This document discusses a study on the antibacterial activity of green tea (Camellia sinensis). It provides background on the origin and composition of green tea. The study isolated several bacteria from the environment and tested green tea extracts against them. Methanolic extracts showed activity against Bacillus, streptococci, and staphylococcus but little activity against Proteus and Pseudomonas. The antimicrobial activity of green tea is attributed to polyphenols and catechins contained in the leaves. Daily green tea consumption can help eliminate harmful bacteria.

1. Running head: GREEN TEA (CAMELLIA
SINENSIS) 1
The Antibacterial Activity Exhibited By Green Tea (Camellia Sinensis).
Name
Institution

2. GREEN TEA (CAMELLIA SINENSIS) 2
Introduction
Tea is obtained from the foliage of less developed outgrowths of tree plant and has got
two botanical types; the green tea camellia sinensis (L) and the black tea camellia assamica (L).
Tea is produced in many parts of the world by both small-scale and large-scale producers. This is
because of the antibacterial activity that is associated with it, as a matter of fact, tea beverage is
the most consumed in the world. Tea has several secondary metabolites which include saponin,
catechin, caffeine, and theanine that serve human a great deal by acting as an antibacterial to
various micro-organisms like aureus, Pseudomonas, and staphylococcus that have negative effects
on humans (Kumar, et al., 2017). This term paper will talk about the origin of tea, its composition
and analyze how bacteria from secluded environment sources reacted on test with green tea
(Camellia sinensis) excerpts
According to Aneja (2003), Tea originated from China at around 2700 BC. It was mainly
added in boiled water to make it more palatable. Green tea comprises of several chemical
components with the abundant one being the polyphenols, in particular, the flavonoids which
include the catechins, catechin gallates and proanthocyanidins. Fresh green tea leaves contain
caffeine which has an approximate percentage of (3.50percent) of the entire weight when dry,
theobromine (0.15-0.20 percent), theophlloine (0.020-0.040 percent) inclusive of other
Methylxanthines, (6.50 percent), carbon-based acids (1.50 percent), chlorophyll (0.50percent) and
unrestricted amino acids of about (1-5.5percent) (Shihabudeen, Hans & Thirumurugan, 2010).
The study on how green tea excerpts depicted antibacterial activity against bacteria
secluded from the environment, revealed a vibrant function-ability of the extracts against the
identified and isolated bacteria as explained. The bacteria were first isolated from the air through
‘settle plate methodology' where selected bacteria were nurtured in plates at around 37.0 degrees

3. GREEN TEA (CAMELLIA SINENSIS) 3
Celsius and lasted up to 48 hours (Dubey, 2007). The bacteria were then identified through the use
of suitable macroscopic and microscopic method according to procedure designated by (Aneja,
2003). The biochemical characteristics and colony morphology of the bacteria were then studied
carefully. On identification of the bacteria, a thin homogeneous bacteria smudge was primed on a
beaker slide, from a bacteria culture grown on nutrient agar. It was then stained with crystal violet,
flooded with Gram's iodine solution and washed with distilled water. Absolute alcohol was used
to decolorize the slide till there was an absence of violet color. Finally, the slide was counterstained
using safranine and observed under a microscope.
Collection of green tea leaves was made from Himachal Pradesh, Palampur, from which
a number of extracts of the leaves were equipped in dissimilar diluents, after which antibacterial
activity was tested against the prepared bacteria samples secluded from the environment. Upon
bacteria isolation and preparation of slide and inoculums, keen tests were conducted using the
green tea extracts. several tests were then undertaken which were meant to reveal the antibacterial
activity of the green tea leaves, the tests included; the catalase test which was conducted by use of
hydrogen peroxide. A drop of typical saline was placed on a vibrant glass to test coagulase and
then adding a pure bacteria colony, an old bacteria culture was rubbed to an oxidase disc which
was water-logged with purified water positioned over a clean slide to test oxidase. Methyl red
experiment was done through inoculation of Mr-Vp fluid in replicas using 48h long-standing
cultures of bacteria established in an N.a, then nurtured for 24h at 37.0 degrees Celsius. Finally,
susceptibility test was done using the diffusion method (Taylor, Hamilton-Miller & Stapleton,
2017).
All bacteria which had been isolated were identified, the six bacteria included,
strephlococcus, Streptococcus, Proteus, Bacillus, E.coli, and Pseudomonas. The clean activities of

4. GREEN TEA (CAMELLIA SINENSIS) 4
the excerpts were tested by a method of disc diffusion. On testing and observation, the methanolic
excerpts were established to counter Bacillus, streptococci, and staphylococcus though all tests
carried out had little activity against Proteus and Pseudomonas. This was a clear indication that
green tea (Camellia sinensis) actively acted against most of the bacteria.
Conclusion
The antimicrobial activities of green tea are caused by the presence of polyphenols in the
tea leaves. Specific antioxidant polyphenols referred to as catechins, play a vital part in tea's ability
to inhibit the growth of bacteria. The most substantial catechins comprise, gallocatechin-3-gallete
(GCG).epicatechin-3-gallete (EcG), epicatechin (EC), epigallocatechin 3 gallate (ECG) and
epigallocatechin (EGc) (Carlson et al., 2007). Activity variation depends upon extract type and
concentration. Bacteria species may lead to differences on how the effects occur, for instance,
some bacteria species may portray stimulatory response and others inhibitory response. It is the
presence of catechins in the green tea leaves that results in the antimicrobial activity. Therefore,
consumption of tea daily principally the green tea (Camellia sinensis) can help eliminate dangerous
bacteria. Green tea (Camellia sinensis) also inhibits activities of several pathogenic bacteria which
cause skin contagions, cystitis, dental carries pyelonephritis and diarrhea including pneumonia.

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References
Kumar, A., Thakur, P., Patil, S., Payal, C. and Kumar, A. (2017). Cite a Website - Cite This For
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http://www.scienceflora.org/journals/index.php/rrst/article/viewFile/855/839 [Accessed 27 Nov.
2017].
Taylor, P., Hamilton-Miller, J. and Stapleton, P. (2017). [online] Available at:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2763290/ [Accessed 27 Nov. 2017].
Aneja K.R. Experiments in Microbiology, Biotechnology, and Plant pathology 4ed. 2003. NAI.
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