Antibacterial Effects of Silver Nanoparticle-doped “Black Physician: Tar”

Abstract

Aim: This study evaluated the antibacterial activity of silver nanoparticles (AgNPs) synthesized using Juglans regia (walnut) leaf extract and coated with Cedrus libani tar against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria.
Method: AgNPs were biosynthesized using walnut leaf extract as the reducing agent and subsequently coated with cedar tar. The antibacterial activities of the individual components (walnut extract and tar), uncoated AgNPs, and tar-coated AgNPs were assessed via standard disc diffusion assays and compared with conventional antibiotics.
Results: Both walnut extract and tar exhibited inherent antibacterial properties, though they were less effective than standard antibiotics. AgNPs synthesized with walnut extract showed enhanced antibacterial activity; incorporation of tar further improved performance, yielding inhibition zones comparable to those produced by antibiotics against both bacterial strains.
Conclusion: Tar coating synergistically enhanced the antibacterial efficacy of biosynthesized AgNPs without requiring higher nanoparticle concentrations. Tar-coated AgNPs synthesized using walnut leaf extract may therefore serve as promising alternative antibacterial agents.

Keywords

• Silver nanoparticles
• walnut leaf extract
• cedar tar
• antibacterial activity
• biosynthesis

Gümüş Nanopartikül Katkılı “Siyah Hekim: Katran”ın Antibakteriyel Etkileri

Abstract

Amaç: Bu çalışmada, Juglans regia (ceviz) yaprağı ekstresi kullanılarak sentezlenen ve Cedrus libani katranı ile kaplanan gümüş nanopartiküllerin (AgNP'ler) Gram-pozitif (Staphylococcus aureus) ve Gram-negatif (Escherichia coli) bakterilere karşı antibakteriyel aktiviteleri değerlendirildi.
Yöntem: Gümüş nanopartiküller, indirgeme ajanı olarak ceviz yaprağı ekstresi kullanılarak biyosentezlendi ve ardından sedir katranı ile kaplandı. Bireysel bileşenlerin (ceviz ekstresi ve katran), kaplanmamış AgNP'lerin ve katran kaplı AgNP'lerin antibakteriyel aktiviteleri standart disk difüzyon yöntemleriyle değerlendirildi ve konvansiyonel antibiyotiklerle karşılaştırıldı.
Bulgular: Hem ceviz ekstresi hem de katran, antibakteriyel özellikler gösterdi, ancak standart antibiyotiklere göre daha az etkiliydi. Ceviz ekstresi ile sentezlenen AgNP'ler artırılmış antibakteriyel aktivite sergiledi; ancak, katranın dahil edilmesi, her iki bakteri suşuna karşı antibiyotiklere benzer inhibisyon zonları ile antimikrobiyal performansı önemli ölçüde artırdı.
Sonuç: Katran kaplamasının AgNP'ler üzerindeki sinerjik etkisi, daha yüksek nanoparçacık konsantrasyonlarına gerek kalmadan antibakteriyel etkinliği artırdı ve ceviz yaprağı ekstresi kullanılarak sentezlenen katran kaplı AgNP'lerin, alternatif antibakteriyel ajanlar olarak umut verici olabileceğini göstermektedir.

Keywords

• Gümüş nanopartiküller
• ceviz yaprağı ekstresi
• sedir katranı
• antibakteriyel aktivite
• biyosentez

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