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Study of the inhibition effect of yoghurt starter on Staph. aureus bacteria

دراسة الأثر التثبيطي لبكتريا بادئ اليوغورت (اللبن الرائب) في نمو بكتيريا Staph. aureus

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 Publication date 2010
  fields Food Sciences
and research's language is العربية
 Created by Shamra Editor




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This investigation was done in the laboratories of the Faculty of Agriculture – Damascus University in the Department of Food Sciences. The aim of this research use to study the inhibition effect of the growth and activity of Lactic acid bacteria used as starter and on the growth of Staph. aureus bacteria. Pure strains of Staph. aureus and Lactic acid bacteria was used the effect of Lactic acid bacteria (Streptococcus thermophilus and Lactobacillus bulgaricus) on the number of Staph. aureus was studied at 37 ◦C and 4◦C. The Lactic acid bacteria were inoculeted in milk for the manufacturing of yoghurt. The number of Staph. aureus was fixed then was decreased gradually according to time. And the decreasing number of this bacteria was clear when S. thermophilus and Lb. bulgaricus were used as a mixture starter, then when was used as a single starter, Lb. bulgaricus and S. thermophilus.


Artificial intelligence review:
Research summary
تهدف هذه الدراسة التي أجريت في مختبرات كلية الزراعة بجامعة دمشق إلى دراسة تأثير بكتيريا حمض اللاكتيك المستخدمة في صناعة اللبن على نمو بكتيريا المكورات العنقودية الذهبية (Staphylococcus aureus). تم استخدام سلالات نقية من بكتيريا المكورات العنقودية الذهبية وبكتيريا حمض اللاكتيك (Streptococcus thermophilus وLactobacillus bulgaricus) لدراسة تأثيرها على عدد بكتيريا المكورات العنقودية الذهبية عند درجات حرارة 37 درجة مئوية و4 درجات مئوية. تم تلقيح بكتيريا حمض اللاكتيك في الحليب لصناعة اللبن، ولوحظ أن عدد بكتيريا المكورات العنقودية الذهبية بدأ في الانخفاض تدريجياً مع مرور الوقت. كان الانخفاض في عدد هذه البكتيريا أكثر وضوحاً عند استخدام مزيج من S. thermophilus وLb. bulgaricus كمُبدئ مقارنة باستخدام كل نوع منهما بشكل منفرد.
Critical review
دراسة نقدية: تعتبر هذه الدراسة مهمة لأنها تسلط الضوء على تأثير بكتيريا حمض اللاكتيك على بكتيريا المكورات العنقودية الذهبية، مما يمكن أن يكون له تطبيقات مهمة في صناعة الأغذية وسلامتها. ومع ذلك، يمكن تحسين الدراسة من خلال تضمين مزيد من التفاصيل حول الظروف التجريبية مثل تركيز البكتيريا ومدة التعرض. كما أن الدراسة تفتقر إلى تحليل إحصائي متعمق يمكن أن يعزز من موثوقية النتائج. بالإضافة إلى ذلك، يمكن أن تكون هناك حاجة لمزيد من الدراسات الميدانية لتأكيد النتائج في ظروف واقعية.
Questions related to the research
  1. ما هو الهدف الرئيسي من هذه الدراسة؟

    الهدف الرئيسي هو دراسة تأثير بكتيريا حمض اللاكتيك المستخدمة في صناعة اللبن على نمو بكتيريا المكورات العنقودية الذهبية.

  2. ما هي أنواع بكتيريا حمض اللاكتيك التي تم استخدامها في الدراسة؟

    تم استخدام بكتيريا Streptococcus thermophilus وLactobacillus bulgaricus.

  3. ما هي درجات الحرارة التي تم اختبار تأثير بكتيريا حمض اللاكتيك عندها؟

    تم اختبار تأثير بكتيريا حمض اللاكتيك عند درجات حرارة 37 درجة مئوية و4 درجات مئوية.

  4. ما هو التأثير الملحوظ لبكتيريا حمض اللاكتيك على بكتيريا المكورات العنقودية الذهبية؟

    لوحظ أن عدد بكتيريا المكورات العنقودية الذهبية بدأ في الانخفاض تدريجياً مع مرور الوقت، وكان الانخفاض أكثر وضوحاً عند استخدام مزيج من S. thermophilus وLb. bulgaricus كمُبدئ.


References used
Abdelnoor, A. M., Batshoun R., and Roumani B. M. (1983). "The bacterial flora of fruits and vegetables in Lebanon and the effect of washing on the bacterial content" Zentralbl. Bakteriol. Mikrobiol. Hyg. 177 :342–349
Alexandre, D. P., Silva M. R. Souza M. R. (2002). “Antimicrobial activity of lactic acid bacteria from artisonal minas cheese against indication microorganisms” Arquivo brasilerio de medicina veterinaria 54: 424 – 428
Ash, M. (1997). "Staphylococcus aureus and Staphylococcal Enterotoxins. In: Foodborne microorganisms of the public health importance, 5 Edition", (Eds) Hocking, A.D., Arnold, G., Jenson, I., Newton, K. and Sutherland, P. AIFST (NSW Branch), Sydney, Australia. 313-332
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