The recent coronavirus disease (COVID-19) outbreak in Wuhan, China, has led to millions of infections and the death of approximately one million people. No targeted therapeutics are currently available, and only a few efficient treatment options are accessible. Many researchers are investigating active compounds from natural plant sources that may inhibit COVID-19 proliferation. Flavonoids are generally present in our diet, as well as traditional medicines and are effective against various diseases. Thus, here, we reviewed the potential of flavonoids against crucial proteins involved in the coronavirus infectious cycle. The fundamentals of coronaviruses, the structures of SARS-CoV-2, and the mechanism of its entry into the host’s body have also been discussed. In silico studies have been successfully employed to study the interaction of flavonoids against COVID-19 M^pro, spike protein PL^pro, and other interactive sites for its possible inhibition. Recent studies showed that many flavonoids such as hesperidin, amentoflavone, rutin, diosmin, apiin, and many other flavonoids have a higher affinity with M^pro and lower binding energy than currently used drugs such as hydroxylchloroquine, nelfinavir, ritonavir, and lopinavir. Thus, these compounds can be developed as specific therapeutic agents against COVID-19, but need further in vitro and in vivo studies to validate these compounds and pave the way for drug discovery.

In this study, Kodo millet grains were roasted in the microwave at 360, 720, and 900 W for 3 and 5 min and pan‐roasted at 195°C for 5 min. The Kodo millet flours (KMFs) were characterized on the basis of physical, functional, pasting, rheological, antioxidant, morphological, and structural properties. After roasting, the bulk density (BD) of all treated samples decreased, while the tap density, Hausner’s ratio, and compressibility index (CI) increased with roasting. Higher microwave power (720 and 900 W) and duration time (5 min) resulted in lower L∗ values and higher a∗ and b∗ values. The roasting in pan and microwave significantly improved the water absorption capacity (WAC) of flour. However, the destruction of hydrophobic functional groups resulted in a significant reduction in the oil absorption capacity (OAC). The pasting and rheological curves confirmed that low power can improve the pasting properties, producing thick pastes. However, the pan and microwave roasting (MWR) at 900 W for 5 min degraded starch and resulted in a flat pasting curve. Scanning electron microscope (SEM) micrographs also confirmed this, showing pore space formation, initiated at a power of 720 W and becoming more noticeable until 900 W, when the structure is destroyed. The X‐ray diffraction (XRD) patterns of all samples suggested a type A crystalline structure, and the degree of crystallinity increased with microwave power, except for the 900 W for 5 min and the pan‐roasted KMF. The antioxidant activity (AOA) of all roasted samples was higher than that of the control sample, except for 900 W for 5 min. Total flavonoid content (TFC) decreased in all KMF compared to the control, except 360 W for 3 min. Furthermore, all microwave‐roasted KMF showed significantly higher total phenolic content (TPC) than control and pan‐roasted KMF. These findings provide valuable information on optimizing the roasting process to improve the nutritional and functional properties of KMF.

The functional and structural properties of kodo millet starch were investigated as a function of the degree of substitution during esterification with 2-octenyl-succinic anhydride (OSA) at three concentrations (0%, 1.0%, 2.0% and 3.0%). The increasing degree of substitution (0.0058 to 0.0077) indicates preferential substitution of OS groups in the amorphous region of starch. X-ray diffraction revealed a slight decrease in relative crystallinity (31.37-29.87%), indicating that esterification induced structural modifications in both amorphous and crystalline domains. Fourier transform infrared spectroscopy detected peaks around 1720 cm–1 and 1645 cm–1, confirming OS group substitution. Microscopic analysis revealed particles with increased surface roughness, indicating that esterification occurs at the surface. The amphiphilic nature of OSA contributes to improved oil-binding capacity, swelling and solubility at increasing temperatures (60 ºC, 75 ºC and 90 ºC). However, water-binding capacity did not change significantly. Pasting properties showed an increase in peak viscosity reflecting improved granule swelling behaviour. The shear-thinning and viscoelastic behaviour observed through rheological assessments indicates that esterification effectively improves the functional performance of kodo millet starch, making it a promising ingredient for diverse food formulation applications.