A United States bankruptcy court approved the sale of the parent company of the Boston Store to a group of liquidators Wednesday — an action that could spell the end of two stores in Madison and affect hundreds of people who work in Bon-Ton Stores’ Milwaukee headquarters. The sale was approved after liquidators were the only bidders for Bon-Ton Stores during an auction in bankruptcy court Monday. “The company is committed to working constructively with the winning bidder to ensure an orderly wind-down of operations that minimizes the impact on associates, customers, vendors and the communities we serve,” Bon-Ton, which owns Boston Stores, Younkers and other department stores, said in a statement Wednesday. A joint venture of holders of the company’s second lien secured notes due 2021 and Great American Group and Tiger Capital Group will acquire Bon-Ton’s inventory and “certain other assets,” the statement said. Bon-Ton, which also has a headquarters in York, Pennsylvania, operates 250 stores across the United States, also including Bon-Ton, Bergner’s, Carson’s, Elder-Beerman and Herberger’s. Across Wisconsin, the company owns 13 stores, including Boston Store locations at the East Towne and West Towne malls, as well as one in Janesville, and employs more than 700 people at its Milwaukee headquarters. Online and mobile platforms will remain operating throughout the closing of the department stores.