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In order to guarantee an adequate level of macromolecular reserves, and allow their successful transfer to the natural environment, we have studied the survival, growth and biochemical composition (carbohydrates, lipids and proteins) of the spat (initial length 3.77 ± 0.64 mm) of the mangrove oyster Crassostrea rhizophorae, fed with seven different combinations (diets) of three tropical microalgae: Chaetoceros sp. Araya strain (Ch-A), Isochrysis galbana (Ig) and Tetraselmis chui (Tc). The microalgae biochemical composition was also determined. In the indoor bioassay, each one of the seven diets was assigned three aquariums (replicates with 21 spat). In addition, three more replicates were arranged in an outdoor environment (control). After 36 days, the biochemical and biometric parameters of the juveniles in the indoor bioassay were determined, and they were transferred to the outdoor environment. The control treatment suffered considerably high mortality rates (≈80%) during this period and it was not possible to obtain further data from it for the experiment. The transferred juveniles continued to be cultured in suspension for 30 days, after which their biochemical and biometric parameters were evaluated again. During this period, samplings of the environmental variables were taken weekly. In general, within the indoor period, the greatest biometric and biochemical values were obtained in the organisms fed with one monoalgal diet (Ch-A), bialgal diets (Ch-A+Tc; Ch-A+Ig) and the trialgal diet (Ch-A+Ig+Tc), a tendency that remained in the outdoor environment. This was attributed to the balanced contribution of biomolecules previously offered by these diets. These results suggest that the juveniles made use of the energy content found in carbohydrates and lipids once they were transferred outdoors; where these energy sources were probably catabolized to compensate for the scarce availability of food (low chlorophyll a and organic seston) observed in the outdoor culture site. RESUMEN | Con el fin de garantizar un nivel adecuado de las macromoleculas energéticas, que permitan su transferencia exitosa al ambiente natural, se estudió la supervivencia, el crecimiento y la composición bioquímica (carbohidratos, lípidos y proteínas) de pre-semillas (“spat”) (talla inicial 3.77 ± 0.64 mm) de ostra de mangle Crassostrea rhizophorae, alimentada con tres microalgas tropicales: Chaetoceros sp. Cepa Araya (Ch-A), Isochrysis galbana (Ig) y Tetraselmis chui (Tc), ofertadas como dietas unialgales o mezcladas en dietas bialgales y trialgales. La composición bioquímica de las diferentes cepas de microalgas fue también determinada. En el bioensayo bajo condiciones de laboratorio (hatchery), se utilizaron tres acuarios (réplicas con 21 semillas) para cada una de las dietas. Adicionalmente tres réplicas se confinaron en el medio ambiente (control). Después de 36 días, se analizó sus contenidos bioquímicos y registraron las variables biométricas, y los juveniles se transfirieron al ambiente exterior (tres réplicas) y se cultivaron en suspensión durante 30 días. Al final del cultivo en el medioambiente se obtuvieron de nuevo sus variables bioquímicas y biométricas. Sin embargo, debido a una alta mortalidad ocurrida en lasréplicas de control (≈80%), no fue posible obtener más datos de estas últimas, después de 36 días. Durante el cultivo en el medio ambiente, se tomaron muestras semanales de las variables ambientales. En general, en el cultivo en el laboratorio, los mayores valores biométricos y bioquímicos se obtuvieron en los organismos alimentados con la dieta monoalgal (Ch-A), dietas bialgales (Ch-A + Tc y Ch-A + Ig) y la trialgal (Ch-A+Ig+Tc), una tendencia que se mantuvo en el cultivo en el medio ambiente. Lo anterior se atribuyó a la contribución equilibrada de las biomoléculas ofrecidas anteriormente por estas dietas. Estos resultados evidenciaron el uso de la energía contenida en carbohidratos y lípidos, por parte de las ostras juveniles, una vez que fueron transferidas al medio ambiente, donde estas fuentes de energía probablemente fueron catabolizadas para compensar la escasa disponibilidad de alimentos (baja Clorofila a y materia orgánica) observada en el sitio de cultivo en el medio ambiente.

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Abstract: Near-infrared spectroscopy (NIRS) is among the many tools available to study the biochemical diversity of coffee species. This technique is inexpensive, fast and accurate, and it requires only small amounts of samples. The aim of this study was to use NIRS to estimate the amount of diterpenes (cafestol and kahweol) in green coffee. To construct the prediction model, 126 Ethiopian accessions coffee collection and 44 modern cultivars were analyzed. The total sample set was split into two groups as follows: a group of 130 samples for calibration and a group of 40 samples for the validation step. Reference values of cafestol and kahweol were determined by high performance liquid chromatography (HPLC). Cafestol values ranged from 182.62g to 1308.62mg 100g−1, and kahweol values ranged from 182.69 to 1265.41mg 100g−1. To improve the quality of the calibration step, a pretreatment with the second derivative was applied to smooth the raw spectra. The prediction models of cafestol and kahweol were developed using the modified partial least squares regression (mPLS). The performance of these models was evaluated by the ratio of performance deviation (RPD) and R 2 parameters, obtained by the ratio of the NIR prediction data and the corresponding reference data. The prediction models of cafestol (RPD=2.74; R 2 =0.89) and kahweol (RPD=2.2; R 2 =0.88) confirm the validity of NIRS analysis to determine diterpenes contents in green coffee. [Copyright &y& Elsevier]