A novel series of antibiotics designated the XK-88 series are produced by culturing a microorganism belonging to the genus Streptomyces in a nutrient medium and thereafter recovering the antibiotics from the culture liquor.BACKGROUND OF THE INVENTIONThe present invention relatees to novel antibiotics and a process for the production thereof. More specifically the present invention relates to novel antibiotics designated, XK-88-1, XK-88-2, XK-88-3 and XK-88-5 and a process for producing such antibiotics.Antibiotics which exhibit activity against a borad spectrum of bacteria are always in demand. To this end, a new species of microorganism has been isolated from soil located in Tajima-cho, Hofu-shi, Yamaguchi-ken, Japan. This new species, when cultured, produces a series of new antibiotics, the XK-88 series, all of which exhibit strong antibacterial activity against various Gram-positive and Gram-negative bacteria. Accordingly, the antibiotics of the invention are useful to clean and sterilize laboratory glassware ans surgical instruments, and may also be used in combination with various soaps for sanitation purposes as in cleaning and sanitizing hospital rooms and areas used for the preparation of food.