Esther Koplowitz, the Spanish environmental services businesswoman who is one of Europe’s most generous philanthropists, has donated €15 million to boost biomedical research through a new Barcelona-based center linked to some of Europe’s most prestigious research institutions. The donation by Ms. Koplowitz, the principal shareholder in the Spain-based company FCC, has been hailed as the largest private donation ever made by an individual in Europe in the field of scientific research.