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The objective of this study was to evaluate the potential of Saccharomyces cerevisiae in the treatment of rice parboiling effluent (PE) and biomass production. PE was inoculated with S. cerevisiae at 1.2x104 CFU mL-1 and cultured in shaker at 28 °C and 180 rpm for 72 h. PE supplied the required nutrients for S. cerevisiae growth, reaching a biomass of ± 8.2 g·L-1, cell viability of ± 2x1011 CFU mL-1 and removals of 74%, 56% and 17% for total Kjedahl nitrogen, chemical oxygen demand and phosphorus, respectively. The versatile of S. cerevisiae supported the direct and non-supplemented cultivation in PE, resulting in high removals of nutrient and biomass production and represent an alternative method to reduce the environmental impact of rice industry and an alternative process to obtain marketable yeast biomass. [ABSTRACT FROM AUTHOR]

In this work, the use of complexing acids (HF and HCl) combined with HNO3 was carefully evaluated for the digestion of several types of lipsticks and further Cd and Pb determination by inductively coupled plasma mass spectrometry (ICP-MS). Creamy, opaque and shimmering lipsticks were digested using HNO3 (6 mL) or a mixture containing HNO3 (6 mL) plus HCl (0.5 or 2 mL) or HNO3 (6 mL) plus HF (2 mL). The results indicate that complexing acids are not required for the subsequent determination of Cd in all types of lipsticks evaluated. On the other hand, complexing acids were essential for ensuring quantitative results for Pb in shimmering lipstick. Thus, by using HNO3 combined with only 0.5 mL of HCl, it was possible to obtain quantitative results for Pb and Cd in lipsticks. Under these conditions, recoveries for Cd and Pb were between 95 and 103%. No statistical difference was observed between the results obtained using the proposed method (HNO3/HCl) and those obtained using HNO3/HF, where a complete dissolution of the lipsticks' inorganic fraction occurred. Moreover, by using HCl, HF was avoided and solutions more compatible with ICP-MS analysis were obtained. The limits of detection for Cd and Pb were 3 and 77 ng g−1, respectively. This method was applied for a variety of lipsticks, and the concentration of Cd and Pb ranged from ＜3 to 31 ng g−1 and 271 to 2250 ng g−1, respectively. [ABSTRACT FROM AUTHOR]