OPTIMIZATION OF IN-VITRO BIOFILM FORMATION IN STRAINS OF STREPTOCOCCUS MUTANS AND STAPHYLOCOCCUS EPIDERMIDIS IN DIFFERENT GROWTH CONDITIONS

Abstract

Objective: Microorganisms reside in polymer-coated communities known as biofilms, which represent a major virulence factor by conferring resistance to treatment in associated infections. Biofilms are therefore a frequent subject of health-related research. However, standard laboratory strains have been cultured under inconsistent conditions, with limited data available on optimal biofilm production parameters. This study aimed to determine the optimal in vitro biofilm formation conditions for Streptococcus mutans ATCC 25175 and Staphylococcus epidermidis ATCC 35984 by systematically evaluating growth media, sugar types/concentrations, atmospheric conditions, and incubation periods.

Material and Method: S. mutans and S. epidermidis strains were cultured under various conditions, including media (Brain Heart Infusion and Mueller Hinton Broth), sugar types/concentrations (sucrose and glucose), atmospheres (aerobic vs. 5% CO₂), and incubation times (24 and 48 hours). Biofilm production was quantified by standard crystal violet staining in microtiter plates.

Result and Discussion: Highest biofilm production for S. mutans occurred in BHI with 2% sucrose, under 5% CO₂, after 24-48 hours. For S. epidermidis, peak biofilm was in MHB with 1% glucose, under aerobic conditions, after 24 hours. These findings highlight the need for species-specific optimization of biofilm-inducing conditions when using standard strains.

Keywords

• Biofilm
• glucose
• Staphylococcus epidermidis
• Streptococcus mutans
• sucrose

STREPTOCOCCUS MUTANS VE STAPHYLOCOCCUS EPİDERMİDİS SUŞLARINDA FARKLI BÜYÜME KOŞULLARINDA İN-VİTRO BİYOFİLM OLUŞUMUNUN OPTİMİZASYONU

Abstract

Amaç: Mikroorganizmalar, polimer kaplı topluluklar olan biyofilmler içinde yaşarlar. Biyofilm, önemli bir virülans faktörü olup neden olduğu enfeksiyonların tedavisi güçtür ve birçok sağlık çalışmasının konusudur. Ancak, bu çalışmalarda kullanılan standart suşların optimum biyofilm üretim koşulları yeterince bilinmemektedir. Bu çalışma, Streptococcus mutans ATCC 25175 ve Staphylococcus epidermidis ATCC 35984 suşlarının optimum biyofilm üretim koşullarını; farklı büyüme ortamları, şeker konsantrasyonları, atmosferik koşullar ve inkübasyon süreleri açısından araştırmayı amaçlamaktadır.

Gereç ve Yöntem: S. mutans ve S. epidermidis suşları, farklı kültür ortamları (Brain Heart Infusion – BHI ve Mueller Hinton Broth – MHB), şeker türleri/konsantrasyonları (sükroz ve glukoz), atmosferik koşullar (aerobik ve %5 CO₂) ile inkübasyon süreleri (24 ve 48 saat)’nde in vitro koşullarda kültüre edilerek, biofilm üretimi mikrotiter plakalarda standart kristal viyole boyama yöntemiyle kantitatif olarak ölçülmüştür.

Sonuç ve Tartışma: Elde edilen bulgulara göre; S. mutans’ın en yüksek biyofilm üretimi, %2 sükroz ilaveli BHI ortamında, %5 CO₂ atmosferinde ve 24–48 saat inkübasyonda gözlenmiştir. S. epidermidis için ise en yüksek biyofilm üretimi, %1 glukoz içeren MHB ortamında, aerobik koşullarda ve 24 saat inkübasyonda tespit edilmiştir. Bu bulgular, özellikle standart laboratuvar suşlarının kullanıldığı sağlık odaklı araştırmalarda, biyofilm indükleyici koşulların türe özgü optimizasyonunun önemini ortaya koymaktadır.

Keywords

• Biyofilm
• glukoz
• Staphylococcus epidermidis
• Streptococcus mutans
• sükroz

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