Plant tissue cultures of eucalyptus tree cells have greater anti-inflammatory properties than naturally grown leaves.
A recent study shows that plant tissue culture techniques on Eucalyptus camaldulensis can increase the production of beneficial secondary metabolites (phytochemicals), which have a significant impact against inflammation.
Harnessing the power of a full-grown tree in a test tube
The eucalyptus tree, known as the river red gum tree, can reach 150 feet. Its leaves have long been used to treat ailments, including malaria and flu symptoms. A research team from Delta University for Science and Technology and two additional Egyptian universities have advanced these uses by employing plant tissue culture. They grew and multiplied plant cells in test tubes to produce higher levels of beneficial compounds than found in natural trees.
Totipotency: From a single cell to multitudes
Plant tissue culture technology is useful for studying various aspects of plant life, including plant genes, reproduction, crop quality, and beneficial plant chemicals (phytochemicals). The principle behind this technique is that an individual plant cell possesses “totipotency,” meaning it can develop into an entire plant.
The key regulators of plant cell growth in controlled lab experiments are plant hormones called auxin and cytokinin. The balance between these hormones plays an important role in determining both the quantity and quality of the beneficial plant compounds (phytochemicals) produced.
Having considered the technological background, it’s essential to focus on what these compounds mean for human health.
Few studies have examined secondary metabolite production in gum tree tissue cultures. Existing research indicates that controlled light exposure and hormonal regulation (auxin and cytokinin) can enhance the production of bioactive volatile oils, notably 1,8-cineole (eucalyptol), in E. camaldulensis. Compounds such as cis-sabinol, globulol, α-eudesmol, and others from E. camaldulensis have been shown to inhibit pro-inflammatory markers, including COX-2, TNF, and IL-6. This tree also contains antioxidative compounds, such as spathulenol and p-cymene.
Building on this, the team at Delta University conducted a study examining the chemical profile of cultured callus (a mass of undifferentiated plant cells grown in vitro). Their work included volatile oil analysis using gas and liquid chromatography, which are laboratory techniques that separate and identify chemical compounds. They also assessed the biological activity of these compounds by evaluating inflammatory markers (such as TNF-α and IL-6) and antioxidative capacity.
With this groundwork established, let’s look at how researchers actually grow enhanced plant tissue cultures in the lab.
The research team collected fresh E. camaldulensis leaves from Antoniades Garden, Alexandria, Egypt. They dried, ground, and stored these natural leaves until extraction. Another set of leaves underwent plant tissue culture, in which plant cells are grown and multiplied in sterile test tubes with nutrient medium.
The researchers submerged leaf cuttings in nutrient media to encourage cell growth. The media’s hormones triggered growth without directing cells to form roots or shoots. Cells continuously divide and form a callus, which is a cluster of undifferentiated plant cells that do not yet have specialized structures. They then transferred the callus blobs to a shaking incubator containing fresh nutrient medium to disperse and promote further cell division, forming a suspension rich in plant cells.
Over 16 weeks, this incubation period of maintaining cells at optimal temperature and conditions was carefully monitored to prevent contamination or cell death.
This setup paved the way for a direct comparison: Do lab-grown trees truly outperform their natural counterparts?
After this multiplication process, researchers compared lab-grown and natural leaf extracts. Both were extracted with methanol. Results showed that plant tissue culture enhanced phytochemical production. Callus extracts contained twice the flavonoids and up to 1.5 times more coumarins than the natural leaves. Callus also produced unique tannins and higher concentrations of 1,8-cineole, α-terpineol, and sabinene.
Volatile oils, which are easily evaporated aromatic compounds, were also extracted from both the leaf and callus samples. During distillation (a process that separates components based on differences in volatility), researchers heated the samples to cause the oils to evaporate and then condense. These oils are known for their anti-inflammatory, antioxidant, and antimicrobial activities. In this study, the callus extract oils yielded higher amounts of volatile oils than the natural leaf extracts.
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Promising effects on human cells
The researchers tested the effects of the extract on human lung cells in an induced inflammatory state. Adding 200 µg/ml of cultured callus methanol extract inhibited TNF-α and IL-6 markers most, suggesting that as little as 2–20 mg of extract may deliver health benefits.
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The future of plant tissue culture
This study demonstrates the value of cultured callus suspensions in elucidating the potential of plant tissues. Future research should incorporate robust statistical methods, improved optimization of plant growth regulators, and comprehensive toxicological assessments. Leveraging established scientific frameworks is essential to maximize the benefits of natural resources, particularly as the demand for novel therapeutics increases. This approach offers a pathway toward more efficient and sustainable utilization of plant-based compounds in the context of rapidly advancing drug discovery.
This study was published in the peer-reviewed journal Scientific Reports.
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Reference
Mahrous, M. H., Nassar, A. M. K., EL-Fiky, F. K., Hammoda, H. M., & El-Hawiet, A. (2026). Enhancing anti-inflammatory activity of Eucalyptus camaldulensis by upregulating secondary metabolites using suspension cultures techniques. Scientific Reports, 16, 4090. https://doi.org/10.1038/s41598-025-34963-8
Featured image: River Red Gum Trees, Alice Springs Desert Park, Alice Springs, Northern Territory, Australia, 2019 by Terry Feuerborn on Flickr, licensed under CC BY-NC 2.0.
About the Author
Nigel Chimbetete has a PhD in Food Science, specializing in Nutritional Biochemistry and Food Product Development. He is passionate about all topics surrounding Food Biochemistry & Food Sustainability. Outside of the lab, Nigel enjoys spending time with his family, cooking, travelling, and playing five-a-side soccer with his local community. Connect with him through @ChimbesHealth on X and on Instagram @dr.chimbeshealth.
The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.
