Pharmacy

1. ANTIMICROBIAL PRESERVATIVES
Presented By:
Mohite Swapnali Atmaram
M.Pharm I (Pharmaceutics)
Rajarambapu College Of Pharmacy,
Kasegaon
1/23/2019
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2. CONTENTS
 Benefits of synthetic preservatives
 Drawbacks of synthetic preservatives
 Benefits of natural preservatives
 Drawbacks of natural preservatives
 Factors affecting preservatives efficacy
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3. BENEFITS OF SYNTHETIC PRESERVATIVES
 Broad-spectrum of activity against bacteria and fungi.
 Many options are available.
 Produced by established chemical manufacturing firms
that understand a great deal about the chemicals.
 Cosistent from batch to batch.
 Relatively low cost.
 Safety/toxicity profiles well understood.
 Compatibility with other cosmetic and personal care
product ingredients is well understood.
 Low concentrations required to effectively preserve
products. Generally do not interfere with fragrance,
lather, color, or other aspects of a given formulation.
 Companies that produce synthetic preservatives often
have in-house microbiology testing laboratories and can
offer fee-based support to cosmetics formulators.
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4. DRAWBACKS OF SYNTHETIC PRESERVATIVES
 Many have developed negative reputations in popular media related
to cosmetics.
 Often petroleum based.
 Some cosumers find them irritating to the skin.
 Interfere with "natural" and "organic" product labeling.
 May require a narrow pH range to be effective.
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5. BENEFITS OF NATURAL PRESERVATIVES
 Allow "natural" and sometimes "organic" product
labeling.
 Consumers generally prefer natural preservatives over
synthetic preservatives.
 Often function over a broad pH range.
 Many confer natural fragrances to products.
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6. DRAWBACKS OF NATURAL PRESERVATIVES
 Fewer options available.
 Often do not inhibit microbial growth as well as synthetic
counterparts.
 Often lack broad-spectrum activity. For example, a natural
preservative may inhibit the growth of Staphylococcus aureus or
"Staph" in a formulation, but may have no mold-inhibiting effect.
 May require relatively high concentrations in formulations to be
effective.
 Often have undesirable impact to other aspects of formulations, such
as color, fragrance, or lather.
 May result in skin sensitization (immunological reaction to the
natural preservative that increases over time.
 Consistency and potency may vary considerably from batch to batch.
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7. FACTORS AFFECTING PRESERVATIVES
EFFICACY
1. Interaction with formulation components
2. Properties of preservatives
3. Effect of containers
4. Types of micro-organisms
5. Influence of pH
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8. 1. INTERACTION WITH FORMULATION
COMPONENTS
 Hydrocollids such as preservatives and diminish methylcellulose,
alignates, tragacanth can interacts with their activity.
 Many emulgents are used in pharmaceutical preparations to
produce elegant applications. Interaction may occur between
preservatives and emulsified oil phase and with emulgent molecules.
 Nature of oil, oil water ratio, type of concentration of emulgent,
influence the concentration of preservatives needed to protect the
system.
 Many tablet additives cause problems in tablet preservations due to
their interaction with added preservatives.
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9. 2.PROPERTIES OF PRESERVATIVES
 The distribution of preservative must be homogeneous and
more solubility in the bulk phase is preferable in multi phase
system.
 Some chemicals such as chlorobutol may hydrolyse on
storage if the pH is unfavourable.
 Preservatives may react with substances leached from the
container and lose its antimicrobial activity
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10. 3.EFFECT OF CONTAINERS
 Formulations packed in glass containers can be expected to
retain their preservative content if closure is airtight.
 Preservatives may penetrate through the plastic container and
interacts with it.
 Rubber also reacts with many preservatives but is still used
for closures.
 Containers or closures may cause contamination of pathogens.
 Screw–capped containers and corks are the common source of
mould spores.
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11. 4.TYPES OF MICRO-ORGANISMS
 Plants products may contain pathogenic microorganisms from the
soil. E.g. Clostridium species, Bacillus anthracis. These soil
microorganisms can cause spoilage of pharmaceutical products.
 Many products prepared from animal sources may contain
pathogens like Salmonella typhi.
 Spores of tetanus and gas gangrene have been isolated from
gelatin.
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12. 5.INFLUENCE OF PH
 Adjustment of the pH of solution may affect the chemical
stability and the activity of the preservative.
 The majority of preservatives are less dependent upon pH,
although cationic active quaternary ammonium compounds
are more active at high pH values.
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