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Tomato skins and their mixtures with seeds were submitted to supercritical CO 2 extraction using a flow apparatus at pressures of 250 and 300 bar and temperatures of 60 and 80°C. Two different mean particle sizes (80 and 345 µm) were used at two solvent flow rates (0.792 and 1.35 kg/h). The yields of lipids, lycopene, and -carotene obtained by supercritical fluid extraction were compared with those obtained by conventional organic solvent extraction. Supercritical fluid extraction from tomato skins at 300 bar and 80°C allowed the recovery of 80% of the lycopene and 88% of the -carotene, using about 130 g of CO 2 per gram of matrix at the lower flow rate of CO 2 .

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The aim of this study was to investigate the biomechanical behaviour of maxillary premolar teeth regarding root morphology and abfraction depth, submitted to axial and oblique occlusal load. The investigation was conducted using 3D finite element analysis and strain gauge test. Sound maxillary premolar single and double root were selected for 3D model generation. The teeth were scanned for external morphology data acquisition. The 3D geometry was stored in *.STL and exported to Bio-CAD software (Rhinoceros-3D) to model generation. Mesh generation, mechanical properties and boundary conditions were performed in finite element software (Femap, Noran Engineering, USA). Twelve models were generated: sound tooth, 1.25 and 2.5 mm abfraction teeth. 100N compressive static load was applied: axially and 45° angle to the long axis on the palatine surface of the buccal cusp. Two strain gauges were bonded on the teeth mounted in a mechanical testing machine. Von Mises criterion showed that the double-root teeth associated with 2.5 mm abfraction and oblique loading presented higher stress values. Axial loading associated with single-root teeth propitiated the lowest stress rates. Double root sound 1.25 and 2.5 mm abfraction teeth associated with oblique loading showed the highest strain values (μS): 692.6, 1043.31 and 1236.14, respectively. Single root sound 1.25 and 2.5 mm abfraction teeth associated with oblique loading showed 467.10, 401.51 and 420.98 strain values, respectively. Axial loading showed lower strain rates, ranging from 136.12 to 366.91. The association of deep lesions, oblique loading and double-root tooth promoted higher stress and strain concentration.

Supercritical fluid extraction (SFE) with CO 2 of the volatile oil from fennel (Foeniculum vulgare ssp. piperitum (Ucria) Coutinho) was carried out at temperatures of 40 and 50°C and pressures of 90 and 100 bar in a flow apparatus using a two-stage fractional separation technique. The best conditions for extraction (pressure P = 90 bar, and temperature, T = 40°C) and separation (P = 80 bar, T = −10°C for the first separator and P = 20 bar, T = −10°C for the second) were used to assess the effect of different mean particle size and flow rate of CO 2 . The yield of the extraction and composition of the volatile oil were compared with those obtained by hydrodistillation. The study showed that the particle size of the fruits does not practically affect either the yield or the composition of the oil, with the exception of the presence of a small amount of waxes in the volatile oil extracted by SFE from the fruits presenting the highest particle size. Further, increasing of the flow rate of CO 2 does not seem to influence the composition, although it increases the rate of extraction, thus leading to a decrease of the extraction time. The fennel oil was analysed by gas chromatography (GC) and chromatography-mass spectrometry (GC-MS). The main compounds identified in the oils were fenchone (17%), estragol (21%) and (E)-anethole (43%).

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