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SCREENING OF SOME EGYPTIAN PLANT EXTRACTS FOR BIOLOG-ICAL ACTIVITY AGAINST SOME PATHOGENIC BACTERIA [1]

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Plants and plant by-products are now gaining attractiveness in treatment of bacterial infections and food preservation. The objective of this study was to assess antibacterial activity of some Egyp-tian plant and plant by-products against the locally pathogenic isolates from patients having infectious diseases in our country. Screening of antibacterial activity of ethanol, methanol and hexane extracts of some plants: grape leaves (Vitis vinifera), mul-berry leaves (Morus alba), mallow leaves (Corcho-rus olitorius) and lemon leaves (Citrus limon) toward Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella sp., were investigated. Antibacterial activity was performed by the agar disc diffusion method. The eth-anol and methanol extract of tested plant leaves showed promising antibacterial activities against both Gram-positive and Gram-negative tested bacterial isolates due to its great ability to extract those polyphenolic and biological active compounds from natural sources which effectively act against broad spectrum bacteria. Ethanol followed by methanol were found to be the best solvents of choice to extract natural products to get maximum health and medicinal benefits. The results revealed that the extraction efficiency increase with polarity increasing of the solvents, hence the highest extraction done with ethanol and methanol and the lowest extraction with nonpolar solvent n-hexane did not exhibit any activity against all the tested bacteria. Irradiation at 5 and 10 kGy did not significantly affect the antibacterial activity of all tested plant leaves. Results indicate the potential of these plants for further work on isolation and characterization of the active compounds responsible for antibacterial activity and its exploitation as therapeutic agents
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1
Arab Univ.
J. Agric. Sci.,
Ain Shams Univ.,
Cairo, 25(2), 377-386,
2017
(Received 8 May, 2017)
(Revised 14 May, 2017)
(Accepted 16 May, 2017)
SCREENING OF SOME EGYPTIAN PLANT EXTRACTS FOR BIOLOG-
ICAL ACTIVITY AGAINST SOME PATHOGENIC BACTERIA [1]
Nermin, S. Abdel-Hamid2, Hanan H. Abdel-Khalek2, Z.A. Mattar2,
Khadiga A. Abou-Taleb1 and El.M. Ramadan1
1. Agric. Microbiology Depr., Faculty of Agriculture, Ain Shams University, Cairo, Egypt
2. Radiation Microbiology Department, National Center for Radiation Research and
Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Egypt.
Keywords: Irradiation, Antibacterial Plant extracts,
Pathogenic bacteria
ABSTRACT
Plants and plant by-products are now gaining
attractiveness in treatment of bacterial infections
and food preservation. The objective of this study
was to assess antibacterial activity of some Egyp-
tian plant and plant by-products against the locally
pathogenic isolates from patients having infectious
diseases in our country. Screening of antibacterial
activity of ethanol, methanol and hexane extracts
of some plants: grape leaves (Vitis vinifera), mul-
berry leaves (Morus alba), mallow leaves (Corcho-
rus olitorius) and lemon leaves (Citrus limon) to-
ward Staphylococcus aureus, Escherichia coli,
Pseudomonas aeruginosa and Salmonella sp.,
were investigated. Antibacterial activity was per-
formed by the agar disc diffusion method. The eth-
anol and methanol extract of tested plant leaves
showed promising antibacterial activities against
both Gram-positive and Gram-negative tested bac-
terial isolates due to its great ability to extract
those polyphenolic and biological active com-
pounds from natural sources which effectively act
against broad spectrum bacteria. Ethanol followed
by methanol were found to be the best solvents of
choice to extract natural products to get maximum
health and medicinal benefits. The results revealed
that the extraction efficiency increase with polarity
increasing of the solvents, hence the highest ex-
traction done with ethanol and methanol and the
lowest extraction with nonpolar solvent n-hexane
did not exhibit any activity against all the tested
bacteria. Irradiation at 5 and 10 kGy did not signifi-
cantly affect the antibacterial activity of all tested
plant leaves. Results indicate the potential of these
plants for further work on isolation and characteri-
zation of the active compounds responsible for
antibacterial activity and its exploitation as thera-
peutic agents
INTRODUCTION
Infectious diseases and microbial infections are
considered as the major killing factors in the third
world countries and the most important causes of
premature death. The difficulty of controlling the
sources of infection, the high cost of treat-
ment/prevention, poor compliance, low efficacy,
poor safety and drug resistance are the major fac-
tors that may retard the treatment of these diseas-
es. The drug resistance has further complicated
the treatment of infectious diseases in immune-
compromised AIDS and cancer patients (Singh et
al 2010 and Gawad et al 2015).
Plants are very good sources of medicinal
compounds that have continued to play a dominant
role in the maintenance of human health since
ancient times as reported by (Mariita et al 2011).
Medicinal plants represent a rich source of antimi-
crobial agents. These plants possess a potent me-
dicinal value that is due to the presence of a varie-
ty of phytochemical constituents in the plant tis-
sues which cast a definite physiological action on
the human body (Thalwal et al 2013).
Scientific investigations of medicinal plants
have been initiated in many countries because of
their contributions to health care. It was clear that
the primary benefits of using plant- derived medi-
cines are relatively safer than synthetic alterna-
tives, offering profound therapeutic benefits and
more affordable treatment. A lot of supplementary
2
Arab Univ. J. Agric. Sci., 25(2), 2017
Nermin, Abdel-Hamid, Hanan Abdel-Khalek, Mattar, Khadiga Abou-Taleb and Ramadan
treatment strategies were tried. Current social
trends in health care showed a definite movement
towards the use of natural remedies like medicinal
plants away from chemotherapeutic regimens
(Selvamohan et al 2012).
The use of crude extracts of plants parts and
phytochemicals, of known antimicrobial properties,
can be of great significance in the therapeutic
treatments. Also, use of plant essential oils in both
food and pharmaceutical industries has been de-
veloped interestingly; systematic examination of
plant extracts for these properties has become
increasingly important. The use of natural plant
antimicrobial compounds is important not only in
the preservation of food, but also in the control of
microbial growth in the disease condition (Rasool,
2013). Antimicrobial agents are effective in curing
diseases because of their selective toxicity against
pathogenic microbes without causing any harm to
the cells of the host (Thalwal et al 2013).
Plants contain innumerable constituents and
are valuable sources of new and biologically active
molecules possessing antimicrobial properties,
such as phenolic acids, flavonoids, tannins, lignin
and other small compounds. These compounds
possess numerous health-related effects such as
antibacterial, antimutagenic, anticarcinogenic, an-
tithrombotic, antioxidant, antibiofilm and vasodila-
tory activities (Osuagwu and Ihenwosu, 2014). In
particular, the antimicrobial activity of plant oils and
extracts has formed the basis of many applica-
tions, including raw and processed food preserva-
tion, pharmaceuticals, alternative medicine and
natural therapies (Thoppil et al 2014). It is also
important to mention that, plant by-products such
as leaves, bark and peels may be an abundant
source of polyphenols and tannins. Thus the use of
the waste as a source of the antibacterial com-
pound could provide health benefits to humans
and may be employed in food preservation pur-
pose (Balasundram et al 2006 and Wonghirun-
decha & Sumpavapol, 2012). Therefore, this
study was conducted to evaluate the antimicrobial
activities of four irradiated and nonirradiated plants
and plant by-products (grape, mulberry, mallow
and lemon) against local human pathogenic bacte-
rial isolates.
MATERIALS AND METHODS
Tested microorganisms
Nineteen bacterial isolates were collected from
Clinical Microbiology Laboratories, Ahmed Maher,
El Helal and Abbasiya Fever Hospital, Cairo, Egypt
and identified based on Bergey’s Manual of De-
terminative Bacteriology (Holt et al 1994).
Plant material
Four plants and plant by-products viz., (grape,
mulberry, mallow and lemon) were bought from a
commercial sources in Cairo, Egypt, and then di-
vided into three groups; the first was left without
irradiation and considered as control, while the
second and the third groups were exposed to
gamma irradiation at dose levels of 5 and 10 kGy.
Irradiation was performed in the National Center
for Radiation Research and Technology (NCRRT),
Nasr City, Cairo, Egypt, at dose rate 3.49269
kGy/h using the “Indian Gamma Chamber 4000 A”
with a 60Co source.
Preparation of soluble plant extracts
The dried leaves were ground into fine powder
with an electric blender and extracted by the cold-
maceration method as described by Anowi et al
(2012). Briefly, 50 g of each dried plant material
was soaked in 250 ml of the solvents ethanol,
methanol and hexane. The plant materials were
macerated at room temperature. After three days,
the supernatant was filtered through Whatman
No.1 filter paper and the filtrate was concentrated
by evaporating in a rotary evaporator (IKA, Ger-
many) at 40°C. The residue was weighed, dis-
solved in 2.5% dimethyl sulfoxide (DMSO) and
stored in the refrigerator at 4°C prior to use.
Antibacterial activity
The antibacterial activity of the tested plant ex-
tracts was determined according to (CLSI, 2012).
Briefly, Whatman filter paper no.1 discs were pre-
pared (diameter 6 mm). Discs were loaded with 40
μl of 50 mg/ml of each extract (dissolved in DMSO
2.5%) per disc and dried at room temperature. 100
μl bacterial suspensions (Five ml of a fresh growth
24h old culture with 106 CFU/ml) at wavelength
620 nm were spread on Muller-Hinton agar plate
(oxoid). The discs impregnated with plant extract
were placed on the agar surface. The plates were
incubated at 37°C for 24 h and the inhibition zone
was measured. Discs prepared with DMSO 2.5%
served as negative control. Ciprofloxacin (5 μg)
was used as a positive control. Three replicates
were carried out. The clearance zones (inhibition
zones mm) including the disc diameter were rec-
Screening of Some Egyptian Plant Extracts for Biological Activity Against Some Pathogenic Bacteria
Arab Univ. J. Agric. Sci., 25(2), 2017
3
orded, clearance zones having 6> mm were con-
sidered as positive results (Allam et al 2015).
Statistical Analysis
Standard deviation ± was applied using the Mi-
crosoft Excel program (2010)
RESULTS AND DISCUSSION
Antibacterial activity assay of plant extracts
In the present investigation, methanol, ethanol
and n-hexane extracts of the grape, mulberry, mal-
low and lemon leaves were evaluated for their an-
tibacterial activity against 19 bacterial isolates
which divided into; 5 isolates for each of Staphylo-
coccus aureus. (St), Escherichia coli (Ec), Pseu-
domonas aeruginosa. (Ps), and 4 isolates of Sal-
monella sp., as shown in Figs. )1-4). These results
indicated that both ethanol and methanol extracts
have antibacterial activity against all of the tested
pathogenic bacteria depending not only on the
tested bacteria, but also on the polarity of the sol-
vent (Padalia and Chanda, 2015). There are vari-
ous reports that antibacterial activity depends on
the solvent used, structure of the compound in the
extracts and the strain under investigation (Nair et
al 2006).
Data in Fig. (1) revealed that the antibacterial
activity of grape leaves ethanol extract showed
harbor antibacterial activity followed by methanol
extract against all tested pathogens, there was a
statistical difference in inhibition zones at the test-
ed concentration of both ethanol and methanol
extracts of grape for all tested bacterial isolates
and the largest diameter of inhibition zone was
obtained with Ec3 (29.7 and 24.2 mm), followed by
Ps1 (28.7 and 23.2 mm) and St1 (27.5 and 22.7
mm), respectively. These results indicated that, the
bacteria belonged genus Staphylococcus, Esche-
richia, and Pseudomonas were the most sensitivity
to tested plant leaves extract, it could be due to
these extracts contained high amount of Polyphe-
nolic derivatives such as: anthocyanins, leuco-
anthocyanins, Flavonoids (rutin, quercitrin,
isoquercitroside, luteolol), Gallic tannins and Cat-
echins which have remarkable antibacterial activity
have been suggested by (Alhamd et al 2015). On
the other hand, bacterial isolates of Sa2 and Sa4
(11.7 and 12.5mm), were considered as the least
sensitive against methanolic extract. Similar re-
sults have been found by Abed et al (2015) re-
ported that, grape leaves exhibited high antibacte-
rial activity against bacterial human pathogens,
such as Ps. aeruginosa and Staph. aureus. The
ethanol extracts of grape leaves showed broad
spectrum antimicrobial activity against Gram-
positive and Gram-negative bacteria (Oskay and
Sari, 2007). The antimicrobial activity of plant ex-
tracts depends on the type and amount of bioac-
tive compounds in the plant tissue and the
pathogen's inherent resistance (Martini et al
2004).
Fig. 1. Antibacterial activity of different grape leaf extracts (ethanol and methanol) against Staph. aureus,
E. coli, Ps. aeruginosa and Salmonella spp. for 24h at 37°C.
0
5
10
15
20
25
30
35
St1 St2 St3 St4 St5 Ps1 Ps2 Ps3 Ps4 Ps5 Ec1 Ec2 Ec3 Ec4 Ec5 Sa1 Sa2 Sa3 Sa4
Diameter of Inhibition zone (mm)
Bacterial strains
Grape Leaves ethanol
methanol
4
Arab Univ. J. Agric. Sci., 25(2), 2017
Nermin, Abdel-Hamid, Hanan Abdel-Khalek, Mattar, Khadiga Abou-Taleb and Ramadan
Results in Fig. (2) showed that, both ethanol
and methanol extract gave similar results in their
influence on antibacterial against tested bacteria,
and the mean of inhibition diameters of these ex-
tracts were between 12.2 to 24.5 mm & 11.0 to
23.2 mm respectively. The ethanolic extract of mal-
low leaves recorded the inhibition zone diameter
ranged from 16.2 to 24.5 mm, 12.2 to 23.0 mm,
13.2 to 21.5 mm and 14.2 to 16.7mm toward
Staph. aureus, Ps. aeruginosa, E. coli and Salmo-
nella spp, respectively. Whereas, the inhibition
zones were recorded in methanol extract against
Staph. aureus (ranged from 14.2 to 23.2mm), Ps.
aeruginosa (ranged from 11.0 to 23.2 mm), E. coli
(ranged from 12.7 to 20.7mm) and Salmonella spp
(ranged from 13.2 to 16.7mm). The obtained re-
sults are in the same line with Das et al (2010)
reported that, mallow leaves possess antimicrobial,
antitumor, and anti-inflammatory activities. Also,
Hayyawi (2012) and Mohammed (2016) reported
that, the ethanolic 96% and methanolic extracts of
mallow leaves exhibited significant antimicrobial
activity. They also found some active compounds
such as sterols, triterpenes, carotenoids, alkaloids,
tannins, saponins, coumarins, and carbohydrates
beside contains hydrocyanin and cardiac glyco-
sides in large quantity and, appreciable quantities
of flavonoids, and anthraquinones. The Phenolics
and Flavones compounds found in mallow extracts
inhibit the effect of the bacterial enzymes needed
for essential metabolic reactions by interfering with
the bacterial proteins.
Fig. 2. Antibacterial activity of different mallow leaf extracts (ethanol and methanol) against Staph. aureus,
E. coli, Ps. aeruginosa and Salmonella spp. for 24h at 37°C
With regard to mulberry leaves, a broad spec-
trum of antibacterial activity (ranged from 18.2 to
33.2 mm) against all tested pathogenic bacteria
have been illustrated by Fig. (3). These results
demonstrated that ethanolic extract harbor signifi-
cant antibacterial activity against all tested isolates
and the maximum growth inhibition was observed
against Ps. aeruginosa (ranged from 26.7 to
33.2mm) and Staph. aureus (ranged from 23.2 to
32.2mm), followed by E. coli (ranged from 24.2 to
31.2mm) and Salmonella spp (ranged from 17.7 to
29.2mm), respectively. Furthermore, antibacterial
potential was also noticed in methanol extracts
against Ps. aeruginosa (21.2 - 28.2mm) followed
by Staph. aureus (ranged from 18.2 to 27.2mm), E.
coli (ranged from 20.7 to 27.5mm) and Salmonella
spp. (ranged from 13.5 to 24.5mm). While hexane
extracts showed no activity against all tested iso-
lates. Different organic solvent extracts have dif-
ferent phytoconstituents in different amounts and
this explains why there is differential inhibition of
the bacteria (Padalia and Chanda, 2015). Several
investigators have been reported the antimicrobial
activity of mulberry leaves methanol extracts and
different species of mulberry leaves exhibited anti-
bacterial activity against Pseudomonas aerugino-
sa, Proteus vulgaris, Bacillus subtilis, Salmonella
typhi, Shigella flexneri and Candida albicans (Ad-
itya rao et al 2012 and Emniyet et al 2014). In
addition, Emniyet et al (2014) identified bioactive
0
5
10
15
20
25
30
St1 St2 St3 St4 St5 Ps1 Ps2 Ps3 Ps4 Ps5 Ec1 Ec2 Ec3 Ec4 Ec5 Sa1 Sa2 Sa3 Sa4
Diameter of inhibition zone (mm)
Bacterial strains
Mallow Leaves Ethanol
Methanol
Screening of Some Egyptian Plant Extracts for Biological Activity Against Some Pathogenic Bacteria
Arab Univ. J. Agric. Sci., 25(2), 2017
5
Fig. 3. Antibacterial activity of different mulberry leaf extracts (ethanol and methanol) against Staph. aure-
us, E. coli, Ps. aeruginosa and Salmonella spp. for 24h at 37°C
compounds which extracted from mulberry
leaves by ethanol. These compounds, namely,
giberellic acid and 9,12,15-octadecatrienoic . So,
antimicrobial activity can be related to these mole-
cules. The observed antimicrobial activities in mul-
berry leaves could possibly be due to the presence
of tannins, triterpenes, sterols, bioflavonoids, cou-
marins, volatile oil, alkaloids, organic acids and
amino acids, glycosides, and saponins (Emniyet
et al 2014 and Gunjal et al 2015).
The obtained results in Fig. (4) showed that,
among the three extracts of lemon leaves, the eth-
anol extract had the highest activity against Gram-
negative and Gram-positive bacteria but with vari-
able degrees of inhibition growth zones. All of the
bacterial isolates are sensitive to both ethanol and
methanol extracts as well, while hexane extract
had a weak or no antibacterial activity. The ethanol
extract of lemon leaves showed a better inhibition
zone than methanol extract. Maximum inhibition
was shown by ethanol extract against Ps. aeru-
ginosa (ranged from 17.2 to 28.0mm) and Staph.
aureus (ranged from 12.0 to 28.0mm) followed by
E. coli (ranged from 13.7 to 23.5 mm) and Salmo-
nella spp (ranged from 13.0 to18.0 mm), Also, the
inhibition zones were recorded in methanol ex-
tracts against Staph. aureus (ranged from 9.2 to
24.5mm) and Ps. aeruginosa (ranged from 13.2 to
23.7mm) followed by E. coli (ranged from 10.2 to
19.2mm) and Salmonella spp (ranged from 12.5 to
15.2mm). The present results are in agreement
with findings on antibacterial activities of lemon
leaves, Ewansiha et al (2016) reported that, etha-
nol is a good solvent for the extraction of citrus leaf
crude extract; ethanol gave the highest percentage
yield of 10.93%, followed by ethyl acetate with
9.42% while water extract gave the lowest yield of
3.67%. The antibacterial activity of lemon leaves
extracts exhibited by bioactive compounds such as
alkaloids, flavonoids, saponins, anthraquinones,
cardiac glycosides, tannins, steroids, terpenes,
resins, phenols and volatile oils
The present results (Figs. 1-4) are in agree-
ment with Motavalizadehkakhky et al (2013),
Moglad et al (2012) and Entezari et al (2009) with
varying degrees of potency. The difference in po-
tency may be due to the stage of collection of the
plant sample, soil nature, other environmental fac-
tors, storage conditions, the part of plant used,
method of extraction, method of screening, solvent
used, concentration of extract and different sensi-
tivity of the tested strains (EL-Zawahry et al 2013).
The mode of action of plant extracts and their natu-
ral components is related to: degradation of the
cell wall; damage to cytoplasmic membrane and
membrane proteins; leakage of intracellular con-
tents; coagulation of cytoplasm; interference with
active transport or metabolic enzymes; dissipate
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Arab Univ. J. Agric. Sci., 25(2), 2017
Nermin, Abdel-Hamid, Hanan Abdel-Khalek, Mattar, Khadiga Abou-Taleb and Ramadan
Fig. 4. Antibacterial activity of different lemon leaf extracts (ethanol and methanol) against Staph. aureus,
E. coli, Ps. aeruginosa and Salmonella spp. for 24h at 37°C
cellular energy in ATP form and depletion of proton
motive force (PMF) and electron flow, which can
cause cell death (Negi, 2012 and Allam et al
2015).
From previous results, it could be demonstrat-
ed that plants and plant by products play a vital
role in inhibited pathogenic bacteria when extract-
ed these plants by ethanol gave a higher antibac-
terial activity than methanol and n-hexane because
this solvent is able to dissolve both polar and non-
polar substances, including a variety of plant-
derived compounds, on the other side ethanol is a
low toxicity compared with methanol (Allam et al
2015). So, ethanol plant extracts were selected for
furthur studies.
Influence of gamma irradiation on antibacterial
activity of plant materials
Gamma-irradiation has been widely used as a
first choice sterilization method of raw medicinal
plants to be used in the phytotherapic industry
worldwide. In order to study the effect of gamma
irradiation on antibacterial activity of different
plants grape, mulberry, mallow and lemon leaves
were exposed to dose levels of 5 and 10 kGy then
the plants extracted with ethanol, and data were
recorded in Table (1). The results indicated that,
irradiation at dose levels of 5 and 10 kGy did not
affect the antibacterial activity of all tested plant
materials, it might be due to the content of phenolic
compounds which responsible for antibacterial
activity were stable and were not decomposed by
the irradiation (Ercisli et al 2008). The obtained
results were very close to other plants where Er-
cisli et al (2008) showed that no significant
changes in total phenolic contents of Glycyrrhiza
glabra roots were observed following gamma-
radiation treatment at dose levels of 5, 10 and 15
kGy, also Ibrahim et al (2016) reported that, irra-
diation at dose 10 and 30 kGy did not significantly
affect the antibacterial activity of aniseeds and star
anise waste residue extract. On the contrary, Zhu
et al (2010) reported that the doses of 2-10 kGy
significantly decreased three phenolic acids (p-
coumaric acid, Ferulic acid and sinapinic acid). The
difference in the effect of radiation on total phenolic
content may be due to plant type, geographical
and environmental condition, state of the sample
(solid or dry), phenolic content composition, extrac-
tion solvent, extraction procedures, temperature,
and dose of gamma irradiation, etc (Ibrahim et al.,
2016).
0
5
10
15
20
25
30
35
St1 St2 St3 St4 St5 Ps1 Ps2 Ps3 Ps4 Ps5 Ec1 Ec2 Ec3 Ec4 Ec5 Sa1 Sa2 Sa3 Sa4
Diameter of Inhibition zone (mm)
Bacterial strains
Lemon Leaves Ethanol
Methanol
Screening of Some Egyptian Plant Extracts for Biological Activity Against Some Pathogenic Bacteria
Arab Univ. J. Agric. Sci., 25(2), 2017
7
8
Arab Univ. J. Agric. Sci., 25(2), 2017
Nermin, Abdel-Hamid, Hanan Abdel-Khalek, Mattar, Khadiga Abou-Taleb and Ramadan
CONCLUSION
In the pursuit of searching for new antibiotics
and natural alternatives to chemical preservative
materials in food the role of grape, mulberry, mal-
low and lemon leave extracts cannot be negated
as that is evident with the present results. It can be
generally concluded that, the obtained results indi-
cated that, the ethanol and methanol extracts of
mulberry, mallow and lemon leaves possess signif-
icant antibacterial capacity and a good source of
various phytoconstituents which recommends fur-
ther research needed for isolation of bioactive
principles. The obtained results indicated that, the
tested plant and plant by- product extracts may be
a new source of alternatives to conventional anti-
biotics and as natural sources and their extracts
were recommended to be used as natural preserv-
atives in food against the screened bacterial spe-
cies which cause food-borne diseases and food
spoilage, also this study proved partly support and
justify the traditional use of these plant extracts for
treating infections in traditional medicine.
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... Black mulberry (Morus nigra L.), which originates from China, is cultivated for its fruits in Southern Europe and Southwest Asia (Mosayebi & Tabatabaei Yazdi, 2018). Mulberry fruits and leaf wastes have been widely studied (Abdel-Hamid et al., 2017;Huang et al., 2011;Koyuncu, 2004;Li et al., 2017;Mena et al., 2016;Natić et al., 2015;Okatan, 2018;Raman et al., 2016;Zhang et al., 2018); however, mulberry seeds have been underexploited, compared to grape pomace and seeds. A substantial amount of mulberry fruits is processed into juice and juice concentrates, indeed the mulberry production in Turkey exceeded 74 thousand tons (Tomas et al., 2015). ...
... In a recent study, Abdel-Hamid et al. (2017) revealed the antibacterial properties of grape and mulberry leaf extracts against Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhimurium. Additionally, Huang et al. (2011) suggested that anthocyanins from mulberry fruits might be used to prevent gastric carcinoma formation and Peixoto et al. (2018) described Vitis vinifera L. seed winery wastes as potential cytotoxic agents against MCF-7 breast adenocarcinoma and HeLa cervical carcinoma tumour cells. ...
... Several authors have deal separately with the chemical or the bioactive characterisation of grape or mulberry wastes (Abdel-Hamid et al., 2017;Aldubayan, 2018;Dopico-García et al., 2007;Poveda et al., 2018). However, few have addressed the individual characterization and the multiple bioactive properties of grape (Peixoto et al., 2018), and mulberry seeds (Kim et al., 2010). ...
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Grape (Vitis vinifera L. var. Albariño) and mulberry (Morus nigra L.) seeds pomace were characterized in terms of tocopherols, organic acids, phenolic compounds and bioactive properties. Higher contents of tocopherols (28 ± 1 mg/100 g fw) were obtained in mulberry, whilst grape seeds were richer in organic acids (79 ± 4 mg/100 g fw). The phenolic analysis of hydroethanolic extracts characterised grape seeds by catechin oligomers (36.0 ± 0.3 mg/g) and mulberry seeds by ellagic acid derivatives (3.14 ± 0.02 mg/g). Both exhibited high antimicrobial activity against multiresistant Staphylococcus aureus MIC = 5 mg/mL) and no cytotoxicity against carcinogenic and non-tumour primary liver (PLP) cells. Mulberry seeds revealed the strongest inhibition (p < 0.05) against thiobarbituric reactive substances (IC50 = 23 ± 2 µg/mL) and oxidative haemolysis (IC50 at 60 min = 46.0 ± 0.8 µg/mL). Both seed by-products could be exploited for the developing of antioxidant-rich ingredients with health benefits for industrial application.
... Beside the well-known pharmaceutical plants (e.g. guava, orange, garlic, onion, lemon, moringa, etc.), other plants such as grape, mulberry, mallow, purslane have been used as antimicrobial and/or antitumor agents (Penecilla and Magno, 2011;Lei et al., 2015;Abdel-Hamid et al., 2017). The extracts of both grape and mulberry were preferred as antibacterial agent than lemon and mallow extracts against S. aureus, Ps. aeruginosa, E. coli and Salmonella typhi (Abdel-Hamid et al., 2017). ...
... guava, orange, garlic, onion, lemon, moringa, etc.), other plants such as grape, mulberry, mallow, purslane have been used as antimicrobial and/or antitumor agents (Penecilla and Magno, 2011;Lei et al., 2015;Abdel-Hamid et al., 2017). The extracts of both grape and mulberry were preferred as antibacterial agent than lemon and mallow extracts against S. aureus, Ps. aeruginosa, E. coli and Salmonella typhi (Abdel-Hamid et al., 2017). ...
... Four pathogenic bacterial strains (S. aureus St3, Ps. aeruginosa Ps9, E. coli Ec3 and S. typhi Sa1) collected from clinical microbiology laboratories, and previously reported by Abdel-Hamid et al. (2017) were selected for this study. ...
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Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) analysis of the isolated essential oils obtained by steam distillation from the flowers, leaves, and stems of two plants, known to have medicinal activity, Achillea pachycephala Rech.f. and Achillea santolina L., collected from Khorasan, Northeast of Iran, as well as constituents obtained by solvent (hexane-ether and methanol) extractions of the aerial parts, resulted in the identification of 46 to 60 constituents (95.4 to 98.8% of the total oil and extracts) and 48 to 59 constituents (95.9 to 98.0% of the total oil and extracts), respectively. The hydrodistilled oil of three parts and the solvent extracts of A. pachycephala contain camphene, sabinene, 1, 8-cineole, camphor, borneol, terpinen-4-ol and β-caryophyllene as major constituents. In essential oils and extracts of A. santolina, 1, 8-cineole, camphor, terpinene-4-ol, fragranol, fragranyl acetate, α-terpinyl acetate, caryophyllene oxide, α-muurolol and some alkanes, alkanoic acids and esters were principle components. In vitro antimicrobial activity of essential oil of three parts and crude extracts (hexane-ether and methanol extract) of A. pachycephala Rech.f. and A. santolina L. were investigated by disc diffusion method and the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) determination. The studied samples were active against gram positive and gram negative bacteria. The maximum antimicrobial activities of both plants were shown by the essential oils and the hexane-ether extracts, as compared to methanolic extracts. Both oils and extracts exhibited higher activities against the gram negative tested bacterial strains. INTRODUCTION The genus Achillea L. (Asteraceae) is represented by about 115 species found in the Northern Hemisphere, mostly in Europe and Asia, and commonly known as yarrows (Radulovic et al., 2010; Benedek et al., 2008; Nemeth and Bernath, 2008). It has been represented in Iran by nineteen species including seven endemics (Mozaffarian, 2007). The Achillea L. species belong to the oldest medicinal plants that are used both for pharmaceutical purposes and in folk medicine . These plants contain a complex of different