Pharmaceutical products preservation with antimicrobial

Potassium benzoate is predominantly used as an antimicrobial preservative in a wide range of beverages, foods and some pharmaceutical formulations. Preservative efficacy increases with decreasing pH it is most effective at pH 4.5 or below. However, at low pH undissociated benzoic acid may produce a slight though discernible taste in food products. 

Benzyl alcohol is listed in the EC positive list of preservatives for cosmetic products (maximum concentration for application 10.000 mg/litre) as a preservative it may be useful also in pharmaceutical preparations. Percentage of use in US cosmetic formulations 0.32%. The activity of benzyl alcohol is not very much affected by the pH and the composition of the medium to be protected. As an auxiliary solvent with antimicrobial efficacy benzyl alcohol is used in preservative compositions for industrial fluids (Paulus et al., 1970a). A well-known preservative for cosmetics and industrial fluids is benzyl alcohol mono(poly)hemiformal (Paulus, 1976) which is a formaldehyde releasing compound and therefore listed under 3.1.2. 

As an oxidizing agent sodium iodate disposes of a broad spectrum of antimicrobial efficacy. Since its oxidizing power is by far not as strong as that of chlorates it may be used as a preservative for cosmetic and pharmaceutical products. In the EEC Cosmetics Directive it is listed among the preservatives allowed for use in cosmetics with a maximum concentration of 0.1% for rinse-off products only. Other application Antiseptic for mucous membranes. 

Methylparaben is widely used as an antimicrobial preservative in cosmetics, food products, and pharmaceutical formulations see Table I. It may be used either alone or in combination with other parabens or with other antimicrobial agents. In cosmetics, methylparaben is the most frequently used antimicrobial preservative. ... 

Comments cationic emulsifying wax is claimed to be of particular value in cosmetic and pharmaceutical formulations when cationic characteristics are important. Thus it can be used in medicated creams, germicidal creams, ointments and lotions, hair conditioners, baby creams, and skin care products in which cationic compounds are included. Cationic emulsifying wax is compatible with cationic and nonionic materials, but is incompatible with anionic surfactants and drugs. Additional antimicrobial preservatives should be included in creams. Cetrimide may cause irritation to the eye see Cetrimide. 

By far, the most widely used antimicrobial preservative used in ophthalmics is BKC (70 percent of all commercial products). It is often used in combination with disodium ede-tate because of the synergistic effects, allowing lower concentrations of BKC to be used. Even the use of BKC has been questioned because of some evidence of eye toxicity in rabbits (Dormans and van Logten 1982), and some people have developed hypersensitivity to this preservative. However, BKC does possess good pharmaceutical properties, being stable in solution, stable to autoclaving, and at the usual concentration of 0.01 percent, is an effective preservative over the range of pH values typically used in ophthalmic formulations. 

Lysozyme is a good example of an enzyme that catalyzes chemical reactions in the cell. Lysozyme acts to kill bacteria by cleaving the covalent bond between the alternating polysaccharides that compose peptidoglycan in bacterial cell walls. The human salivary defense proteins and lysozyme are known to exert a wide antimicrobial activity against a number of bacterial, viral, and fungal pathogens in vitro. Therefore, these proteins, alone or in combinations, have been incorporated as preservatives in foods and pharmaceuticals as well as in oral health care products to restore saliva s own antimicrobial capacity in patients with dry mouth. These antimicrobials used in oral health... 

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