Antimicrobial

Red onion extract is rich of phenol and flavonoid component which has many application in food, cosmetic and pharmaceutical industries. This study aims to investigate the effect of maceration and ultrasonic methods on antimicrobial activity and antioxidant properties of ethyl acetate and n-butanol extract of red onion skin. The results showed that the ethyl acetate extract obtained by ultrasonic method had the highest content of total phenols and flavonoids with averages of 439.45 mg equivalent of gallic acid per gram of extract and 33.44 mg equivalent of quercetin per gram of extract, respectively. The highest DPPH scavenging activity, reducing power and nitric oxide scavenging activity was obtained in ethyl acetate extract extracted by sonication. Comparison of the results of the effect of extraction method on the antimicrobial properties of n-butanol extract showed that the extract obtained by maceration method at low concentrations had more antibacterial properties than the extract obtained by ultrasounic method against all microorganisms except Aspergillus niger (p <0.05). Ethyl acetate extract obtained by ultrasounic at all concentrations except 6.25 μg/ml had a significantly greater effect on Staphylococcus aureus and Escherichia coli and Candida albicans (p <0.05). Based on the results obtained in the present study, extraction with ethyl acetate by ultrasonic method had the best results in terms of antimicrobial and antioxidant activity.

Medicinal plants have been used since ancient times as a source for treating diseases. Nettle (Urtica dioica) possesses anti-inflammatory, diuretic, antihistamine, antimicrobial, and immune-boosting properties.. The aim of this study was to investigate the antimicrobial effect of nettle leaf aqueous extract using agar disc diffusion, agar well diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods against a number of Gram-positive and Gram-negative bacteria. Results from agar disc diffusion and agar well diffusion tests showed that the most sensitive and resistant fungal strains to nettle leaf aqueous extract were Staphylococcus aureus and Salmonella typhi, respectively. As the concentration of nettle leaf extract increased, the zone of inhibition for all tested fungal strains significantly increased. The results indicated that the minimum inhibitory concentration for gram-negative bacteria such as Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa was 128, 256, and 256 mg/ml, respectively, and for gram-positive bacteria including Listeria innocua, Staphylococcus aureus, and Bacillus cereus was 128, 64, and 128 mg/ml, respectively. The minimum bactericidal concentration for all tested strains was greater than 512 mg/ml. This study suggests that nettle leaf aqueous extract can be used as a natural antimicrobial compound in the food industry or in the treatment of certain infectious diseases.

German chamomile (Matricaria chamomilla L.) is a well-known medicinal plant that is distributed worldwide and is widely used in traditional medicine for the treatment of various diseases. In this study, the essential oil of M. chamomilla was extracted by water distillation method and its total phenol content, total flavonoid content, antioxidant activity, and antimicrobial effect were investigated. The total phenol content of the essential oil was 39.70 mg GAE/g and its total flavonoid content was 18.80 mg QE/g. The antioxidant activity of the essential oil was evaluated based on two methods of inhibiting free radicals DPPH and ABTS; the essential oil was able to inhibit free radicals DPPH (58.60 %) and ABTS (61.60 %). The antimicrobial effect of the essential oil against Bacillus cereus, Streptococcus pyogenes, Staphylococcus aureus, Shigella dysenteriae, Enterobacter aerogenes, and Salmonella typhimurium was investigated by disk diffusion agar, well diffusion agar, minimum inhibitory concentration, and minimum bactericidal concentration. The findings of the antimicrobial activity of the essential oil by the disk diffusion agar and well diffusion agar, showed that S. pyogenes and E. aerogenes were the most sensitive and resistant microbial strains to M. chamomilla essential oil, respectively. The results of this study showed that the essential oil of M. chamomilla has shown strong antioxidant and antimicrobial activity, which can be a potential candidate for the preparation of antioxidant and antimicrobial drugs.

The present study investigates the potential medicinal and health benefits of the Middle Eastern and North African herb Pistacia atlantica. Research shows that its compounds, such as flavonoids, phenolic compounds, and oils, could be beneficial. It can help with heart disease, sugar sickness, and brain illness because of its antioxidant and anti-inflammatory attributes. Also, P. atlantica can kill bacteria and help heal cuts. It might help fight cancer too. But we need to study more to know all its uses, enhance extraction techniques, and make sure it's safe and works well in tests with people. The review will focus on the pharmacological properties, constituents, and mechanisms of action of P. atlantica, discussing its traditional use in medicine, effects on inflammatory diseases, antibacterial properties, promise in cancer treatment, and potential for treating diabetes and other metabolic issues. The review aims to comprehensively understand P. atlantica's potential as a therapeutic agent and identify areas for further research.

Nowadays, antibiotic resistance is increasing in all parts of the world and is emerging and expanding globally. Due to their natural antimicrobial properties and low tendency to develop bacterial resistance, antimicrobial peptides can be a good candidate as an alternative to synthetic antibiotics. Bioactive peptides are produced using enzymatic hydrolysis by enzymes extracted from microorganisms and plants, digestive enzymes, and fermentation by proteolytic starter cultures. Enzymatic hydrolysis of proteins is performed by commercial proteases or a combination of several proteolytic enzymes. Commercial proteases are expensive due to their specificity. Among the strategies for protein hydrolysis with the aim of obtaining bioactive peptides is microbial fermentation, which is more environmentally friendly and has a high potential for use in industry due to its relatively low cost compared to commercial enzymes. It is a suitable method for the hydrolysis of sesame meal protein. Bacillus species are bacteria that have high proteolytic activity and are able to produce different endopeptidases in the fermentation medium. The activity of endopeptidases in the environment containing proteins causes the production of peptides with small sizes and free amino acids in higher amounts compared to enzymatic hydrolysis, which is one of the advantages of using Bacillus species with high proteolytic activity compared to pure enzymes. In general, the purpose of this research was to produce sesame meal protein hydrolysate by fermentation with Bacillus subtilis and to investigate its antimicrobial and antioxidant activity.

In this study, at the first step, sesame meal was defatted with hexane at a ratio of 1:5, then it was dried and sesame meal protein isolate was extracted, and the optimization of fermentation conditions was determined by the response surface methodology (RSM). Independent variables, including temperature (30 to 45 ˚C), time (12 to 36 h), and substrate concentration (2 to 6%), were considered. The antioxidant properties of the treatments, including DPPH radical scavenging activity, ferric ion reducing power, and antimicrobial activity, were investigated, and the optimum treatment was selected. Then the protein hydrolysate was freez-dried and stored at -20 °C.

According to the results, temperature (39.68 °C), time (30.07 h), and substrate concentration (4.85%) were selected as optimum conditions. Under these conditions, DPPH radical scavenging activity and ferric ion reducing power of hydrolysate were 63.57% and 0.9951 (absorbance at 700 nm), respectively. The inhibition percentages of Staphylococcus aureus (59.58%), Escherichia coli (6.55%), Listeria monocytogenes (62.43%), and Clostridium perfringens (50.97%) were obtained in the optimized condition. Bacillus subtilis, in the presence of sesame meal protein, showed significant (p<0.05) protease activity over time. After 48 hours, the clear zone diameter was determined to be 22 mm. The clear zone created by this strain showed that Bacillus subtilis has high proteolytic activity and can be a suitable bacterium for hydrolyzing sesame meal protein with the aim of obtaining hydrolysates with the highest antimicrobial and antioxidant activities. The antimicrobial activity of the protein hydrolysate can be due to the higher degree of hydrolysis. By increasing the hydrolysis time, peptides with low molecular weight are produced, which cause better interaction with the microbial cell membrane, disrupt the membrane, and lead to the inhibition of the microorganism. According to the results, the sesame meal protein hydrolysate showed more inhibitory effect against gram-positive bacteria than gram-negative bacteria (Escherichia coli). Researchers reported that the difference in sensitivity to antimicrobial compounds between gram-positive and gram-negative bacteria can be attributed to the structure and composition of the cell envelope (cytoplasmic membrane or outer membrane, and cell wall). In general, the bioactivity properties of protein hydrolysate depend on the amino acid composition, sequence, and molecular weight of the amino acids. The antioxidant activity can be due to the high content of polar and aromatic amino acids. By further hydrolysis of proteins, peptides and polar free amino acids are produced that interact with free radicals and converted into safe and stable intermediate products.

In this study, Bacillus subtilis strain was used to ferment sesame meal protein, which is a rich source of protein, to produce protein hydrolysate with maximum antimicrobial and antioxidant activities. Results showed that the protein hydrolysate obtained from sesame meal protein isolate had antimicrobial and antioxidant activities. It can be used as a natural antimicrobial or antioxidant agent in the formulation of food or pharmaceutical industry to improve the health of society.

Recent attention has been drawn to consuming probiotic-rich foods to enhance health and prevent diseases. Lactic acid bacteria are commonly used in fermenting foods due to their high potential to create aroma and flavor, inhibit pathogens, and prevent spoilage microorganisms. Probiotic strains commonly used belong to Lactobacillus and Bifidobacterium genera, both Gram-positive bacteria. Lactic acid bacteria are recognized for their significant presence in food items and potential use as protective cultures due to their specific attributes. These bacteria are part of the human gut microbiota, playing crucial roles in microbial balance and immune modulation (Alizadeh Behbahani et al., 2019; Alizadeh Behbahani et al., 2023; Alizadeh Behbahani et al., 2020; Fallah et al., 2021a; Fallah et al., 2021b). The primary requirement for developing a probiotic food product is selecting a suitable probiotic strain. Indigenous strains of lactic acid bacteria have gained particular importance in dairy industries due to their compatibility with regional conditions and ability to produce desirable flavors and aromas in fermented products. This research aims to evaluate the probiotic and antibacterial properties of Lpb. plantarum MOHA1 strain, including acid and bile tolerance, antibiotic resistance, cholesterol absorption, anti-adhesive properties, hydrophobicity, auto-aggregation, cell adhesion potential to Caco-2 cells, biogenic amine production, DNase activity, lack of hemolytic activity, and antioxidant activity. Additionally, the strain's antimicrobial efficacy against six foodborne pathogens (Bacillus cereus, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, Salmonella typhimurium, and Enterobacter aerogenes) was assessed.

The research process was comprehensive and rigorous. Firstly, the Lpb. plantarum MOHA1 strain was isolated and identified using molecular methods. Subsequently, the strain was evaluated for a wide range of probiotic properties, including acid resistance (pH 2, 3, and 4), hydrophobicity, and bile resistance (0.3, 0.5, and 0.7). Cholesterol absorption was also assessed. Additionally, the strain underwent evaluation for biogenic amine production and hemolytic and DNase properties. The antioxidant property of the isolated strain (measured using DPPH and ABTS assays) was determined, and its antimicrobial activity against six foodborne pathogenic bacteria (Escherichia coli, Bacillus cereus, Salmonella typhimurium, Enterobacter aerogenes, Staphylococcus aureus, and Listeria monocytogenes) was investigated using disc diffusion and agar well diffusion methods. Furthermore, adhesion potential to Caco-2 cells, anti-adhesion properties, auto-aggregation capacity, and co-aggregation of the strain were also evaluated.

The findings of this study have significant implications for the development of probiotic food products. One of the crucial criteria in evaluating the potential of probiotic strains is assessing their resistance to acidic conditions and high concentrations of bile salts. According to the World Health Organization, probiotics must be consumed sufficiently to demonstrate their beneficial effects. Conditions such as acidic pH can disrupt metabolism and reduce the growth and survival of lactic acid bacteria. The acids present in the human stomach degrade biological molecules such as fatty acids, proteins, vitamins, and nucleic acids. In this study, bile salt concentrations of 0.3%, 0.5%, and 0.7% (W/V) were tested to evaluate the resistance of the targeted strain. The results indicated that Lpb. plantarum MOHA1 has good resistance to different concentrations of bile salts. These findings are consistent with other studies that have shown lactobacilli can survive in high bile salt concentrations (Brezgár et al., 2021; Abushelaibi et al., 2017; Boricha et al., 2019; Molavi et al., 2019; Oulahal et al., 2018; Shahata et al., 2016). To assess the viability of Lpb. plantarum MOHA1, this bacterium was subjected to pH levels 3, 2, and 4. The results showed that the strain Lpb. plantarum MOHA1 has desirable viability under the examined conditions. However, the highest strain viability reduction was observed after 3 hours at pH 2. With a decrease in pH from 4 to 2, a significant reduction in the number of viable cells was observed, decreasing from 7.7 to 2.6 Log CFU/mL. Lactobacillus plantarum converts sorbic acid into 1,3-pentadiene through decarboxylation and produces carbon dioxide and ethanol during fermentation. It can also metabolize sugar compounds and produce acidic compounds such as succinic acid, which lowers the pH level (Ghorbani et al., 2018).Hydrophobicity is one of the important factors for bacteria regarding their adherence to various surfaces. Hydrophobicity depends on various factors such as van der Waals forces, Brownian motion, surface electric charge, and gravitational force. Therefore, this feature should be separately investigated for bacteria (Noshad et al., 2021). The hydrophobicity level of the Lpb. plantarum MOHA1 strain was determined to be 20.53% ± 0.60%. In a comprehensive study by Vosoughi et al. (2018), it was reported that Lpb. plantarum A44 isolated from whey exhibited the highest cellular hydrophobicity (84.5%) among other strains. In the study by Alizadeh Behbahani et al. (2019), the Hydrophobicity potential of the Lpb. plantarum L15 strain was found to be 54%. In the research conducted by Shahrampour et al. (2019), the effect of genetic diversity of Lpb. Plantarum strains isolated from different food sources were investigated for their antimicrobial, antioxidant, and cumulative activities. The results showed that the strain Lpb. plantarum KMC61 had the highest surface hydrophobicity percentage. However, there was a difference in surface hydrophobicity among the ten strains studied, which may be related to the biosynthesis and composition of their cell surface proteins and polysaccharides. The production of biogenic amines, DNase, and hemolytic activity were negative. In this study Cholesterol absorption was 40.30%. Many studies have shown that some lactic acid bacteria in cell culture media can reduce cholesterol concentration. In some studies, changes in the fatty acid pattern inside the cell have been observed following this reduction. In some cases, microscopic examination of the cell has shown deposition and binding of cholesterol to the bacterial surface. The presence of such strains as starter cultures in foods considered a source of cholesterol can be very beneficial (Modani et al., 2013).DPPH radical scavenging activity was 45.80%, and ABTS radical scavenging activity was 48%. The antimicrobial and antioxidant properties of Lpb. plantarum strains have been reported in various studies. Asadi et al. (2009) investigated the technological characteristics and antimicrobial activity of 17 strains of Lpb. plantarum isolated from a type of salted meat, and observed the highest inhibitory activity of Lpb. plantarum strains against Staphylococcus aureus bacteria. Auto-aggregation potential was 37.60%, and co-aggregation potential was 19.10%. The adhesion potential to Caco-2 cells was 11.30%. One of the most important criteria for selecting lactic acid bacteria as probiotics is their safety and tolerance to gastrointestinal conditions and their ability to adhere to the mucosal cells on the intestinal surface.Challenges associated with clinical studies on adhesion testing have led to the widespread use of simulated models at the laboratory scale. In particular, the use of the Caco-2 cell line for evaluating the adhesion of probiotic strains to the digestive system has gained significant attention because, under these conditions, the morphological and functional properties of cells on the surface of small intestinal villi are well-defined (Fallahi et al., 2018). Anti-adhesion potential against E. coli was 36.70% in competition, 35.50% in inhibition, and 22.40% in displacement. Pathogenic bacteria must attach to the intestinal cell wall to cause infection. Therefore, any factors that prevent this activity benefit health and intervene with the development of infection. Probiotic bacteria, through mechanisms such as producing antimicrobial compounds and disrupting or blocking molecules that pathogenic agents use for attachment, prevent the adhesion of pathogenic bacteria (Vosoughi et al., 2022). A study evaluating the probiotic potential of indigenous Lactobacillus strains isolated from Zabol yellow cheese was conducted by Vosoughi et al. (2022). The antimicrobial effect of Lpb. plantarum MOHA1, both acidic and non-acidic, on pathogenic strains has been demonstrated using the agar diffusion and well methods Showed that the greatest inhibitory effect was observed against L. monocytogenes. This bacterium is a facultative anaerobe capable of surviving in both the presence and absence of oxygen and is known to cause a wide range of diseases in humans and animals. The least inhibition was observed in the agar diffusion method using disks against the pathogens S. typhimurium and E. coli, and in the agar diffusion method using wells against the pathogen E. coli. Intestinal Gram-negative bacteria such as E. coli and S. typhimurium are among the major causes of food poisoning and diarrhea.

Strains isolated from local fermented and dairy products are considered valuable sources of probiotics. These strains have high probiotic potential and exhibit significant antimicrobial properties. According to the results of this study, Lpb. plantarum MOHA1 can withstand acidic conditions in the stomach and the presence of bile salts, indicating essential traits for survival and effective performance in the human digestive system. This strain has demonstrated a high ability to inhibit pathogenic bacteria, attributed to the production of antimicrobial compounds that can inhibit the growth and proliferation of pathogens. Additionally, Lpb. plantarum MOHA1 is sensitive to common antibiotics, which can be beneficial in controlling infections and preventing microbial resistance. Other important characteristics of this strain include its ability to adhere to the intestinal wall, surface hydrophobicity, autoaggregation, and co-aggregation. These features enable this strain to adhere to the intestinal epithelial cells and form resilient colonies, which can improve digestive health and enhance the body's immune system. Given these properties, the Lpb. plantarum MOHA1 strain has a high potential for use as a probiotic supplement in fermentation cultures or as a co-culture in the production process of fermented food products. Using this strain can help improve food products' quality and shelf life and enhance consumer health. Further confirmatory tests and comprehensive research can strengthen these strains' practical and commercial applications in the food industry.

Adding chemical preservatives increases the shelf life of food products, but long-term and indiscriminate use of chemical preservatives increases the resistance of microorganisms and health risks associated with their absorption. Medicinal plants have a great diversity both in the world and in Iran and have the potential to be used as alternatives to chemical compounds. In this study, the antimicrobial effect of Pterocarya fraxinifolia essential oil against Bacillus subtilis, Streptococcus pyogenes, Staphylococcus aureus, Shigella dysenteriae, Enterobacter aerogenes, and Salmonella typhi was investigated by disk diffusion agar, well diffusion agar, minimum inhibitory concentration, and minimum bactericidal concentration. The total phenol and flavonoid content of the essential oil was determined using Folin Ciocalteu and aluminium chloride methods, respectively. The antioxidant activity of the essential oil was evaluated using two methods of inhibiting free radicals DPPH and ABTS. The total phenol and flavonoid content of the essential oil was 38.63 mg of gallic acid/g and the flavonoid content was 19.20 mg of quercetin/g. The essential oil of P. fraxinifolia was able to inhibit free radicals DPPH (58.60%) and ABTS (59.80%). The results of the antimicrobial activity of the essential oil by the disk diffusion agar and well diffusion agar methods showed that B. subtilis and E. aerogenes are the most sensitive and resistant microbial strains to the essential oil, respectively. The minimum inhibitory concentration for these bacteria was 2 and 64 mg/mL, respectively, and the minimum bactericidal concentration was 32 and > 512 mg/mL, respectively.

Drying is one of the effective ways to increase shelf life and preserve the useful compounds of materials, which can be improved by using different methods and materials. The use of bioactive compounds as a pre-treatment can be one of the effective methods to increase functional and antibacterial properties. This research was conducted to simultaneously apply ultrasonic pretreatment and pure apple vinegar before drying garlic slices, and investigate their effect on the functional and antibacterial properties of dried garlic slices by hot air. Before drying, the slices were floated in pure apple vinegar and distilled water under ultrasonic treatment (frequency of 40 kHz) for 10 minutes at 35oC, and also in pure apple vinegar for 10 minutes at 35oC. Then they dried using a hot air circulation dryer at a temperature of 50oC to reach a moisture content of 6% (wet basis). The chemical properties of samples including total phenolic and flavonoid content, functional properties, antioxidant capacity, and antibacterial properties were evaluated. The results showed that the use of ultrasound pretreatment together with pure apple vinegar had the greatest effect in the increase of bioactive compounds and antibacterial properties of samples compared with the control one. The results showed that the use of ultrasonic and pure apple vinegar improved the quality, functional, and antibacterial properties of dried sliced garlic samples.

The use of medicinal plants in food has a long history. Flaxseed oil and eucalyptus essential oil are highly regarded due to their biological properties. In this research, the aim is to investigate the antimicrobial properties of zein nanofibers containing flaxseed oil and eucalyptus essential oil to control staphylococcus aureus and escherichia coli bacteria in a laboratory environment. For this purpose, flaxseed oil mixed with eucalyptus essential oil in zein solution. Then, it was converted into nanofibers using an electrospinning machine. In order to study the characteristics and antimicrobial properties of the nanofibers, tests including scanning electron microscopy (SEM), fiber diameter determination with Image J software, atomic force microscopy (AFM), X-ray diffraction (XRD), thermal gravimetric analysis (TGA) were performed. Investigation of antimicrobial properties of produced nanofibers by disk diffusion method were performed. The SEM results showed that the morphology of the electrospun fibers was uniform and free of beads. AFM images represented three-dimensional and tubular images of fibers obtained from electrospinning zein/flaxseed oil/eucalyptus essential oil. The X-ray diffraction pattern showed an increase in the crystallinity intensity of the treatments compared to the control sample. Based on thermal analysis results, eucalyptus and flaxseed oil increased the thermal stability of zein nanofibers. The results showed that the addition of flaxseed oil to eucalyptus essential oil strengthened the antimicrobial properties of nanofibers. According to the results of the present research, the zein/flaxseed oil/eucalyptus essential oil fibers can be used as natural antimicrobials.

Extracts and essential oils of medicinal plants have many bioactive agents, including phenolic compounds with significant antioxidant and antimicrobial properties. Choosing the suitable extraction method affects the quantity and quality of antioxidant and antimicrobial compounds. The aim of this study was to evaluate the efficiency of ultrasound waves in extracting phenolic, antioxidant and antimicrobial compounds of Caper fruit. Response surface methodology (RSM) and Box–Behnken design were used to optimize the extraction factors, including extraction time (10, 25, 40 min) and ultrasound intensity (40, 70, 100 %) with ethanolic solvent (70 %). From the results of the tests performed with the response surface methodology, ultrasound intensity was recognized as the most effective factor in extracting phenolic, antioxidant and antimicrobial compounds of Caper fruit and by increasing time and ultrasound intensity, the extraction of these compounds increased. The optimum conditions for extraction of antioxidant and antimicrobial compounds of Caper fruit were determined extraction time 36 minutes and ultrasound intensity 91 percent. In these optimum conditions, the amount of total phenolic contents and IC50 index of ethanolic extracts extracted from Caper fruit were obtained 23.63 mg/g and 45.30 μg/mg, respectively, the optimum amount of minimum inhibitory concentration of coagulase positive Staphylococcus aureus and Bacillus cereus were obtained 0.19 and 6.07 mg/ml, respectively, and the optimum amount of minimum batericidal concentration of coagulase positive Staphylococcus aureus was obtained 11.81 mg/ml. Also, the extracts extracted at time 36 minutes and ultrasound intensity 91 percent had the ability to inhibit the activity of Escherichia coli O157: H7 and Pseudomonas aeruginosa at concentrations of 25 and 25 mg/ml, respectively, and had the batericidal ability of Bacillus cereus, Escherichia coli O157: H7 and Pseudomonas aeruginosa at concentrations of 25, 50 and 50 mg/ml, respectively.

Today, the use of active packaging containing natural antimicrobial compounds such as essential oils and plant extracts has increased to increase the shelf-life of food  products. The purpose of this study is to investigate the effect of gelatin coating containing Citrus sinensis peel extract on increasing the shelf life of rainbow trout meat. Gelatin (4%) coating was prepared with different levels of Citrus sinensis peel extract (2% and 4%). After preparing the pieces of rainbow trout meat, all the pieces were coated and examined for chemical properties (pH, TVB-N, TBARS), microbial (TVCs and TPCs) and sensory properties (odor, color, texture and overall acceptance) were evaluated for 16 days at 4°C with a 4-day interval (0, 4, 8, 12, 16). The results of the investigation of the antimicrobial effect showed that in the samples coated with 2% and 4% levels of Citrus sinensis peel extract, the average count of mentioned bacteria was significantly lower than the control and gelatin alone (p < 0.05). The results of examining the chemical properties of the samples showed that pH, TVB-N and TBARS increased during the period, but this increase occurred at a slower rate in the samples coated with different levels of Citrus sinensis peel extract. In the evaluation of sensory characteristics, at the beginning of the study, all the samples had the highest acceptance limit, and with the passage of time and the appearance of signs of spoil, the scores decreased, especially in the control. Generally, the results showed that gelatin coating along with different levels of Citrus sinensis peel extract has a positive effect on increasing the shelf life of fish meat and these compounds can be used together to increase the shelf life of protein foods.

Sargassum and Padina are two genera of brown algae that are widely scattered in temperate regions. Sargassum species are categorized as tropical and sub-tropical brown seaweed which are valuable sources of bioactive compounds including dietary fibers, carotenoids, vitamins, and minerals. These brown algae demonstrate diverse biological activities such as antioxidant, antimicrobial, and anti‑Alzheimer, due to the presence of flavonoids, triterpenoids, flavonoids, sterols, polyphenols, and pheophytine. The genus Padina is scattered in many environmental conditions, mainly in the tropical marine waters, and belongs to the family Dictyotaceae. Some bioactive components isolated from Padina species have been demonstrated hypoglycemic, hypolipidemic, anti-obesity, hepatoprotective, cardioprotective, immunostimulatory, and antimicrobial activities., The aim of this study was to prepare an extract from two species of algae Padina and Sargsum by massaging and ultrasound assisted-methods  as well as analyzing their compounds and investigating the antioxidant, antimicrobial and enzymatic properties of the extracts. According to the obtained results, ultrasound assisted method was a suitable method for extraction. This extract can be used as a combination of antioxidant, antimicrobial, anti-Alzheimer's and nitrate reducing agent in food additives.

Chemical materials were supplied by Sigma-Aldrich GmbH (Sternheim, Germany). The algal species utilized in the current investigation; namely, Padina distromatic and Sargassum angustifolium were collected from the coastal region of Chabahar bandar, Sistan and Baluchistan Province, Iran. To eliminate all the impurities and extraneous materials, they were washed by using distilled water and then dried at ambient temperature (24-48 h) until the constant weight. Extraction by maceration was compared with the extraction using ultrasonic assisted method. Determination of chemical compounds was parformed using GC-MS device. Investigation of antioxidant properties and total polyphenol and flavonoid content were also performed. The degree of free radical scavenging was done according to DPPH method. Evaluation of antimicrobial effect of algae extracts were the main challenges in our research. S. aureus ATCC25923, Listeria innocua ATCC 33090, E. coli ATCC 25922 and S. typhi ATCC 6539 were used for antimicrobial test. Determination of minimum growth inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were performed using wells in agar.The enzymatic activity was also determined. In this study, the activity of acetylcholinesterase was investigated using the method introduced by Ellman et al. (1961) and also the activity of nitric oxidase was determined using a kit protocol (Nvand-Iran). Factorial experiment in the form of a completely randomized design was used to analyze the data. Duncan's multiple range test was used to determine the difference between the means at the 95% confidence level, and SAS software version 2.9 will used for statistical analysis.

The current study investigated the antioxidant, antibacterial, anti-inflammatory, and anti-Alzheimer’s attributes of two brown algae namely Padina distromatic and Sargassum angustifolium which were collected from the coastal region of Chabahar Bandar, Iran. The results clearly indicated that the type of algae and extraction techniques used in this investigation highly affected phytochemical compositions, antioxidant, AChE inhibitory, scavenging, and antimicrobial activities. Considering both extraction yield and phytochemical components, extraction by ultrasound assisted method provided better results. Among all algal extracts, UPE presented the highest AChE inhibitory activity, and antibacterial activity and USE presented the highest antioxidant activities, total phenols and flavonoids, reflecting the presence of various bioactive components. The extracts of two various seaweeds utilized in the current study highlighted considerable inhibitory action against four pathogenic bacteria. According to the observations of the antibacterial assay, S. aureus was the most sensitive microorganism, while L. innocua was revealed as the most resistant bacteria to the extracts of P. distromatic and S. angustifolium. Further, the chemical components responsible for the antioxidant, AChE inhibitory, and antibacterial power were confirmed by GC-MS analysis. The findings of the current investigation confirmed the potential of the health benefits and therapeutic effect of brown marine algae. Thus, the extract of P. distromatic and S. latifolium could be an effective supplement to be incorporated into the products’ formulation in the food and pharmaceutical industries as well as in medication to alleviate several disorders such as Alzheimer.

During the current research, a traditional nomadic Iranian dairy product named Masineh was produced, which is prepared from heated yogurt drink and herbal additives including turmeric, dill seed powder and cumin. Some physicochemical and microbial characteristics of Masineh samples were investigated during 21 days of storage at 4°C. In addition, the antioxidant properties, antimicrobial effects and organoleptic properties of the product were investigated and compared with the control sample (heated yogurt drink without additives). The results showed that herbal additives significantly reduced the counts of bacteria, mold and yeast in Masineh compared to the control sample (P<0.05). In Masineh, the highest inhibitory effect was observed against Staphylococcus aureus with 30.91 mm, and the lowest inhibitory effect was observed against Escherichia coli with an average of 15.50 mm, followed by Aspergillus niger with an average of 18.12 mm. In addition, the phenolic compounds and DPPH and ABTS inhibition percentages were higher in Masineh than control sample. The pH and viscosity of Masineh were higher than that of drinks without additives, and during storage, these values decreased significantly (P<0.05). Also, the results of the sensory evaluation showed that the sensory evaluators considered the taste of the masineh to be favorable and did not report a significant difference with the control sample in terms of overall acceptance, although the color of the masineh had a lower score. Therefore, according to the obtained results, Masineh is introduced as a beneficial dairy drink, in which by the use of herbal additives, its antioxidant properties and microbiological properties are strengthed.

The present study aimed to encapsulate thymol and resveratrol prepared with zein-caseinate composite nanoparticles and to investigate their antioxidant and antimicrobial properties. For this purpose, liquid-liquid dispersion method was used to prepare zein-caseinate composite nanoparticles. In this study, the effect of different concentrations ratio of thymol and resveratrol (zero to 100%) and different ratios of core to coating (1:10 and 1:20) on the ability to inhibit DPPH free radicals, the reducing power of iron ions and antimicrobial activity on Escherichia coli and Listeria monocytogenes was investigated in culture media and milk. The results showed that the sample containing 75% thymol and 25% resveratrol with a ratio of 1 to 10 of core to coating had the highest ability to inhibit DPPH free radicals and the reducing power of iron ions, and it was found that the increase in the coating concentration except for the sample containing 75% thymol, led to an increase in the Inhibition power of DPPH free radicals and reducing power of iron ion. Listeria bacteria in the TSB culture medium were the most sensitive bacteria to the prepared samples, and the strongest prepared nanoparticles, which had the lowest MIC and MBC, belonged to the sample containing 75% thymol and 25% resveratrol with a core-to-wall ratio of 1:10, and in most samples, The bacteria in milk were more resistant to these nanoparticles than the culture medium. Finally, it can be said that the sample containing 75% thymol and 25% resveratrol with a core-to-wall ratio of 1 to 10 can be selected as a combination with appropriate antioxidant and antimicrobial power.

Meat and their products are highly sensitive to microbial growth and lipid oxidation development, which lead to economic losses and health hazards (Kiarsi et al., 2020). Edible coatings are currently receiving a great deal of attention as novel food packaging to increase the quality and shelf-life of various food products through preventing physical, chemical, and biological deteriorations (Barzegar et al., 2020). Okra (Ablemoschus esculentus) is an annual plant and rich in valuable nutrients such as vitamins and elements such as phosphorus, manganese, potassium and calcium and also contains phytosterols, tannins and carbohydrates. Okra contains large amounts of viscous gum with a thickening property. Edible coatings are able to carry active compounds such as antioxidants and antimicrobials, as well as nutrients and essential oils (Ashrafi Yorganloo and Gheybi, 2018). Peppermint (Mentha piperita) is one of the most widely used medicinal plants due to biological effects of its main components, especially menthol. Its essential oil is used as a flavoring in chewing gum, mint chocolate, medicines and toothpaste (Kazem Alvandi et al., 2010). The antimicrobial and antioxidant properties of peppermint essential oil have been investigated. To the best of our knowledge, there is no report in the literature regarding the effect of edible coating of Okra gum containing peppermint essential oil on meat quality and shelf life during refrigeration. This study is therefore aimed to develop a novel edible coating based on Okra gum-peppermint essential oil to improve the shelf life of buffalo meat slices.

Peppermint essential oil and Okra were purchased from Dezful and Ahvaz, respectively. The chemical compounds of the essential oil were identified and quantified by a gas chromatography coupled to a mass spectrometer. The total phenol content (Noshad et al., 2020), total flavonoid content (Rahmati‐Joneidabad and Alizadeh Behbahani, 2021), ABTS-radical scavenging effect (Hojjati and Alizadeh Behbahani, 2021), antimicrobial effect (Disc diffusion agar, well diffusion agar, and minimum inhibitory/bactericidal concentration) of the essential oil were determined. The oil (0, 0.5, 1, 1.5, 2%) was then added to Okra gum solution to prepare edible coatings for buffalo meat coating purposes. The physiochemical (pH, moisture content, peroxide value, and hardness), microbial (Total viable count, psychrotrophic count, E. coli, S. aureus, and Fungi count), color (L*, b*, and a*), and sensory (odor, color, appearance, texture, and overall acceptance) of buffalo meat slices were evaluated during storage period (10 days, 4 °C).

The essential oil contained menthol (47.17%) and menthone (23.29%) and its total phenolic content, flavonoid content, and ABTS radical scavenging effect were 77.20 mg GAE/g, 47.50 mg QE/g, and 62.60% respectively. The essential oil was also able to inhibit the growth of P. aeruginosa, E. coli, S. aureus, B. cereus, and B. subtilis. The functional groups of the compounds of peppermint essential oil were observed at 2955, 2923, 2870, 1711, 1455, 1369, 1247, 1044, 993, and 887 cm-1. The edible coating was able to prevent the pH increase in buffalo meat samples during storage. The control and samples coated with Okra gum containing 0, 0.5, 1, 1.5, and 2% essential oil had 11.26, 11.40, 6.40, 4.51, and 4.39% water loss during storage. The peroxide value of control and Okra gum+2%essential oil coated samples were increased by 7.33- and 2.28-folds, respectively, as the storage time increased up to 10 days. The lower oxidation development in the coated samples could be probably due to the low oxygen permeability of the coating and the antioxidant activity of the essential oil. Although the hardness of samples decreased during storage, the essential oil-rich coated samples had remarkably higher hardness values compared to the control sample, likely due to the inhibitory effect of the essential oil against the activity of endogenous proteolytic enzymes of the buffalo meat. The edible coatings loaded with higher concentration of the oil were more effective in inhibiting microbial growth in buffalo meat samples during cold storage. This could be attributed to the antimicrobial effect of the essential oil and the oxygen-barrier function of the edible coating. The L* and b* of the coated samples were also higher in comparison to the non-coated sample; whilst, they were generally less red, probably due to myoglobin conversion to metmyoglobin under low-oxygen pressure conditions of the edible coating, along with exudate accumulation in the coated buffalo meat samples. The coated samples with higher essential oil concentrations were also generally more acceptable in term of sensory properties. Generally, the sensory attributes were in good agreements with the chemical and microbial results; the lower the microbial growth and oxidation, the higher were the sensory properties.

The Okra gum-peppermint essential oil based edible coating could be introduced as a novel edible coating to inhibit the microbial growth and lipid oxidation of buffalo meat and increase its shelf-life and other food products. Keywords: Antimicrobial, Antioxidant, Chemical composition, Edible coating, Okra gum, Peppermint essential oil, Shelf-life.

Today, due to its environmental problems and importance, the use of biodegradable nanocomposite films is of particular importance. In this study, silver nanoparticles were synthesized by means of aqueous extract of Mentha and the adsorption capacity of 1,1-diphenyl- 2-picrylhydrazyl radicals and their antimicrobial activity should investigated by the method of determination of minimum inhibitory concentration. The uniformity and shape were structure of these nanoparticles was determined by scanning electron microscopy. The antimicrobial effect of starch-based nanocomposite films, together with these nanoparticles, was investigated by disk diffusion test and determination of minimum inhibitory concentration of nanoparticles by threeEscherichia coli, Staphylococcus aureus and Listeria monocytogenes. The results showed that silver nanoparticles showed the highest absorption at 430 nm and had a spherical shape and their average size was between 15-37 nm. The silver nanoparticles produced acted as DPPH radical inhibitors (IC50 = 170 μ M). The minimum growth inhibitory concentration and the minimum lethal concentration on Staphylococcus aureus showed 3.1 and 6.2 showed the highest minimum inhibitory concentration. Also, by measuring the diameter of the bright area by the disk penetration test, pure starch does not have antimicrobial properties, but by adding 250 ppm silver nanoparticles to the starch film in the presence of bacteria, a halo with a diameter of 2.55 cm is formed and in fact by adding nanoparticles antimicrobial properties Starch is formed in the film and again increases the diameter of the halo to 2.35 cm in the film by bringing the amount of silver nanoparticles to 500 ppm, which indicates an increase in antimicrobial properties. Starch- based biodegradable films with biosynthesized silver nanoparticles showed antimicrobial effect against all tested microbes (p <0.05).

in recent years, the use of bioactive compounds in the formulation of meat and meat products has attracted the attention of experts.This research was conducted in two phases. In the first phase, aqueous, ethanolic and hydro-ethanolic extracts of Allium sativum controversum(Varcoaz) andMentha pulegium were extracted by soaking and the total phenols, flavonoids and antioxidant activity of the extracts were measured. The results of the first phase showed that the ethanolic extract of both plants had the highest amount of total phenol, flavonoids and antioxidant activity and as a result, this extract was selected for injection into sausage formulation at levels of 0.5, 1 and 1.5%. In the second phase, the treatments were kept at refrigerator temperature on1,15 and30 days, during which time a number of microbial tests were performed on them and a control sample (sausage without any extract). In terms of coliform count, no countable colony was observed on first day. During the 15th to 30th days, the control sample showed the highest number and the treatment containing 1.5% of Varcoaz extract showed the lowest number of coliforms. In terms of the number of Staphylococcus aureus, during the 15th to 30th days, the control sample had the highest number of this bacterium, while the treatment containing 0.5% ofAllium sativum controversum extract showed the lowest number. During the first 15 days, no countable number of molds and yeasts were observed in the studied treatments, but on 30th day, the treatment containing 1.5% of Varcoaz extract showed the lowest number of molds and yeasts and the control sample had the highest number of them.

Recently, the tendency to use probiotic-potential starter cultures among lactic acid bacteria (LAB) isolated from non-dairy fermented substrates has been increased. The aim of this study was to isolate and molecularly identify the predominant LAB isolated from fermented germinated clover seeds, and also to evaluate its probiotic and antifungal properties. The LAB isolate was identified as Pediococcus pentosaceus, in accordance with the sequencing results of the PCR products. The antifungal and antibacterial effect of the isolate on Aspergillus niger and Staphylococcus aureus was significantly (P <0.05) higher than the other studied foodborne fungi and bacteria. Furthermore, P. pentosaceus isolate had a good survival (77.22%) in simulated gastrointestinal conditions. The isolate had no hemolytic activity, and its auto-aggregation activity was 35.51%. Also, the rate of co-aggregation of the isolate with Escherichia coli and S. enterica was equal to 48.71% and 18.43%, respectively. In addition, the bacterium was sensitive to the penicillin, cephalothin, ampicillin and cefazolin antibiotics.Accordingly, it is possible to use the isolate as a probiotic culture with potential biological preservative in the food industry

This study aimed to determine antioxidant activity, total phenol, phenolic acids and minimum inhibitory concentrations of the stem bark and root of three Barberries species (Berberis integrima Bunge, Berberis vulgaris asperma and Berberis vulgaris orientalis). The root extract of Berberis vulgaris asperma showed the highest amount of total phenol and antioxidant activity. After measuring minimum inhibition concentration, the stem extract of Berberis vulgaris orientalis and the root extract of Berberis vulgaris asperma were selected as the best extract with a high level of antimicrobial activity. Also, the root extract of Berberis vulgaris asperma could effectively prevent fungal and bacterial growth in a concentration of 600 and 750 ppm. Moreover, bread containing 600 ppm of Berberis vulgaris asperma root extract showed the highest level of overall acceptability and oxidative stability. According to the results, Berberis vulgaris asperma root extract was the best extract among the studied samples and the concentration of 600 ppm was the best level for enriching bread and producing functional bread with extended shelf life.