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Abstract The aim of this study was to investigate the effects of yerba mate (Ilex paraguariensis St. Hil.) extract (YME) on oxidative stress parameters and pathological changes in the lungs of mice chronically exposed to hand-rolled cornhusk cigarette (HRC) smoke. Twenty-four male Swiss mice were divided into four groups exposed to the following treatments: control (ambient air), HRC, YME, and HRC plus YME. The animals were exposed to four HRCs per session, with 3 sessions/day, every day for 30 days. Twenty-four hours after the last inhalation, the mice were killed, and the left lungs were removed. The results showed that HRC contains elevated levels of tin and carbon oxide, but less arsenic, cobalt, manganese, and selenium than commercial cigarettes. YME administration reversed fibrosis, alveolar enlargement, and hemorrhage induced by HRC smoke. In addition, the YME and HRC significantly reduced the production of oxidants, oxidative damage and promoted a significant increase in total thiol. In conclusion, exposure to HRC smoke compromised pulmonary histoarchitecture by promoting structural changes and increasing oxidative stress in tissues. However, concomitant treatment with YME regulated the redox state and reduced the harmful effects of HRC smoke exposure in the lungs.

ABSTRACT The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.