The human body has a fantastic protective mechanism. The immune system is one of humans’ gifts for survival in today’s environment. Despite facing many challenges, such as pandemic outbreaks, natural disasters, and chemical weapons threats, humans are still able to survive with a series of amazing self-protection mechanisms. This adaptability and recovery speed are some of the advantages humans have over other living beings.

The immune system protects the body from pathogens such as bacteria and viruses through two types of immunity: innate and adaptive. Innate immunity is the first defense system that works quickly using white blood cells such as neutrophils, macrophages, and dendritic cells.

“Humans have a good immune system, but if there is a malfunction in the immune system, there will be various disorders, such as myasthenia gravis, type 1 diabetes (T1D), systemic lupus erythematosus, Graves’ disease, celiac disease, pernicious anemia, rheumatoid arthritis, and multiple sclerosis. However, the immune system should not be overactive and should still work naturally. If it is too active, there will be a disorder that we call hypersensitivity,” said a Pharmacy Expert at the Universitas Sumatera Utara (USU), Yuandani, Ph.D.

Many diseases are present due to disturbances in the human immune system, one of which is Crohn’s disease or inflammation of the wall lining of the digestive system. “Crohn’s disease is a disease that attacks the small intestine. It occurs due to a disturbance in the immune system that affects many people,” said Yuandani, Ph.D.

Based on available data, Crohn’s disease affects 1 in 133 people in the United States. While in Asian countries, this disease shows a high increase in risk. Therefore, modulation of immune response is necessary in managing and treating diseases caused by immune system dysfunction. Yuandani, Ph.D., along with other pharmaceutical experts from USU, Ade Sri Rohani and Imam Bagus Sumantri, and Ibrahim Jantan from Universiti Kebangsaan Malaysia, worked together to conduct research related to this.

The treatment of inflammatory diseases and immune disorders involves immunomodulation, which is the process of modifying the immune response with drugs such as prednisone, hydrocortisone, and dexamethasone. However, these drugs often have side effects. Therefore, safer and more effective alternatives are needed, such as natural products that have the potential to be anti-inflammatory agents.

“There are already existing treatments for immune disorders, but they still have many side effects. Therefore, we found one source of potential from plants of the Curcuma genus that can modulate immune function,” explained Yuandani, Ph.D.

Curcuma is one of the largest plants in the Zingiberaceae family, with around 100 species, widely distributed from tropical Asia to Australia. The name “curcuma” comes from the Arabic “kurkum” which means yellow color. The root tissue of this plant is widely used in traditional medicine, spices, dyes, cosmetics, and fragrances. Some well-known species include turmeric (C. longa), temulawak (C. zanthorrhiza), and mango ginger (C. amada).

Plants of the Curcuma genus are known for their phytochemical content and remarkable health benefits. Several studies have found various chemical compounds in these plants, such as terpenoids, flavonoids, and polyphenols. For example, the rhizome of Curcuma longa contains more than 235 compounds, including curcuminoids, most of which are curcumin, as well as various types of terpenoids.

“Currently, the potential of plants from the Curcuma genus is huge as immunomodulators in healing immune system diseases or immune disorders. In addition to its enormous potential, this plant is also very much found around us. In fact, they are often used as kitchen spices such as turmeric, temulawak, ginger, and others,” said Yuandani, Ph.D.

The research found several “miracles” contained in plants that we often find. Curcuma longa, or turmeric, has shown benefits in affecting the immune system in various ways. Turmeric extracts have shown the ability to protect the liver from acute injury and enhance the immune response to infection. The use of turmeric has also been explored to enhance host defenses in fish and chickens, showing increased cellular and humoral activity.

Meanwhile, Curcuma zanthorrhiza, also known as temulawak, positively affects the human immune system. In laboratory studies, its extract has been shown to reduce the formation of free radicals that damage body cells. It also inhibits the release of inflammatory substances from white blood cells and reduces the movement of inflammatory cells. In addition, Curcuma extract can suppress inflammatory reactions under various conditions, such as in mice with a high-cholesterol diet and alcohol hepatitis. Curcuma longa may affect various immune parameters in the human body, although further research is still needed to confirm its overall safety and effectiveness.

The mango ginger plant (Curcuma amada Roxb.) also produces extracts that show potential as immunomodulatory agents. The ethanol extract of ginger increased phagocytic activity by PMN cells and showed the highest stimulation at a concentration of 3 mg/ml. This plant extract increased hypersensitivity responses and antibody titers in specific doses. In particular, supercritical CO2 extracts of Curcuma can be used to treat immune disorders such as allergies and autoimmune diseases. Curcuma longa is also used in combination with other plants to treat allergies.

Meanwhile, the black temu plant (Curcuma aeruginosa) can potentially regulate immune responses. Based on research, its methanol extract showed the ability to inhibit several functions of phagocytic cells, which play an essential role in the body’s defense against infection. In addition, it can also inhibit the production of reactive oxygen (ROS) from PMN cells and macrophages, which helps reduce oxidative stress in the body. Temu Putih or Curcuma zedoaria can modulate the immune system well. Research results show that white temu extract can affect tumor development and immune response in experiments conducted on mice.

Curcuma mangga also positively affects the immune system by reducing the production of compounds that play a role in inflammation. Extracts from this plant, particularly its chloroform, hexane, and ethyl acetate fractions, were shown to inhibit NO from LPS-induced cells. In addition, the methanol extract of Curcuma mangga rhizome showed strong inhibitory activity against oxygen radicals (ROS) in peritoneal cells and macrophages. This extract also showed significant anti-inflammatory and analgesic effects in experimental animals, such as rats. However, the effects may vary depending on the dose, extraction method, and experimental conditions.

“More in-depth research, including complex bioavailability, preclinical pharmacokinetics, and toxicity studies, are needed to understand the underlying mechanisms and safety levels related to the use of Curcuma as an immunomodulator before clinical trials can be conducted for the development of potent and safe immunomodulatory agents,” Yuandani, Ph.D. concluded.

Based on the study results, it was concluded that plants from the genus Curcuma have great potential as immunomodulators in overcoming immune system disorders. Nevertheless, every study on several types of plants has revealed many shortcomings that require further research.