& Key message Non-structural carbohydrates (NSC) are the main form of carbon storage in broadleaved trees; precise NSC quantification is relevant to predict forest resilience. Sample microwaving before drying is considered to reduce NSC losses; however, evidence is scarce. We demonstrate that microwaving leaf and branch sapwood samples before drying did not significantly reduce NSC losses with respect to freezing or direct stove-drying. & Context Non-structural carbohydrates (NSC) mediate tree survival, but precise determinations of NSC concentrations remain challenging. An unclear aspect is whether carbohydrate losses during sample processing can be reduced by different sample treatments. & Aims We postulated that due to higher metabolic rates, leaves should be more responsive to sample treatments than branch sapwood, and resource-acquisitive species should be more responsive to sample treatment than resource-conservative species. & Methods In leaves and branch sapwood of six tree species, we compared the effects of three sample treatments on the concentrations of NSC, starch, and low-molecular weight sugars: sample microwaving before drying (microwave), sample freezing at − 20°C before drying (freezing), and only drying (stove). & Results We found that across species and tissues, freezing led to significantly higher NSC and sugar concentrations than microwave and stove. This effect was, however, entirely driven by the leaves. Although the effect of sample treatments on NSC, starch, and sugar concentrations differed among species, resource-acquisitive species were not necessarily more affected by sample treatments than resource-conservative species. & Conclusion Results suggest that either freezing or microwaving does not reduce carbohydrate losses in branch sapwood during sample handling and processing; however, freezing reduces leaf sugar and NSC losses when compared with microwave or direct stove-drying (194 words).

Growth inhibition of Candida utilis NRRL Y-660 took place in molasses stored at 60 "C for 120 days. The specific growth rate (JL,,,~~) was reduced from 0.42 h-' to 0.200 h-' as a result of a lack of affinity from the microorganism to the substrate and the increasing maintenance necessities. The K, values arose from 1.40 mg/ml to 4.28 mg/ml within the whole experiment. At the same time, the maintenance coefficient (m) increased from 0.250 to 3.80 mg/ml. In a continuous culture the "wash-out" conditions were reached at dilution rate values (D) close to 0.40 h-'. The process productivity decreased up to 15% from its original value in fresh molasses.

El objetivo del estudio fue evaluar el efecto de dietas con alta concentración de Saccharomyces cerevisiae sobre la proliferación de hemocitos en camarones Cryphiops caementarius machos. Los camarones (5.3 ± 1.2 cm de longitud total y 7.4 ± 2.9 g de peso total) se colectaron del río Pativilca (Perú). Cada camarón se mantuvo en un recipiente instalado dentro del acuario (seis camarones por acuario). Se empleó una dieta control (3% de levadura) y tres dietas experimentales (6, 9 y 12% de levadura) con dos repeticiones por tratamiento durante 28 días de cultivo. El número total de hemocitos fue mayor (p<0.05) con 6% de levadura (134.75 x 105 cél/ml), así mismo el número de granulocitos (31.44 x 105 cél/ml) y semigranulocitos (102.44 x 105 cél/ml). El número de hialinocitos disminuyó en todos los tratamientos y se mantuvo entre 0.31 y 1.56 x 105 cél/ml. El número de hemocitos atípicos se mantuvieron bajos en todos los tratamientos y sin diferencias con el basal (0.31 x 105 cél/ml). La dieta con 6% de levadura incrementó (p<0.05) el número total de hemocitos y los hemocitos granulocitos y semigranulocitos en los camarones machos C. caementarius. En cambio, las dietas con 9 y 12% de levadura afectaron (p<0.05) la proliferación de hemocitos totales y diferenciales.

Magnesium and potassium ions are present in sugar cane molasses in a concentration of about 0.3% and 2.5%, respectively, which is high enough to support biomass production from Candida utilis. Culture broth with 40 g/l of total reducing substances supplemented by the addition of 1 ppm of Mg2+ leads to a higher yield ( Y x / s ) in batch fermentation experiments. The subsequent addition of Mg2+ up to 10ppm decreases the yield coeficient from 0.53 to 0.42 without affecting the growth rate.Fermentation media supplemented with 1 to 10 ppm of K + decreased both the yield coeficient and the specific growth rate. A Mg/K ratio of about 0.1 seems to be optimal for yeast biomass propagation.