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Background and objectives: Given the growing prevalence of obesity in children, the present study aimed to investigate effects of continuous and interval aerobic training on insulin resistance index and serum cortisol levels of obese girls.
Methods: The study was performed on 36 healthy girls aged 9-11 years with a body mass index (BMI) of higher than 85th percentile. The subjects were randomly divided into three groups of interval training, continuous training and control. The training groups performed exercises three days a week for eight weeks. The exercises were performed at 70% of VO2max in the first four weeks and at 80% of VO2max in the following weeks. Fasting blood samples were taken 72 hours before the first session and 72 hours after the last training session in order to measure levels of cortisol, glucose, insulin and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR).Weight, BMI and body fat percentage were also measured by conventional methods. Data analysis was performed in SPSS 21 using paired t-test and one-way analysis of variance.
Results: The mean level of BMI and body fat percentage decreased significantly after the interval and continuous training, respectively (P<0.05). The HOMA-IR index did not change significantly in the study groups (P>0.05). The cortisol level increased slightly in the continuous training and control groups (P=0.075) and decreased insignificantly (P=0.131) in the interval training group. There was no difference between the training groups and the control group in terms of HOMA-IR and cortisol levels.
Conclusion: Insulin levels, HOMA-IR showed a decrease trend while a reasonable increase in cortisol level we showed in the continuous training group. BMI level and fat percentage decreased in two both training groups.

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Introduction: The poultry industry produces a large amount of waste, including chicken feathers, which are difficult to decompose and can cause environmental pollution. Keratinase enzymes, which can break down keratin, have the potential to be used in bioremediation of poultry waste. The objectives of this study were to screen for keratinolytic isolates from poultry waste, Identify the isolates using morphological, biochemical, and molecular methods; optimize the culture medium conditions for keratinase production and measure the keratinase activity of the isolates.
Materials and Methods: Two keratinolytic isolates were screened from poultry waste around Mashhad in Iran. The isolates were identified using morphological, biochemical, and molecular methods. The culture medium conditions for the two strains were optimized to enhance keratinase production. The keratinase activity was measured using azokeratin substrate and turbidity absorbance.
Results: The two isolates were identified as Bacillus pumilus and Bacillus teqlensis. The optimized culture medium conditions for keratinase production were pH 7.0, temperature 37°C, and incubation time 48 hours. The maximum keratinase activity of the two isolates was 120 U/mL and 100 U/mL, respectively.
Conclusions: The two Bacillus isolates have the potential to be used in bioremediation of poultry waste. The optimized culture medium conditions can be used for large-scale production of keratinase enzymes.
The keratinase enzymes produced by the two Bacillus isolates have the potential to be used in a variety of applications, including bioremediation of poultry waste, production of animal feed, and development of new cleaning products.