Histological Procedures Carried out During Coconut Somatic Embryogenesis.

Histological methods allow to characterize the developmental changes that occur in plant tissues during in vitro culturing of explants. Different procedures to assess these changes have been reported in the literature. Here we describe a simple histological procedure to evaluate the development of explants using the fixation with paraformaldehyde, embedding with methacrylate resin and staining with periodic acid Schiff's reagent and naphthol blue black. This method allows to obtain high contrast in the stained cells, for a better characterization of cellular events that occur during coconut somatic embryogenesis.

Cocoa bean husk: industrial source of antioxidant phenolic extract.

BACKGROUND: Cocoa bean husk (CBH) is the principal by-product of the cocoa industry and a significant agro-industrial residue. In this study, using different hydrothermal treatments of CBH, it is shown that CBH is an important source of bioactive compounds, including theobromine, epicatechin and catechin. RESULTS: Treatment over 150 °C significantly increased the yield of total and individual phenols and theobromine as well as the antioxidant capacity of the liquid fraction. A total of 52 different genotypes of CBH harvested in two seasons of production were analyzed. Overall, higher amounts of total phenols, theobromine and epigallocatechin were detected in samples from the 2015 season, while samples from 2014 had higher quantities of catechin and similar quantities of epicatechin. CONCLUSION: CBH treatment at 170 °C for 30 min produces an antioxidant-rich extract high in phenols (55 mg g-1 ), sugars (220 mg g-1 ) and theobromine (56 mg g-1 ) that is suitable for applications in the food, cosmetic and nutraceutical industries. © 2018 Society of Chemical Industry.