German infectious disease, virologist, and microbiologist research specialists led by Albert Krawczyk, Ph.D. from University of Essen’s West German Centre of Infectious Diseases as well as University Hospital Essen’s Institute for Virology and team sought to investigate if herbal medicines with known antiviral properties had any meaningful impact on SARS-CoV-2, the virus behind COVID-19. One such target is turmeric root, used by Asian societies for cooking as well as in herbal medicine for thousands of years. It turns out the herb’s bioactive ingredient called curcumin exhibits a broad-spectrum antimicrobial activity according to the German scientists. In a recent study, the team tested the antiviral activities of “aqueous turmeric root extract, the dissolved content of a curcumin-containing nutritional supplement capsule, and pure curcumin against SARS-CoV-2.” The author’s recap that in a series of the early state, preclinical lab experiments using cell cultures (VERO E6 and human Calu-3) supernatants, turmeric root extract, dissolved turmeric capsule content, as well as pure curcumin successfully neutralize the novel coronavirus SARS-CoV-2 at subtoxic levels.
Pedigreed German Research Institutes
The German researchers represent prominent institutions including the University of Essen School of Medicine, the University Hospital Essen, Institute of Virology, Ruhr University Bochum, Department of Molecular and Medical Virology, School of Medicine as well as the Department of Molecular Biochemistry, Cell Signaling, and the University Hospital, LMU Munich’s Institute of Psychiatric Phenomics and Genomics (IPPG).
What follows is a brief description of the herb, its history, and use followed by a summary of the study and findings.
Turmeric Root Background
Used for thousands of years as a complementary treatment of several diseases, its bioactive ingredients were first studied in the early 19th century. For example, by 1815 according to the authors, scientists such as Vogel and Pelletier isolated the turmeric root and identified the bioactive ingredient curcumin.
Known as Curcuma longa, the herb Turmeric root is broadly used as a spice in Southeast Asia where it also happens to be broadly cultivated. Of note, the rhizome of Curcuma longa consists of several structurally related curcuminoids. The authors shared that anywhere from 60% to 75% of the curcuminoid content is made of up curcumin which also goes by the name diferuloylmethane. The authors share that the remaining fraction includes combinations of diferuloylmethane (20-25%) and bisdemethoxycurcumin (5-15%).
In reviewing the herb’s properties, the authors refer to a number of studies indicating a broad spectrum of bioactivities including antioxidant, anti-inflammatory, antibacterial, antitumor, and hepatoprotective activities.
Turmeric & SARS-CoV-2 Research Cases
Several research teams have studied the use of turmeric as a possible agent to inhibit SARS-CoV-2. Recently, Brazilian researchers investigated the use of turmeric as an inhibiting force against the novel coronavirus. They looked to determine if the ingredient curcumin could potentially represent a new adjuvant therapy for COVID-19 therapy. Published in the peer review Frontiers in Pharmacology the researchers studied how the agent could “interfere at different times/points during the infection caused by SARS-CoV-2.”
Indian researchers have also investigated the use of curcumin as a possible adjuvant therapy targeting SARS-CoV-2. In a recently published piece in Frontiers of Pharmacology research scientists from a handful of medical centers in India provided information in the article “Oral Curcumin With Piperine as Adjuvant Therapy for the Treatment of COVID-19: A Randomized Clinical Trial.”
For the randomized controlled trial, a 30-bed dedicated COVID-Health Center (DCHC) in Maharashtra served as the participating trial site center. The study protocol called for two groups including 1) a study group of patients that received curcumin (525 mg) with piperine (2.5 mg) in a tablet form twice a day and 2) a control group that received a dose of probiotics twice a day.
The study team reported in the peer review journal that “patients with mild to moderate, and severe symptoms who received curcumin/piperine treatment showed early symptomatic recovery” meaning COVID-19 symptoms such as fever, cough, sore throat breathlessness were reduced faster.
The study team also found that participants in the study group generally fared better with “Less deterioration, fewer red flag signs, better ability to maintain oxygen saturation above 94% on room air, and better clinical outcomes compared to patients of the control group.” They also found that the study drug reduced the duration of hospitalization.
German Preclinical Study Team Findings
The German study team found that the turmeric compounds “effectively neutralized SARS-CoV-2 at subtoxic concentrations in Vero E6 and human Calu-3 cells.”
Additionally, the preclinical, early-stage lab research provides some evidence that “curcumin treatment significantly reduced SARS-CoV-2 RNA levels in cell culture supernatants.” Contributing to an accumulating trove of data, the German team indicates that curcumin represents a “promising compound for complementary COVID-19 treatment.”
Assuming randomized controlled trials replicate and verify the findings the authors post that an adjuvant therapy represents a compelling opportunity to help care for patients infected with SARS-CoV-2, particularly the mild-to-moderate home care cases—represents the vast majority (90%+) of cases.
Lead Research/Investigator
Albert Krawczyk, Ph.D. University of Essen’s West German Centre of Infectious Diseases as well as University Hospital Essen, Institute for Virology, Corresponding Author
Call to Action: The authors recommend the design of randomized controlled trials to “vigorously test the effectiveness of complementary treatment of COVID-19 patients with curcumin-containing products.” Follow the link to read the entire study in the peer review Swiss journal MDPI.