures, it's its hidden molecular machinery that has scientists excited. The berry is packed with a class of compounds called withanolides .
Think of withanolides as the plant's sophisticated chemical defense system. These naturally occurring steroids help the plant ward off pests and diseases. For humans, however, these compounds can act as powerful bioactive agents. When we consume them, they interact with our own cellular pathways, often with therapeutic effects. Researchers theorize that these withanolides can "talk" to our cells, instructing them to dial down harmful processes—like rampant inflammation—or even self-destruct if they become cancerous .
Withanolides belong to a class of compounds called steroidal lactones. Their unique molecular structure allows them to interact with various cellular receptors and enzymes in the human body, potentially modulating inflammation pathways and triggering apoptosis (programmed cell death) in cancer cells.
To move from theory to fact, science requires rigorous experimentation. A pivotal study conducted at the Daniel K. Inouye College of Pharmacy aimed to do just that: isolate the active compounds from Poha berries and test their effects directly on human cancer cells .
The goal was clear: extract compounds from the Poha berry and analyze their ability to inhibit the growth of human colon cancer cells.
Researchers started by drying and grinding Poha berries into a fine powder. They then used a series of solvents to separate the complex mixture of plant chemicals into different fractions, each containing compounds with similar properties.
The most promising fraction was put through advanced chromatography techniques—a process that acts like a molecular sorting machine—to isolate pure, individual withanolide compounds.
Human colon cancer cells were grown in lab plates under controlled conditions.
These cancer cells were then treated with various concentrations of the isolated withanolides. A control group of cells was left untreated for comparison.
After a set period (usually 24-72 hours), a chemical assay was used to measure cell viability. This test changes color based on the number of living cells, allowing scientists to quantify how effectively the treatment killed the cancer cells.
The results were striking. The treated cancer cells showed a significant, dose-dependent reduction in viability. In simpler terms, the more withanolide they were given, the more cancer cells died.
The data revealed two key findings:
This table shows how the percentage of living cancer cells decreases as the concentration of the withanolide increases.
| Withanolide Concentration (µg/mL) | Cancer Cell Viability (% of Control) |
|---|---|
| 0 (Control) | 100% |
| 10 | 75% |
| 25 | 45% |
| 50 | 20% |
| 100 | 8% |
This table compares the ability of different Poha berry fractions to inhibit a key inflammatory enzyme (COX-2).
| Sample Tested | COX-2 Inhibition (%) |
|---|---|
| Pure Withanolide A | 92% |
| Poha Berry Fraction 3 | 85% |
| Poha Berry Fraction 7 | 78% |
| Standard Drug (Ibuprofen) | 65% |
This table lists some of the specific beneficial compounds found in the research.
| Withanolide Compound | Potential Primary Activity |
|---|---|
| Withanolide A | Anti-cancer, Anti-inflammatory |
| Withanolide B | Anti-inflammatory |
| Physalin F | Immunomodulatory |
What does it take to conduct such an experiment? Here's a look at some of the essential tools and reagents used in this type of pharmacological research.
| Research Tool / Reagent | Function in the Experiment |
|---|---|
| Cell Culture Lines (e.g., HCT-116 colon cancer cells) | Provide a standardized, human-relevant model to test the effects of compounds in a controlled lab environment. |
| MTT Assay Kit | A key reagent used to measure cell viability. It changes color in the presence of metabolically active (living) cells. |
| Chromatography Equipment (HPLC) | The "molecular sorting machine" that separates and purifies individual chemical compounds from a complex plant extract. |
| Solvents (e.g., Methanol, Ethyl Acetate) | Used to dissolve the plant material and extract the bioactive compounds based on their solubility. |
| Inflammatory Enzyme Kits (e.g., COX-2 Inhibitor Screening Kit) | Allows scientists to directly measure how effectively a compound can block the action of a specific inflammation-causing enzyme. |
The journey of the Poha berry from a backyard plant to a subject of intense scientific study is a powerful reminder that nature still holds many secrets. The work at the Daniel K. Inouye College of Pharmacy provides compelling early evidence that this golden berry is a rich source of compounds with significant anti-inflammatory and anti-cancer properties .
It's important to remember that this is foundational research. The next steps will involve testing in animal models, ensuring safety, and ultimately, clinical trials in humans.
But the promise is undeniable. So, the next time you see a Poha berry, remember that within its sunny glow lies not just a burst of tropical flavor, but a complex and potent chemistry that science is just beginning to understand—a golden secret with the potential to inspire the next generation of natural medicines.