Article

Bactericidal Activity of Lemon Juice and Lemon Derivatives against Vibrio Cholerae.

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Food products can be possible vectors of the agent responsible for cholera epidemics, because some of these products allow Vibrio cholerae O1 to develop to concentrations above the dangerous level. This study deals with the behaviour of essential oils, natural and concentrated lemon juice and fresh and dehydrated lemon peel against V. cholerae O1 biotype Eltor serotype Inaba tox+. Our aim was to evaluate whether these products, used at different dilutions, exhibit bactericidal or bacteriostatic activity against the microorganism, when present at concentrations of 10(2), 10(4), 10(6) and 10(8) colony forming units (CFU) ml(-1), and after different exposure times. 10(8) CFU ml(-1) was considered an infectious dose. Concentrated lemon juice and essential oils inhibited V. cholerae completely at all studied dilutions and exposure times. Fresh lemon peel and dehydrated lemon peel partially inhibited growth of V. cholerae. Freshly squeezed lemon juice, diluted to 10(-2), showed complete inhibition of V. cholerae at a concentration of 10(8) CFU ml(-1) after 5 min of exposure time; a dilution of 2 x 10(-3) produced inhibition after 15 min and a dilution of 10(-3) after 30 min. It can be concluded that lemon, a natural product which is easily obtained, acts as a biocide against V. cholerae, and is, therefore, an efficient decontaminant, harmless to humans.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... It has been used in some cases to prevent the mouth thirst of patients in hospitals [2]. Furthermore, it has been reported to have antimicrobial activity [3] and confirmed effective against Vibrio cholerae [4,5]. Therefore, lemon juice is considered effective for disinfection of drinking water [6]. ...
... Previously, we reported the possibility that lemon juice could suppress an increase in blood pressure [12]. Furthermore, various studies have reported the antibacterial activity of lemon juice [3][4][5][6][7][8][9][10]. However, we could not find previous studies wherein in vivo experiments were conducted to evaluate the effectiveness of lemon juice as an oral rinsing agent. ...
... Nevertheless, the decrease in pH might have inhibitory effects on microbial contamination [28], hence can contribute to a possible increase in shelf stability. However, it can also have a significant effect on product quality particularly in terms of taste. ...
Article
Full-text available
This study investigated the effects of brine solution pre-treatment and addition of calamansi juice extract on oyster mushroom kropek sensory and physicochemical (pH, color, moisture, water activity) properties. Results revealed, that the pre-treatment and addition of calamansi juice extract significantly affected (p<0.05) the appearance (3.44 ±1.43-5.21 ±1.71), salty taste (3.35 ±2.29-4.92 ±2.17), sour taste (2.51 ±1.98-5.42 ±2.51), and spicy taste (2.98 ±2.35-4.56 ±2.60) of the kropek. The acceptability test also revealed a significant difference (p<0.05) on product appearance (7.09 ±1.22-7.47 ±1.46) and overall acceptability (6.40 ±1.18-7.18 ±1.07). Although, in terms of consumer preference, no differences were noted among sample ranks (p>0.05). However, treatment 1 was chosen as the most preferred since it had the lowest rank among samples, hence was subjected to laboratory tests along with the control. Physicochemical tests revealed a significant decrease (p<0.05) in the pH of both raw (6.17 ±0.02-4.17 ±.01) and cooked (7.01 ±0.02-5.44 ±0.02) kropek with the increased amount of calamansi juice extract. Also, color parameters such as L* (67.03 ±0.84-71.60 ±1.04), a* (5.63 ±0.55-9.30 ±0.36), b* (21.90 ±0.62-24.07 ± 0.55) and Hue° (1.20 ±0.01-1.32 ±0.02) values were affected significantly. Generally, the increase in brine solution and calamansi juice extract resulted in a lighter color (red-yellow), as displayed by treatment 4 (15% brine and 20ml calamansi juice extract), although treatment 3 (15% brine and 20ml calamansi juice extract) exhibited darker color. Nevertheless, the moisture content (1.08 ±0.07-1.13 ±0.35) and water activity (0.53 ±0.09-0.54 ±0.01) of the most preferred sample and the control were considered low and not significantly different (p>0.05), indicating longer shelf stability. Therefore, results of this study are important as they give baseline information about the effect of pre-treatment and addition of calamansi juice extract on product key parameters that would help solve problems during its processing, preservation, storage, distribution, and even food consumption. However, it is recommended that further studies may be conducted, particularly in terms of the correlation of some physicochemical properties with the results of sensory tests.
... Similar studies have reported that the functional foods propolis and lemon juice are also proven to have antibacterial activity. 32,33 The results in this study suggest that SFB may act as a functional food to maintain human health and prevent infections. ...
Article
Full-text available
Soybean fermentation broth (SFB) exhibits potent antibacterial activity against different species of bacteria in in vitro assays and animal models. Four isoflavone compounds-daidzin, genistin, genistein, and daidzein-of SFB were analyzed and quantified by high-performance liquid chromatography. In the in vitro test, daidzin and daidzein had more potent antibacterial activity than genistin. The minimum inhibition concentration values for these bacteria of SFB ranged from 1.25% to 5%, and the minimum bactericidal concentration values of strains ranged from 2.5% to 10%, depending on the species or strain. Vancomycin-resistant Entercoccus faecalis (VRE) strains were also tested for susceptibility to SFB in two species of animal model: the Sprague-Dawley rat and the BALB/c mouse. SFB-fed Sprague-Dawley rats showed excellent elimination efficiency against VRE, close to 99% compared with the phosphate-buffered saline-fed control group. In the BALB/c mouse model, SFB antibacterial activity was 65-80% against VRE compared with the control. In conclusion, SFB contains natural antibacterial substances such as daidzin, genistin, and daidzein that inhibit bacterial growth.
... In particular, its gingerol-related components have been reported to possess antimicrobial and antifungal properties, as well as several pharmaceutical properties [20] . The garlic and ginger is popular as plants and food ingredient for flavouring and adding acidity, its juices have been reported to exhibit antibacterial activity against wide range of microbes including K. pneumoniae, Shigella flexnerii, E. coli ATCC 25922 and Vibrio cholerae [21,22] . The MIC values of crude extracts and garlic cloves were 65.50, 110.80, 58.50, 89.00, 160.20, 78.90 and 80.10 毺g/mL against E. coli, Enterobacter sp., P. aeruginosa, Proteus sp., Klebsiella sp., S. aureus and Bacillus sp., respectively ( Table 4). ...
Article
Full-text available
To evaluate the antibacterial properties of Allium sativum (garlic) cloves and Zingiber officinale (ginger) rhizomes against multi-drug resistant clinical pathogens causing nosocomial infection. The cloves of garlic and rhizomes of ginger were extracted with 95% (v/v) ethanol. The ethanolic extracts were subjected to antibacterial sensitivity test against clinical pathogens. Anti-bacterial potentials of the extracts of two crude garlic cloves and ginger rhizomes were tested against five gram negative and two gram positive multi-drug resistant bacteria isolates. All the bacterial isolates were susceptible to crude extracts of both plants extracts. Except Enterobacter sp. and Klebsiella sp., all other isolates were susceptible when subjected to ethanolic extracts of garlic and ginger. The highest inhibition zone was observed with garlic (19.45 mm) against Pseudomonas aeruginosa (P. aeruginosa). The minimal inhibitory concentration was as low as 67.00 µg/mL against P. aeruginosa. Natural spices of garlic and ginger possess effective anti-bacterial activity against multi-drug clinical pathogens and can be used for prevention of drug resistant microbial diseases and further evaluation is necessary.
... Extracts from several plants and fruits have been shown to inhibit the growth of V. cholerae. Examples include lemon essential oils and extracts of fresh lemon peel (Castillo et al., 2000); ethyl acetate and ethanol extracts of several varieties of Piper betle (Shitut et al., 1999);extracts of Allium sativum, Camelia sinensis and Chamaesyca hirta (Vijaya and Ananthan, 1996); Terminalia avicennoides (Alkinsinde and Olukoya, 1995); black tea, Japanese green tea and chinese tea and coffee (Shetty et al., 1994); infusion and decoction of Punica granatum (Guevara et al., 1994). However, our findings represent the first report of a plant extract that inhibits the growth, enterotoxin production, and adhesion of V. cholerae to CHO cells. ...
Article
The effects of Haematoxylon brasiletto extracts on growth, enterotoxin production, and adhesion of V. cholerae O1 and O139 to Chinese Hamster Ovary (CHO) cells were determined. The minimal bactericidal concentration (MBC) for growth was 0.3–0.4 mg mL. No enterotoxin formation was detected when lower concentrations (50% or 75% of the MBC) of H. brasiletto extracts were added to the media. Pre-exposing bacteria and CHO cells to various concentrations of extracts affected the adhesion between bacteria and CHO cells. Partial purification of the active fraction suggested that polyphenols may play a role in the antimicrobial activity exhibited by H. brasiletto extracts.
... These salad dressings may provide a harsh environment for foodborne pathogens such as Salmonella, Escherichia coli O157:H7, L. monocytogenes, or Staphylococcus aureus to survive, due to the presence of acetic or citric acids as low pH ingredients, salt, and preservatives such as sorbic and/or benzoic acid (Beuchat et al., 2006). Antimicrobial effects of salad dressings, including Ranch, Thousand Island, olive oil, lemon juice and vinegar has been well documented (Weagant et al., 1994;Entani et al., 1998;Castillo et al., 2000;Ciafardini and Zullo, 2002;Vijayakumar and Wolf-Hall, 2002;Beuchat et al., 2006). This leads to the hypothesis that exposing foods to salad dressings prior to consumption may control transmission of foodborne pathogens. ...
Article
This study evaluated the antilisterial effects of salad dressings, as well as oils mixed with lemon juice or vinegar, on frankfurters during simulated home storage, without or with prior microwave oven heating. Frankfurters were inoculated (2.4±0.1 log CFU/cm2) with Listeria monocytogenes (10-strain mixture) and stored aerobically in bags at 7 °C. At 0, 7 and 14 days, frankfurters were immersed (5 or 20 min, 25±2 °C) in sunflower oil plus lemon juice or vinegar, extra virgin olive oil plus lemon juice or vinegar, or salad dressings (i.e., Vinaigrette, Ranch, Thousand island, and Caesar), or distilled water (DW), without or with prior microwave oven heating (1100 Watts, 2450 MHz, high power) for 30 s. Samples were analyzed for microbial growth during storage, and survivors following application of treatments, on tryptic soy agar plus 0.6% yeast extract and PALCAM agar. Immersion in salad dressings and in the combinations of oils with lemon juice or vinegar caused significant (P<0.05) reductions of L. monocytogenes, compared to dipping in DW. Reductions increased with previous product storage, from 0.5–0.9 (day-0) to 1.2–2.1 (day-14) log CFU/cm2, as levels of contamination also increased. Reductions of pathogen counts by each treatment increased (P<0.05) when applied following exposure to microwave oven heating; ranging from 1.2–1.9 (day-0) to 2.2–3.3 (day-14) log CFU/cm2. Reductions were not (P≥0.05) different between 5 and 20 min of immersion in most treatments. In general, the reduction effects of salad dressings decreased in the order of sunflower or extra virgin olive oil plus vinegar ≥ sunflower or extra virgin olive oil plus lemon juice > Caesar ≥ Thousand island ≥ Ranch ≥ Vinaigrette. The results of the present study indicated that salad dressings and oils with lemon juice or vinegar may contribute to control of L. monocytogenes on ready-to-eat meat products in the home environment, especially when these products are treated and used in salads.
... Nogueira et al. (19) reported less effective inactivation of E. coli O157:H7 in lime than in lemon juice concentrates. In other studies, fresh squeezed lemon juice, lemon concentrates, and some lemon derivatives inactivated to various degrees pathogens such as Salmonella (16,25,28) and V. cholerae (8,9,31). Under some circumstances, lime juice consumption was encouraged to prevent foodborne transmission during cholera outbreaks (26). ...
Article
Full-text available
Survival of a five-strain mixture of stationary phase (nonadapted) and acid-adapted Escherichia coli O157:H7 in single-strength lemon and lime juices was evaluated at room temperature (22 degrees C). The juices were reconstituted from concentrates that contained no preservatives and intrinsic pH values of 2.5 to 2.6 and titratable acidities of 4.51 to 4.53% (wt/vol, citric acid). A greater than 5-log reduction of stationary-phase cells was achieved in both lemon and lime juices after 72 h of incubation. Similar log reductions were obtained when the reconstituted juices were adjusted to pH 2.7, which is above the highest value normally observed in juice processing plants during the reconstitution of single-strength lemon or lime juice from concentrates. Lemon juice had a significantly higher inhibitory effect (P < 0.05) on E. coli O157:H7 than did lime juice. Validation tests with commercially produced shelf-stable lemon and lime juices confirmed that storage of the juices at room temperature (22 degrees C) for 3 days may be an alternative to heat treatment to ensure the 5-log reduction of vegetative pathogens of concern required for the products under the U.S. Food and Drug Administration juice hazard analysis and critical control point regulations.
... The lethal effect was evident within 5 min of exposure to lime juice. (Castillo et al., 2000) reported that concentrated lemon juice and essential oils inhibited V. cholerae completely at all studied dilutions and exposure times. ...
Article
Full-text available
The antimicrobial effect of crude extract of lime ( Citrus aurantifolia ) was assayed against different bacterial species by agar well diffusion method. The highest inhibition zone of 28 mm was observed in Vibrio cholerae followed by Enterobacter species (9mm), Citrobacter species (8mm) and Escherichia coli (8mm). Shigella , Salmonella and Klebsiella species were found resistant. So the study was mainly focused on V. cholerae . Different concentrations of the crude extract such as 75%, 50%, 25% and 5% were tested to calculate the minimum amount that inhibits the bacteria which showed the zone of inhibition (ZOI) as 31mm, 24mm, 17mm and 9mm respectively. The minimum bactericidal concentration (MBC) ranged from 6.25 mg/l to 50 mg/l. This result suggests that citrus fruit like limes are effective in preventing infection with Vibrio species. Key words: Agar well; Crude extract; Minimum bactericidal concentration; Zone of inhibition. DOI: 10.3126/sw.v8i8.3847 Scientific World Vol.8(8) 2010 pp.44-46
... Lower pH of fruit and ultimately the raw juice have inhibitory effects to microbial contamination (Castillo et al., 2000;Rodrigues et al., 2000). However, during the processing, a large part of the quality characteristics of the fresh fruits undergo remarkable changes which could reduce the nutritional value of the products (Wenkam, 1990;Landon, 2007). ...
Article
Fresh fruit juice is an essential component of human diet and there is considerable evidence of health and nutritional benefits. However, nature of the fruits used in juicing and unhygienic processes in the value chain may cause poor quality of juice. This cross-sectional study was conducted to assess physicochemical characteristics and hygienic practices along the value chain of raw fruit juice vended in Dar es Salaam, Tanzania. A total of 90 juice vendors were interviewed. Ninety juice samples were collected and analysed for physicochemical quality. The pH of juices ranged between 2.7 and 6.4, acidity 0.01% and 1.3% and, total soluble solids ranged between -1.5 and 18.04 ⁰Brix. Most juices (67.8%) had ⁰Brix levels below Codex recommended values classified as weak and watery. Juices were made of mango, passion, tamarind, sugar cane and mixture of these fruits sourced from open markets in the city. Water for washing of fruits and dilution of juices was from deep wells (53.3%) and taps (46.7%). About one third (37.8%) of the juice vendors didn’t wash the fruits before juicing and 44.4% didn’t boil water for juice dilution. Juice extraction was done by kitchen blenders, boiling in water and squeezing by simple machines. Juice pasteurization was not done. The majority of vendors (78.9%) stored juices in plastic buckets and juice was sold in glass cups, reused plastic bottles and disposable cups. Vending sites were restaurants, bus stands and along roadsides. The majority of premises (78.9%) were in unhygienic condition that likely encouraged or introduced contaminants to the juices. It is concluded that, the overall handling, preparation practices and physicochemical quality of raw fruit juices vended in Dare es Salaam City are poor. The government should educate the vendors on food safety and hygiene as well as enforcing regular monitoring of the quality of street fruit juices.
... Fresh lemon peel and dehydrated lemon peel partially inhibited growth of V. cholerae. Freshly squeezed lemon juice, diluted to 10 -2 , showed complete inhibition of V. cholerae at a concentration of 10 8 CFU/ ml after 5 min of exposure time; a dilution of 2 x 10 -3 produced inhibition after 15 min and a dilution of 10 -3 after 30 min [110]. ...
... In screening of lemon and orange oil by disc diffusion method, the diameters of inhibition zone were found to be 50 and 20 mm which were greater than inhibition zone of reference antibiotics, gentamycin 16.5mm and streptomycin 17 mm. Minimum inhibitory concentrations (MIC) of lemon and orange oil against M. furfur were found to be 0.8 and 2.2 μl/ml (104) . ...
... 1,2 SUD (Morton 1981). Species from the genus Citrus have well known antimicrobial properties (de Castillo et al. 2000; Prabuseenivasan et al. 2006). To-nzu, Cebolla Allium cepa L. ...
Article
Objectives: Little is known about the interface of traditional (generally plant based) medicines and of commercially available pharmaceutical (and related) products. Here we provide a case study to understand how and to what extent traditional and modern medicine have been integrated in an indigenous community and whether these two categories offer a meaningful model for understanding medicine selection. Consequently, this paper explores the use and knowledge of medicinal plants and patent medicines among laypeople living in a rural Mazatec indigenous community in Oaxaca, Mexico. Methods: This paper is based on field study over a period of approximately 20 months using participant observation, unstructured and structured interviews including freelisting. The medicinal plant species and commercially available pharmaceuticals were assessed using published biomedical information. Main outcomes: The local ethnopharmacopoeias, emic concepts of illness, epidemiology, and case studies on therapeutic choice were documented. We found that self-treatment is the most common first therapeutic choice. Many of the plant species used by Mazatecs have recognized therapeutic properties, in some cases in vivo and in vitro studies point to well defined pharmacological effects, and in a few cases clinical evidence is available. Likewise, people commonly use patent medicines that are effective in the treatment of the most common health conditions. However, we also documented the medicinal use of some toxic plant species (Aristolochia spp.) and of some patent medicines that are held to be unsafe in developed countries (sodium metamizole). Conclusions: When looking at a complex pluralistic medical system an approach that goes beyond the externally imposed dichotomic categories of traditional and modern medicine can be very useful to shed light on other dimensions that underlie the local use of medicines. With the increasing integration of the Mazatecs with the outside world, the concomitant use of both types of resources is constantly changing and helps the Mazatecs in their struggle for health.
... The maximum antimicrobial activity was exhibited by acetone, ethanol, methanol and distilled water extract of the fruits against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Shigella shigella. Whereas petroleum ether extract is less effective against the test strains [205]. ...
Article
Full-text available
Medicinal plants possessed antibacterial activities via many mechanisms, such as disruption of cytoplasmic membrane, inhibition of cell wall synthesis, inhibition of cell membrane synthesis, inhibition of nucleic acid synthesis, inhibition of energy metabolism, as well as inhibition of bacterial virulence factors, including quorum-sensing signal receptors, enzymes and toxins. Evidence of these molecular effects at the cellular level include inhibition of biofilm formation, inhibition of bacterial attachment to host ligands, and neutralisation of bacterial toxins. The current review highlighted the medicinal plants showed antibacterial activity with their spectrum and mechanisms of action.
... From HPTLC analysis it is reported that the major phytochemical present in the crude extract of P. nigrum was found to be piperine thus the inhibitor effect of crude extract of P. nigrum and its active constituent was found to be piperine [34]. C. aurantifolia is popular as fruit and food ingredient for flavoring and adding acidity, its juices have been reported to exhibit antibacterial activity against wide range of microbes including Klebsiella pneumoniae, Shigella flexnerii, E. coli ATCC 25922 and Vibrio cholerae [35,36]. The antimicrobial potency of plants is believed to be due to tannins, saponins, phenolic compounds, essential oils and flavonoids [37]. ...
Article
Full-text available
Spices traditionally have been used as coloring agents, flavoring agents, preservatives, food additives and medicine in Bangladesh. The present work aimed to find out the antimicrobial activity of natural spices on multi-drug resistant Escherichia coli isolates. Anti-bacterial potentials of six crude plant extracts (Allium sativum, Zingiber officinale, Allium cepa, Coriandrum sativum, Piper nigrum and Citrus aurantifolia) were tested against five Escherichia coli isolated from potable water sources at kushtia, Bangladesh. All the bacterial isolates were susceptible to undiluted lime-juice. None of them were found to be susceptible against the aqueous extracts of garlic, onion, coriander, pepper and ginger alone. However, all the isolates were susceptible when subjected to 1:1:1 aqueous extract of lime, garlic and ginger. The highest inhibition zone was observed with lime (11 mm). Natural spices might have anti-bacterial activity against enteric pathogens and could be used for prevention of diarrheal diseases. Further evaluation is necessary.
Article
Vibrio cholera is a major foodborne pathogen in Thailand. It is present in raw and lightly cooked foods, and it causes cholera. Natural products inhibiting it can be used to improve the safety of foods. In this study, elephant garlic oil was studied for its major diallyl sulfide content and its antimicrobial activity against V. cholerae. The oil had a very low concentration of diallyl monosulfides (1.62%) in comparison with the other diallyl sulfides (25.09% for diallyl disulfide, 16.04% for diallyl trisulfide, and 10.58% for diallyl tetrasulfide). In an in vitro study, the oil was found to have a bacteriocidal effect on all tested strains of V. cholerae, with varied minimal inhibitory concentrations (MICs) ranging from 3.13 to 25 microg/ml. It was also found that elephant garlic oil retarded the growth of the bacteria or reduced the bacterial cell load in the food model, depending on its concentration.
Article
Citrus genus is the most important fruit tree crop in the world and lemon is the third most important Citrus species. Several studies highlighted lemon as an important health-promoting fruit rich in phenolic compounds as well as vitamins, minerals, dietary fiber, essential oils and carotenoids. Lemon fruit has a strong commercial value for the fresh products market and food industry. Moreover, lemon productive networks generate high amounts of wastes and by-products that constitute an important source of bioactive compounds with potential for animal feed, manufactured foods, and health care. This review focuses on the phytochemistry and the analytical aspects of lemon compounds as well as on the importance for food industry and the relevance of Citrus limon for nutrition and health, bringing an overview of what is published on the bioactive compounds of this fruit.
Article
To determine the effect of lime juice on the estrous cycle and ovulation of cyclic female rats. Twenty-five adult female Sprague-Dawley rats were used. The study was divided into 2 experiments (I and II). In experiment I, 15 rats were randomly subclassified into 3 groups (Ia, Ib, and Ic) of 5 rats each. The estrous cycles of the rats were studied for the first 16 days to establish cyclicity, after which lime juice was administered by gastric gavage for the next 24 days. Rats in group Ia received 1 mL of undiluted lime juice, rats in group Ib received 1 mL of 50% diluted lime juice, and rats in group Ic (control animals) received only distilled water. In experiment II, 10 female rats were used and were categorized into 2 groups (IIa and IIb), with 5 rats in each group. Rats in group IIa received 1 mL of undiluted lime juice during the morning of proestrus, and those in group IIb received only distilled water on the day of proestrus. The rats were killed the next day with use of chloroform anesthesia. The upper parts of the oviducts were excised and examined under the light microscope for assessment of the number of ova shed. There was an irregular pattern in all phases of the estrous cycle of 100% of the rats given undiluted lime juice and in 80% of those given 50% diluted lime juice. There was a significant (P = .001) reduction in the number of ova shed in rats administered undiluted lime juice in comparison with the control animals. Ovulation was partially blocked, as shown by the reduced number of ova observed in the oviducts from the rats given undiluted lime juice (5.10 +/- 2.37) in comparison with the control rats (12.70 +/- 1.14). In rats, lime juice causes irregularity of the estrous cycle, partially blocks ovulation, and may possibly compromise fertility.
Article
To evaluate the effects of fresh lime, lemon, grapefruit, and pummelo juices on the transport of digoxin, a P-glycoprotein (P-gp) substrate, in Caco-2 cell monolayers. Bidirectional [3H]-digoxin fluxes across confluent Caco-2 cell monolayers were determined in 0-50% fruit juices at pH 7.4. Verapamil HCl (100 microM) served as positive control. Juice toxicity was evaluated by the 3-(4,5 dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay. Apical-to-basal (A-to-B) digoxin flux was enhanced by 50% fruit juice in the order of lemon > lime > pummelo > grapefruit. The four fruit juices could be divided into two groups based on their effects on transepithelial electrical resistance (TEER), viability, and digoxin transport activity of the Caco-2 cells. Grapefruit and pummelo juices produced similar digoxin transport profiles that were characteristic of those observed with P-gp inhibitors. Both juices decreased net digoxin efflux by 1.2 U per 10% increase in juice concentration and had a propensity to increase cellular TEER at high concentrations (>30%). However, cellular TEER and viability decreased with increasing concentration of lime and lemon juices. Both juices also produced similar digoxin transport profiles, the A-to-B and B-to-A digoxin Papp increasing with increasing juice concentration above 5%. Net digoxin efflux was 30% of control value and relatively independent of juice concentration. These results paralleled the groupings of the four fruits according to their prominent flavonoid pattern and taxonomy. The effects of lime, lemon, grapefruit, and pummelo juices on the TEER, viability, and digoxin transport activity of the Caco-2 cells appeared to be dependent on the dominant flavonoid pattern and taxonomy of the citrus fruits.
Article
Introduction: Antimicrobial activity of fruit juice and ethanolic extracts of root, leaf, bark, peel and pulp of citron (Citrus medica Linn., Rutaceae) was examined against seven bacteria (Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Proteus vulgaris), two fungi (Aspergillus flavus and A. niger) and a yeast Candida albicans of clinical origin. Methods: The level of antimicrobial effects was established using an in vitro disc diffusion method; minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined by standard agar dilution method. Results: All extracts and fruit juice showed varied level of antibacterial activity against one or more test bacteria. Antifungal activity was shown by only root extract and fruit juice while C. albicans was resistant to all tested plant samples. Broad spectrum antimicrobial activity was shown by fruit juice (MIC <1% to 3.5% and MBC 1% to 7% v/v) and fruit pulp (MIC 25 mg/ml and MBC 30 to 75 mg/ml). Root extract was found highly potent with MIC as small as 0.5 mg/ml and MBC 1 mg/ml against S. aureus. Among all tested plant samples leaf and peel extracts have shown less antimicrobial activity. Conclusion: It is concluded that fruit juice and juiceless fruit pulp extract have shown broad antimicrobial activity while root extract was very effective against some tested microorganisms.
Chapter
Antioxidative Activity Inhibitory Formation of Carcinogen Antimicrobiology References
Article
Modern understanding of nosocomial infections pre-dates the infancy of microbiology as a discipline. The entire concept of infection control is grounded in the work of Ignaz Semmelweis, who in 1840 demonstrated the importance of hand hygiene in controlling infection transmission in hospitals. In the Vienna General Hospital, his investigations led him to conclude that medical students were carrying cadaveric material from the dissection classrooms on their hands and that it was this material that led to the deadly puerperal infections. After considerable struggle with the Viennese medical establishment, he insisted on a strict protocol of hand washing after dissection and before moving to the delivery ward. The effect was a dramatic reduction in the mortality rate. Despite such dramatic results, infection control efforts remained neglected for almost a century. In 1976, the Joint Commission on Accreditation of Healthcare Organizations (JCAHO) published accreditation standards for infection control, creating the impetus and need for hospitals to provide essential support for infection control programs. In 1985, the Centers for Disease Control published a study report on the Efficacy of Nosocomial Infection Control, in which the role of 4 key infection control components (hospital epidemiologist, clinical microbiologist for every 250 beds, active surveillance mechanisms and ongoing control efforts) was emphasized, and following implementation of these measures, nosocomial infection rates were reduced by one-third. Insufficient handwashing by HCWs contributes more to the transmission of enteric pathogens than to the transmission of bloodborne or airborne pathogens. PureHands is an alcohol based polyherbal hand sanitizer and it contains the extracts of Coriandrum sativum, Citrus limon, Azadirachta indica, Vetiveria zizanioides, Coleus vettiveroides in 60% w/w ethyl alcohol. This study was planned to evaluate the efficacy and safety of PureHands in hand hygiene for HCWs. Aim of the study The aim of the study was to evaluate the antimicrobial efficacy and safety (short- and long- term) of PureHands as a hand sanitizer for HCWs in hospital settings.
Article
Full-text available
Background Citrus limon (lemon) belongs to the Rutaceae family and has great therapeutic applications. The chemical ingredients of C. limon have been used in the formulation of several ethnic herbal medicines. The application of antibiotics has shown the development of drug resistance in antibacterial drugs. Due to the drug-resistant nature of microorganisms, there is an urgent need to develop a novel drug active against wildtype and MDR resistant strains of pathogens. Aim The present study is an endeavor to characterize the juice of C. limon towards its total antioxidants potential activity (FRAP), DPPH and antibacterial efficacy. Methods and Materials The antimicrobial activity was evaluated using different bacterial species such as Salmonella typhi, Neisseria gonorrhoeae, Citrobacter species, Shigella flexneri and Staphylococcus epidermidis . Results The results of the present study indicated the antibacterial potential of C. limon fruit juice. Among the tested bacterial species, Shigella flexneri displayed maximum inhibition followed by the other microbes such as Staphylococcus epidermidis, Citrobacter species and Salmonella typhi. Conclusion These findings may be utilized in the development of cost effective, safe and efficient novel drugs active against several pathogenic multi drug-resistant microorganisms.
Article
Full-text available
Nosocomial infections lead to prolonged hospital stays, substantial morbidity and mortality. The hands of HCWs are the primary mode of transmission of multidrug-resistant pathogens and proper hand hygiene is the single most important, simplest and least expensive means of preventing nosocomial infections.
Article
The convenient exploitation of biodegradable and biocompatible PCL/PVA polymers in the field of tissue engineering is limited by their inferior mechanical, thermal and barrier properties. The present study thereby aspires towards supplementing their mechanical properties by exploiting the merits of nanofiber reinforcement and state of the art electrospinning processes. These processes generate nanofibers that can be employed as reinforcing fillers in the synthesis of biocomposites possessing high strength and toughness towards tissue engineering applications. We have demonstrated a green, inexpensive, low energy consuming and one-step technique of steam explosion with lemon juice using an in-house conceptualized autoclave for the disintegration of cellulose micro/nanofibrils from lignocellulosic material. An enhancement in the crystallinity of the native cellulose from 43 to 63% was confirmed by XRD characterization using a peak deconvolution method, and FTIR spectra validated the grafting of the carboxylic groups in citric acid with cellulose fibrils providing the surface modification and superior interaction with a hydrophobic polymer matrix. Thereafter, PCL/PVA polymers were nanoengineered by electrospinning along with the steam explosion generated cellulose micro/nanofibrils to yield PCL/PVA nanoencapsulated cellulose nanofibrils of diameter 40–70 nm, owing to the diffusion of the polymeric material into the porous network of the cellulose fibrils. The resulting fibrils with enhanced surface area, reduced surface roughness and reduced pore size have also displayed antimicrobial properties against Staphylococcus aureus and Escherichia coli bacterial strains, and thus can be used as reinforcing nanoadditives in known biocompatible polymers to give rise to novel biocomposites with enhanced mechanical properties.
Article
Despite the widespread belief that citrus fruit extracts (CFEs) are microbiologically safe due to their acidity, limited bactericidal effect results in low applicability as antibacterial agent and outbreaks occurred by acid-adapted pathogens. Here, we examined the antibacterial effects of CFEs [lime (Citrus medica), lemon (Citrus limon), calamansi (Citrus microcarpa)] combined with essential oil components (EOCs; carvacrol and thymol) against non-acid-adapted/acid-adapted Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes under 22 °C for 5 min. CFEs (<20%) alone or small amounts of EOCs (2.0 mM; 0.032%) alone could not inactivate the target bacteria effectively. However, combined treatments exhibited marked synergy: CFE + EOCs eliminated all the bacteria (>6.9 log CFU/ml). Among the CFEs tested, the highest synergism was shown by calamansi, an exotic citrus fruit previously unrecognized as an antibacterial agent. Although acid-adaptation improved bacterial survival, calamansi (<20%) + EOCs (<0.032%) completely inactivated even the most resistant pathogen (E. coli O157:H7). Validation test also showed that all tested commercial juice products also eliminated acid-adapted pathogens when used with EOCs. Physicochemical analysis of tested CFEs (pH measurement and HPLC analysis of components) revealed that low pH and flavanone (hesperidin) did not contribute to the synergistic bactericidal effects. Rather, the high citric acid content is likely to contribute to the strong synergistic effect with EOCs by damaging susceptible bacterial membranes. Sensory scores for CFEs were not altered by addition of EOCs at concentrations up to 1.5 mM. This study provides new insight into the utility of CFEs with EOCs to improve not only the microbiological safety of food products containing CFEs but also their applicability as natural antibacterial complex.
Article
Full-text available
Objective: The aim of this study was to determine the effect of lime juice on the fetal parameters of Sprague-Dawley rats Materials and Methods: Forty adult female Sprague-Dawley (SD) rats were used. They were randomly divided into 2 groups (I and II) of 10 rats each. The estrous cycles of the rats were studied for the first 16 days to establish cyclicity. The rats were mated with male SD rats of proven fertility on the estrous day (heat period) of estrous cycle. Rats in group I received 1ml of undiluted lime juice while rats in group II received distilled water by gastric gavage. The rats were sacrificed on the 20 th day of gestation using chloroform anesthesia and fetal parameters were evaluated. Results: There was a reduction in the number of fetus of treated pregnant rats when compared to the control which has between eight to eleven litters. There was a significant reduction in the crown-rump length, weight and umbilical cord length of the fetus when compared with the control which was normal. Conclusion: Lime juice showed abortificient effect but no obvious teratogenic effect was observed.
Article
Inactivation of Escherichia coli O157:H7 was evaluated on inoculated apple slices without pretreatment or pretreated by immersing in water or acid solutions commonly used to help retain apple color during dehydration, then stored at ambient temperature or dried for 6 h. Half-ring slices (0.6 cm thick) of peeled and cored Gala apples were inoculated by immersion for 30 min in a three-strain composite inoculum of E. coli O157:H7 (7.8-8.0 CFU/g). Inoculated slices received (1) no pre-drying treatment (control); or a 10-min immersion in solutions of (2) sterile water, (3) 2.8% ascorbic acid, (4) 1.7% citric acid, (5) 50% commercial lemon juice, or (6) 50% commercial lemon juice with preservatives. Drained slices were placed in sterile plastic bags and stored at room temperature (25+/-2 degrees C) for up to 6 h or dehydrated (62.8 degrees C) for up to 6 h. Samples were plated on tryptic soy agar (TSA) and sorbitol MacConkey agar (SMAC) for direct enumeration of surviving bacteria at various time intervals. Immersion in sterile water or acidic solutions caused initial bacterial reductions of 0.9-1.3 log CFU/g on apple slices. Between 0 and 6 h of storage at room temperature, slices dipped in acidic solutions showed minor changes in bacterial populations (-0.2 to +0.6 log CFU/g) compared to a 1.1 log CFU/g increase for slices dipped in sterile water. The no treatment samples (control) showed an increase in bacterial populations of 1.3-1.5 CFU/g over the 6-h holding time. For apple slices dried at 62.8 degrees C, bacterial populations were reduced by 2.5 (SMAC) and 3.1 (TSA) log CFU/g in the control (no pre-drying treatment) samples following 6 h dehydration. The slices immersed in sterile water showed a 5.8 (SMAC) and 5.1 (TSA) reduction after 6 h of dehydration. In contrast, after 6 h of dehydration bacterial populations on the four acid-pretreated products were reduced by 6.7-7.3 log CFU/g. The results showed that acidic treatment alone was not effective in destroying E. coli O157:H7 on apple slices but did inhibit growth of the organism during holding before drying. However, pretreatment of the apple slices with common household acidulants enhanced destruction of E. coli O157:H7 during drying compared to slices dried without treatment.
Article
Aerobic plate counts at 25 C of freshly harvested oysters ranged from 2.3 × 104 to 3.0 × 107 and those of sediment samples from <102 to 3.0 × 106/g. Counts of water samples were nearly always <102/mi. Vibrio, Aeromonas, and Moraxella species predominated in the fresh oysters. Vibrio parahaemolyticus was isolated from 39 of 66 oyster samples and from 9 of 30 sediment and water samples. Isolation was most effective with prior enrichment of samples in trypticase soy broth with 7% NaCl and subsequent plating on thiosulfate citrate bile salts sucrose agar. V. parahaemolyticus was detected in only 1 of 8 refrigerated retail oyster samples. Aerobic plate counts at 25 C of refrigerated retail oysters were not much different from those of similar lots shucked under aseptic conditions in the laboratory (before shucking and washing in the plants). Aeromonas and Moraxella species were predominant in oysters at the retail level.