ABSTRACT
Background and Objective: The adoption of methods for increasing the shelf life of dairy products by using natural preservatives is necessary. This study was done to determine the antimicrobial activity of aqueous extract of orange peel and its effect on the shelf life of flavored milks
Methods: In this descriptive-analytical studty the antimicrobial activity of aqueous extract of orange peel was investigated by using disk diffusion method and minimum inhibitory concentration [MIC] by successive dilution of culture broth and then its impact on the shelf life of milk
Results: In disk diffusion method and MIC the antimicrobial effect of aqueous extract of orange peel was more effective against Staphylococcus aureus and Candida albicans and less effective on Escherichia coli. The growth diameter of disk diffusion method in aqueous extract of orange peel was 7.11, 29.06 and 50 mm for Staphylococcus aureus, Escherichia coli and Candida albicans, respectively. The inhibitory concentration in the aqueous extract of orange peel was 15, 2 and 2 mg/ml, respectively. Also 0.17 g/ml of aqueous extract of orange peel in milk reduced the growth of microorganisms at the time of 6, 12, 24, 48 and 72 hours. Temperature affected the growth of Candida albicans in the milk, so that the growth of microorganisms reduced with decreasing temperature [P<0.05]. The growth inhibitory activity of the aqueous extract of orange peel on Staphylococcus aureus was significantly more than on Escherichia coli [P<0.05]
Conclusion: This study showed that the antimicrobial activity of aqueous extract of orange peel on Staphylococcus aureus, Escherichia coli and Candida albicans in vitro and in the milk
ABSTRACT
To compare intraocular pressure [IOP] measurement with Pulsair non-contact tonometer and Goldmann applanation tonometer [GAT]. In this cross-sectional study, during a complete ophthalmologic examination, each patient underwent Pulsair tonometry three times at 5 minutes intervals and then Goldmann tonometry at the same intervals. Mean IOP values were measured and analyzed. We evaluated 458 eyes of 250 patients [138 males and 112 female subjects]. Mean IOP was 19.45 +/- 9.04 mmHg with GAT and 20.11 +/- 8.42 mmHg with Pulsair [P=0.075]. Correlation coefficient between the two methods was 0.96 [P= 0.004] and the mean difference [Pulsair-GAT] was 0.65 +/- 1.52 [confidence interval 95%, +3.5 to -2.29]. With IOPs between 10-25mmHg, mean difference between the two methods was 0.49 +/- 1.23 [P= 0.32] mmHg, however it was -1.75 +/- 1.91 [P= 0.06] at IOPs over than 25 mm Hg. Pulsair tonometry has acceptable accuracy in comparison with GAT, especially in IOP ranging from 10 to 25 mmHg