Companies: Particle Measuring Systems
Introduction:
Typical virus inactivation methods include low pH treatment (e.g., below pH 4.5, below 4.0 or even below 3.8, heat treatment, treatment with surfactants and radiation (e.g., ultraviolet light exposure).
Air Filters/cleaners: Ultravation (has an interesting set of products which uses activated carbon and UV to sanitize the air).
UV Products: Xenex (pulsed UV disinfection robots) UVivatec (Bayer)
Biofilm Control Practices;
Biofilm control practices currently exist in the form of sterilization methods such as
ethylene oxide, steam autoclaving, and electron-beam, hydrogen peroxide plasma, and
gamma irradiation. However, these methods can damage thermally and hydrolytically sensitive polymers and metal alloys, diminishing their integrity. More recently, light-emitting diodes (LEDs) have been used as an alternative method for biofilm elimination because illumination at wavelengths in the range of 400 to 450 nm has an antibacterial effect. Although the antibacterial efficacy of LED illumination is lower than that of other methods, lower-energy photons are produced, resulting in less material degradation and minimal human tissue damage. (Shi “Inactivation of Pseudomonas aeruginosa Biofilms by 405-Nanometer-Light-Emitting Diode Illumination” Applied and Environmental Microbiology, 2020)
light-emitting diodes (LEDs) : 405-nm light-emitting diode (LED) illumination has been shown effective in eliminating P. aeruginosa biofilms formed on stainless steel coupons under different temperatures. Results showed that the abundance of planktonic P. aeruginosa cells was reduced by 0.88, 0.53, and 0.85 log CFU/ml following LED treatment for 2 h compared with untreated controls at 4, 10, and 25°C, respectively. For cells in biofilms, significant reductions (1.73, 1.59, and 1.68 log CFU/cm2) were observed following LED illumination for 2 h at 4, 10, and 25°C, respectively. Moreover, illuminated P. aeruginosa biofilm cells were more sensitive to benzalkonium chloride or chlorhexidine than untreated cells. (Shi “Inactivation of Pseudomonas aeruginosa Biofilms by 405-Nanometer-Light-Emitting Diode Illumination” Applied and Environmental Microbiology, 2020)
Chemical Disinfectants:
Oxidation: is used in industry with the production of cleaning products. Substances which have the ability to oxidize other substances are known as oxidative or referred to as oxidizing agents, oxidizers and oxidants. Oxidants remove electrons from other substances. Thus oxidants are themeselves reduced. Examples of oxidants include H2O2, CrO3 and have high oxidation numbers. They are highly electronegative that can gain one or two extra electrons by oxidizing a substance. For more information on oxidation click here.
H2O2 + PAA: The use of chemical disinfectants and, notably, oxidizing agents to sterilize medical devices is increasing. With this in mind, hydrogen peroxide (H2O2) and peracetic acid (PAA) have been used in combination for bacterial spores. Bacterial spores are a highly resistant cell type formed when certain members of the Firmicutes, e.g., Bacillus and Clostridium spp., encounter environmental stress, commonly nutrient starvation. The bacterial spore structure differs markedly from the structure of the vegetative cell, and the differences confer upon the spore remarkable resistance to many environmental stresses, including extremes of temperature, radiation, and chemical assault. Relatively few chemical antimicrobials have genuine sporicidal activity, and those which do are principally among the alkylating and oxidizing agent. Oxidizing agents are widely used for the control of spore-forming organisms, with chlorine-based disinfectants finding particularly widespread use. Two other oxidizing agents, peracetic acid (PAA) and hydrogen peroxide (H2O2), are also sporicidal. It is well cited that PAA and H2O2 in combination (P/H) act synergistically to dramatically improve their bactericidal and sporicidal activities relative to those of either agent used alone. See Leggette
Biosurfactants: are naturally occurring amphiphiles that are being actively pursued as alternative to syntehtic surfactants in cleaning, personal care, and cosmetic products. On the basis of their ability to mobilize and disperse hydrocarbons, biosurfactants are also involved in the bioremediation of oil spills. (Tsianou, “Rhamnolipid Micellizaiton and Adsorption Properites” Int J Mol Sci, 2022).
–Rhamnolipids: are LMW glycolipid biosurfactants that consist of a mono or di-rhamnose head group and a hydrocarbon fatty acid chain.
Bioremediation:
Plastics
Although plastics have been an economic boon, particularly in packaging and construction applications, their use has produced unsustainable levels of waste. From 1950 to 2015, about 4900 megatons, accounting for 59% of all plastics ever produced, have been discarded into landfills and the environment. Ninety percent of plastics produced—consisting of polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polyurethane (PU) and polystyrene (PS) are projected to persist for hundreds of years; they are not biodegradable on timescales relative to their end of use. Consequently, their bioaccumulation poses threats to ecosystems and, potentially, to human health.
Although PE, PP, PVC, PET, PU and PS are referred to as non-biodegradable, some microbes and insects have ways to metabolise these plastics into their constituent molecules. Among the most produced plastics, PET is a hydrolysable polymer that is widely used in the packaging and textile industries. Compared to other common plastics, PET is more amenable to biodegradation due to the presence of hydrolysable ester bonds. Substantial progress has been made in enzymatic PET depolymerisation for resource recovery. For example, PET hydrolase (PETase) from Ideonella sakaiensis has been subject to numerous protein engineering efforts that have resulted in PETase variants with depolymerisation rates orders of magnitude higher than the wild-type enzyme, and with greater thermoand chemostability.
Microbial communities could be supplemented with engineered bacteria that secrete plastic-degrading enzymes (i.e., cell bioaugmentation); this can be more cost-effective than continuously supplementing a cocktail of purified enzymes into a secondary treatment unit. A major challenge with the cell bioaugmentation approach is persistence of the introduced microorganisms, which are often not adapted to the environment at hand and are therefore likely to be quickly eliminated.
As an alternative strategy that would bypass these barriers to establishment, genetically engineering microbes native to the environment to express metabolic pathways for biodegradation of plastic waste. This approach, known as genetic bioaugmentation, can be achieved through in situ delivery of broad-host-range conjugative plasmids. Genetically engineered bacteria in a municipal wastewater sample to degrade PET plastics by delivering a broad-host-range, conjugating plasmid carrying the FAST-PETase gene, which codes for an engineered PET hydrolase that is more robust to pH and temperature ranges and is orders of magnitude more efficient than the wild-type enzyme. See Ingalls
Antibacterial Products; Hand Sanitizers/Soaps:
Antimicrobial Compositions:
–Medium-chain fatty-acids: caprylic acid (C8), capric acid (C10 and Lauric acid (C12):
Long (US 2010/0016430) discloses a modified cocnut oil whcih contains effective amounts of medium chain fatty acids which have antimicrobial properties. The medium chain fatty acids include caprylic acid capric acid and lauric acid.
–Glycerol Monolaurate (GML):
Staphylococcus aureus and Neisseria gonorrheae as well as certain gram negative Enterobacteriacaeae (e.g., Salmonella and E. coli) were reproted relatively resistant to direct toxic effect of GML. However, contact of yeasts and bacteria of a variety of strains with glycerol monolaurant (GML) has been shown to curtail their growth or kill them. Schlievert (US 2006/0029558) discloses a method of treatment or prophylaxis that includes identifying a subject likely to have been or be exposed to an infectious fungal microorganism kor bacterial microorganism and administering a glycerol-based compound (e.g., GML).
Day (US 10,435,654) discloses a soap composition that includes a high laurate saop component with a lipolyzed oil composition that includes an antimicrobial composition that includes glycerol monolaurate. Preferably, the glycerol monolaurate in a concentration of at least about 2 mM and the high laurate soap component includes about 5% by weight of a lauric acid salt.