Antimicrobial durability of air filters coated with airborne Sophora flavescens nanoparticles

Research Progress of Traditional Chinese Medicine in Treatment of Myocardial fibrosis

Effective drugs for the treatment of myocardial fibrosis (MF) are lacking. Traditional Chinese medicine (TCM) has garnered increasing attention in recent years for the prevention and treatment of myocardial fibrosis. This Article describes the pathogenesis of myocardial fibrosis from the modern medicine, along with the research progress. Reports suggest that Chinese medicine may play a role in ameliorating myocardial fibrosis through different regulatory mechanisms such as reduction of inflammatory reaction and oxidative stress, inhibition of cardiac fibroblast activation, reduction in extracellular matrix, renin-angiotensin-aldosterone system regulation, transforming growth Factor-β1 (TGF-β1) expression downregulation, TGF-β1/Smad signalling pathway regulation, and microRNA expression regulation. Therefore, traditional Chinese medicine serves as a valuable source of candidate drugs for exploration of the mechanism of occurrence and development, along with clinical prevention and treatment of MF.

Airborne pathogenic microorganisms and air cleaning technology development: A review

Transmission of pathogens through air is a critical pathway for the spread of airborne diseases, as airborne pathogenic microorganisms cause several harmful infections. This review summarizes the occurrence, transmission, and adverse impacts of airborne pathogenic microorganisms that spread over large distances via bioaerosols. Air cleaning technologies have demonstrated great potential to prevent and reduce the spread of airborne diseases. The recent advances in air cleaning technologies are summarized on the basis of their advantages, disadvantages, and adverse health effects with regard to the inactivation mechanisms. The application scope and energy consumption of different technologies are compared, and the characteristics of air cleaners in the market are discussed. The development of high-efficiency, low-cost, dynamic air cleaning technology is identified as the leading research direction of air cleaning. Furthermore, future research perspectives are discussed and further development of current air cleaning technologies is proposed.

Masks for COVID-19

Sustainable solutions on fabricating and using a face mask to block the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread during this coronavirus pandemic of 2019 (COVID-19) are required as society is directed by the World Health Organization (WHO) toward wearing it, resulting in an increasingly huge demand with over 4 000 000 000 masks used per day globally. Herein, various new mask technologies and advanced materials are reviewed to deal with critical shortages, cross-infection, and secondary transmission risk of masks. A number of countries have used cloth masks and 3D-printed masks as substitutes, whose filtration efficiencies can be improved by using nanofibers or mixing other polymers into them. Since 2020, researchers continue to improve the performance of masks by adding various functionalities, for example using metal nanoparticles and herbal extracts to inactivate pathogens, using graphene to make masks photothermal and superhydrophobic, and using triboelectric nanogenerator (TENG) to prolong mask lifetime. The recent advances in material technology have led to the development of antimicrobial coatings, which are introduced in this review. When incorporated into masks, these advanced materials and technologies can aid in the prevention of secondary transmission of the virus.

Five-Decade Update on Chemopreventive and Other Pharmacological Potential of Kurarinone: a Natural Flavanone

In the present article we present an update on the role of chemoprevention and other pharmacological activities reported on kurarinone, a natural flavanone (from 1970 to 2021). To the best of our knowledge this is the first and exhaustive review of kurarinone. The literature was obtained from different search engine platforms including PubMed. Kurarinone possesses anticancer potential against cervical, lung (non-small and small), hepatic, esophageal, breast, gastric, cervical, and prostate cancer cells. In vivo anticancer potential of kurarinone has been extensively studied in lungs (non-small and small) using experimental xenograft models. In in vitro anticancer studies, kurarinone showed IC₅₀ in the range of 2–62 µM while in vivo efficacy was studied in the range of 20–500 mg/kg body weight of the experimental organism. The phytochemical showed higher selectivity toward cancer cells in comparison to respective normal cells. kurarinone inhibits cell cycle progression in G2/M and Sub-G1 phase in a cancer-specific context. It induces apoptosis in cancer cells by modulating molecular players involved in apoptosis/anti-apoptotic processes such as NF-κB, caspase 3/8/9/12, Bcl2, Bcl-XL, etc. The phytochemical inhibits metastasis in cancer cells by modulating the protein expression of Vimentin, N-cadherin, E-cadherin, MMP2, MMP3, and MMP9. It produces a cytostatic effect by modulating p21, p27, Cyclin D1, and Cyclin A proteins in cancer cells. Kurarinone possesses stress-mediated anticancer activity and modulates STAT3 and Akt pathways. Besides, the literature showed that kurarinone possesses anti-inflammatory, anti-drug resistance, anti-microbial (fungal, yeast, bacteria, and Coronavirus), channel and transporter modulation, neuroprotection, and estrogenic activities as well as tyrosinase/diacylglycerol acyltransferase/glucosidase/aldose reductase/human carboxylesterases 2 inhibitory potential. Kurarinone also showed therapeutic potential in the clinical study. Further, we also discussed the isolation, bioavailability, metabolism, and toxicity of Kurarinone in experimental models.

A superfine glass fibre air filter with rapid response to photocatalytic antibacterial properties under visible light by loading rGO/ZnO

The development of high-performance air filter has become more and more important to public health. However, it has always been very challenging for developing a multifunctional air filter to simultaneously achieve excellent filtration and antibacterial properties. Herein, a versatile air filter was prepared with loading the reduced graphene (rGO) and zinc oxide on the superfine glass fibre (s-GF) with the three-dimensional network structure by in situ sol-gel process followed by calcination, which aims to achieve synergistic high-efficiency air filtration and rapid response to photocatalytic antibacterial properties under visible light. The air filter showed a three-dimensional network structure based on a rGO/ZnO/s-GF multilayer and exhibited the highest catalytic performance by achieving a 95% degradation effect on rhodamine B within 2 h and achieving 100% antibacterial inactivation of the Escherichia coli and Staphylococcus aureus within 4 h under visible light when the weight ratio of rGO in rGO/ZnO is 1.6%. The air filtration efficiency can also be maintained at 99% after loading ZnO and rGO photocatalytic particles. The spectrum of the photoluminescence (PL), UV-Vis diffuse reflectance spectra (DRS) and electron spin resonance (ESR) indicate that the combination of rGO and ZnO on the s-GF can increase the separation of photogenerated carriers and the specific surface area of the air filter, thereby increasing the photocatalytic response and antibacterial properties of the s-GF air filter under visible light in a short time.

Advances in Facemasks during the COVID-19 Pandemic Era

The outbreak of coronavirus disease (COVID-19) has transformed the daily lifestyles of people worldwide. COVID-19 was characterized as a pandemic owing to its global spread, and technologies based on engineered materials that help to reduce the spread of infections have been reported. Nanotechnology present in materials with enhanced physicochemical properties and versatile chemical functionalization offer numerous ways to combat the disease. Facemasks are a reliable preventive measure, although they are not 100% effective against viral infections. Nonwoven materials, which are the key components of masks, act as barriers to the virus through filtration. However, there is a high chance of cross-infection because the used mask lacks virucidal properties and can become an additional source of infection. The combination of antiviral and filtration properties enhances the durability and reliability of masks, thereby reducing the likelihood of cross-infection. In this review, we focus on masks, from the manufacturing stage to practical applications, and their abilities to combat COVID-19. Herein, we discuss the impacts of masks on the environment, while considering safe industrial production in the future. Furthermore, we discuss available options for future research directions that do not negatively impact the environment.

Face Masks in the New COVID-19 Normal: Materials, Testing, and Perspectives

The increasing prevalence of infectious diseases in recent decades has posed a serious threat to public health. Routes of transmission differ, but the respiratory droplet or airborne route has the greatest potential to disrupt social intercourse, while being amenable to prevention by the humble face mask. Different types of masks give different levels of protection to the user. The ongoing COVID-19 pandemic has even resulted in a global shortage of face masks and the raw materials that go into them, driving individuals to self-produce masks from household items. At the same time, research has been accelerated towards improving the quality and performance of face masks, e.g., by introducing properties such as antimicrobial activity and superhydrophobicity. This review will cover mask-wearing from the public health perspective, the technical details of commercial and home-made masks, and recent advances in mask engineering, disinfection, and materials and discuss the sustainability of mask-wearing and mask production into the future.

Antimicrobial Air Filters Using Natural Euscaphis japonica Nanoparticles

Controlling bioaerosols has become more important with increasing participation in indoor activities. Treatments using natural-product nanomaterials are a promising technique because of their relatively low toxicity compared to inorganic nanomaterials such as silver nanoparticles or carbon nanotubes. In this study, antimicrobial filters were fabricated from natural Euscaphis japonica nanoparticles, which were produced by nebulizing E. japonica extract. The coated filters were assessed in terms of pressure drop, antimicrobial activity, filtration efficiency, major chemical components, and cytotoxicity. Pressure drop and antimicrobial activity increased as a function of nanoparticle deposition time (590, 855, and 1150 µg/cm2(filter) at 3-, 6-, and 9-min depositions, respectively). In filter tests, the antimicrobial efficacy was greater against Staphylococcus epidermidis than Micrococcus luteus; ~61, ~73, and ~82% of M. luteus cells were inactivated on filters that had been coated for 3, 6, and 9 min, respectively, while the corresponding values were ~78, ~88, and ~94% with S. epidermidis. Although statistically significant differences in filtration performance were not observed between samples as a function of deposition time, the average filtration efficacy was slightly higher for S. epidermidis aerosols (~97%) than for M. luteus aerosols (~95%). High-performance liquid chromatography (HPLC) and electrospray ionization-tandem mass spectrometry (ESI/MS) analyses confirmed that the major chemical compounds in the E. japonica extract were 1(ß)-O-galloyl pedunculagin, quercetin-3-O-glucuronide, and kaempferol-3-O-glucoside. In vitro cytotoxicity and disk diffusion tests showed that E. japonica nanoparticles were less toxic and exhibited stronger antimicrobial activity toward some bacterial strains than a reference soluble nickel compound, which is classified as a human carcinogen. This study provides valuable information for the development of a bioaerosol control system that is environmental friendly and suitable for use in indoor environments.

Development and evaluation of antimicrobial activated carbon fiber filters using Sophora flavescens nanoparticles

Activated carbon fiber (ACF) filters have a wide range of applications, including air purification, dehumidification, and water purification, due to their large specific surface area, high adsorption capacity and rate, and specific surface reactivity. However, when airborne microorganisms such as bacteria and fungi adhere to the carbon substrate, ACF filters can become a source of microbial contamination, and their filter efficacy declines. Antimicrobial treatments are a promising means of preventing ACF bio-contamination. In this study, we demonstrate the use of Sophora flavescens in antimicrobial nanoparticles coated onto ACF filters. The particles were prepared using an aerosol process consisting of nebulization-thermal drying and particle deposition. The extract from S. flavescens is an effective, natural antimicrobial agent that exhibits antibacterial activity against various pathogens. The efficiency of Staphylococcus epidermidis inactivation increased with the concentration of S. flavescens nanoparticles in the ACF filter coating. The gas adsorption efficiency of the coated antimicrobial ACF filters was also evaluated using toluene. The toluene-removal capacity of the ACF filters remained unchanged while the antimicrobial activity was over 90% for some nanoparticle concentrations. Our results provide a scientific basis for controlling both bioaerosol and gaseous pollutants using antimicrobial ACF filters coated with S. flavescens nanoparticles.