COMMERCE, Calif. — Bodega Latina Corp. here, operators of nine El Super supermarkets, said yesterday it has signed a definitive agreement to purchase the seven Southern California stores operated by Gigante USA. Terms of the transaction were not disclosed; the deal is expected to close in late August. Bodega Latina said it will convert the stores to the El Super banner. Mexico City-based Grupo Gigante, the parent company of Gigante USA, was sold earlier this year to Organizacion Soriana, Monterrey, Mexico, which implied at the time it would operate them. However, Bodega Latina said the agreement to purchase Gigante USA was "facilitated by an agreement" between Grupo Gigante Mexico and Soriana. The Gigante USA stores are located in Arleta, Anaheim, Compton, Covina, Inglewood, Santa Fe Srings and Los Angeles, and range in size from 45,000 to 77,000 square feet. El Super operates eight ethnic-oriented supermarkets in Southern California and one in Phoenix, whose sizes range from 40,000 to 48,000 square feet.  According to Carlos Smith, president and chief executive officer of Bodega Latina, "We believe that bringing the Gigante stores into the El Super family will provide synergies that will benefit both the company and consumers in Southern California."