Çeşitli süt işletmelerinden sağlanan çiğ süt, pastörize süt ve beyaz peynir örneklerinden 73 Staphylococcus izole edilmiştir. Bu bak¬terilerin 59'u (%80.82) S. aureus, 7'si (%9.59) S. epidermis ve 7'si (%9.59) de S.saprophyticus'dur. Bu bakterilerin lodometrik Test ve Kromo-jenik Sefalosporin Test yöntemleriyle beta-laktamaz enzim aktiviteleri tespit edilmiştir. Bu yöntemlere ilave olarak kontrol amacıyla penisilin-G antibiyotiği ile test edilmişlerdir. 73 Staphylococcusp'un 48'i (%65,75) beta-laktamaz pozitif, 25'i (%34,25) beta-laktamaz negatiftir. 48 betalaktamaz pozitif Staphylococcus'ların 46'sı S.aureus 2'si de S. epidermidir. 46 beta-laktamaz pozitif S. aureus/un 8'i (%17.39) çiğ sütten, 7'si (%15.22) pastörize sütten ve 31'i (%67,39) beyaz peynir örneklerinden izole edilmiştir. 2 betalaktamaz pozitif S. epidermidis/in 1'i (%50) çiğ sütten, 1'i (%50) beyaz peynirden izole edilmiştir. 48 beta-laktamaz pozitif Staphylococcus klavulanat-amoksisilin, amikasin, sefazolin, gentamisin, klindamisin ve ofloksasin antibiyotikleriyle test edilmişlerdir. 46 beta-laktamaz pozitif S.aureus'yın 43'ü (%93) klindamisin'e en yüksek oranda dirençli bulunurken 23 (%50) S. aureus de klavulanat-amoksisilin'e dirençli tespit edilmiştir. Beta-laktamaz pozitif 2 (%100) S. epidermidis klindamisin'e, gentamisin'e ve sefazolin'e en yüksek oranda dirençli bulunmuştur. Ofloksasin ve klavulanat-amoksisilin'e %50 oranında dirençli bulunmuşlardır.

73 Staphylococcus were isolated from raw milk, pasteurized milk and white cheese samples provided from several milk establishment. Of them; 59 were characterized as Slaureus (80.82%), 7 were S.epidermidis (9.59%) and 7 were S.saprophyticus (9.59 %). The beta-lactamase enzyme activity of these bacteria were also tested by iodometric test and chromogenic cephalosporin test medhods. In addition to these methods; with the aim of control it was tested with penicillin G. ob. Among 73 Staphylococcus; 48 were (65,75%) were beta-lactamase positive, 25 were (34,25%) found as betalactamase negative. Of 48 positive beta-lactamase Staphylococcus; only 2 were characterized as S.epidermidis while 46 were, S. aureus. The 8 (17,39%) of 46 beta-lactamase positive S. aureus were isolated from raw milk, while 7(15,22%) of 46 were isolated from pasteurized milk and 31(67,39%) were from white cheese samples. The one of 2 beta-lactamase was isolated from raw milk while the other one was isolated from white cheese. 48 beta-lactamase positive Staphylococcus were tested with the antibiotics of amoxicillin-clavulanic acid, amikacin, gentamicin, clindamycin and ofloxacin. While, 43 (93%) of 46 beta-lactamase positive S.aureus were found to show most resistance against clindamycin; 23(50%) S.aureus was also found to be resistant against amoxicillin-clavulanic acid. 2 (100%) S. epidermidis which were beta-lactamase positive were also found to be resistant with a ratio of 50% against ofloxacin and amoxicillin-clavulanic acid.