Potential antibiotic-producing fungal strains isolated from pharmaceutical waste sludge

Sunday Osaizua Omeike,Adebayo Aliyu Lasisi,Sarafadeen Olateju Kareem

doi:10.1186/s43088-019-0026-8

Abstract

BackgroundAntibiotic resistance and dearth of novel compounds from natural sources warrants the need to search other environments for potential antibiotic-producing microbial species. The study investigated isolation and identification of antibiotic-producing fungi from pharmaceutical waste sludge.ResultsSeven hundred and ninety-seven isolates obtained from sludge of seven pharmaceutical industries in Sango Ota, Ogun State using several growth media, with mould isolates highest (696). Isolated species were from genera Aspergillus (28.55%), Penicillium (18.35%), Trichoderma (13.44%), Rhizopus (10.21%) and Geotrichum (4.01%), and Stachybotrys (0.13%). The CFS of strains named Geotrichum candidum OMON-1, Talaromyces pinophilus OKHAIN-12, and Penicillium citrinum PETER-OOA1 had high reproducible bioactivity against Staphylococcus aureus (32 ± 0.12 mm) and Klebsiella pneumoniae (29 ± 0.12 mm) while P. citrinum MASTER-RAA2 had activity against K. pneumoniae only. Active metabolites were successfully extracted using Diaion HP-20 and methanol:iso-propanol:acetone (6:3:1 v/v). Antibacterial-active fractions of fungal extract successfully eluted with 40–60% NaCl on ion-exchange chromatography using a cation column.ConclusionsThe study successfully screened antibiotic-producing fungal species from pharmaceutical waste storage facilities. Study also showed that similar species from same toxic environment could potentially produce different metabolites.

Highlights

Antibiotic resistance and dearth of novel compounds from natural sources warrants the need to search other environments for potential antibiotic-producing microbial species
1 Background Natural antibiotics are chemical substances derived from microorganisms, which destroy and/or inhibit the growth of other microorganisms [1]
Due to the constant need for antibiotics to cure infections and diseases, several antibiotics have been introduced for clinical use, from the discovery of penicillin to the various synthetically derived modifications presently in use

Summary

Introduction

Antibiotic resistance and dearth of novel compounds from natural sources warrants the need to search other environments for potential antibiotic-producing microbial species. Due to the constant need for antibiotics to cure infections and diseases, several antibiotics have been introduced for clinical use, from the discovery of penicillin to the various synthetically derived modifications presently in use. According to Hamburg’s Academy of Sciences and Humanities/German National Academy of Sciences [3], 73% of antibiotics approved between 1981 and 2005 were structural modification of compounds in five antibiotic classes, with only three novel classes introduced over the past 30 years [4, 5]. Coupled with increased antibiotic resistance, there is a need for a continuous search for novel antibiotics discovery

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Results