This document discusses the isolation and identification of phenol-degrading bacteria. It notes that phenols are toxic compounds found in the environment and produced as pollutants. A large diversity of microorganisms are able to metabolize and degrade many organic pollutants like phenol through enzymatic processes. The document outlines some of the health and environmental risks of phenol, and notes that controlling phenol pollution is important to avoid ecological problems. It also discusses some of the nutritional requirements that allow microbes to degrade phenol aerobically.

1. Isolation and identification of phenol
degrading
bacteria
BY SREEREMYA.S

2. Phenols are compounds with ArOH formula which
are
extremely toxic and found in different form or
together
with other elements (EPA, 2004). Simple phenol
is liquid
or solid with low melting point, but its boiling point
is high
because of hydrogen bonds. Phenol is slightly
solvable in
water due to its ability to make hydrogen bounds
with
water (9 gram in 100 ml water) (Morrison and

3. A large diversity of microorganisms is known to
be
competent of metabolizing many of the organic
pollutants
or chemicals generated and discharged
(Kobayashi and
Rittman, 1982). Metabolic processes are
governed by the
action of enzymes. Enzymes are precise for each
type of
reaction, thus microbial metabolism is a
procedure of
energy conversion continual by oxidation

4. The vapor of phenol can be easily absorbed
through
the skin. Phenol in solution form, easily passes
through
the skin, and its metabolism occurs in the liver,
although,
it could occur in the lung and kidney too. Phenol
is toxic
in environment and could decrease enzymatic
activity as
well. Also, it is toxic to fishes and is mortal
between 5 - 25
mg/l for them.

5. Moreover, direct effect of phenol is a
blocker for biologic reaction. Phenolic compounds
are
serious pollutant for rivers (EPA, 2004) and they
have
harmful effects such as growth inhibition,
decrease of
resistance against diseases, aquatic mortality and
increase in growth of weedy plants. If phenolic
pollution
goes to underground water, it causes serious
ecological
problems. Hence, allowable amount of phenol in
industrial outgoing must not be more than 0.5 mg

6. The nutritional requirements of microorganisms
normally
comprise nitrogen, phosphorus, potassium,
sodium,
calcium, magnesium, iron, trace elements and
carbon.
Dissolved oxygen is required for the respiration of
the
microbes under aerobic conditions.

7. Dissolved oxygen can
be considered as a nutrient related to other
dissolved
nutrients. Soil types affect the rate of mass
transport of
nutrients, pollutants of air, water and pH adjuster.
This
consequence on mass transportation in go back
affect the
degradation process