جستجوی مقالات مرتبط با کلیدواژه « Natural Preservatives » در نشریات گروه « پزشکی »

 Today, despite improved food safety, nearly a quarter of the population is at risk for foodborne diseases. Therefore, the use of lactic acid bacteria and their metabolites due to their potential health benefits, safety and production of natural antimicrobial compounds is an appropriate solution to reduce microbial spoilage of food.

   In this research, lactic isolates were first identified by PCR method and Micro-dilution method was used to evaluate the antimicrobial activity of the Cell Free spent Medium (CFSM).

   The sequencing of PCR products showed that the species identified were Lactobacillus and Enterococcus species. The results of the evaluation of the antibacterial properties of the CFSM on the growth of Gram-positive bacteria showed that all isolates were able to prevent the growth of these pathogens and their inhibitory percentages varied from 86.81 to 38.81 percent. The results of inhibitory effects of lactic isolates on the growth of two gram-negative bacteria of Escherichia coli and Salmonella enterica also showed that the inhibitory levels of the isolates were varied from 2.43 to 36.43 percent and 14.1 to 31.97 percent, respectively. Comparison of the inhibitory effect of lactic isolates on pathogenic bacteria showed that the inhibitory effect of all lactic isolates on gram positive bacteria was significantly (P <0.05) more than their effect on gram negative bacteria.

  The results of this study showed that native dairy lactic acid isolates and their metabolites can be used as biological preservatives or in combination with synthetic preservatives in the food and drug industry.

In recent years, food manufacturers have taken a lot of attention to the use of natural preservatives instead of chemical preservatives in their products, which has led consumers to prefer to use processed food without preservatives or even with natural preservatives. The aim of the present study was to investigate the antibacterial effect of ethanolic extract of Biebersteinia multifida on the growth of food-borne bacteria on white cheese. After the plant gathering, the ethanolic extract of plant prepared, after ensuring the milk is not microbial contamination, Bacterial inoculation, Calcium chloride, extract and Enzyme added to milks and divided to five groups (control negative, positive and treatment). Survey of growth rate of bacteria did in 60 days. The results indicated that in the specimen containing the extract, the number of bacteria decreased throughout the study period compared to the non-extracting specimen. The most antibacterial effect of the extract was observed in removing or inhibiting bacterial growth in the first 24 hours. But over time, the antibacterial properties of the extract decreased and the number of developed bacteria increased. Despite the fact that the effect of inhibiting bacterial growth of the Biebersteinia multifida extract in the first 24 hours was positive, the observation of the instability of the effect of the extract of the cheese in the next stages of the experiment led to the growth of food-borne bacteria and could not be used as substitutes for chemical preservatives.

With increased resistance resulting from overusing of chemical-synthetic antibiotics, finding alternative medicines that have antibacterial properties and they have the least side effects on human health appears to be necessary. Many studies have been taken into consideration medicinal plants with antimicrobial properties. The aim of this study was to have an overview of the antibacterial properties of medicinal plants.
In this study, by searching key words as: herbs (Medicinal Plants), anti-bacterial properties of medicinal plants in Iran , antimicrobial properties of medicinal plants in Iran, in scientific articles published in databases as: Iranmedx, Magiran, Google scholar, Ebsco, Pubmed, Science direct, and SID, the required data were obtained.
Many herbs, including Zataria multifora, Urtica dioical, Crocus sativus L., Artemisia Absinthium, Menta piperita, Eucalyptus globules L., Borago officinalis L., Scrophularia desrti, Cuminum cyminum L., Rosmarinus officinalis L., Allium hirtifolium, Castaneifolia- sativa, Allium sativum, Pycnocycla spinose, Juglans Regia, Salvia officinalis L. have strong antibacterial properties against a variety of pathogenic bacteria.
In addition to the various medicinal plants with antimicrobial susceptibility and pathogenic bacteria resistance, antimicrobial properties of these studied medicinal plants could be used as a natural preservative in a variety of foods from these herbs. Thyme and garlic have antibacterial effects on an extensive range of positive and negative gram bacteria through them.

Nowadays, natural preservatives are used in food industries rather than synthetic ones. Sumac fruit (Rhus coriaria L.) is widely used as an additive in meat products due to its antimicrobial effects. This study was conducted to examine antimicrobial properties of sumac at various temperatures. In this experimental study, the extract of sumac was prepared using soaking method. Different concentrations (3.12-50 mg/ml) of the extract were used against S. aureus, L. monocytogenes, S. typhimurium, and E. coli O157:H7 bacteria. Growth assessment curve, minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC) were evaluated using microplate method. The results of this study demonstrated that MIC (6.25 mg/ml) and MBC (12.5 mg/ml) belonged to S. aureus and L. monocytogenes bacteria, respectively. The extract could significantly attenuate growth of the four bacteria at 4°C and 25°C (p<0.05). The effect of the extract on Gram-positive bacteria was significantly more than Gram-negative ones (p<0.05). Temperature reduction also affected the growth of the bacteria; at 4°C bacterial growth was less than 25°C, that is, at 6.25 concentration, S. typhimurium, and E. coli populations reduced from 3.55 log and 3.31 log to 2.14 log and 1.06 log, respectively. According to our findings, water extract of sumac is a viable alternative to chemical food preservatives, particularly at 4°C.