Anti-microbial action

Schroten, H. (2001). Chemistry of milk mucins and their anti-microbial action. Adv. Nutr. Res. 10, 231-245. 

Table 7.18 Anti-microbial action of paper samples on some microorganisms ... 

Anthramycin 4.43) which readily undergoes covalent hydration (Section 2.5, p. 47), inhibits the synthesis of RNA by binding to the DNA template in RNA polymerase, which could account for its anti-tumour and anti-microbial action (Horwitz and Grollman, 1968 Kohn and Spears, 1970). 

The mode of action of acidifier in poultry is mainly due to its anti microbial action, unlike in pigs where a key activity is the reduction of the stomaeh-pH. The effect of acids on gram-negative bacteria is increased if the organie aeid is not dissociated. Because of this mode of action, effective acidifiers need to contain organic acids that are undissociated at different pH-values, so that the antimicrobial action is prolonged over a wider pH range. 

Essential nutrient elements snch as Cu, Fe and Mn can be successfully incorporated into slowly soluble phosphate glass pellets, and fed to ruminant animals (Section 12.9). The glass pellet stays lodged in the rumen for several months where it supplies the nutrient elements [12]. Phospholipids are incorporated in some formnlations to improve animal metabolism. Phosphorus compounds are sometimes added to commercial prodncts for anti-microbial action or to increase their stability. Grains and seeds generally contain more P than hays and grasses, but in the former case much is present as phytic acid salts which are not easily nutritionally available. In some cases appropriate enzymes can be added to rectify this. 

There have been numerous investigations of the effects of small quantities of added phosphates on the processing and final characteristics of cheese. Some phosphates will reduce the rennet coagulation time, increase the yield of curd or improve the flavour of the cheese. Anti-microbial action may also be achieved. 

There is conflicting evidence re the anti-microbial action of phosphates in meats. Effects seem to be variable and depend not only on the type of phosphate used, but also on the processing conditions and other additives used, for example, sodium nitrite or sodium chloride. Under some circumstances, phosphates can successfully replace sodium chloride, when it is desirable to reduce the content of the latter [48-51]. 

Non-ionic surfactants. The addition of fatty acid monoethanolamides, fatty alcohol ethoxylates and alkylpo-lyglycosides (APG) improves skin compatibility and foaming properties of cleansing products, in particular APGs. However, these non-ionic surfactants provide no recognisable anti-microbial action. 

Deodorants are substances that reduce or mask unpleasant body odours whereas antiperspirants reduce body transpiration. Deodorants are classified as over-the-counter (OTC) cosmetics by the U.S. Food and Drug Administration (FDA) whereas the EU considers them as cosmetics. They are composed of substances that inhibit the growth of microorganisms which cause bad odour. They can be formulated either with substances with anti-microbial action (such as ethanol, quaternary ammonium, triclosan) or actives which neutralize the body odour (such as Zn ricinoleate that forms complexes with the sweat). They also often contain essential oils that mask the odour of perspiration. 

Figure 4 Carajurone (R=CHs) and the related carajuretin (R=H) result by the very rapid enzymatic aerial oxidation of flavans present in the leaves of Arrabidaea chica. The plant is one of the most used Amazonian medicinal plants and the anti-microbial and other activities may be related to the presence of these red pigment. Some indigenous tribes use them as face paints and carajurone has been commercialised in the past as chica red. Genipa americana fruit juice, by the action of an endogenous glucosidase followed by aerial oxidation, provides another pigment. The juice has multiple medicinal uses probably associated with its antimicrobial action. Here the dye is blue-black and is believed to be an ethylene-bis- -aza-azulene , derived by condensation of the genipin monomer with primary amines. ...

Oral antimicrobial agents sometimes have beneficial effects in inflammatory bowel disease. However, in the absence of any evidence pointing toward a definite microbial cause for the colitis in this patient, a drug that decreases inflammation is indicated. Sulfasalazine has significant anti-inflammatory action, and its oral use results in symptomatic improvement in 50-75% of patients. The drug is also used for its anti-inflammatory effects in rheumatoid arthritis. The answer is (D). 

Those products that have good biocidal action against these microorganisms can be considered effective. Yet, surprisingly, many manufacturers of over-the-counter (OTC) formulations do not have documented evidence of effectiveness from in vitro studies [time-kill and minimum inhibitory concentration (MIC)] to support their label claims for preoperative skin preps. In vivo studies performed on human volunteers are designed to assure that the products are anti-microbially effective within 10 minutes of application and are antimicrobially persistent for up to 6 hours postapplication. 

Because DNA topoisomerases play key roles in cellular processes affecting the topology and organization of intracellular DNA, it is important to define the physiological functions and understand the molecular basis of their action. Moreover, beyond their normal ceUular activities, these enzymes are proven molecular targets for clinically usefiil anti-tumor " and anti-microbial drugs. In this context work on topoisomerases from the parasites has been a growing focus of interest. 

To stimulate the replacement of more hazardous materials by lignin-derived products biocides and bio-stabilizers in textiles, cosmetics, animal feed (hygienic prevention in food chain) and health prevention by action of lignin as polyphe-nolic compound with specific characteristics like anti-microbial, anti-oxidant etc. 

Nitroimidazoles were then found to have excellent anti-microbial properties. For example, tinidazole (6.16) is valued for the prophylaxis of anaerobic bacteria] infection of the bowel, before operation, particularly with species of Bacteroides, also for the treatment of such infections (Hunt et al., 1979). It is also effective in the protozoal diseases, amoebiasis, giardiasis, and trichomoniasis. For the anti-protozoaI action ofnitro-heterocycles, see Section 6.3.3. 

Table 13.11 Anti microbial Properties and Mechanism of Action of Metal-Based Nanoparticles (Bhattacharya and Mukherjee, 2008 Gutierrez et al., 2010 Russell and Hugo, 1994)...

Acidifiers used in feed have two modes of action. The first one is reduction of pH in the digestive tract, while the second is the direct anti-microbial effect against gram-negative bacteria like E. coli. 

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