In Vitro and In Vivo Antibacterial Activity of Punica granatum Peel Ethanol Extract against Salmonella

Plant-Derived Natural Products for the Treatment of Bacterial Infections

Bacterial infections are a significant public health concern, and the emergence of antibiotic-resistant bacteria (ARB) has become a major challenge for modern medicine. The overuse and misuse of antibiotics have contributed to the development of ARB, which has led to the need for alternative therapies. Plant-derived natural products (PNPs) have been extensively studied for their potential as alternative therapies for the treatment of bacterial infections. The diverse chemical compounds found in plants have shown significant antibacterial properties, making them a promising source of novel antibacterial agents. The use of PNPs as antibacterial agents is particularly appealing because they offer a relatively safe and cost-effective approach to the treatment of bacterial infections. This chapter aims to provide an overview of the current state of research on PNPs as antibacterial agents. It will cover the mechanisms of action of the main PNPs against bacterial pathogens and discuss their potential to be used as complementary therapies to combat ARB. This chapter will also highlight the most common screening methodologies to discover new PNPs and the challenges and future prospects in the development of these compounds as antibacterial agents.

Punicalagin, a pomegranate polyphenol sensitizes the activity of antibiotics against three MDR pathogens of the Enterobacteriaceae

BACKGROUND

Multidrug resistance (MDR) in the family Enterobacteriaceae is a perniciously increasing threat to global health security. The discovery of new antimicrobials having the reversing drug resistance potential may contribute to augment and revive the antibiotic arsenal in hand. This study aimed to explore the anti-Enterobacteriaceae capability of bioactive polyphenols from Punica granatum (P. granatum) and their co-action with antibiotics against clinical isolates of Enterobacteriaceae predominantly prevalent in South Asian countries.

METHODS

The Kandhari P. granatum (Pakistani origin) extracts were tested for anti-Enterobacteriaceae activity by agar well diffusion assay against MDR Salmonella enterica serovar Typhi, serovar Typhimurium and Escherichia coli. Predominant compounds of active extract were determined by mass spectrometry and screened for bioactivity by agar well diffusion and minimum inhibitory concentration (MIC) assay. The active punicalagin was further evaluated at sub-inhibitory concentrations (SICs) for coactivity with nine conventional antimicrobials using a disc diffusion assay followed by time-kill experiments that proceeded with SICs of punicalagin and antimicrobials.

RESULTS

Among all P. granatum crude extracts, pomegranate peel methanol extract showed the largest inhibition zones of 25, 22 and 19 mm, and the MICs as 3.9, 7.8 and 7.8 mg/mL for S. typhi, S. typhimurium and E. coli, respectively. Punicalagin and ellagic acid were determined as predominant compounds by mass spectrometry. In plate assay, punicalagin (10 mg/mL) was active with hazy inhibition zones of 17, 14, and 13 mm against S. typhi, S. typhimurium and E. coli, respectively. However, in broth dilution assay punicalagin showed no MIC up to 10 mg/mL. The SICs 30 μg, 100 μg, and 500 μg of punicalagin combined with antimicrobials i.e., aminoglycoside, β-lactam, and fluoroquinolone act in synergy against MDR strains with % increase in inhibition zone values varying from 3.4 ± 2.7% to 73.8 ± 8.4%. In time-kill curves, a significant decrease in cell density was observed with the SICs of antimicrobials/punicalagin (0.03-60 μg/mL/30, 100, 500 μg/mL of punicalagin) combinations.

CONCLUSIONS

The P. granatum peel methanol extract exhibited antimicrobial activity against MDR Enterobacteriaceae pathogens. Punicalagin, the bacteriostatic flavonoid act as a concentration-dependent sensitizing agent for antimicrobials against Enterobacteriaceae. Our findings for the therapeutic punicalagin-antimicrobial combination prompt further evaluation of punicalagin as a potent activator for drugs, which otherwise remain less or inactive against MDR strains.

Development and Evaluation of an Eco-Friendly Hand Sanitizer Formulation Valorized from Fruit Peels

Hand sanitizer usage has proven to be a common and practical method for reducing the spread of infectious diseases which can be caused by many harmful pathogens. There is a need for alcohol-free hand sanitizers because most hand sanitizers on the market are alcohol-based, and regular use of them can damage the skin and can be hazardous. India is the world's largest producer of fruits and one of the major problems after fruit consumption is their peels, causing waste management problems and contributing to the formation of greenhouse gases leading to air pollution and adding to the problem of climate change. Valorization of such wastes into other value-added products and their incorporation into formulations of eco-friendly alcohol-free hand sanitizers would solve these issues, save the environment, benefit the society, and help in achieving the sustainable development goals. Thus, this research focuses on formulating an effective natural alcohol-free hand sanitizer that harnesses the antimicrobial properties of the various types of bioactive components found in fruit peels of pomegranate, sweet lime, and lemon. The peel extracts and the formulated sanitizer proved considerable antimicrobial activity against the pathogenic Escherichia coli and hand microflora. Molecular docking was also applied to examine ligand-protein interaction patterns and predict binding conformers and affinity of the sanitizer phytocompounds towards target proteins in COVID-19, influenza, and pneumonia viruses. The binding affinities and the protein-ligand interactions virtual studies revealed that the sanitizer phytocompounds bind with the amino acids in the target proteins' active sites via hydrogen bonding interactions. As a result, it is possible to formulate a natural, alcohol-free hand sanitizer from fruit peels that is effective against pathogenic germs and viruses using the basic structure of these potential findings.

Therapeutic Potential of Punica granatum and Isolated Compounds: Evidence-Based Advances to Treat Bacterial Infections

Punica granatum Linn has been known for its nutritional and medicinal value since ancient times and is used in the treatment of various pathologies owing to its antibacterial properties. This review reports the results of the most recent studies on the antibacterial effects of P. granatum and its isolated compounds on bacteria of clinical interest. A search in the PubMed, Scopus, Science Direct, and Science Citation Index Expanded (Web of Science) databases was performed, which included articles that evaluated the antibacterial activity of P. granatum extracts and excluded articles that analyzed other microorganisms or nonpathogenic bacteria, as well as theses, dissertations, duplicate articles, and those not fully available. The literature suggests that P. granatum extracts can act on bacteria, such as methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. In addition, fruit peel was the most commonly used pharmacogen and methanol, ethanol, and water were the most common solvents for the extraction of bioactive compounds. The antibacterial potential of the methanolic extract of pomegranate peel could be attributed to the presence of active compounds, such as 5-hydroxymethylfurfural, punicic acid, gallic acid, and punicalagin. Thus, there is evidence that these plant extracts, having high polyphenol content, can disrupt the bacterial plasma membrane and inhibit the action of proteins related to antimicrobial resistance. P. granatum shows antibacterial activity against Gram-positive and Gram-negative bacteria, with great potential against multidrug-resistant strains. Further research is needed to clarify the mechanism of action related to this biological activity and investigate the isolated substances that may be responsible for the antibacterial effects.

Investigation of Pomegranate (Punica granatum L.) Flowers' Antioxidant Properties and Antibacterial Activities against Different Staphylococcus Species Associated with Bovine Mastitis

Mastitis is one of the most considerable and costly diseases for dairy herds, and Staphylococcus spp. is known to be the main causative agent. Although antibiotics are widely used in the treatment of mastitis, this can cause both antibiotic residues in milk and the risk of antibiotic resistance occurrence in bacteria. Thus, in recent years, researchers have focused on alternative treatments for this disease and plants extracts are investigated for this purpose. Pomegranate is widely used as a dye, ornament, and medicinal plants in the industry, and the species has a particularly high economic value in Turkey. This study aims to investigate in vitro the antioxidant and antibacterial properties of the pomegranate flower's extracts against different Staphylococcus species associated with bovine mastitis. To this aim, pomegranate flowers were collected from different regions in Turkey and extracts were prepared with three different solvents (methanol, ethanol, and water). The retention factor values of the ethanol extract were determined by thin-layer chromatography. The antibacterial activity tests were carried out via the disk diffusion method. In addition, the extracts were tested against the stable DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radicals for antioxidant activity. Four retention factors (0.79, 0.67, 0.58, and 0.33 points) were found for the ethanol extract. The methanol extract showed the highest inhibition zones against coagulase-negative Staphylococcus-37 (CNS-37) and S. aureus-18. The lowest MIC was 6500 μg/mL. The highest antioxidant activity was observed in methanol extracts. As a result, the extracts of pomegranate flowers showed a high antioxidant and antibacterial potential against the examined mastitis pathogens.

Natural Antioxidant, Antibacterial, and Antiproliferative Activities of Ethanolic Extracts from Punica granatum L. Tree Barks Mediated by Extracellular Signal-Regulated Kinase

The nonedible parts of the pomegranate plant, such as tree barks and fruit peels, have pharmacological properties that are useful in traditional medicine. To increase their value, this study aimed to compare the antioxidative and antibacterial effects of ethanolic extracts from pomegranate barks (PBE) and peels (PPE). The antiproliferative effects on HeLa and HepG2 cells through the extracellular signal-regulated kinase pathway were also evaluated. The results indicated that the total amounts of phenolics and flavonoids of PBE and PPE were 574.64 and 242.60 mg equivalent gallic acid/g sample and 52.98 and 23.08 mg equivalent quercetin/g sample, respectively. Gas chromatography−mass spectrometry revealed that 5-hdroxymethylfurfural was the major component of both PBE (23.76%) and PPE (33.19%). The 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical scavenging capacities of PBE and PPE, in terms of the IC50 value, were 4.1 and 9.6 µg/mL, respectively. PBE had a greater potent antibacterial effect against Escherichia coli, Staphylococcus aureus, Salmonella Enteritidis, and S. Typhimurium. PBE and PPE (1000 µg/mL) had exhibited no cytotoxic effects on LLC-MK2. PBE and PPE (250 and 1000 µg/mL, respectively) treatments were safe for BHK-21. Both extracts significantly inhibited HepG2 and HeLa cell proliferations at 10 and 50 µg/mL, respectively (p < 0.001). The results indicated that PBE and PPE have remarkable efficiencies as free radical scavengers and antibacterial agents, with PBE exhibiting greater efficiency. The inhibitory effects on HepG2 might be through the modulation of the ERK1/2 expression. PBE and PPE have the potential for use as optional supplementary antioxidative, antibacterial, and anticancer agents.

Green synthesis of Zirconium nanoparticles using Punica granatum (pomegranate) peel extract and their antimicrobial and antioxidant potency

The biosynthesis of metal oxide nanoparticles provides an excellent alternative to the chemical synthesis approach. The aim of the current study was a green and eco-friendly synthesis of zirconium nanoparticles (ZrNPs) from fruit peels of Punica granatum (Pomegranate). The synthesis of ZrNPs was confirmed using a UV-visible spectrophotometer. The functional groups present on surface of ZrNPs were analyzed using FTIR. The average size of obtained ZrNPs was analyzed using SEM and DLS and it was around 20-60 nm. The antimicrobial activity of obtained ZrNPs was tested against Gram-positive strains (Bacillus subtilis and Staphylococcus aureus), Gram-negative strains (Escherichia coli and Klebsiella pneumoniae) and Fungi (Aspergillus niger) by agar well diffusion method. ZrNPs showed maximum zone of inhibition against S. aureus (19 mm) and A. niger (18 mm) at the maximum concentration of 200 μg/mL. The antioxidant scavenging activity of obtained ZrNPs was analyzed using the following methods: DPPH radical scavenging activity, Hydroxyl radical scavenging activity, Ferric reducing antioxidant power and hydrogen peroxide radical scavenging activity. This the first and foremost study on ZrNPs synthesized using P. granatum fruit peel extract reporting their efficacy as antimicrobial agents against Bacteria and Fungi. Considering the tolerance of zirconium towards human body, it can also be used as antimicrobial coating material on human implants.

Plant Extract-Based Synthesis of Metallic Nanomaterials, Their Applications, and Safety Concerns

Nanotechnology has attracted the attention of researchers from different scientific fields because of the escalated properties of nanomaterials compared with the properties of macromolecules. Nanomaterials can be prepared through different approaches involving physical and chemical methods. The development of nanomaterials through plant-based green chemistry approaches is more advantageous than other methods from the perspectives of environmental safety, animal, and human health. The biomolecules and metabolites of plants act as reducing and capping agents for the synthesis of metallic green nanomaterials. Plant-based synthesis is a preferred approach as it is not only cost-effective, easy, safe, clean, and eco-friendly but also provides pure nanomaterials in high yield. Since nanomaterials have antimicrobial and antioxidant potential, green nanomaterials synthesized from plants can be used for a variety of biomedical and environmental remediation applications. Past studies have focused mainly on the overall biogenic synthesis of individual or combinations of metallic nanomaterials and their oxides from different biological sources, including microorganisms and biomolecules. Moreover, from the viewpoint of biomedical applications, the literature is mainly focusing on synthetic nanomaterials. Herein, we discuss the extraction of green molecules and recent developments in the synthesis of different plant-based metallic nanomaterials, including silver, gold, platinum, palladium, copper, zinc, iron, and carbon. Apart from the biomedical applications of metallic nanomaterials, including antimicrobial, anticancer, diagnostic, drug delivery, tissue engineering, and regenerative medicine applications, their environmental remediation potential is also discussed. Furthermore, safety concerns and safety regulations pertaining to green nanomaterials are also discussed. This article is protected by copyright. All rights reserved.

Controlling Growth of Multidrug-Resistant Staphylococci Isolated from Sports Mats: A Report from the Golestan Province, Iran

Background: Gyms are among the places where various human infections can spread. One of the most important strategies to prevent infection spread among athletes is the use of strong and effective disinfectants. Objectives: The aim of this study was to evaluate and compare the antiseptic properties of chlorhexidine gluconate and pomegranate peel extract on staphylococcal isolates from sports mats. Methods: This descriptive-analytical study was performed on 22 Staphylococcus aureus, and Staphylococcus epidermidis isolates from a total of 105 sports mat samples. After identification of multi-drug resistant (MDR) staphylococcal isolates, the antimicrobial effect of chlorhexidine gluconate 20% and pomegranate peel extract was evaluated by broth microdilution according to the instructions of the Clinical and Laboratory Standards Institute. Results: Overall, 14 (66.7%) S. aureus and 8 (28.6%) S. epidermidis isolates resistant to azithromycin, linezolid, ciprofloxacin, vancomycin, and aztreonam were reported as MDR strains. The minimum inhibitory concentration (MIC) of chlorhexidine gluconate, which inhibited the growth of 90% of MDR S. aureus isolates was 250 μg/mL, which was 4-fold lower than the MIC of pomegranate peel extract (MIC90 ≥ 500μg/mL) and 2-fold lower against MDR S. epidermidis isolates (MIC90 ≤ 125 μg/mL). The MIC of chlorhexidine gluconate and pomegranate peel extract against S. aureus isolates differed significantly (P = 0.037). Conclusions: Compared to pomegranate peel extract, chlorhexidine gluconate has a higher antibacterial effect on MDR staphylococcal isolates from sports mats. Further research is required to verify the efficacy of this biocide for disinfection of gyms and sports clubs.

The antimicrobial effect behind Cannabis sativa

The development of multidrug-resistant bacteria has revealed the need for new antimicrobial compounds. Cannabis sativa preparations have a long history of medical applications, including the treatment of infectious diseases. This review collects the information about the activity of C. sativa extracts and its main components (cannabinoids and terpenes) against pathogenic bacteria and fungus, to assess its potential using as antimicrobial agents.

Persian medicine recommendations for the prevention of pandemics related to the respiratory system: a narrative literature review

BACKGROUND

Pandemics of infectious diseases have long been regarded as societal challenges. This study aimed to summarize the theories of Persian medicine for controlling respiratory disease-related pandemics and to compare these theories with the findings of modern medicine.

METHODS

We searched the classic medical reference books of the 9th to 19th centuries for the terms 'polluted air' and 'pandemic', and we searched 4 databases (PubMed, Google Scholar, Science Direct, and Scopus) with the keywords 'COVID-19', 'pandemic', 'history', and 'prevention programs'. The results were collected and subjected to content analysis.

RESULTS

From the point of view of traditional Iranian physicians, disease prevention is primarily possible by avoiding pathogenic factors. As a secondary solution, reducing one's susceptibility to the disease is crucial; this can be achieved through cleansing the body and strengthening the mood, reducing food intake, decreasing the internal humidity, disinfecting the house with herbal fumigation, and making use of pleasant aromas. Some of these recommendations are reaffirmed by modern research.

CONCLUSION

Persian medicine techniques may be preventive during respiratory, influenza-like disease pandemics. However, rigorous studies are needed to confirm this hypothesis.

Challenges to antimicrobial susceptibility testing of plant-derived polyphenolic compounds

As multidrug resistance gains momentum, the last two decades have seen an ever-growing interest in the antimicrobial properties of plant extracts and plant-derived compounds. Most of the focus is on polyphenols – a large and diverse group of phytochemicals with strong antibacterial activity. Testing methods provide reliable results as long as they follow standard procedures. However, methods and procedures used in antimicrobial susceptibility testing (AST) are often too diverse to allow comparison of results. The lack of uniformity and comparability is much owed to the absence of guidelines. The focus of this review is to give a critical overview of different methods used in the assessment of polyphenols antimicrobial efficacy and to highlight the importance of their standardisation.

Variability in Phytochemical Contents and Biological Potential of Pomegranate (Punica granatum) Peel Extracts: Toward a New Opportunity for Minced Beef Meat Preservation

Extraction of Tunisian pomegranate peels was employed with different solvents such as ethyl acetate, acetonitrile, and water. Total phenolic and flavonoids contents, antioxidant activity, and antibacterial capacity against five foodborne pathogenic bacteria were evaluated. The highest values of polyphenols (351 mg gallic acid equivalent/g), flavonoids (104 mg quercetin/g), and DPPH and ABTS inhibition were recorded in the ethyl acetate extract followed by the aqueous extract. The latter present the maximum antibacterial potential against S. enterica, P. aeruginosa, and E. coli. The potential use of the lyophilized aqueous extract (AE), used for safety reason and being rich in phenolic, as biopreservative in minced beef meat was described. AE was incorporated at 0.1, 0.5, and 1% and compared with 0.1% butylated hydroxytoluene (BHT). During 21 days at 4°C, AE at 1% could appreciably retard the microflora proliferation (p<0.05), the accumulation of MetMb and the carbonyl group (p<0.05), slowing down the loss of sulphydryl proteins (p<0.05), and led to a decrease (p<0.05) in primary (peroxide value and conjugated dienes) and secondary lipid oxidation (TBARS) in treated meat. By the 14th day, AE-treated minced meat obtained higher sensory scores than untreated and BHT samples. Based on these results, lipid and protein oxidation changes and sensorial attributes were useful in discriminating meat samples by overall acceptability prediction. Generally, AE at 1% presented the potent preservative effect that could be utilized as an application on meat-substituting synthetic antioxidant.

Polyphenols profile of pomegranate leaves and their role in green synthesis of silver nanoparticles

The current study reports on polyphenols profile of pomegranate leaves (PL) Punica granatum grown in Egypt and exhibiting their role in development of an eco-friendly method of green synthesis of silver nanoparticles (AgNPs). PL aqueous alcohol extract was fractionated, the major phenolic compound was isolated from the polyphenols rich fraction (ethyl acetate fraction) and identified by conventional and spectroscopic methods of analysis as ellagic acid. Furthermore, the fraction was standardized and analysed using UPLC-PDA-UV and LC–MS-MS techniques revealing tentative identification of 23 polyphenolic compounds, quantifying ellagic acid as 43.14 ± 0.57 μg/mg of the fraction. AgNPs were successfully synthesized with the aid of polyphenols rich fraction. This is the first report revealing the systematic optimization of the green synthesis process using various independent variables. AgNPs were characterized by adopting UV–Vis spectroscopy, FTIR, XRD, and SEM, which revealed strong SPR band within average of λ _max 425 nm and polygonal shaped nanoparticles of 26.22 nm size, respectively. The antimicrobial efficacies of AgNPs and polyphenols rich fraction were tested against Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, and Sarcina lutea), Gram-negative bacteria (Salmonella paratyphi, Escherichia coli, and Pseudomonas aeruginosa) and fungi (Candida albicans). AgNPs showed a concentration-dependent activity against all the tested microorganisms.

Evaluation of in-vivo anti-Salmonella activity of Uvaria chamae, Lantana camara and Phyllantus amarus used in Benin, West Africa

BACKGROUND

Uvaria chamae (Annonaceae), Phyllantus amarus (Phyllantaceae) and Lantana camara (Verbenaceae) are empirically alleged to be used as Beninese medicinal plants in the treatment of salmonellosis. This study aimed to produce scientific data on in vitro and in vivo efficacy of Uvaria chamae, Lantana camara and Phyllantus amarus on multiresistant Salmonella spp isolated in Benin.

RESULTS

After performing in vitro tests on aqueous and ethanolic extracts of these plants, only the aqueous extract of Uvaria chamae (leaves) showed the best anti-Salmonella's activity and was used for this in vivo experiment. The induction of salmonellosis revealed 9 × 108 CFU/ml was the optimal concentration triggering and maintaining symptoms in chicks. This infective concentration was used for in vivo assessment. Twenty-four hours post inoculation, the symptoms of salmonellosis (wet cloaca, diarrhea stools and somnolence) were observed in infected groups. After 7 days of treatment, the reduction of bacterial load at 100 mg/L, 200 mg/L, 400 mg/L of the extract was respectively 85%, 52.38% and 98% for Uvaria chamae, Phyllantus amarus and Lantana camara in the chick's groups infected with Salmonella Typhimurium ATCC 14028. On the other hand, colistin completely cancelled the bacterial load (reduction rate of 100%). With the groups infected with Salmonella spp (virulent strain), the reduction rate of bacterial load at 100 mg/L, 200 mg/L, 400 mg/L of extract was 0%, 98.66%, and 99.33%. The extracts at 200 and 400 mg/L were more active than colistin, which reduced the bacterial load by 33.33%. The toxicity tests did not show any negative effect of Colistin and the Uvaria chamae's extract on the biochemical and hematological parameters of the chicks.

CONCLUSION

The aqueous extract of Uvaria chamae is active in vitro and in vivo on multiresistant strains of Salmonella enterica. This plant is a good candidate for the development of an improved traditional medicine for the management of salmonellosis.

Multiresponse Optimization of Pomegranate Peel Extraction by Statistical versus Artificial Intelligence: Predictive Approach for Foodborne Bacterial Pathogen Inactivation

Pomegranate (Punica granatum L.) peel is a potential source of polyphenols known for their activity against foodborne pathogen bacteria. In this study, the effects of pomegranate peel extraction time (10–60 min), agitation speed (120–180 rpm), and solvent/solid ratio (10–30) on phytochemical content and antibacterial activity were determined. Response surface methodology (RSM) and artificial neural network (ANN) methods were used, respectively, for multiresponse optimization and predictive modelling. Compared with the original conditions, the total phenolic content (TPC), the total flavonoid content (TFC), and the total anthocyanin content (TAC) increased by 56.22, 63.47, and 64.6%, respectively. Defined by minimal inhibitory concentration (MIC), the maximum of antibacterial activity was higher than that from preoptimized conditions. With an extraction time of 11 min, an agitation speed 125 rpm, and a solvent/solid ratio of 12, anti-S. aureus activity remarkably decreased from 1.56 to 0.171 mg/mL. Model comparisons through the coefficient of determination (R²) and mean square error (MSE) showed that ANN models were better than the RSM model in predicting the photochemical content and antibacterial activity. To explore the mode of action of the pomegranate peel extract (PPE) at optimal conditions against S. aureus and S. enterica, Chapman and Xylose Lysine Deoxycholate broth media were artificially contaminated at 10⁴ CFU/mL. By using statistical approach, linear (ANOVA), and general (ANCOVA) models, PPE was demonstrated to control the two dominant foodborne pathogens by suppressing bacterial growth.

Anti-infective potential of hydroalcoholic extract of Punica granatum peel against gram-negative bacterial pathogens

Background: Punica granatum extracts have been prescribed in traditional medicine for management of a variety of disease conditions including microbial infections. Generation of scientific evidence for validation of P. granatum peel extract's anti-pathogenic efficacy is required. Methods: Hydroalcoholic extract of P. granatum peel (PGPE), prepared by microwave assisted extraction method was evaluated for its quorum-modulatory potential against two different human-pathogenic bacteria viz. Chromobacterium violaceum and Pseudomonas aeruginosa. Results: This extract was able to modulate in vitro production of quorum sensing-regulated pigments in both these test bacteria at ≥5 μg/ml. Virulence traits of P. aeruginosa like haemolytic activity, and biofilm formation were negatively affected by the test extract, and it also made P. aeruginosa more susceptible to lysis by human serum. Antibiotic susceptibility of both test bacteria was modulated owing to pre-treatment with PGPE. Exposure of these test pathogens to PGPE (≥0.5 μg/ml) effectively reduced their virulence towards the nematode Caenorhabditis elegans. Repeated subculturing of P. aeruginosa on PGPE-supplemented growth medium did not induce resistance to PGPE in this notorious pathogen, and this extract was also found to exert a post-extract effect on P. aeruginosa. Individual constituent phytocompounds of PGPE were found to be less efficacious than the whole extract. PGPE seemed to interfere with the signal-response machinery of P. aeruginosa and C. violaceum. PGPE also exhibited notable prebiotic potential by promoting growth of probiotic strains- Bifidobacterium bifidum and Lactobacillus plantarum at ≤50 μg/ml. Conclusions: This study indicates PGPE to be an effective antipathogenic and prebiotic preparation, and validates its therapeutic use mentioned in traditional medicine. This study also emphasizes the need for testing any bioactive extract at broadest possible concentration range, particularly in vivo, so that an accurate picture of dose-response relationship can emerge.

Anti-infective potential of hydroalcoholic extract of Punica granatum peel against gram-negative bacterial pathogens

Background:Punica granatum extracts have been prescribed in traditional medicine for management of a variety of disease conditions including microbial infections. Generation of scientific evidence for validation of P. granatum peel extract's anti-pathogenic efficacy is required. Methods: Hydroalcoholic extract of P. granatum peel (PGPE), prepared by microwave assisted extraction method was evaluated for its quorum-modulatory potential against two different human-pathogenic bacteria viz. Chromobacterium violaceum and Pseudomonas aeruginosa. Results: This extract was able to modulate in vitro production of quorum sensing-regulated pigments in both these test bacteria at ≥5 μg/ml. Virulence traits of P. aeruginosa like haemolytic activity, and biofilm formation were negatively affected by the test extract, and it also made P. aeruginosa more susceptible to lysis by human serum. Antibiotic susceptibility of both test bacteria was modulated owing to pre-treatment with PGPE. Exposure of these test pathogens to PGPE (≥0.5 μg/ml) effectively reduced their virulence towards the nematode Caenorhabditis elegans. Repeated subculturing of P. aeruginosa on PGPE-supplemented growth medium did not induce resistance to PGPE in this notorious pathogen, and this extract was also found to exert a post-extract effect on P. aeruginosa. Individual constituent phytocompounds of PGPE were found to be less efficacious than the whole extract. PGPE seemed to interfere with the signal-response machinery of P. aeruginosa and C. violaceum. PGPE also exhibited notable prebiotic potential by promoting growth of probiotic strains- Bifidobacterium bifidum and Lactobacillus plantarum at ≤50 μg/ml. Conclusions: This study indicates PGPE to be an effective antipathogenic and prebiotic preparation, and validates its therapeutic use mentioned in traditional medicine. This study also emphasizes the need for testing any bioactive extract at broadest possible concentration range, particularly in vivo, so that an accurate picture of dose-response relationship can emerge.

Antimicrobial and Cytotoxicity Effects of Synthesized Silver Nanoparticles from Punica granatum Peel Extract

To address the growing challenges from drug-resistant microbes and tumor incidence, approaches are being undertaken to phytosynthesize metal nanoparticles, particularly silver nanoparticles, to get remedial measure. In this study, an attempt has been made to utilize a major biowaste product, pomegranate fruit peel (Punica granatum), to synthesize silver nanoparticles. The silver nanoparticles (AgNPs) were synthesized using the aqueous extract of pomegranate peel. The formation of synthesized AgNPs was confirmed through UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) as well as through the change of the colorless aqueous solution to a dark brown solution. Using UV-Vis spectroscopy, the dark brown solution showed a Plasmon resonance band peak at 378 nm in UV-Vis spectroscopy after reacting for 24, 48, and 72 h. The XRD report revealed that the AgNPs had a cubic structure. The TEM and SEM report showed the nanoparticles were equally distributed in the solution, with a spherical shape and size ranging from 20 to 40 nm and with an average particle size of 26.95 nm. EDX imaging also confirmed the presence of AgNPs. The synthesized AgNPs were found to exhibit good antimicrobial effects on Gram-negative and Gram-positive bacteria, particularly the pathogens Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27584), Proteus vulgaris (ATCC 8427), Salmonella typhi (ATCC 14028), Staphylococcus aureus (ATCC 29213), Staphylococcus epidermidis (MTCC 3615), and Klebsiella pneumonia. The cytotoxic effects of AgNPs were also tested against a colon cancer cell line (RKO: ATCC® CRL-2577™), and it was observed that the viabilities were 56% and 61% on days 3 and 5, respectively, with exposure to 12.5 μg of AgNPs. This simple, economic, and eco-friendly method suggests that the AgNPs biosynthesized using pomegranate peel extract may be a novel, potent solution for the development of a drug for colon cancer that also has antibacterial activity.

Gallic Acid: Review of the Methods of Determination and Quantification

Gallic acid (3,4,5 trihydroxybenzoic acid) is a secondary metabolite present in most plants. This metabolite is known to exhibit a range of bioactivities including antioxidant, antimicrobial, anti-inflammatory, and anticancer. There are various methods to analyze gallic acid including spectrometry, chromatography, and capillary electrophoresis, among others. They have been developed to identify and quantify this active ingredient in most biological matrices. The aim of this article is to review the available information on analytical methods for gallic acid, as well as presenting the advantages and limitations of each technique.

Studies on the therapeutic effect of propolis along with standard antibacterial drug in Salmonella enterica serovar Typhimurium infected BALB/c mice

BACKGROUND

Antibiotic resistance is an emerging public health problem. Centers for Disease Control and Prevention (CDC) has described antibiotic resistance as one of the world's most pressing health problems in 21^st century. WHO rated antibiotic resistance as "one of the three greatest threats to human health". One important strategy employed to overcome this resistance is the use of combination of drugs. Many plants, natural extracts have been shown to exhibit synergistic response with standard drugs against microorganisms. The present study focused on the antibacterial potential of propolis in combination with the standard antibiotic Cefixime against the typhoid causing bacteria i.e. Salmonella.

METHODS

Ethanolic extract of propolis was taken for the present work. For the experiment BALB/c mice were taken as animal model and divided into ten groups. Along with normal and infected control groups, four different combinations of cefixime and propolis were used. Biochemical, hematological and histopathological indices were studied by following the standard protocols.

RESULTS

In BALB/c mice, Salmonella causes severe biochemical, hematological and histopathological alterations by 5^th day of infection. Ethanolic extract of propolis at a dose of 300 mg/kg body weight of mice when used alone to treat Salmonella infection in mice gave significant results by 30^th day of treatment. Similarly, when cefixime (4 mg/kg body weight of mice) was used to treat infection in mice, significant results as compared to infected control were observed after 5^th day. But when propolis and cefixime were used together in different concentrations in combination therapy, evident results were observed after 5 days of treatment. The levels of various liver and kidney function enzymes, blood indices and the histopathology of liver, spleen and kidney were restored to near normal after 5 days of treatment and at much lower doses as compared to the effective dose when used alone.

CONCLUSION

The study confirmed that significant results were observed in three combinations of cefixime and propolis as compared to infected controls. Propolis acted synergistically with cefixime and enhanced the efficacy of antibiotic and reduced its effective dose in combined therapy.

Efficacy of Yeast' Vacuoles as Antimicrobial Agents to Escherichia coli Bacteremia in Rat

Yeast vacuoles, lysosomes, are cell organelles that have antimicrobial activity against several bacteria in vitro. Lysosomes have a potential application to the treatment of pathogens such as antibiotics in vivo. Therefore, the in vivo efficacy of lysosomes was examined in a rat infection model against pathogenic Escherichia coli with varying susceptibilities to standard antimicrobial agents. Before in vivo testing, the concentration-dependent safety of lysosomes was confirmed by blood test and histopathology of normal rats. The therapeutic efficacy of lysosomes was examined in terms of the survival of E. coli in infected rat blood. The complete blood count and histopathology results were affected by the lysosomes concentration. In addition, the E. coli growth was inhibited by the initial injection of lysosomes. These results support the use of lysosomes as a bacterial inhibitor of an infected rat model.

Punica granatum L. (Pomegranate) Extract: In Vivo Study of Antimicrobial Activity against Porphyromonas gingivalis in Galleria mellonella Model

Due to the increase of bacterial resistance, medicinal alternatives are being explored. Punica granatum L. is an effective herbal extract with broad spectrum of action and bactericidal, antifungal, anthelmintic potential and being able to modulate the immune response. The aim was to evaluate the antimicrobial activity of pomegranate glycolic extract (PGE) against the periodontal pathogen Porphyromonas gingivalis by using Galleria mellonella as in vivo model. Fifteen larvae were used per group. Injection of high concentration (200, 100, and 25 mg/mL) of PGE showed a toxic effect, leading them to death. A suspension of P. gingivalis (10⁶ cells/mL) was inoculated in the left last proleg and PGE (12.5, 6.25, 3.1, and 2.5 mg/mL) were injected into the right proleg. The larvae were then kept at 37°C under the dark. Injection of PGE at any dose statistically improved larvae survival rates. The data were analysed (log-rank test, Mantel-Cox, P < 0.05) and showed that all concentrations of PGE (12.5, 6.25, 3.1, and 2.5 mg/mL) presented higher larval survival rates, with significant statistical difference in relation to control group (P. gingivalis). In conclusion, the PGE had antimicrobial action against P. gingivalis in vivo model using G. mellonella.

Total phenolic and flavonoid content and antibacterial activity of Punica granatum L. var. pleniflora flowers (Golnar) against bacterial strains causing foodborne diseases

BACKGROUND

Flowers of Punica granatum L. (Punicaceae) var. pleniflora, known as "Golnar" in Iranian traditional medicine have been used for the prevention and treatment of foodborne diseases. In this study, antibacterial activities of ethanol extract of Golnar and its fractions were scientifically evaluated against bacteria causing foodborne diseases including Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Escherichia coli, Shigella dysantriae, and Salmonella typhi. The total phenolic and flavonoid contents of the extract and its fractions were also determined.

METHODS

The antibacterial effect of the ethanol extract and its fractions were primarily evaluated by agar well diffusion and their MIC and MBC were determined by broth macro dilution method. The total phenolic and flavonoid contents of the extract and its fractions were measured based on gallic acid and rutin equivalents (GAE and RE), respectively.

RESULTS

After evaluation of total phenolic and flavonoid content the chloroform fraction showed the lowest phenolic and flavonoid contents (3.8 mg GAE/g and 1.1 mg RE/g respectively) and the methanol fraction showed the highest phenolic and flavonoid contents (18.1 mg GEA/g and 3.3 mg RE/g respectively). The total phenolic and flavonoid content was positively associated with the antibacterial activities of the fractions with chloroform extract exhibiting lowest antibacterial activity against E. coli (MIC 25 mg/ml) and the methanol fraction exhibiting the highest antibacterial effect against S. aureus (MIC 0.19 mg/ml).

CONCLUSION

Golnar extract showed antibacterial activity against both Gram positive and Gram negative bacteria causing food poisoning. Therefore, the extract can be used for prevention or treatment of foodborne diseases or as preservative in the food industry. The methanol fraction with the highest phenolic and flavonoid content showed the highest antibacterial effect. This indicates that the phenolic and flavonoid compounds in the extract can be responsible for the effect.

Antibacterial activity of fresh pomegranate juice against clinical strains of Staphylococcus epidermidis

BACKGROUND

Polyphenols have received a great deal of attention due to their biological functions. Pomegranate (Punica granatum L.) is a polyphenol-rich fruit. In the past decade, studies testing the antimicrobial activity of pomegranates almost exclusively used solvent extracts instead of fresh pomegranate juice (FPJ). The use of FPJ instead of solvent extracts would reduce toxicity issues while increasing patient acceptance. We established a model to test FPJ as a natural antimicrobial agent.

OBJECTIVE

To evaluate the antimicrobial activity of FPJ on clinical isolates of multidrug-resistant Staphylococcus epidermidis strains.

DESIGN

Sixty strains of S. epidermidis isolated from ocular infections were grown in the presence of FPJ, and minimum inhibitory concentration (MIC) was determined by broth and agar dilution methods.

RESULTS

FPJ at 20% had a MIC equal to 100% (MIC100%) on all 60 strains tested. This inhibition of FPJ was confirmed by the growth kinetics of a multidrug-resistant strain exposed to different concentrations of FPJ. Additionally, the antimicrobial activity of FPJ was compared against commercial beverages containing pomegranate: Ocean Spray(®) had a MIC100% at 20%, followed by Del Valle(®) with a MIC15% at 20% concentration only. The beverages Jumex(®) and Sonrisa(®) did not have any antimicrobial activity. FPJ had the highest polyphenol content and antioxidant capacity.

CONCLUSIONS

Overall, FPJ had antimicrobial activity, which might be attributed to its high polyphenol content and antioxidant capacity.

Preparation and characterisation of Punica granatum pericarp aqueous extract loaded chitosan-collagen-starch membrane: role in wound healing process

Engineered scaffolds made from natural biomaterials are crucial elements in tissue engineering strategies. In this study, biological scaffold like chitosan-collagen-starch membrane (CCSM) loaded with the antibacterial agent, Punica granatum pericarp aqueous extract was explored for enhanced regeneration of epithelial tissue during wound healing. Collagen was extracted from Rachycentron canadum fish skin. Membranous scaffold was prepared by mixing collagen, starch and chitosan in a fixed proportion, loaded with aqueous extract of P. granatum and its anti-pseudomonal activity was studied. Morphological characterization by SEM and mechanical property like tensile strength of the membrane were studied. Excision wound of 2 cm(2) size was induced in Guinea pig and the effect of P. granatum extract loaded CCSM in wound healing was studied. The SEM image showed deep pores in the membrane and also possessed good tensile strength. Wound surface area was reduced prominently in the experimental group with P. granatum extract loaded CCSM when compared to the group with unloaded membrane and the one with no membrane. Punica granatum extract loaded CCSM has antipseudomonal property and supported enhanced epithelial cell proliferation without leaving a scar after wound healing. This has significant therapeutic application in membranous scaffold mediated skin repair and regeneration.

Antibacterial efficacy of five medicinal plants against multidrug-resistant enteropathogenic bacteria infecting under-5 hospitalized children

OBJECTIVE

To evaluate in vitro antibacterial effectiveness of five medicinal plants used by an Indian aborigine, against 8 multidrug-resistant (MDR) enteropathogenic bacteria isolated from clinical samples of under-5 hospitalized children.

METHODS

Antibiotic sensitivity patterns of eight clinically isolated strains of enteropathogenic bacteria, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, Salmonella paratyphi, S. typhi, Shigella dysenteriae, S. sonnei and Vibrio cholerae were assessed by disc-diffusion method. Antibacterial activities of 8 solvent-extracts of leaves and bark of five medicinal plants were monitored by the agar-well diffusion method. The microbroth dilution method was used to assess minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). Qualitative phytochemical analyses of active plant extracts were carried out.

RESULTS

Ethanol, ethyl acetate and methanol extracts of Holarrhena antidysenterica leaf tissue were most effective against 8 MDR pathogens in vitro. Similarly, acetone, ethanol and methanol extracts of Terminalia alata leaf tissue; chloroform, ethyl acetate and methanol extracts of Terminalia arjuna leaf tissue and ethyl acetate, ethanol and methanol extracts of Paederia foetida leaf tissue were most effective in inhibiting in vitro growth of the 8 MDR enteropathogens. Ethyl acetate and methanol extracts of H. antidysenterica bark tissue; acetone, ethanol and methanol extracts of T. alata bark tissue and acetone, ethanol and methanol extracts of T. arjuna bark tissue were most effective in controlling enteropathogen growth. The minimum inhibitory concentration and minimum bactericidal concentration values of the 3 most antimicrobial leaf and bark extracts from the five plants were in the range of 1.56 to 50 mg/mL.

CONCLUSION

These 5 plants exhibited in vitro control over a cohort of 8 enteropathogenic bacterial strains isolated from clinical samples.

Bioavailability of dietary polyphenols and gut microbiota metabolism: antimicrobial properties

Polyphenolic compounds are plant nutraceuticals showing a huge structural diversity, including chlorogenic acids, hydrolyzable tannins, and flavonoids (flavonols, flavanones, flavan-3-ols, anthocyanidins, isoflavones, and flavones). Most of them occur as glycosylated derivatives in plants and foods. In order to become bioactive at human body, these polyphenols must undergo diverse intestinal transformations, due to the action of digestive enzymes, but also by the action of microbiota metabolism. After elimination of sugar tailoring (generating the corresponding aglycons) and diverse hydroxyl moieties, as well as further backbone reorganizations, the final absorbed compounds enter the portal vein circulation towards liver (where other enzymatic transformations take place) and from there to other organs, including behind the digestive tract or via blood towards urine excretion. During this transit along diverse tissues and organs, they are able to carry out strong antiviral, antibacterial, and antiparasitic activities. This paper revises and discusses these antimicrobial activities of dietary polyphenols and their relevance for human health, shedding light on the importance of polyphenols structure recognition by specific enzymes produced by intestinal microbial taxa.

Antimicrobial and free radical scavenging activities of five Palestinian medicinal plants

Extracts from five indigenous Palestinian medicinal plants including Rosmarinus officinalis, Pisidium guajava, Punica granatum peel, grape seeds and Teucrium polium were investigated for antimicrobial and free radical scavenging activities against eight microorganisms, using well diffusion method. The microorganisms included six bacterial isolates (i.e. Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginos, Klebsiella pneumonia, Bacillus subtilis and Micrococcus luteus) and two fungal isolates (i.e. Candida albicans and Aspergillus niger). A standard antioxidant assay was performed on the plant extracts to assess their capability in scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH). Of the five tested plant extract, only Rosmarinus offcinalis extract contained significant antimicrobial activity against all eight microbial isolates including Pseudomonas aeruginosa. Extracts from other four plants exhibited a variable antimicrobial activity against all microorganisms, except Pseudomonas aeruginosa. Significant antioxidant activity was detected in all plant extracts. However, extracts from Pisidium guajava leaves contained significantly higher antioxidant activity compared to the other extracts tested. The antimicrobial and scavenging activities detected in this in vitro study in extracts from the five Palestinian medicinal plants suggest that further study is needed to identify active compounds to target diseases caused by a wide-spectrum pathogens.

Pomegranate (Punica granatum) peel is effective in a murine model of experimental Cryptosporidium parvum

Cryptosporidiosis, a major health issue for neonatal calves, is caused by the parasite Cryptosporidium parvum, which is highly resistant to drug treatments. To date, many anti-parasitic drugs have been tested, but only a few have been shown to be partially effective in treating cryptosporidiosis. Previous studies have indicated that pomegranate (Punica granatum) possesses anti-plasmodium, anti-cestode, and anti-nematode activities. Therefore, the aim of this study was to evaluate the effect of P. granatum peel on suckling mice infected with experimental C. parvum. At 4days of age, 72 neonatal albino mice were randomly divided into five groups: G1: healthy controls, G2: infected/untreated controls, G3: uninfected/distilled water-treated, G4: uninfected/P. granatum peel-treated, and G5: infected/P. granatum peel-treated. Mice were experimentally-infected by oral administration of 1×10(3)C. parvum oocysts per animal. On day 7 post-inoculation (pi), treated mice received an aqueous suspension of P. granatum peel orally (3g/kg body weight). The presence of diarrhea, oocyst shedding, and weight gain/loss, and the histopathology of ileal sections were examined. Infected mice treated with the P. granatum peel suspension showed improvement in all parameters examined. Additionally, these mice did not exhibit any clinical symptoms and no deaths occurred. Oocyst shedding was very significantly reduced in the P. granatum-treated mice by day 14 pi (P<.05), and was completely eliminated by day 28 pi. The mean weight gain of the P. granatum-treated mice was significantly higher than that of the infected/untreated controls throughout the study (P<.01). Histopathological analysis of ileal sections further supported the clinical and parasitological findings. The histological architecture of villi from the P. granatum-treated mice on day 14 pi showed visible improvement in comparison with the infected/untreated controls, including renewed brush borders, reduced numbers of C. parvum trophozoites, and reduced lymphatic infiltration. On day 28 pi, tissues of the P. granatum-treated mice were very similar to those of healthy control mice. These results suggest that P. granatum peel is a promising anti-coccidial therapeutic treatment that lacks negative side effects.

A preliminary investigation of the jack-bean urease inhibition by randomly selected traditionally used herbal medicine

Helicobacter pylori (H. pylori) infection leads to different clinical and pathological outcomes in humans, including chronic gastritis, peptic ulcer disease and gastric neoplasia and even gastric cancer and its eradiation dependst upon multi-drug therapy. The most effective therapy is still unknown and prompts people to make great efforts to find better and more modern natural or synthetic anti-H. pylori agents. In this report 21 randomly selected herbal methanolic extracts were evaluated for their effect on inhibition of Jack-bean urease using the indophenol method as described by Weatherburn. The inhibition potency was measured by UV spectroscopy technique at 630 nm which attributes to released ammonium. Among these extracts, five showed potent inhibitory activities with IC50 ranges of 18-35 μg/mL. These plants are Matricaria disciforme (IC50:35 μg/mL), Nasturtium officinale (IC50:18 μg/mL), Punica granatum (IC50:30 μg/mL), Camelia sinensis (IC50:35 μg/mL), Citrus aurantifolia (IC50:28 μg/mL).