Correction: Javed et al. The Potential Impact of Smog Spell on Humans' Health Amid COVID-19 Rages. Int. J. Environ. Res. Public Health 2021, 18, 11408.

There was an error in the original publication [...].

Biochemical and Immunological implications of Lutein and Zeaxanthin.

Throughout history, nature has been acknowledged for being a primordial source of various bioactive molecules in which human macular carotenoids are gaining significant attention. Among 750 natural carotenoids, lutein, zeaxanthin and their oxidative metabolites are selectively accumulated in the macular region of living beings. Due to their vast applications in food, feed, pharmaceutical and nutraceuticals industries, the global market of lutein and zeaxanthin is continuously expanding but chemical synthesis, extraction and purification of these compounds from their natural repertoire e.g., plants, is somewhat costly and technically challenging. In this regard microbial as well as microalgal carotenoids are considered as an attractive alternative to aforementioned challenges. Through the techniques of genetic engineering and gene-editing tools like CRISPR/Cas9, the overproduction of lutein and zeaxanthin in microorganisms can be achieved but the commercial scale applications of such procedures needs to be done. Moreover, these carotenoids are highly unstable and susceptible to thermal and oxidative degradation. Therefore, esterification of these xanthophylls and microencapsulation with appropriate wall materials can increase their shelf-life and enhance their application in food industry. With their potent antioxidant activities, these carotenoids are emerging as molecules of vital importance in chronic degenerative, malignancies and antiviral diseases. Therefore, more research needs to be done to further expand the applications of lutein and zeaxanthin.

The Potential Impact of Smog Spell on Humans' Health Amid COVID-19 Rages.

Rapid and unchecked industrialization and the combustion of fossil fuels have engendered a state of fear in urban settlements. Smog is a visible form of air pollution that arises due to the over-emissions of some primary pollutants like volatile organic compounds (VOCs), hydrocarbons, SO2, NO, and NO2 which further react in the atmosphere and give rise to toxic and carcinogenic secondary smog components. Smog reduces the visibility on roads and results in road accidents and cancellation of flights. Uptake of primary and secondary pollutants of smog is responsible for several deleterious diseases of which respiratory disorders, cardiovascular dysfunction, neurological disorders, and cancer are discussed here. Children and pregnant women are more prone to the hazards of smog. The worsening menace of smog on one hand and occurrence of pandemic i.e., COVID-19 on the other may increase the mortality rate. But the implementation of lockdown during pandemics has favored the atmosphere in some ways, which will be highlighted in the article. On the whole, the focus of this article will be on the dubious relationship between smog and coronavirus.

Podophyllotoxin: History, Recent Advances and Future Prospects.

Podophyllotoxin, along with its various derivatives and congeners are widely recognized as broad-spectrum pharmacologically active compounds. Etoposide, for instance, is the frontline chemotherapeutic drug used against various cancers due to its superior anticancer activity. It has recently been redeveloped for the purpose of treating cytokine storm in COVID-19 patients. Podophyllotoxin and its naturally occurring congeners have low bioavailability and almost all these initially discovered compounds cause systemic toxicity and development of drug resistance. Moreover, the production of synthetic derivatives that could suffice for the clinical limitations of these naturally occurring compounds is not economically feasible. These challenges demanded continuous devotions towards improving the druggability of these drugs and continue to seek structure-optimization strategies. The discovery of renewable sources including microbial origin for podophyllotoxin is another possible approach. This review focuses on the exigency of innovation and research required in the global R&D and pharmaceutical industry for podophyllotoxin and related compounds based on recent scientific findings and market predictions.