The growth, adventitious bud formation, bioactive flavonoid production, antioxidant response, and cryptochrome-mediated light signal transduction in Isatis tinctoria L. hairy root cultures exposed to LED lights

The root of Isatis tinctoria L. is highly appreciated as a Traditional Chinese herbal medicine for the prevention and adjuvant treatment of respiratory diseases caused by coronaviruses viruses such as SARS and COVID-19. I. tinctoria hairy root cultures (ITHRCs) provide a better alternative to field cultivation for the production of antiviral flavonoids. For the first time, ITHRCs were exposed to different colors of LED lights i.e., red, green, blue, red/green/blue (1/1/1, RGB), and white, in an attempt to promote the root growth and enhance the production of bioactive flavonoids. Results revealed that the biomass productivity (7.15 ± 0.63 g/L) in ITHRCs with an initial inoculum size of 0.2% cultured for 50 days under blue light increased by 1.86-fold relative to that under dark (control), and yields of rutin (320.49 ± 27.56 μg/g DW), quercetin (388.75 ± 9.17 μg/g DW), kaempferol (787.90 ± 83.43 μg/g DW), and isorhamnetin (269.11 ± 20.08 μg/g DW) increased by 4.15-fold, 9.31-fold, 9.09-fold, and 2.88-fold as compared with control, respectively. Interestingly, the emergence of adventitious buds was noticed in ITHRCs under all light treatments. Additionally, the enhanced densities of chloroplasts and root hairs were found in blue-light grown ITHRCs as against control, which might account for the elevated biomass productivity. Moreover, blue light induced oxidative stress in ITHRCs in terms of the overproduction of oxidation products and the enhancement of antioxidant enzyme activity. Furthermore, blue light significantly activated photoreceptor (CRY1) and key regulator of light signaling (HY5), thus leading to the up-regulated expression of MYB4 and structural genes (such as CHS and FLS) responsible for flavonoid biosynthesis. And, the transcriptional activation of CUC1 was likely related to the formation of adventitious buds in ITHRCs. Overall, the simple supplementation of blue LED light makes ITHRCs more attractive as plant factories for obtaining higher productivity of biomass and medicinally important flavonoids. © 2023 Elsevier B.V.

Traditional Chinese herbal medicine at the forefront battle against COVID-19: Clinical experience and scientific basis.

BACKGROUND: Throughout the 5000-year history of China, more than 300 epidemics were recorded. Traditional Chinese herbal medicine (TCM) has been used effectively to combat each of these epidemics' infections, and saved many lives. To date, there are hundreds of herbal TCM formulae developed for the purpose of prevention and treatment during epidemic infections. When COVID-19 ravaged the Wuhan district in China in early January 2020, without a deep understanding about the nature of COVID-19, patients admitted to the TCM Hospital in Wuhan were immediately treated with TCM and reported later with >90% efficacy. APPROACH: We conducted conduct a systematic survey of various TCM herbal preparations used in Wuhan and to review their efficacy, according to the published clinical data; and, secondly, to find the most popular herbs used in these preparations and look into the opportunity of future research in the isolation and identification of bioactive natural products for fighting COVID-19. RESULTS: Although bioactive natural products in these herbal preparations may have direct antiviral activities, TCM employed for fighting epidemic infections was primarily based on the TCM theory of restoring the balance of the human immune system, thereby defeating the viral infection indirectly. In addition, certain TCM teachings relevant to the meridian system deserve better attention. For instance, many TCM herbal preparations target the lung meridian, which connects the lung and large intestine. This interconnection between the lung, including the upper respiratory system, and the intestine, may explain why certain TCM formulae showed excellent relief of lung congestion and diarrhea, two characteristics of COVID-19 infection. CONCLUSION: There is good reason for us to learn from ancient wisdom and accumulated clinical experience, in combination with cutting edge science and technologies, to fight with the devastating COVID-19 pandemic now and emerging new coronaviruses in the future.

Saxifraga spinulosa-Derived Components Rapidly Inactivate Multiple Viruses Including SARS-CoV-2.

Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus (IAV), and norovirus (NV) are highly contagious pathogens that threaten human health. Here we focused on the antiviral potential of the medicinal herb, Saxifraga spinulosa (SS). Water-soluble extracts of SS were prepared, and their virus-inactivating activity was evaluated against the human virus pathogens SARS-CoV-2 and IAV; we also examined virucidal activity against feline calicivirus and murine norovirus, which are surrogates for human NV. Among our findings, we found that SS-derived gallocatechin gallate compounds were capable of inactivating all viruses tested. Interestingly, a pyrogallol-enriched fraction (Fr 1C) inactivated all viruses more rapidly and effectively than did any of the component compounds used alone. We found that 25 µg/mL of Fr 1C inactivated >99.6% of SARS-CoV-2 within 10 s (reduction of ≥2.33 log10 TCID50/mL). Fr 1C resulted in the disruption of viral genomes and proteins as determined by gel electrophoresis, electron microscopy, and reverse transcription-PCR. Taken together, our results reveal the potential of Fr 1C for development as a novel antiviral disinfectant.