in silico screening of Vigna radiata and Vigna mungo phytochemicals for their binding affinity to SARS-CoV-2 (COVID-19) main protease (3CLpro)

The seeds of Vigna radiata (green gram) are a favorite dish in Bangladesh and India and also considered an important nutritional and medicinal food in Ayurveda. According to Ayurveda, the pulse can pacify kapha and pitta but can aggravate vata. The seeds of another pulse, Vigna mungo (black gram) are also widely consumed in India and Bangladesh, more so by the low income groups of population. According to Ayurveda, this pulse is good for pacifying vata. A new coronavirus infection COVID-19 or SARS-CoV-2 have become a pandemic and as of June 28, 2020, have infected 10,080,224 persons and caused 501,262 deaths throughout the world. The statistics for USA, India and Bangladesh are, respectively, 2,596,537 infections and 128,152 deaths, 529,577 infections and 16,103 deaths, and 133,978 infections and 1,695 deaths. The respective populations for these three countries are 328.2 million (2019 figure), 1.353 billion (2018 figure), and 161.4 million (2018 figure). Thus despite the higher poverty level and population density, India and Bangladesh have managed to keep COVID infection levels much lower than an advanced country like USA. Although there can be a number of factors behind low COVID levels in India and Bangladesh, dietary habits may be one of them. The two pulses are taken on a daily basis and more often more than one times per day in India and Bangladesh by all sections of the population. In silico screening of the major phytochemicals of the two pulses revealed that a number of phytochemicals present in the pulses have high binding affinities for the C-3 like main protease of COVID-19, which is vital for viral replication. Although a definite conclusion cannot be reached without doing anti-viral tests, it is plausible that inhibition of the protease by the phytochemicals present in the two pulses may contribute to the low incidences of COVID-19 infections in India and Bangladesh.