Antimicrobial potential of boron-containing compounds: Antibacterial, antifungal, and antimycobacterial activities

Abstract

The global rise in multidrug-resistant (MDR) pathogens necessitates the discovery of new antimicrobial agents. Boron-containing compounds (BCCs) are increasingly studied for their broad-spectrum biological activities. The current study aimed to investigate the antibacterial, antifungal, and antimycobacterial activities of four different BCCs (Zinc borate, boric acid, borax, and Etidot-67) by determining their minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentrations (MBC/MFC). For the first time, the antimycobacterial activity of BCCs was evaluated against both reference and clinical strains. All tested compounds exhibited notable antimicrobial activity. Among them, boric acid and zinc borate showed strong antibacterial effects, particularly against Staphylococcus aureus and Salmonella typhimurium at 64 μg/mL. Borax displayed the most potent antimycobacterial activity, with a MIC of 64 μg/mL against Mycobacterium tuberculosis H37Ra (MT-H37Ra). Antifungal tests revealed boric acid to be highly effective against Candida albicans and Saccharomyces cerevisiae, with MIC values as low as 8-16 μg/ mL. These findings suggest that BCCs, especially borax and boric acid, may serve as viable candidates for the development of alternative antimicrobial therapies. However, further in vivo studies, toxicological assessments, and mechanistic investigations are necessary to support their clinical application.

Keywords

• Antibacterial activity
• Antifungal activity
• Antimycobacterial activity
• Boron-containing compounds
• Minimum Inhibition Concentration

Bor içeren bileşiklerin antimikrobiyal potansiyeli: Antibakteriyel, antifungal ve antimikobakteriyel aktiviteler

Abstract

Çoklu ilaca dirençli (MDR) patojenlerdeki küresel artış, yeni antimikrobiyal ajanların keşfini zorunlu kılmaktadır. Bor içeren bileşikler (BİB'ler), geniş spektrumlu biyolojik aktiviteleri nedeniyle giderek daha fazla araştırılmaktadır. Bu çalışma, dört farklı BİB'in (Çinko borat, borik asit, boraks ve Etidot-67) minimum inhibitör konsantrasyonlarını (MİK) ve minimum bakterisidal/fungisidal konsantrasyonlarını (MBK/MFK) belirleyerek antibakteriyel, antifungal ve antimikobakteriyel aktivitelerini araştırmayı amaçlamaktadır. BİB'lerin antimikobakteriyel aktivitesi ilk kez hem referans hem de klinik suşlara karşı değerlendirilmiştir. Test edilen tüm bileşikler anlamlı antimikrobiyal aktivite göstermiştir. Bunlar arasında borik asit ve çinko borat, özellikle 64 μg/mL'de Staphylococcus aureus ve Salmonella typhimurium'a karşı güçlü antibakteriyel etkiler göstermiştir. Boraks, Mycobacterium tuberculosis H37Ra'ya (MT-H37Ra) karşı 64 μg/mL'lik bir MİK ile en güçlü antimikobakteriyel aktiviteyi göstermiştir. Antifungal testler, borik asidin Candida albicans ve Saccharomyces cerevisiae'ye karşı oldukça etkili olduğunu ve MİK değerlerinin 8-16 μg/mL kadar düşük olduğunu göstermiştir. Bu bulgular, özellikle boraks ve borik asit olmak üzere BİB'lerin alternatif antimikrobiyal tedavilerin geliştirilmesi için uygun adaylar olabileceğini düşündürmektedir. Ancak, klinik uygulamalarını desteklemek için daha fazla in vivo çalışma, toksikolojik değerlendirme ve mekanik incelemeye ihtiyaç vardır.

Keywords

• antibakteriyal aktivite
• antifungal aktivite
• antimikobakteriyal aktivite
• bor içeren bileşikler
• minimum inhibisyon konsantrasyonu

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