The global spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has called for an urgent need for the identification of compounds able to control, prevent or slow down the global pandemic. In new research, scientists at the Jacobs University Bremen found that 5-caffeoylquinic acid, a polyphenolic chemical compound found in coffee, reduces the binding constant between SARS-CoV-2’s spike protein and human angiotensin converting enzyme II (ACE2), which is the entry receptor for the virus.
Colorized scanning electron micrograph of a cell infected with the Omicron strain of SARS-CoV-2 virus particles (yellow and green), isolated from a patient sample. Image credit: NIAID.
Coffee is one of the most widely consumed beverages in the world and one of the most traded commodities globally.
From a chemical point of view, it is a rich source of biologically active compounds and its potential human health effects depend on consumers’ physiology and the amount of coffee consumed per day.
Among several compounds present in coffee, chlorogenic acids — such as 5-caffeoylquinic acid (5-CQA) — are one of the most important groups.
“A regular cup of filter coffee — in the laboratory setting it comprises exactly 200 milliliter — contains about 100 milligrams of 5-CQA,” said senior author Professor Nikolai Kuhnert, a researcher in the Department of Life Sciences and Chemistry at the Jacobs University Bremen, and his colleagues.
“Our experiments showed that 5-CQA in this concentration is high enough to prevent the docking of the spike protein to the ACE2 receptor — and therefore also inhibit the infection process.”
Using nano differential scanning fluorimetry, the authors studied the effects of 5-CQA and several other dietary polyphenols on the SARS-CoV-2 S1 spike protein and the human ACE2 receptor.
Their experiments were based on the thermophoresis of a fluorescently labeled spike protein and the ACE2 receptor in the presence of dietary concentrations of the compound in question.
“As chemists, we cannot answer the practical question of whether drinking coffee could really serve as a preventive measure to protect against infection. But we can say it is plausible,” Professor Kuhnert said.
“Many people drink coffee and that it has many other positive effects is well established.”
“Regular coffee drinkers suffer less frequently from type II diabetes, for example, the scientific evidence for this is very good, he points out.”
“Epidemiological studies could determine whether regular coffee drinkers become more often infected with SARS-CoV-2 or not,” he said.
The results were published in the journal Food & Function.
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Dorothea Schmidt et al. 2022. Investigating the interaction between dietary polyphenols, the SARS CoV-2 spike protein and the ACE-2 receptor. Food Funct 13: 8038-8046; doi: 10.1039/D2FO00394E
