Alcohols antimicrobial activity

Povidone—iodine is a brown, water-soluble powder containing approximately 10% iodine. However, the amount of free iodine, which is responsible for the antimicrobial activity, is low in a concentrated solution, but is released as the solution is diluted (41). Concentrated solutions have actually been contaminated with bacteria (42). For use as an antiseptic, povidine—iodine is diluted with water or alcohol to a concentration of 1% iodine. Detergents are added if it is used as a surgical scmb. lodophors are important as broad-spectmm antiseptics for the skin, although they do not have the persistent action of some other antiseptics. They are also used as disinfectants for clinical thermometers that have been used by tuberculous patients, for surface disinfection of tables, etc, and for clean equipment in hospitals, food plants, and dairies, much as chlorine disinfectants are used. 

Alcohols, particularly ethanol [64-17-5] and 2-propanol [67-63-9] are important disinfectants and antiseptics. In the aUphatic series of straight-chain alcohols, the antimicrobial activity increases with increasing molecular weight up to a maximum, depending on the organism tested. For Staphylococcus aureus the maximum activity occurs using amyl alcohol [71-41-0], for Salmonella typhosa, octyl alcohol [111-87-5], CgH gO (43) ioT Mycobacterium tuberculosis... 

Plant Material - The yellow heartwood was separated from the sapwood of JL, tullplfera and air dried before grinding. Other plant parts (leaf, stem bark, root bark, root, fruit, and flower) were collected, but alcoholic extracts showed no antimicrobial activity. 

Extraction and Separation of Alkaloids - The air-dried ground heart-wood (2.2 kg) was extracted by percolation at room temperature with alcohol USP until a negative alkaloid test of the percolate was observed. Removal of the solvent at reduced pressure and at 40° left 71 g of residue that exhibited antimicrobial activity. A 35 g sample of the alcohol-soluble residue was partitioned between 125 ml each of ether and 2Z citric acid In water. The ether layer was extracted twice more with 125 ml of 2% citric acid, filtered to remove some lnterfaclal solids (5.8 g alkaloid negative, no antimicrobial activity), dried (sodium sulfate), and evaporated to dryness, giving 8.6 g of ether solubles that had no antimicrobial activity. 

This aromatic alcohol has been an effective preservative and still is used in several ophthalmic products. Over the years it has proved to be a relatively safe preservative for ophthalmic products [138] and has produced minimal effects in various tests [99,136,139]. In addition to its relatively slower rate of activity, it imposes a number of limitations on the formulation and packaging. It possesses adequate stability when stored at room temperature in an acidic solution, usually about pH 5 or below. If autoclaved for 20-30 minutes at a pH of 5, it will decompose about 30%. The hydrolytic decomposition of chlorobutanol produces hydrochloric acid (HC1), resulting in a decreasing pH as a function of time. As a result, the hydrolysis rate also decreases. Chlorobutanol is generally used at a concentration of 0.5%. Its maximum water solubility is only about 0.7% at room temperature, which may be lowered by active or excipients, and is slow to dissolve. Heat can be used to increase dissolution rate but will also cause some decomposition and loss from sublimation. Concentrations as low as 0.125% have shown antimicrobial activity under the proper conditions. 

Raghavan and coworkers have reported on the preparation of 4-hydroxybenzoic add esters (parabans) possessing antimicrobial activity by esterification of 4-hydroxybenzoic acid (Scheme 6.153) [299]. Optimum results were obtained using the alcohol (1-butanol) as solvent in the presence of catalytic amounts of zinc(II) chloride or p-toluenesulfonic acid (pTsOH) under atmospheric conditions. After 5 min of microwave irradiation at 120 °C, ca. 40% conversion to the ester was observed. Related studies on the synthesis of long-chain aliphatic esters have been described by Mariani and coworkers [300]. 

Furfuryl alcohol is oxidized directly to 2,3-dideoxy-DL-pent-2-eno-pyranosid-4-nlose (325, R = H) by treatment with m-chloroperoxy-benzoie acid.236 A variety of substituted furfuryl alcohols have thus been converted into over 60 enediulose derivatives (345) in connection with studies of their antimicrobial activity.211 It was later found that pyridinium chlorochromate may be applied in this reaction, instead of a peroxy acid.237... 

Two epimeric amino alcohols, 2(5)-aminotetradeca-5,7-dien-3(5)- and -3(/ )-ol (305 and 306) were isolated from a sponge from Papua New Guinea (Xestospongia sp.) (248). The absolute stereochemistry was disclosed by degradation to L-alanine, and these amino alcohols (305 and 306) were suggested to be biosynthesized from fatty acids and alanine. Compounds 305 and 306 show antimicrobial activity. Rhizochalin (307) was isolated from the Madagascan sponge Rhizochalina incrustata as an antimicrobial constituent (349). The biosynthetic pathway for 307 is unknown but is conventionally believed to be derived from alanine and a polyketide precursors). 

The northeast Pacific bryozoans Phidolopora pacifica contained two nitrophenols, desmethylphidolopin (448) and 3-nitro-4-hydroxybenzyl alcohol (449) (365). Desmethylphidolopin (448) showed antimicrobial activity. 2-Amino-6-[(r/ ,2 5)-l, 2 -dihydroxypropyl]-3-methyl pterin-4-one (450) was isolated from the anthozoan Astroides calycularis collected in the Bay of Naples and exhibited cell growth-inhibiting activity (366). The structure of leucettidine, a pteridine derivative found in Leucetta microra-... 

Brandy or alcohol extracts of spices and herbs may be used for flavoring vermouth (Rizzo, 1957). Spices like anola, and ginger are known to possess medicinal properties, as well as antimicrobial activities (Joshi and John, 2002). The precise details of extraction differ among manufactures. The more important botanical constituents include coriander, cloves, chamomile, dittany of Crete, orris, and quassia. Additional flavorant may include allspice, angelica, anise, bitter almond, cinchona, coriander, juniper, nutmeg, orange peel, and rhubarb. 

Antimicrobial activity benzyl alcohol is bacteriostatic and is used as an antimicrobial preservative against Gram-positive bacteria, molds, fungi, and yeasts, although it possesses only modest bactericidal properties. Optimum activity occurs at pH below 5 little activity is shown above pH 8. Antimicrobial activity is reduced in the presence of nonionic surfactants, such as polysorbate 80. However, the reduction in activity is less than is the case with either hydroxybenzo-ate esters or quaternary ammonium compounds. The activity of benzyl alcohol may also be reduced by incompatibilities with some packaging materials, particularly polyethylene see Section 12. 

Isopropyl alcohol has some antimicrobial activity (see Section 10) and a 70% v/v aqueous solution is used as a topical disinfectant. Therapeutically, isopropyl alcohol has been investigated for the treatment of postoperative nausea or vomiting,... 

Antimicrobial activity isopropyl alcohol is bactericidal at concentrations greater than 70% v/v it is a mote effective antibacterial preservative than ethanol (95%). The bactericidal effect of aqueous solutions increases steadily as the concentration approaches 100% v/v. Isopropyl alcohol is ineffective against bacterial spores. 

Incompatible with oxidizing agents and protein, e.g., serum. Phenylethyl alcohol is partially inactivated by polysorbates, although this is not as great as the reduction in antimicrobial activity that occurs with parabens and polysorbates. ... 

Karamenderes et al. [67] reported the composition and antimicrobial activity of the essential oils obtained from Achillea millefolium L. subsp. pannonica (Scheele) Hayek, Achillea millefolium subsp. millefolium, Achillea arithmifolia Waldst Kitt and Achillea kotschyi Boiss. subsp. kotschyi, four Achillea species from Turkey. 1,8-cineole, Fig. (2), artemisia alcohol and ascaridole were identified as major components. The essential oils showed antibacterial and antifungal effects even with low concentrations. The essential oil of the flowering tops of another Achillea species, Achillea fragantissimum (Forsk.) Sch. Bip growing in Sinai, was analyzed [68]. Santolina alcohol, a- and P-thujone, Fig. (5) and artemisia ketone account for approximately 80% of the oil. The oil showed marked antimicrobial activities against Escherichia coli. Bacillus subtilis and Staphylococcus aureus. 

The volatile constituents of Conyza dioscorides L. (Desf.) growing in Egypt showed promising antimicrobial activities against some tested microorganisms [153]. The volatile constituents consisted mainly of sesquiterpene hydrocarbons and oxygenated sesquiterpenes. The major sesquiterpene hydrocarbons are (3-maaliene and a-elemene, while the major oxygenated sesquiterpene compounds are a-cadinol, muurolol, caryophyllene oxide isomers and a sesquiterpene alcohol. 

Extrusion is a cost effective manufacturing process. Extrusion is popularly used in large scale production of food, plastics and composite materials. Most widely used thermoplastics are processed by extrusion method. Many biopolymers and their composite materials with petroleum-based polymers can also be extruded. These include pectin/starch/poly(vinyl alcohol) (Fishman et al. 2004), poly(lactic acid)/sugar beet pulp (Liu et al. 2005c), and starch/poly(hydroxyl ester ether) (Otey et al. 1980), etc. In this study, composite films of pectin, soybean flour protein and an edible synthetic hydrocolloid, poly(ethylene oxide), were extruded using a twin-screw extruder, palletized and then processed into films by compression molding process or blown film extrusion. The films were analyzed for mechanical and structural properties, as well as antimicrobial activity. 

Grayish-white powder Very bitter taste. Sol in water alcohol. Practically insol in ether, chloroform, acetone. Stable in acid soln unstable in alkaline solns. Potency loss probably due to transformation of bacitracin A to bacitracin F, latter having little antimicrobial activity. 

The initial selection of adjuvants to crinitol was based largely on the above mentioned structure-activity relationship study. Thus, the hydroxy group at C-9 in crinitol seems to be essential to its antibacterial activity. The allylic C-9 hydroxy group is easily oxidized, a possibility which might detoxify crinitol in bacterial systems. Because crinitol possesses two allylic alcohol groups in its molecule (at C-1 and C-9), we combined it with several antioxidants which have been used as food and cosmetic additives. Thus two natural antioxidants, vitamins C and E, and two synthetic antioxidants, BHA and BHT, were chosen for the experiment. While the synthetic antioxidants exhibited antimicrobial activity against all the test bacteria (30), natural antioxidants did not show any activity up to 800... 

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