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Evaluation of Antimicrobial Prospective of Parmotrema perlatum Hexane Extract



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Research Article ISSN 2277-3657
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Volume 4, Issue 2 (2015):47-53
International Journal of
Pharmaceutical Research &
Allied Sciences
Evaluation of Antimicrobial Prospective of Parmotrema perlatum
Hexane Extract
Shanu Hoda
, Pooja Vijayaraghavan
1, 2
Amity Institute of Biotechnology, Amity University, Sector 125, Noida, Uttar Pradesh 201303, India
Email address:
Subject: Pharmacognosy
The aim of the study was to test the antimicrobial potential of Parmotrema perlatum (P. perlatum) against
various bacterial and fungal pathogens. Hexane was used for the extraction of bioactive components from
P. perlatum. The efficacy of the bacterial and fungal pathogens against P. perlatum was tested by
measuring the zone of inhibition (ZOI) using disc diffusion method and by determining the minimum
inhibitory concentration (MIC) by micro-broth dilution method. Hexane extract of P. perlatum was found
as a potent inhibitor against the tested microorganisms. The extract showed significantly high antibacterial
property as compared to antifungal activity.The results of the present study indicated that P. perlatum has
potential antimicrobial compounds which can be further characterized for identifying new lead molecules
against various pathogenic microorganisms. Emergence of drug resistance and reduced efficiency of most
of the antibacterial and antifungal drugs necessitates identification of potential lead molecules with new
molecular targets and mechanism of action.
Key words:
Parmotrema perlatum, Antimicrobial, Zone of Inhibition, Minimum Inhibitory Conc.
Infectious diseases caused by pathogenic and
opportunistic microorganisms remain a major
threat to public health, in-spite of tremendous
progress in antimicrobial drug discovery.
Indiscriminate use of antibiotics, have lead to the
emergence of multidrug resistant pathogens that
are progressing towards final line of antibiotic
defence. This has lead to the search of new lead
molecules and targets. Plant derived antimicrobial
compounds and leads have been the source of
novel therapeutics since many years
. This may be
due to the fact that these compounds show
structural intricacy and chemical diversity required
to interact with antibacterial protein targets
provide vast opportunities for new drug
2, 3
Lichens and their products have been
traditionally used as medicine for centuries in
various parts of the world. They are dynamic
sources of natural antimicrobial drugs due to the
presence of various secondary metabolites as
phenolic compounds, dibenzofuranes, depsidones,
usnic acids, lactones, depsones, pulvunic acid
derivatives and quinines
. A lichen is a composite
organism that emerges from algae or cyanobacteria
(or both) living among filaments of fungus in a
mutually beneficial (symbiotic) relationship.
present study was done on the lichen Parmotrema
perlatum which belongs to the family Parmeliaceae
categorized under ascomycota
genus Parmotrema is usually characterized by
large foliose thalli with broad lobes, commonly
with a broad erhizinate marginal zone on the lower
surface, pored epicortex, thick-walled hyaline
ellipsoid ascospores, sublageniform or filiform
conidia and with or without marginal cilia
. Hale
and Ahti in 1986 gave earlier name Lichen
chinensis which was universally accepted. Later P.
perlatum was given a valid name by Hawksworth
in 2004. P. perlatum is distinguished by the
presence of stictic acid
The objective of the study was to
investigate the in-vitro antimicrobial property of P.
perlatum against common bacterial and fungal
pathogens. Three bacterial pathogens used in the
study were Escherichia coli, Pseudomonas sp. and
Bacillus subtilis. Among fungal pathogens
Cryptococcus neoformans, Candida albicans,
Aspergillus niger and Aspergillus fumigatus were
used. E. coli is a gram negative bacterium that can
be categorized as commensal, extra intestinal
pathogenic and intestinal pathogenic strain.
intestinal infections are common which include
urinary tract infection, abdominal infection,
meningitis and pneumonia. Intestinal pathogens are
obligate pathogens causing gasteoenteritis or
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. Pseudomonas is also a genus of gram
negative bacteria that commonly infects patients
with burn wounds, cystic fibrosis, acute leukemia,
organ transplants and intravenous-drug addiction.
Meningitis, septicemia, endocarditis, pneumonia,
malignant external otitis and endophthalmitis are
the most serious infections
. B. subtilis is a
ubiquitous gram positive bacterium that adapts to
various environmental changes by initiating
survival mechanism as biofilm formation and
It is not a potent pathogen but is
associated with outbreaks of food poisoning and
infection of the eye as reviewed by Frangois in
. C. neoformans is a pathogenic
encapsulated fungus that severely affects immuno-
compromised patients, especially those with AIDS.
The most serious clinical symptom of cryptococcal
infection is Meningoencephalitis
12, 13
. C. albicans
is a dimorphic yeast that causes mucocutaneous or
genitourinarty candidiasis
, superficial dermatitis
mostly in neonates
. A. niger is the 3
common disease causing Aspergillus that has been
associated with otomycosis
and cutaneous
. It is an unusual causative agent of
invasive pulmonary aspergillosis and pneumonia
A. fumigatus is an opportunistic pathogen which
majorly causes Invasive Aspergillosis (IA) in
immunocompromised patients
. The sensitivity of
pathogens against P. perlatum was examined by
calculating zone of inhibition (ZOI) by disc
diffusion method and by measuring minimum
inhibitory concentration (MIC) using micro-broth
dilution method.
Materials and methods
The bacteria used as the test organisms in the study
were Escherichia coli, Pseudomonas sp. and
Bacillus subtilis. The fungi used
were Cryptococcus neoformans (ATCC 66031),
Candida albicans (ATCC 10231), Aspergillus
niger (ATCC 16404) and Aspergillus fumigatus
(NAIMCC-F-02473). The bacterial cultures were
taken from Plant Secondary Metabolite
Laboratory, at Amity Institute of Biotechnology,
Amity University, Noida, India. A. fumigatus was
procured from NBAIM, Mau, India. C. albicans,
C. neoformans and A. niger were procured from
Himedia Laboratories, Mumbai, India. All
bacterial cultures were maintained on Nutrient
Agar/Broth (Himedia). C. albicans culture was
maintained on Yeast Peptone Dextrose media
(Himedia), C. neoformans and A. niger was
cultured on Potato Dextrose Agar/Broth (Himedia).
The culture of A. fumigatus was maintained on
Czapek Yeast Agar/Broth (Himedia).
Sample collection:
Lichen Parmotrma perlatum was collected from
local market, Noida, U.P., India. Sample was
cleaned under running tap water and dried at room
Preparation of P. perlatum extract:
100g of lichen was ground using mortar and pestle
to make fine powder and sieved. Powdered sample
was extracted in 400 ml hexane (Himedia) for 72
hours under constant shaking at 100 rpm. The
extract was filtered out using a three layered
muslin cloth followed by Whatmann no.1
(Himedia) and dried under vacuum in a rotary
evaporator. The dried extract was re-suspended in
5% Di-Methyl Sulfoxide (DMSO) (Himedia) at a
final concentration of 100µg/µl and stored at 4
Hexane extract was used to perform further
Sub-culturing the microorganisms in liquid
For bacterial culture 100 ml of Nutrient Broth
(NB) was prepared and autoclaved. 10 ml of NB
was transferred into 25 ml conical flasks. 50 µl of
each bacterial culture was inoculated in to the
media and sealed with a cotton plug. The flasks
were then placed in an incubator at 37°C for 24
hours. All procedures were carried out under
aseptic conditions.
For fungal cultures 100 ml of Yeast
Peptone Dextrose Broth (YPDB) was prepared and
sterilized. 20ml of YPDB was poured into 50 ml
conical flasks and 50 µl of each fungal culture was
inoculated. The conical flasks inoculated with A.
fumigatus and A. niger was kept at 28ºC for 7 days,
C. albicans and C. neoformans were kept at 30º C
for 48 hours.
Sub culturing the microorganisms in solid
100 ml of Nutrient Agar (NA), Yeast Peptone
Dextrose Agar (YPDA), Czapek Yeast Agar
(CzA), Potato Dextrose Agar (PDA) prepared for
bacterial and fungal culture respectively. Each
media was sterilized by autoclaving at 121ºC for
15 minutes. 20 ml media was poured into
autoclaved glass petri plates and cooled. Cultures
were then streaked using a nichrome wire loop
(Himedia) and then kept in incubator at respective
Screening the P. perlatum Extract for
Antimicrobial Assay:
The antimicrobial activity of the extract against the
microbial pathogens was determined by Kirby-
Bauer disc diffusion method
and PDA plates were spread with 100 µl of
bacterial and fungal suspension of 1*10
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respectively using sterile L-shaped spreader.
Sterile paper discs (Himedia) were placed on each
petri plates and 5 µl of extract was impregnated on
the discs. Penicillin, 1mg/ml (Himedia) was kept
as positive control for bacterial culture where as
fluconazole, 1mg/ml (Himedia) was used as
positive control for fungal strain. 5% DMSO was
kept as negative control. These plates were
incubated for respective time and temperatures in
the incubator. The antimicrobial activity was
evaluated by measuring the zone of inhibition
(ZOI) in mm around the discs formed at the end of
the incubation period.
Minimum Inhibitory Concentration (MIC):
The extract was tested for the lowest concentration
at which it is able to inhibit any visible microbial
growth. This was done using dose dependant
micro-broth dilution method in a 96 well plate
180µl of freshly prepared and autoclaved fresh
culture broth was added to 1
well of each row.
Further 20 µl of the extract was added making the
final volume 200 µl. The well contents were mixed
thoroughly. 100 µl of culture broth was added to
rest of the wells. Serial dilution was performed
along the row using 100 µl contents from the 1
well of each row. 100 µl of freshly prepared
microbial culture was then added to all wells. The
final concentration of the culture was kept at 10
cells / ml. In the 12
column, 100 µl of microbial
suspension and 100 µl culture broth was added,
which acted as (+) Control. The final concentration
of the extract was 1mg-1.8µg per well. The plate
was incubated at respective temperature. After
incubation period, the plate was observed visually.
The MIC was determined by measuring the optical
density at 530 nm using Bio-Rad micro plate
reader Model 680. The non inoculated broth was
kept as reference.
Antimicrobial assay:
The antimicrobial activity of hexane extract of the
lichen P. perlatum against the test microorganisms
was estimated on the basis of presence or absence
of inhibitory zones and their diameters.
Antibacterial activity of the extract is shown
in Table 1 and antifungal activity in Table 2. The
standards (Penicillin and Fluconazole) have shown
inhibition against all tested pathogens. The hexane
extract of P. perlatum proved to be most effective
against B. subtilis among bacteria. Among fungi
the extract showed most inhibition against A.
fumigatus and least against C. neoformans.
Table 1: Antibacterial activity of the hexane extract of P. perlatum against Bacterial Pathogens tested
using disc-diffusion assay. Results are shown in mm
Test Bacteria
Zone of Inhibition (mm)
Hexane extract
(100µg/µl) Standard(Penicillin,1 mg/ml)
E. coli 20 22.5
Pseudomonas sp. 18.4 19.6
B. subtilis 21.2 21
Table 2: Antifungal activity of the hexane extract of P. perlatum against the fungal pathogens tested
using disc-diffusion assay. Results are indicated in mm
Test Fungi Zone of Inhibition (mm)
Hexane extract
(100µg/µl) Standard (Fluconazole, 1
C. neoformans 9 21.6
C. albicans 10.4 22
A.niger 10.1 16.4
A. fumigatus 14 18.2
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Figure 1: Graph representing antibacterial activity of the hexane extract of P. perlatum against
Bacterial pathogens
Figure 2: Graph representing antifungal activity of the hexane extract of P. perlatum against fungal
pathogens tested in the present study
Minimum Inhibitory Concentration (MIC):
of the hexane extracts of P. perlatum was measured by visualizing the 96 well plates. Minimum
Inhibition is the minimum concentration of the compound or drug that can inhibit 100% microbial growth.
The results were calculated both visually and through ELISA reader.
Table 3: MIC calculated in (mg/ml) against all the bacterial Pathogens used in the present study.
Test Bacteria MIC (mg/ml)
E. coli 0.625
Pseudomonas sp. 1.25
B. subtilis 0. 312
Table 4: MIC calculated in (mg/ml) against all the fungal pathogens used in the study
Test Fungi MIC (mg/ml)
C. neoformans 2.5
C. albicans 2.5
A.niger 2.5
A. fumigatus 1.25
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Infectious diseases are the second leading cause of
death worldwide and are a major cause of concern
both in developing and developed countries. Since,
1940s antimicrobial drugs have been used to treat
various bacterial and fungal infections. However,
indiscriminate use of these life saving antibiotics
have led to emergence of Multi Drug Resistance
(MDR) in these microorganisms. In 2012, there
were about 4,50,000 new cases of MDR
tuberculosis. Resistance to earlier generation anti
malarial drug is reported in most malarial endemic
countries. MDR Klebsiella and E. coli have been
isolated in hospitals throughout United States.
Antibiotic resistance is also been reported among
some fungi that leads to Invasive fungal diseases in
immunocompromised patients
. Natural products
provide unlimited opportunities for new lead
molecules with vast chemical diversity. Most
clinically used antibiotics are either natural
products or semi synthetic derivatives of these
molecules. High through put technologies in the
area compound purification and structural
elucidation have led to considerable advancement
in the drug discovery process
Lichens have been reportedly used in dyes
in the earlier 17
and 18
century. The
antimicrobial property of lichen are well
documented in folklore, but till date none of the
lichen derived drugs are approved in the market
Various studies have confirmed that Lichens are
the store house of pharmacologically relevant
unique polyketide compounds
23, 24.
In this study in-
vitro antimicrobial potential of hexane extract from
the lichen P. perlatum has been examined against
Gram positive and Gram negative bacterial as well
as fungal pathogens. The extract revealed varying
degree of antimicrobial activity. The Hexane
extract of P. perlatum was tested against three
bacterial pathogens E. coli, Pseudomonas sps, B.
subtilis and four fungal pathogens C. neoformans,
C. albicans, A. niger and A. fumigatus. The
efficacy of the extract against these micro
organisms was tested by ZOI and MIC studies. The
results indicated high efficacy of the extract against
the bacterial pathogens. B. subtilis showed
maximum zone of inhibition 21.2 mm and
Pseudomonas sps gave the minimum zone of
18.4mm. The fungal pathogens were also tested for
ZOI using disc diffusion assay. A. fumigatus
showed high inhibition with 14mm Zone. The MIC
was calculated using micro broth dilution assay.
MIC of the extract was estimated at 0.312µg/ml for
B. subtilis and 0.625µg/ml for E.coli. The MIC for
fungal pathogens was high with A. fumigatus
showing minimum inhibitory concentration of 1.25
mg/ml and other fungal pathogens showing an
inhibition at 2.5 mg/ml. It has been reported in a
study that Parmotrema praesorediosum methanol,
acetone, hexane and dichloromethane extract
showed inhibitory activity against some bacteria
Crude extracts of P. praesorediosum tested using
disc diffusion technique showed antimicrobial
. Aqueous extracts of the lichen
Nephroma articum showed no antifungal
It has been concluded from our
experiments that the tested lichen extract has
significant antibacterial property in comparison to
antifungal activity. This result is in accordance
with other studies
27, 28
. Gulluce et al also found that
the methanol extract of the lichen Parmelia
saxatilis had stronger antibacterial than antifungal
. Similar finding was observed in a study
where extract of Parmelia perlata was prepared by
hot and cold extraction method using various
. Bacteria are more sensitive than fungi
because of the differences between the
composition and permeability of the cell wall.
Gram-positive bacteria have cell wall made of
peptidoglucanes and teichoic acids, where as that
of Gram-negative bacteria is made of
peptidoglucanes, lipopolysacharides and
. Fungal cell wall is poorly permeable
and consists of polysaccharides as chitin and
. The present study implies that the
bioactive compound can be obtained from hexane
extract of P. perlatum which can be used as natural
antimicrobial agents. These can be utilized for the
formulation of new drug to fight against pathogens.
The present work concludes that the hexane extract
of Parmotrema perlatum is more potent against the
bacterial cultures used in the study. The extract did
not show high efficacy against the fungal strains
used except Aspergillus fumigatus. Hence, it can be
summarised that the extract can be used as an
antibacterial agent. Further purification and
identification of the antimicrobial compound is
Corresponding Author would like to thank Amity
Institute of Biotechnology, Amity University,
Noida, India, for providing the necessary
infrastructure for carrying out this work.
“Cite this Article”
S. Hoda, P. Vijayaraghavan “Evaluation of
Antimicrobial Prospective of Parmotrema
perlatum Hexane Extract” Int. J. of Pharm. Res.
& All. Sci. 2015;4(2):47-53
Available online at
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Full-text available
Parmotrema is one of the larger genera segregated from Parmelia s. lat. Additional genera recently have been segregated from this large genus based mainly on morphological and chemical features. We have employed molecular data from three genes to continue a revision of the generic concept within the parmelioid lichens. A Bayesian analysis of nuclear ITS, LSU rDNA and mitochondrial SSU rDNA sequences was performed. The genera Canomaculina, Concamerella, Parmelaria and Rimelia appear nested within Parmotrema. Alternative hypotheses to maintain the independence of Canomaculina, Concamerella and Rimelia are shown to be highly unlikely and are rejected. As a consequence these three genera are reduced to synonymy with Parmotrema. An alternative topology segregating Parmelaria from Parmotrema s. lat. cannot be rejected with the dataset at hand. However we have established that this genus is closely related to Parmotrema rather than to cetrarioid species as was considered previously. The revised genus Parmotrema includes species that have an upper cortex consisting of a palisade plectenchyma or rarely paraplectenchyma with vaults, have a pored or fenestrated epicortex, lack pseudocyphellae, have or lack cilia, have laminal, perforate or eperforate apothecia, usually have simple rhizines and filiform, cylindrical, bacilliform or sublageniform conidia. It is closely related to Flavoparmelia but the status of these genera requires further investigation. Nineteen new combinations are made.
Full-text available
Although prokaryotes ordinarily undergo binary fission to produce two identical daughter cells, some are able to undergo alternative developmental pathways that produce daughter cells of distinct cell morphology and fate. One such example is a developmental programme called sporulation in the bacterium Bacillus subtilis, which occurs under conditions of environmental stress. Sporulation has long been used as a model system to help elucidate basic processes of developmental biology including transcription regulation, intercellular signalling, membrane remodelling, protein localization and cell fate determination. This review highlights some of the recent work that has been done to further understand prokaryotic cell differentiation during sporulation and its potential applications.
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The present study was carried to determine the antibacterial, anthelmintic and antioxidant activity of a macrolichen Parmotrema pseudotinctorum (des. Abb.) Hale (Parmeliaceae) collected from forest area of Bhadra wildlife sanctuary. The extract exhibited marked antibacterial activity. The minimum inhibitory concentration of the extract was found to be lesser in case of Gram negative bacteria than Gram positive bacteria. The lichen extract exhibited a dosedependent inhibition of spontaneous motility. At doses of 15 and 20mg/ml, the effects were comparable with that of standard anthelmintic. The lichen extract exhibited marked antioxidant activity in a dose dependent manner in DPPH free radical scavenging assay and Fe+3 reducing assay. The methanol extract exhibited marked antioxidant activity by scavenging DPPH* (free radical) and converting into DPPHH. The absorbance was found to increase with the dose of methanolic extract and standard which is suggestive of reducing power. Preliminary phytochemical analysis showed the presence of secondary metabolites namely tannins and steroids in the extract. Thin layer chromatography revealed the presence of Atranorin and Lecanoric acid in the lichen material. The efficacy of the solvent extract may be due to the presence of various constituents. Further studies on isolation of secondary metabolites and their biological activities in vitro and in vivo are to be carried out.
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Objective(s): The ongoing increasing antibiotic resistance is one of the biggest challenges faced by global public health. The perennial need for new antimicrobials against a background of increasing antibiotic resistance in pathogenic and opportunistic microorganisms obliges the scientific community to constantly develop new drugs and antimicrobial agents. Lichens are known prolific sources of natural antimicrobial drugs and biologically active natural products. This study was aimed to explore in vitro antimicrobial activity of lichen Parmotrema sp. Material and Methods: The methanol and aqueous extracts of lichen Parmotrema sp. was extracted using Soxhlet extractor. Antibiotic assessment of methanol and aqueous extracts was done against eight bacterial (Escherichia coli, Staphylococcus aureus, Proteus mirabilis, Salmonella sp., Shigella sp., Enterococci faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae,) clinical pathogens and five plant pathogenic fungal strains (Aspergillus terreus strain JAS1, Scedosporium sp. JAS1, Ganoderma sp. JAS4, Candida tropicalis and Fusarium sp.) by Kirby-Bauer method. Results: The methanol lichen Parmotrema sp. extract inhibited all the test organisms. The highest antibacterial activity was found against Pseudomonas aeruginosa and Staphylococcus aureus. The weakest activity was manifested in Salmonella sp. and Scedosporium sp. JAS1. Strong antifungal effect was found against Ganoderma sp. JAS4 and Fusarium sp. The aqueous lichen Parmotrema sp. extract revealed neither antibacterial nor antifungal activity. Conclusion: The present study shows that tested lichen Parmotrema sp. extracts demonstrated a strong antimicrobial effect. That suggests the active components from methanol extracts of the investigated lichen Parmotrema sp. can be used as natural antimicrobial agent against pathogens.
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Parmotrema A. Massal. is a common lichen genus scattered throughout the Korean Peninsula; however, no detailed taxonomic or revisionary study of this genus has been conducted for nearly two decades. Therefore, this study revised the taxonomy of this genus based on specimens deposited in the lichen herbarium at the Korean Lichen Research Institute and samples wereidentified using recent literature. In this revisionary study, a total of eighteen species of Parmotrema including eight new records [Parmotrema cetratum (Ach.) Hale, Parmotrema cristiferum (Taylor) Hale, Parmotrema grayanum (Hue) Hale, Parmotrema defectum (Hale) Hale, Parmotrema dilatatum (Vain.) Hale, Parmotrema margaritatum (Hue) Hale, Parmotrema pseudocrinitum (Abbayes) Hale, and Parmotrema subsumptum (Nyl.) Hale] are documented. Detailed descriptions of each species with their morphological, anatomical and chemical characteristics are also given and a key to the known Parmotrema species of the Korean Peninsula is presented.
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A survey of the parmotremoid lichens occurring in the central area of Rio Grande do Sul State (Brazil) revealed 31 species of Parmotrema A. Massal., distributed in three groups corresponding to the former genera Canomaculina Elix & Hale, Parmotrema s. str. and Rimelia Hale & Fletcher. All species are described, illustrated, commented and special notes compare similar species as an aid to identification.
Lichen metabolites exert a wide variety of biological actions including antibiotic, antimycobacterial, antiviral, and inflammatory, analgesic, antipyretic, antiproliferative and cytotoxic effects. Even though these manifold activities of lichen metabolites have now been recognized, their therapeutic potential has not yet been fully explored and thus remains pharmaceutically unexploited. In this mini-review, particular attention is paid to the most common classes of small-molecule constituents of lichens, from both the chemical viewpoint and with regard to possible therapeutic implications. In particular, aliphatic acids, pulvinic acid derivatives, depsides and depsidones, dibenzofuans, anthraquinones, naphthoquinones as well as epidithiopiperazinediones are described. An improved access to these lichen substances in drug discovery high-throughput screening programs will provide impetus for identifying novel lead-compounds with therapeutic potential and poses new challenges for medicinal chemistry.
The species of Parmelia mentioned in India Materia Medica are useful in treating a number of ailments and they are used in large quantities as food supplement in India. In this study, the crude extracts obtained from the Parmelia perlata by cold and hot extraction method using different solvents were tested for their antimicrobial activity. Results indicated that the antibacterial activity of P. perlata crude extracts was more on Clavibacter michiganensis, moderate on Pseudomonas solanacearum and it was less on Escherichia coli than streptomycin. The Fusarium oxysporum and Rhizopus nigricans were more susceptible, and Aspergillus niger was less susceptible to all crude extracts than bavistin. The antibacterial activity was also high in compound-I and compound-II and it was least in compound-III, than streptomycin. The antibacterial activity of compound-II acted highly against C. michiganensis and P. solanacearum; it was less against to E. coli. The compound-I and compound-III were more active against C. michiganensis, moderately active against P. solanacearum and less active against to E. coli when compared to streptomycin. The antifungal activity was more in compound-II and moderate in compound-I and it was less in compound-III .The compound-II was more active against F. oxysporum and R. nigricans than compound-I and compound-III, and less active against A. niger than bavistin. The compound-I and compound-III did not show any activity against A. niger. The overall data presented indicates that the crude and isolated compounds of P. perlata extracts have antimicrobial property, in that antibacterial activity was found in all extracts than antifungal activity.
Objective To test efficacy of Parmelia perlata (P. perlata), which is used in traditional medicine for rapid wound healing against test bacteria that cause wound infections.Methods Different solvents such as methanol, ethyl acetate and acetone were used for extraction of P. perlata. The sensitivity of the test bacteria to solvent extracts of P. perlata was tested by measuring the zone of inhibition on growth media and by determining the minimal inhibitory concentration and minimal bactericidal concentration.ResultsMethanol, ethyl acetate and acetone extracts of P. perlata have shown inhibitory activity against Staphylococcus aureus (S. aureus).Conclusions The results of the present study indicate that P. perlata has potential antibacterial compounds against S. aureus that causes multitude of skin infections among human beings. Development of drugs from natural compounds can help us to combat antibiotic–resistant bacteria.