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Review Article: Development of Probiotic Candidate in Combination with Essential Oils from Medicinal Plant and Their Effect on Enteric Pathogens: A Review



Medicinal plants and probiotics both have very high potential in terms of their antimicrobial activity against antibiotic-resistant enteric pathogens. The probiotics being enteric microorganism do not have any parasitic effect on human beings. They have been an integral part of daily food for centuries. They have been shown to have health beneficiary properties. The probiotics retard the growth of the microorganisms, while essential oil kills them. Combining the effect of medicinal plant extract and probiotics may be a new approach due to their complementary antimicrobial effects and practically no side effects. The synergistic effect of the essential oil and probiotics will be necessarily higher than using them alone as health product.
Hindawi Publishing Corporation
Gastroenterology Research and Practice
Volume 2012, Article ID 457150, 6pages
Review Article
Development of Probiotic Candidate in Combination with
Essential Oils from Medicinal Plant and Their Effect on Enteric
Pathogens: A Review
Shipradeep,1Sourish Karmakar,1Rashmi Sahay Khare,2Sumedha Ojha,1
Kanika Kundu,2and Subir Kundu1
1School of Biochemical Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi 221005, India
2Chemistry Section, MMV, Banaras Hindu University, Varanasi 221005, India
Correspondence should be addressed to Subir Kundu,
Received 17 March 2012; Revised 4 May 2012; Accepted 12 May 2012
Academic Editor: Antonio Gasbarrini
Copyright © 2012 Shipradeep et al. This is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Medicinal plants and probiotics both have very high potential in terms of their antimicrobial activity against antibiotic-resistant
enteric pathogens. The probiotics being enteric microorganism do not have any parasitic eect on human beings. They have been
an integral part of daily food for centuries. They have been shown to have health beneficiary properties. The probiotics retard the
growth of the microorganisms, while essential oil kills them. Combining the eect of medicinal plant extract and probiotics may
be a new approach due to their complementary antimicrobial eects and practically no side eects. The synergistic eect of the
essential oil and probiotics will be necessarily higher than using them alone as health product.
1. Introduction
The plants have been used in Ayurvedic medicines from
ancient times. The extracts from these plants have shown
potent antimicrobial eect. Recently, much work has been
done on extraction of chemicals responsible for the antimi-
crobial eect from these plant species. It has been reported
that the essential oils extracted from these plants have potent
activity against microorganisms [1]. However, the studies
have shown that these essential oils have very high MIC
(minimal inhibitory concentration) against beneficial enteric
bacteria known as probiotics [2,3].
Probiotic is the term as per WHO definition denotes
“live microbial feed supplement which beneficially aects the
host animal by improving its intestinal microbial balance.
As the definition clearly indicates, most of the intestinal
bacteria have an important role to play in the digestive
system. Earlier, probiotics were given to animals to improve
their health, but later much research has been put in
the development of the probiotics for human health. The
major probiotics that are taken in the diets belongs to the
genera of Lactobacilli and Bifidobacteria [4]. Apart from
that, the gut flora predominately has obligate anaerobes that
include Bifidobacteria, Clostridia, Eubacteria, Fusobacteria,
Peptococci, Peptostreptococci,andBacteroides.Onlyabout1%
of these bacteria are facultative anaerobes belonging to the
genera of Lactobacilli, Escherichia coli, Klebsiella, Streptococ-
cus, Staphylococcus,andBacilli. In the case of newborns,
food habits play a major role in the development of enteric
flora. The breastfed babies normally have abundance of
Bifidobacteria, while the others have complex microflora
in their enteric system. Bifidobacterium sp. can be isolated
mostly from the feces of infant milk feed baby. However,
in the case of infants fed on normal formula based food
products the gut flora is found to be rich in Enterobacteria,
Lactobacilli, Bacteroides, Clostridia,andStreptococci. These
gut flora help to digest the milk-based food and oer the
primary line of defense against the pathogenic bacteria.
The infants have weak but developing immune system [5].
These enteric bacteria help the infantile immune system to
fight against pathogenic enteric bacteria by lowering the pH
of the gut, rendering it unsuitable for pathogenic bacteria
to survive [6]. Even the medical practitioners recommend
probiotics-based supplement to both patients suering from
2Gastroenterology Research and Practice
enteric diseases. The most popular probiotics supplements
belong to the genera of Lactobacilli and Bifidobacteria. The
recommended dosage of 109–1010 CFU is considered a
minimum for healthy enteric system [7].
Present review emphasizes on the synergistic antimicro-
bial eect of essential oil of the Lamiaceae family and probi-
otics administered together as flavored fermented milk prod-
ucts. The advantage of using such a combination is its benefi-
cial eect with its antimicrobial property. The probiotics can
help in improving the gut epithelial conditions while essen-
tial oil acts on killing the pathogens present in the human
2. Health Benefits of Probiotics
Probiotics, though recently popular, have been an integral
part of the human diet for centuries. All the civilizations from
ancient times have documented the benefits of curd in the
human diet. The lactose-tolerant people are always advised
to take curd with their diet. The curd is rich in Lactobacillus
sp. and Streptococcus sp. These microorganisms utilize the
lactose present in milk-based food and convert it to lactic
acid [8].Theoccurrenceofflatulenceincarbohydrate-
intolerant individuals is also observed with fatty acid. The
carbohydrates that are not fully digested due to lack of
certain enzymes in human being can also be digested with
probiotics. These carbohydrates are fermented into short-
chain acids such as butyric acid, lactic acid, or acetic acid
[9]. These acids are readily utilized in by human cells for
ATP metabolism providing energy to the individuals. The
lactic acid also helps in protein metabolism by coagulating
the protein chunks from meat inside the intestine [10].
Formation of hydrogen peroxide is also prevented by cata-
lases produced from probiotics preventing protein-caused
rancidity [1113]. Hydrolysis of sarcoplasmic protein was
also observed with many species of Lactobacillus genus [14
16]. Coprecipitation of cholesterol with bile salts at lactic
acid-induced lower pH is also observed in in vitro conditions
Probiotic microorganisms are also found to be involved
in synthesis of vitamins. The probiotics microorganisms are
known to synthesize biotin and vitamin K [18]. Apart from
that, they are also involved in the ions absorption such as
The probiotic microorganisms are also involved in the
enhancement of expression of certain pattern recognition
receptors. Pattern recognition receptors such as TLRs have
active role in wound healing process. The intestinal cells have
high need for these receptors for supporting their process of
proliferation and dierentiation, healing the wounds made
due to irregular bowel movement [19]. The short-chain
fatty acid produced from carbohydrate metabolism also
enhances the process of proliferation and dierentiation of
gut epithelial cells.
The probiotics have also a major role to play in preven-
tion of allergies in children [5]. However, the connection
of probiotics and immune system regulation is still under
investigation. It has been observed that with allergy-prone
adults and children, the count of Lactobacilli and Bifidobac-
teria is lower. It has been also observed that administration
of probiotic strains during prenatal stage can decrease the
chance of atopic eczema. In addition, the production of pat-
tern recognition receptors, interleukin, and growth factors
from the probiotic microorganisms in gut epithelia also play
an important role in prevention of allergies. Therefore, it
can be inferred that these microorganisms have direct role
in immune system regulation [5]. Apart from that, these
microorganisms also play a role in immune response mod-
ulation. The probiotic microorganisms interact with the gut-
associated lymphoid tissue (GALT) [20]. The probiotics are
involved in cytokine synthesis, that plays an important role in
immune system regulation. However, due to insucient clin-
ical trial, administration of probiotics in immunosuppressed
individuals is still prohibited.
It has been also observed from both in vitro and in vivo
studies that probiotics may prevent cancer [21]. It has
been found that daily intake of fermented milk products
substantially decrease the concentration of nitroreductases,
azoreductases, and β-glucuronidase in the gut. These micro-
bial enzymes are associated with carcinogen production
in the gut [22]. Lactobacillus casei have also shown an
antigenotoxic eect. It prevents inducible DNA damage in
the tumor target tissues of gastrointestinal tract of rats.
3. Antimicrobial Effect and
Mechanism of Action
Probiotics have a known antimicrobial eect. They are
very potent against pathogens. There are several proposed
mechanisms for the antimicrobial action of the probiotics.
Bacteriocins, organic acids, hydrogen peroxide, diacetyl, and
other inhibitory chemicals are released by the probiotics [23].
All of these chemicals are known for their potent antimi-
crobial eects. Bacteriocins are toxic chemicals released by
the probiotics, that are highly potent against most of the
bacteria. However, the most feasible mode of action seems
to be lowering of pH with release of organic acids such as
lactic acid [24,25]. In the limiting condition of available
substrates inside the intestine, lowering the pH ensures the
survival of acidophilic micro-organisms only. The growth
of the pathogens gets inhibited at acidic conditions, slowing
the metabolic process in them. Lactobacillus strain GG has
been reported to produce inhibitory chemicals, possibly a
microcin, that have high activity against pathogenic microor-
ganisms. It has been found eective against Clostridium spp.,
Bacteriodes spp., Enterobacteriaceae spp., Staphylococcus spp.,
and Pseudomonas spp. in microbiological assays. Lactocidin
released by strains of lactobacillus acidophilus is found active
against Staphylococcus aureus and Pseudomonas aeruginosa
[26]. There has been a study that Lactobacillus acidophilus
LB release chemicals that are eective against both gram
positive and gram negative microorganisms. These chemicals
released in the broth were eective against Staphylococ-
cus aureus,Listeria spp.,Salmonella typhimurium,Shigella
flexneri,E. coli,Klebsiella pneumoniae,Bacillus cereus,Pseu-
domonas aeruginosa,andEnterobacter spp. [27]. However,
Gastroenterology Research and Practice 3
Tab l e 1: MICs of essential oil against known pathogenic microorganisms.
Bacterial strains Coleus aromaticus Shyama tulasi Rama tulasi
Providencia rettgeri 4μl/mL 3μl/mL 2μl/mL
Shigella flexneri 1μl/mL 5μl/mL 5μl/mL
Shigella dysentery 3μl/mL 5μl/mL
Vibrio parahaemolyticus 2μl/mL 5μl/mL 5μl/mL
Salmonella enteritis 4μl/mL 2μl/mL 3μl/mL
Salmonella typhi 0.5 μl/mL 2μl/mL 2μl/mL
Vibrio cholerae 2μl/mL 2μl/mL 1μl/mL
the chemical did not have any inhibitory eect on probiotics
strains such as Lactobacillus and Bifidobacterium spp. This
can be explained by the similarity of survival conditions
of both these microorganisms. Some of the strains of
Bifidobacterium spp. have potent activity against Salmonella
typhimurium. However, not all the strains of Bifidobacterium
spp. have the activity against S. typhimurium. All of the pro-
biotics have higher survivability in low pH conditions. These
microorganisms produce acids by breaking the carbohydrate
present in the diet. The properties of acid production and
acid survivability increase their survivability in the toughest
of conditions [28,29]. The adherence property of the
probiotic microorganisms also ensures their longevity in the
human guts [30]. However, the probiotic strains have shown
an eective potential in inhibiting the adhesion of pathogen
such as E. coli and Salmonella enterica in in vitro conditions
[31]. The potential of adhesion inhibition by the probiotics
is credited to the mucin production and competitive binding
to gut epithelial receptor sites. Lactobacillus acidophilus
LA1 has high calcium independent adhesive property that
inhibits the invasion of enteropathogenic bacteria. Mucins
are complex glycoprotein that inhibits the enterobacterial
adhesion by protection of intestinal epithelial cell receptors.
Both MUC2 and MUC3 produced by Lactobacillus spp. are
potent examples of Mucins that have adhesion inhibitory
activity against enteropathogens.
4. Antimicrobial Effects of Essential Oils from
Medicinal Plants
There has been lot of studies in recent year that have
established the antimicrobial eect of essential oils of
medicinal plants such as plants of the Lamiaceae family
[2,3]. The essential oils predominately present in the
leaves of the plant species have a pleasant aroma. They are
commonly used in flavor enhancement in food industries,
as they are safe for human consumption. These essential
oils have been shown to have a bactericidal eect. The
plant species of Lamiaceae family have been proven eective
against Uropathogen [32]. Tab l e 1 shows the MICs of Coleus
aromaticus and Ocimum sanctum (Rama Tulasi and Shayama
Tul a s i) against few known enteric pathogens [32]. The
essential oil from the plants of Carum carvi, Coleus aro-
maticus, Rama Tulasi, Shyama Tulasi, Citrus aurantium var.
amara,foeniculumvulgare dulce, Illicium verum, Lavandula
angustifolia, Mentha arvensis, Mentha x piperita,andTra-
chyspermum copticum have been shown to be eective against
variety of microorganisms. These plants extracts have been
found eective against Bacteroides fragilis, Candida albicans,
Clostridium dicile, Clostridium perfringens, Enterococcus
faecalis, Escherichia coli, Eubacterium limos, Staphylococ-
cus aureus, Klebsiella oxytoca, Proteus vulgaris, Escherichia
coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus
mirabilis,andPeptostreptococcus anaerobius [2]. The MICs
against these microorganisms varies from 0.1 to 3%v/v.
The MICs of the same plant extracts against probiotic
microorganisms such as Bifidobacterium bifidum, Bifidobac-
terium longum, Lactobacillus acidophilus,andLactobacillus
plantarum are much higher in magnitude than the pathogens
[2]. Therefore, if the dosage of essential oil is low, then
it eectively wipes out the pathogens without harming the
beneficial probiotics.
5. Proposal on Synergistic Effect of Probiotics
and Essential Oil from Plants
The essential oils have high MIC values for probiotics,
while it is eective in much lesser concentration against
the pathogens. The above phenomenon makes it possible
that both probiotics and essential oil can be administered
together to cure pathogenic infection in human gut. They
both can be combined to form essential oil-flavored fer-
mented milk products such as flavored curd beverages or
flavored yogurt. Antibiotics coupled with probiotics are
already present in the market, but these medicines mostly
face stichallenge from antibiotic-resistant bacteria. Further
frequent use of the antibiotics may lead to the development
of antibiotic resistance in the pathogenic microorganisms
too. Hence, the strategic use of probiotics may be beneficial
to curb the growing phenomenon of antibiotic resistance.
Probiotics have antimicrobial properties associated with the
production of bacteriocin-like chemicals. However, it mostly
arrests the proliferation of the pathogens by lowering the pH
in the gut environment. The pathogens do not normally have
any mechanism against the action of essential oils. Essential
oils are resistant against enzymatic activity of β-lactamase
produced as a countermeasure against β-lactam antibiotics.
The use of probiotics lowers the survivability chances of
pathogen, while the essential oil in lower dosage ensures
their complete killing inside the human digestive tract. The
probiotics may also impart its good benefits discussed earlier.
4Gastroenterology Research and Practice
Tab l e 2: Test of the beverages made with mixing dierent concentration of essential oil of Coleus aromaticus, Rama tulasi, and Shyama tulasi against common pathogens for 24hrs at 37C
(sign denotes no pathogen; + sign denotes the presence of pathogen).
S. Bacteria Gram Beverage Beverage Beverage Beverage Beverage Beverage Beverage Beverage Beverage
number +ve/ve123456789
(1) Citrobacter freundii ve −−−−−−−−−
(2) Proteus mirabilis ve + + + −−−+−−
(3) Klebsiellal pneumoniae ve++++++++
(4) E. coli ATCC 25922 ve + −−++++−−
(5) Entero. faecalis ATCC 29912 +ve −−−−−−−−−
(6) Salmo. typhi MTCC 3216 ve −−−−−−++
(7) Staph. aureus ATCC 25923 +ve + + +++−−
(8) Salmonella typhimurium ve + −−−−−−−−
(9) Salmonella paratyphi ve + + +−−++
(10) Vibrio cholerae ve −−−−−−−−−
(11) Pseudo. aeru. ATCC 27853 ve −−−−−−−−−
(12) Proteus vulgaris ve + + −−−−+−−
(13) Listeria monocytogenes +ve + + +++−−
(14) Shigella flexneri ve −−−+−− ++
(15) Helicobacter pylori ve −−−−−−−−−
(16) Strptococcus heamophila +ve + −−−−−−−−
Gastroenterology Research and Practice 5
Apart from that, the fermented milk product will surely
impart benefits in terms of supplying nutrients such as
sugar, water, salt, and acid to the human body. Adding
essential oil will not only give an aromatic flavor to these
fermented milk beverages or products, but also increase their
shelf like considerably by preventing the microbial spoilage.
The product will act as both probiotic health product and
preventive antimicrobial product against enteric pathogens.
In an independent study, beverages A, B, and C were
prepared with probiotic curd (109CFU/ml) [33]withvary-
ing concentration of essential oil of Coleus aromaticus, Rama
Tul a s i and Shyama Tulasi,respectively[1]. The beverages
A1, A2, and A3 were prepared with essential oil of Coleus
aromaticus; beverage B1, B2, and B3 with essential oil of
Shyama Tulasi and beverages C1, C2, and C3 with essential
of Rama Tulasi in varying concentrations of 1, 2, and 3 μl/ml
respectively. These beverages were then grown with common
enteric pathogens in equal concentration, measured by count
of CFU, in nutrient broth for 24 hours in airtight culture
vials at 37C to simulate the anaerobic condition prevailing
in the intestine [34]. The individual vial was tested for the
traces of pathogen as seen in Tab l e 2 with sign indicating
the cidal eect of the beverage against the pathogen (no
growth of the pathogens), while + sign indicated the growth
of the pathogen. The sample beverages were found to be
highly eective in inhibiting the growth of the pathogen. The
shelf life of the beverages was also found to be significantly
higher than normal probiotics [34]. The test results can be
interpreted as the beverage’s capacity for prevention against
enteric pathogens. The use of beverage does not need the
stringent FDA regulations, yet it will impart the benefit of
preventive diseases.
6. Conclusion
Probiotics and essential oils both have a great potential
in terms of their beneficial eect against microbial gut
infection. They also show a synergistic eect that is normally
higher than any known drug due to their complementary
actions. Since most of these medicinal plants are edible, their
extracts as food product do not have any side eects with
low dosage. Therefore, these products may be very beneficial
for human beings. However, much research is needed to be
put into these studies, as drug regulatory authorities still
have strong regulations against usage of plant extracts as
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... Some essential oils have greater minimum inhibitory concentration (MIC) values for probiotics compared to pathogens. Such a phenomenon makes it possible that both probiotics and essential oil are administered together to treat pathogenic infection in the human gut [75]. They can be combined to form essential oil-flavored fermented milk products, such as flavored curd beverages or flavored yogurt. ...
... The test results can be interpreted as the beverage's capacity for prevention of enteric pathogens [83]. The above examples clearly show that both probiotics and essential oils have a great potential in terms of their beneficial effect against microbial gut infection, and their combined use can afford even more beneficial functional food [75]. ...
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Essential oils (EOs) are mixtures of volatile molecules endowed with health-promoting biological activities that go beyond their role as aromas and natural preservatives and can be exploited to develop functional foods and diet supplements. Their composition is briefly addressed along with regulatory aspects. The potential health benefit of human diet supplementation with EOs is outlined through a review of the recent literature on available clinical trials and preclinical research concerning EOs activity towards: (1) irritable bowel syndrome; (2) inflammatory bowel disease; (3) regulation of microbiota; (4) gastroprotection; (5) hepatoprotection; (6) protection of the urinary tract and diuresis; (7) management of metabolic disorders including hyperglycemia and hyperlipidemia; (8) anti-inflammatory and pain control; (9) immunomodulation and protection from influenza; and (10) neuroprotection and modulation of mood and cognitive performance. The emerging potential in such activities of selected EOs is given focus, particularly green and black cumin, bergamot, orange, myrtle, peppermint, sage, eucalyptus, lavender, thyme, lemon balm, ginger, and garlic.
... As the definition indicates, most intestinal bacteria are essential to the digestive system. Earlier, probiotics were given to animals to improve their health, but later, much research has been put into developing probiotics for human health (Karmakar et al., 2012). The susceptibilities of isolates of Staphylococcus aureus ( Figure 5A, B) and Staphylococcus epidermidis ( Figure 5C, D) were determined against antimicrobial agents and two in combination using the oil. ...
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Integrating sustainability innovation and a circular economy model in extracting freshwater hybrid catfish oil can lead to economic, environmental, and social gains, aligning closely. Fish oil is an industrial product of great nutritional value due to its having long-chain polyunsaturated fatty acids. Moreover, it is highly valued for its prophylactic and therapeutic properties in nutritional and health fields. Moreover, these fatty acids are related to different neuronal functions, and their absence is associated with diverse inflammatory processes and the precarious development of neurons in human patients. Fish oil from the body parts of the hybrid catfish' frozen adipose tissue was extracted using the conventional cooking method, and a screw compressor squeezed the prepared sample and then steamed it to separate solid and oil portions to determine quantitative yield. The GC-MS method characterized the obtained total extracts for the qualitative and quantitative determination of the presence of fatty acids. Oil contents of adipose tissues were saturated fatty acids, monounsaturated fatty acids, and unsaturated fatty acids 37.99±0.41%, 48.43±1.75%, and 13.58±1.33%, respectively. The oil was allowed to examined physical-chemical properties and microbial activities. The results show that the hybrid catfish studied are a rich source of omega-3, omega-6, and omega-9 polyunsaturated fatty acids.
... (16, [20][21][22]. Interestingly, however, EOs displayed limited antibacterial activity against bene cial bacteria such as lactic acid-producing bacteria (23)(24)(25). ...
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Five essential oils (EOs) were previously characterized in vitro and identified as candidate EOs for the development of an intranasal EO spray to mitigate bovine respiratory disease (BRD) pathogens. In the present study, these EOs were evaluated for their potential to (i) reduce BRD pathogens, (ii) modulate nasopharyngeal microbiota, and (iii) influence animal performance, feeding behavior and immune response when administered intranasally to feedlot cattle. Forty beef steer calves (7–8 months old, Initial body weight = 284 ± 5 kg [SE]) received either an intranasal EO spray (ajowan, thyme, fennel, cinnamon leaf, and citronella) or PBS (Control; n = 20/group) on day 0. Deep nasopharyngeal swabs were collected (days − 1, 1, 2, 7, 14, 28 and 42) and processed for 16S rRNA gene sequencing, qPCR, and culturing. Significant effects of EO on community structure (d1), microbial richness and diversity, and relative abundance of some dominant phyla (d1, d2, and d14), and the overall interaction network structure of the nasopharyngeal microbiota were detected. The EO calves had reduced abundance of Mannheimia (4.34% vs. 10.4%) on d2, and M. haemolytica prevalence on d7 as compared to control calves. Feed intake, average daily gain, feeding behavior and blood cell counts were not affected by EO treatment. Overall, a single intranasal dose of EO spray resulted in moderate modulation of nasopharyngeal microbiota and short-term inhibition of Mannheimia while not influencing animal performance, feeding behavior or immune response. Our study, for the first time, shows the potential use of intranasal EO to mitigate BRD in feedlot cattle.
... Different strains exhibit different levels of copolymerization in the presence of different pathogenic bacteria, and the co-aggregation percentage of S. typhi was higher than that of the other strains. The mechanism of inhibition of pathogenic bacteria by probiotics in the human gut was proposed by Shipradeep et al. [42]. Co-aggregation of probiotics and pathogenic microorganisms is considered to be the most important mechanism. ...
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In this study, lactic acid bacteria (LAB) strains were isolated from fermented grains of traditional Chinese Baijiu, and their probiotic properties were characterized. Eleven out of 29 LAB strains showed good tolerance to the gastrointestinal tract and bile salts. The surface characteristics (auto-aggregation, co-aggregation, hydrophobicity), safety (hemolytic and antibiotic sensitivity), antibacterial activity against three foodborne pathogens, and antioxidant and hypoglycemic properties of the 11 LAB strains were investigated. Principal component analysis (PCA) was used to comprehensively evaluate LAB strains and their probiotic properties. It was found that Weissella cibaria (OP288150), Pediococcus acidilactici (OP288151), Pediococcus pentosaceus (OP288154), Pediococcus pentosaceus (OP288156) and Levilactobacillus brevis (OP288158) showed high probiotic properties, with potential for commercial development. The results also demonstrated that fermented grains of Chinese Baijiu can be used as a source of high-quality probiotics.
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The field of probiotics is growing very fast because of its versatile nature and remarkable inherent and biotechnological properties. Probiotics are live microorganisms that confer a health benefit on the host when administered in adequate amounts. Currently, seven genera are used for their probiotics potential. Strains having the desired characteristics are associated with plenty of health benefits. Recent literature shows that different plant and vegetable oils are associated with probiotics. Different reports indicated their various aspects. For instance, the effect of probiotics on plant-based oil, edible oil, and probiotics, the use of oils for probiotics encapsulation etc. are documented. It is also reported that probiotics from vegetable sources and plant oil have some advancements, such as vegetarian and lactose-intolerant people using them. The multidimensional association between probiotics and vegetable oils attracts researchers to explore it in details. This research area is growing fast, but limited research data is available. Hence this literature study was performed to identify the relationship, pros and cons, and provide recent insight in to the literature for the researchers. Materials were collected by searching the related terminologies on different websites finding the downloaded literature and analyzing critically. The results were presented as described by authors and a correlation was found that helps to enhance the field. Collectively, it was found that probiotics and plant and vegetable oils have a multifactorial relationship, and both can increase the effects of one another. The current limitations in the area are the availability of less data and experimental research.
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Dysbiosis of the gut microbiota is associated with the pathogenesis of intestinal diseases such as inflammatory bowel disease, irritable bowel syndrome (IBS), small intestinal bacterial overgrowth (SIBO), and metabolic disease states such as allergies, cardiovascular diseases, obesity, and diabetes. SIBO is a condition characterized by an increased number (>1 × 103 CFU) of abnormal bacterial species in the small intestine. Interest in SIBO has gained importance due to increased awareness of the human microbiome and its potential relationships with human health and disease, which has encouraged new work in this area. In recent years, standard antibiotic regimens (rifaximin and metronidazole) have been used to treat SIBO, but solo antibiotics or their derivatives are insufficient. In this study, the therapeutic effects of the probiotic form, which contains coconut oil and traces of peppermint-lemon-patchouli essential oil, were evaluated on the Dysbiosis-Based Rat SIBO Model. There are significant differences between sick and healthy rats (p = 0.014), between sick rats and rats treated with the oil mix plus probiotic mix protocol (p = 0.026), and between rats treated with only the probiotic and only oil protocols (p = 0.030) in the evaluation of TNF-α levels. Histologically, villi distortion and loss of crypts, epithelial shedding and necrotic changes in the apical regions of the villi, and inflammatory cell infiltrations extending to the lamina propria and submucosa were observed in sick rats. Mitotic figures in villus epithelium and crypts were observed in rats treated with 9.2 × 109 CFU/1000 mg/coconut oil + trace amounts of peppermint-lemon-patchouli essential oil and a probiotic mixture (oil + probiotic mix protocol). A regression of inflammatory reactions and an increase in goblet cells were observed. A decrease was observed in inflammation markers in sick rats. On the other hand, the oil plus probiotic mix protocol recovered digestive system defects in the animals caused by dysbiosis. In the future, these treatment approaches can be effective in the treatment of SIBO.
It is widely known that the use of medicinal plants and probiotics as feed additives has a positive effect on growth, non-specific immune system, and resistance to diseases in aquaculture. This study examines the effects of dietary supplementation with sage (Salvia officinalis) and myrtle (Myrtus communis), alone or in combination with a probiotic mixture (PM) on growth, intestine microflora and histology, some antioxidant enzymes activities in the muscle tissues of rainbow trout (Oncorhynchus mykiss) and disease resistance against Vibrio anguillarum. For this purpose, fish were fed with a control diet of 1% sage, 1% myrtle, 1.1% probiotic mixture, 1% sage +1.1% PM and 1% myrtle+1.1% PM supplemented diets for 60 days. At the end of the trial, the fish fed the diets supplemented with myrtle and sage + PM showed a positive effect on feed conversion ratio. According to the histological assessment, the villi length, villi width and goblet cell numbers in the intestines of fish in all groups increased compared to the control. Superoxide dismutase activity in the muscles of fish in the PM group was higher than the fish in the other groups (p<0.05). The malondialdehyde activity was unaffected with the exception of the fish in the sage group (p<0.05). The lactic acid bacteria count in the intestines increased in fish fed the sage + PM (p<0.05). Fish fed the diets supplemented with sage + probiotic mixture, probiotic mixture, myrtle + probiotic mixture, and myrtle saw a significant reduction in mortality (0-32.5%) due to V. anguillarum compared to the control (63.2%) (p<0.05). In conclusion, the use of probiotics, sage and myrtle in combination as a feed supplement showed a positive effect on the growth performance, intestinal microflora and histology, and antioxidant enzymes activities and disease resistance in rainbow trout.
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This study aimed to evaluate the application of encapsulated L. plantarum and eugenol as potential biocontrol agents in sliced apples. The combined encapsulated L. plantarum and eugenol treatment was more effective than separate encapsulated L. plantarum and eugenol treatments, with regards to browning inhibition and consumers panel test. The application of encapsulated L. plantarum and eugenol reduced the decline of the physicochemical qualities of the samples, and improved the ability of antioxidant enzymes to scavenge reactive oxygen species. Furthermore, reductions in the growth of L. plantarum of only 1.72 log CFU/g were observed after 15 days of storage at 4°C for samples treated with encapsulated L. plantarum and eugenol. Results suggest the combined encapsulated L. plantarum and eugenol appears to be a promising method to protect fresh-cut apples from food-borne pathogens while maintaining the visual appearance.
The use of essential oils (EOs) as a natural alternative to antibiotics for disease prevention strategies is gaining much interest in recent decade. Coriander (Coriandrum sativum L.) essential oil is rich in bioactive compounds like linalool and geranyl acetate which have antioxidant, anti-inflammatory and antimicrobial activities. The present work was proposed to evaluate the inclusion levels of coriander oil in tilapia feed to enhance tilapia health and resistance to bacterial infection. Five iso-nitrogenous and iso-lipidic feeds were prepared with graded levels of coriander oil (0, 0.5, 1, 1.5 and 2%). The fish were then fed with the five experimental diet twice daily for a period of 60 days in triplicate. Haemoglobin, mean corpuscular volume, mean cell haemoglobin increased significantly in the coriander oil treated groups. The thrombocyte count was more in 2% inclusion level. The superoxide dismutase activity increased significantly in all the treated groups. The feeds with 1.5 and 2% coriander oil showed increased respiratory burst and myeloperoxidase activities while lysozyme and antiprotease activities were significantly higher in 1, 1.5 and 2% dietary treatments compared to control. The survival increased in dose dependent manner post challenge with an intraperitoneal injection of Aeromonas hydrophila at a LD50 dose of 5 × 106 cfu mL-1. The feed containing 1, 1.5 and 2% of coriander oil showed 89, 100 and 100% survival respectively compared to 39% in control diet. The expression level of IgM and IL-8 increased significantly post challenge with A. hydrophila in coriander oil fed groups. The expressions of TNFα, IL-1β, TGFβ and HSP 70 genes, however, decreased significantly in the treated groups compared to control. Histopathological examination of spleen showed large melano-macrophage centers in control and 0.5% coriander fed group with signs of necrosis and vacuolation post A. hydrophila infection, whereas 1, 1.5 and 2% treated groups showed normal architecture of spleen. From the above observations it can be concluded that coriander oil with 1% incorporation in feed improves tilapia health and resistance to bacterial infection.
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Colorectal cancer is one of the most frequently diagnosed forms of cancer, and the therapeutic solutions are frequently aggressive requiring improvements. Essential oils (EOs) are secondary metabolites of aromatic plants with important pharmacological properties that proved to be beneficial in multiple pathologies including cancer. Mentha piperita L. (M_EO) and Rosmarinus officinalis L. (R_EO) essential oils are well-known for their biological effects (antimicrobial, antioxidant, anti-inflammatory and cytotoxic in different cancer cells), but their potential as complementary treatment in colorectal cancer is underexplored. The aim of the present study was to investigate the M_EO and R_EO in terms of chemical composition, antioxidant, antimicrobial, and cytotoxic effects in a colorectal cancer cell line—HCT 116. The gas-chromatographic analysis revealed menthone and menthol, and eucalyptol, α-pinene and L-camphor as major compounds in M_EO and R_EO respectively. M_EO exhibited potent antimicrobial activity, moderate antioxidant activity and a low cytotoxic effect in HCT 116 cells. R_EO presented a significant cytotoxicity in colorectal cancer cells and a low antimicrobial effect. The cytotoxic effect on non-cancerous cell line HaCaT was not significant for both essential oils. These results may provide an experimental basis for further research concerning the potential use of M_EO and R_EO for anticancer treatment.
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The Probiotics are the live feed supplements basically in the form of microorganisms that cause potential benefit to health. It is implicit in the definition that consumption of the probiotics beneficially affects the intestinal microflora. It has been reported of utilization of Probiotics in curing severe gastronomical diseases. The basic facility of producing Probiotics is that it does not require high input, and thus can be produced at a cheaper cost. Microorganism can be grown with minimal food nutrients and can be used to harvest a lot of output in terms of nutritional value and other medicinal benefits. The biggest challenge to use live feed supplement for human is the fear of antibiotic resistance transference to the gut flora. The evaluation of existing strains to develop a strong probiotic product is important because it is difficult to enhance the strains genetically which uses antibiotic resistance as a marker for selection of the modified strains. The present investigations are to identify the various bacterial strains commonly present in daily food materials and to evaluate their probiotic potential in-vitro. Specifically, the strains were isolated from ice cream, curd and milk for developing safe probiotic strains. The strains were identified, characterized and named as SJ1 (Streptococcus lactis), SJ2 (Bacillus coagulans) , SJ3 (Lactobacillus casei) and SJ5 (Bifidobacterium bifidum). One more strain, Streptococcus thermophilus (NCIM 2412) was procured and tested for its probiotic potential as reported in various existing studies. Probiotic parameters such as acidity tolerance, bile tolerance, lactic acid production, adherence capability and phenol tolerance were evaluated. The strains were also passed through an artificial simulation of gastronomical pathway to ensure their survivability in the harsh in-vivo conditions. Minimal antibiotic resistance is an important factor that was tested on all strains isolated so as to minimize the antibiotic resistance transference to the already existing gut flora. Out of the above mentioned strains, Streptococcus thermophillus, Streptococcus lactis and Bifidobacterium bifidum showed a great potential to be developed as Probiotics. Probiotics is the next generation product of biochemical engineering with enormous scope in studies and commercial utilization.
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Urinary tract infections are common type of pathogenic infections in body. Essential oils of Coleus aromaticus and two varieties of Ocimum sanctum (Rama Tulasi and Shyama Tulasi) were compared for antibacterial activity against urinary tract infection (UTI) causing bacteria; Staphylococcus aureus, Klebsiella oxytoca, Proteus vulgaris, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus mirabilis. Ocimum sanctum (Rama Tulasi) and Coleus aromaticus oils showed remarkable activity, later being more active. Least activity was observed in Shyama Tulasi variety of Ocimum sanctum. Constituents of the oils were analyzed by GC-MS and GC-FID. The essential oils have promising inhibitory effect with minimal inhibitory concentration (MIC) ranging from 0.5μl/ml -6μl/ml. The essential oils of two varieties of Ocimum sanctum have differences both in chemical composition and MIC values against UTI infection causing pathogens.
Properly formulated probiotic-containing foods offer consumers a low risk, low cost dietary component that has the potential to promote health in a variety of ways. Several such products are available commercially, although markets in Japan and Europe are more developed than in the USA. Once healthful attributes of a probiotic product have been identified, there remain microbiological, product, regulatory and labeling issues to be addressed prior to marketing. Microbiological and product issues include safety, effective scale-up for manufacturing, definition of probiotic activity, probiotic stability in the product over the course of product manufacture, shelf-life and consumption, definition of effective dose and target population(s), and development of quality assurance approaches. Examples of probiotic-containing foods are given. Regulatory and labeling issues are complicated because they differ for each country, but are likewise critical because they provide the means for communication of the product benefits to the consumer. The regulatory climate worldwide appears to be one of caution about overstating the benefits of such products but at the same time not preventing corporate commitment to marketing.
The aim of this work was to investigate the antimicrobial activity of twelve essential oils, against Gram-positive and Gram-negative bacteria, for a potential use in food industry. The antimicrobial activity of essential oils was determined by an agar diffusion method against foodborne pathogens and spoilage bacteria. Further, bacteriostatic and bactericidal concentrations were determined for each strain that evidenced sensitivity to the oils. All the oils showed bacteriostatic and bactericidal activity against Escherichia coli O157:H7 and Salmonella Typhimurium, while Brochotrix thermosphacta was inhibited by eight of 12 tested oils. Finally, the pathogenic microorganism Listeria monocytogenes and lactic acid bacteria strains were affected only by thyme, oregano and vervain oils. The essential oils considered in this research showed a satisfactory antimicrobial activity. The essential oils could be used for the development of novel systems for food preservation.
Probiotic microbial feed supplements are gaining wide acceptance in livestock production, and may be applicable to aquaculture production systems. The present study was conducted to examine probiotic treatment in the fingerling diet of Nile tilapia Oreochromis niloticus (L.). A total of 240 of Nile tilapia fingerlings (weight ranged from 22.96 to 26.40 g) were divided into five experimental groups. The experiment was conducted for 120 days. Experimental diets were identical in all, except for the variation in probiotic levels. A probiotic (Biogen®) was used at 0% (diet 1), 0.5% (diet 2), 1.5% (diet 3), 2.0% (diet 4) and 2.5% (diet 5) inclusion rates in the experimental diets. The growth performance and nutrient utilization of Nile tilapia including weight gain, specific growth rate, protein efficiency ratio, protein productive value and energy retention were significantly (P≤0.01) higher in the treatment receiving probiotic (Biogen®) than the control diet. No differences were observed for moisture, ash and protein content (P≤0.01) among the experimental diets. The lowest gross energy and lipid contents were recorded for fish fed the diet containing 0.5% Biogen® (P≤0.01). The production performance and subsequent cost–benefit analyses clearly indicated that the diets containing probiotic biogen recorded the highest net return and the lowest total cost compared with the control diet.
Lactobacillus sake CTC494 isolated from a naturally fermented sausage, produced an antibacterial agent active against selected strains of Listeria monocytogenes and L. innocua. The agent was bacteriolytic against L. monocytogenes and sensitive to proteolytic enzymes; it was identified as a bacteriocin and was designated as sakacin K. The ability of Lact. sake CTC494 to inhibit the growth of listeria, compared to a bacteriocinogenic negative control strain, was examined in a model sausage system and in dry fermented sausages. In dry fermented sausages Lact. sake CTC494 was able not only to suppress the growth of listeria but to diminish their number by 1.25 log compared to the non-bacteriocinogenic control strain. Thus, Lact. sake CTC494 has proved to be a good starter culture providing good organoleptical and sensorial qualities to the product and can be employed as a bioprotective starter culture in fermented meat products.
A kinetic model of the fermentative production of lactic acid from glucose by Lactococcus lactis ssp. lactis ATCC 19435 in whole-wheat flour has been developed. The model consists of terms for substrate and product inhibition as well as for the influence of pH and temperature. Experimental data from fermentation experiments under different physical conditions were used to fit and verify the model. Temperatures above 30 °C and pH levels below 6 enhanced the formation of by-products and d-lactic acid. By-products were formed in the presence of maltose only, whereas d-lactic acid was formed independently of the presence of maltose although the amount formed was greater when maltose was present. The lactic acid productivity was highest between 33 °C and 35 °C and at pH 6. In the concentration interval studied (up to 180 g l−1 glucose and 89  g l−1 lactic acid) simulations showed that both substances were inhibiting. Glucose inhibition was small compared with the inhibition due to lactic acid.