, 2009, Kurzrock and Speer, 2001 and Scharnhop and Winterhalter, 2009). The mass errors were lower than 5 ppm confirming the molecular formulas. The results obtained in tandem mass spectrometry

studies of m/z 195, 315 and 317 corroborate with the assigned structures in accordance with literature data: caffeine ( Alonso-Salces et al., 2009) (Elab 25 eV: 195 → 138, 110), cafestol ( Scharnhop & Winterhalter, 2009) (Elab 18 eV: 317 → 299, 281, 147, 133) and kahweol ( Scharnhop & Winterhalter, 2009) (Elab 18 eV: 315 → 297, 279, 149, 131). The conditions clearly improve cafestol and kahweol concentrations; methylated fatty acids can be seen at the end of chromatogram in Fig. 3(B), due to methanolysis. Furthermore, the literature highlights the need for anhydrous methanol, which microwave heating showed to be unnecessary, greatly simplifying the methodology and costs ( Bertholet, Selleck Volasertib 1987). Quantification of cafestol and kahweol was accomplished with the external standard method as response factor for the HPLC, obtained by linear regression of known concentrations versus peak area. Linearity was observed for a concentration range of 1–56 μg/mL, with a 5% confidence level and a r correlation coefficient for cafestol and

kahweol higher than 0.99. Coefficients of variation (CV) below 7% were observed for the mixture of free diterpenes. A fast and improved method to obtain a mixture of cafestol (1) and kahweol (2) from green Arabica coffee oil was successfully developed. The microwave-assisted protocol proved to be simple, selleck kinase inhibitor fast, enabled the use of higher reaction amounts and can be carried out at higher temperatures. The rapid

speed of reaction avoided the development of undesired products and increased product yield. In addition, the microwave-assisted method required no clean-up procedure when compared to conventional heating. We thank the Brazilian science foundations FAPERJ, CAPES, CNPq and EMBRAPA CAFÉ for financial assistance. The authors also wish to thank Grão Mestre Café for providing the green coffees. We are grateful to Prof. Paula F. de Aguiar for helping with statistics, Prof. Alberto J. Cavalheiro for the support on HPLC. “
“The edible mushroom Pleurotus ostreatus has a pleasant taste and nutritional properties that are beneficial to health. Daily intake of this mushroom may influence the lipid profile in hypercholesteraemic Teicoplanin patients and improves antioxidant status ( Hossain et al., 2003 and Jayakumar et al., 2007). This mushroom can also be a source of elements, such as iron (Fe), zinc (Zn), selenium (Se), copper (Cu) and molybdenum (Mo), which are involved in many essential biochemical processes ( Zaidman, Yassin, Mahajna, & Wasser, 2005). The bioaccumulation potential of nutrients by fungi enriched with essential elements for human health has been investigated in mycelium and also in mushroom (Munoz et al., 2006, Rabinovich et al., 2007, Silva et al., 2010 and Silva et al., 2012).

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