The oyster mushroom, Pleurotus spp., is edible. About seventy species of Pleurotus spp. have been recorded. Many oyster mushrooms are primary decomposers of hardwood trees found worldwide. Thus, it can be cultivated on a wide variety of substrates containing lignin, cellulose and hemicellulose. It must obtain nutrients from such organic sources as dead organisms since they had absorbed nutrients after digesting large molecules into smaller units because of their secreted enzymes; thus, it has been grown in Iraq on various agro-wastes in the wild, or manually on cardboard, date palm wastes, and tree sawdust.
Since ancient times, macrofungi have been used as a valuable food source and as traditional medicines around the world. The fungi constitute an important source for some compounds including enzymes and antibiotics. Consequently, the antimicrobial activity of various polysaccharides from medicinal mushrooms is being reevaluated in relation to their clinical efficacy, given that such compounds would be expected to function to ward off bacterial and fungal infections resistant to current antibiotics. Medicinal mushrooms are able to synthesize a great amount of secondary metabolites that present anti-tumoral, antiviral, anti-inflammatory, antibacterial, antifungal and anti-yeast activities.
This study evaluated the antifungal activity of four fruiting bodies of oyster mushroom harvested from three agro-substrates in vitro.
Table of Contents
I. Introduction
II. Material and Methods
A. Strains
B. Media and Liquid Culture Filtrate Preparation
C. Bioactivity of Filtrate of Oyster Mushrooms Mycelium
D. Bioactivity of Mycelia of Oyster Mushrooms
E. Statistical Analysis
III. Results
A. Microbial Growth in Liquid Culture Filtrates of Pleurotus spp.
B. Interaction Between Mycelia of Pleurotus spp. and Colonies of Pathogenic Bacteria
IV. Discussion
V. Conclusion
Research Objectives and Focus
This study aims to investigate and evaluate the in vitro antimicrobial and anti-yeast activity of four oyster mushroom species (Pleurotus spp.) by testing both their mycelia and liquid culture filtrates against selected pathogenic strains.
- Antimicrobial efficacy of Pleurotus mycelia and filtrates
- Comparative analysis of four distinct oyster mushroom species
- Inhibition effects on Gram-positive and Gram-negative bacteria
- Evaluation of anti-yeast properties against Candida parapsilosis
- Influence of secondary metabolites and heat-stable compounds
Excerpt from the Publication
IV. DISCUSSION
Secondary metabolism in liquid medium was important against bacteria. Fig. 1 showed effect of Pleurotus spp. filtrate against growth of bacteria and yeast. The filtrate of P. salmoneostramineus was best one compared with other filtrates against Pseudomonas aeruginosa ATCC 27853 and Candida parapsilosis ATCC 22019 respectively. Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212 and Staphylococcus aureus HIP10267 have low sensitive due to the genetic characters of species of oyster mushroom which lead to different secondary metabolism. Metabolism affected on production bioactivity of this filtrate. Bioactivity of filtrate of P. salmoneostramineus may be belong to glycoprotein called Indolone was important for O2 production in water [15]. The chemical composition of liquid filtrate of oyster mushroom is varying according to type of product of fungi [16].
The filtrate of pink strain P. salmoneostramineus has a higher antimicrobial activity as to comparison other filtrates and PDB (Fig. 1). And also, P. cornucopiae liquid filtrate was appeared low growth of Gram-positive bacteria Staphylococcus aureus HIP10267, Enterococcus faecalis ATCC 29212 and Candida parapsilosis ATCC 22019 (Fig. 1). None of the filtrates of P. ostreatus (grey and white strains) showed any activity against pathogenic bacteria and yeast.
Resistant bacteria were appeared in liquid filtrate because of loss some secondary metabolism bioactivity such proteins and polysaccharides by heat when sterilized [17]. Oyster mushrooms enable to produce metabolism products in 48 h to inhibit growth of pathogenic bacteria [18] due to produce polysaccharides, proteins, enzymes and triterpenoides of mycelia of Pleurotus spp. [19, 5].
Summary of Chapters
I. Introduction: Discusses the nutritional and medicinal properties of oyster mushrooms and the growing interest in their secondary metabolites for clinical applications.
II. Material and Methods: Details the cultivation of the four oyster mushroom species and the specific laboratory protocols used to test their bioactivity against selected bacteria and yeast.
III. Results: Presents the recorded data regarding biomass weight, final pH values, and the calculated inhibition percentages of the mushrooms against pathogenic strains.
IV. Discussion: Analyzes the experimental findings in relation to existing literature, focusing on the role of secondary metabolites like indolone in antimicrobial activity.
V. Conclusion: Summarizes the key findings, identifying the pink strain P. salmoneostramineus as the most effective species for anti-bacterial and anti-yeast activity.
Keywords
Pleurotus spp., Antimicrobial activity, Culture filtrate, Mycelia, Oyster mushroom, Pathogenic bacteria, Candida parapsilosis, Secondary metabolites, Bioactivity, In vitro study, Indolone, Inhibition percentage.
Frequently Asked Questions
What is the primary focus of this research?
The research investigates the in vitro antimicrobial and anti-yeast potential of both the mycelia and liquid filtrates of four different oyster mushroom species (Pleurotus spp.).
What are the main thematic areas covered?
The study covers mushroom cultivation, the extraction of secondary metabolites, and the evaluation of their inhibitory effects on specific pathogenic bacterial and yeast strains.
What is the central research question?
The research seeks to determine whether various oyster mushroom species and their liquid filtrates possess significant inhibitory activity against common human pathogenic microbes.
Which scientific methods are employed?
The study utilizes in vitro bioactivity testing, including broth dilution for filtrates and dual culture methods for mycelia, followed by statistical ANOVA analysis to determine significance.
What topics are discussed in the main body?
The main body addresses the preparation of samples, the measurement of bacterial growth via optical density, inhibition zone analysis, and the influence of heat sterilization on secondary metabolites.
Which keywords define this work?
Key terms include Pleurotus spp., antimicrobial activity, culture filtrate, mycelia, pathogenic bacteria, and secondary metabolites.
Why did the researchers test P. salmoneostramineus?
It was included as one of four species to compare its potential secondary metabolite production against the more common grey and white strains of P. ostreatus.
What role does the substance "Indolone" play?
The authors suggest that the glycoprotein indolone, isolated from P. salmoneostramineus, may contribute to the observed antimicrobial bioactivity.
How does heat affect the antimicrobial properties of the filtrates?
The discussion notes that heat sterilization can lead to a loss of secondary metabolism bioactivity, such as proteins and polysaccharides, which reduces the inhibitory effect.
- Arbeit zitieren
- Sajid AL - Saeedi (Autor:in), Mustafa N. Owaid (Autor:in), Idham Abed Ali Al-Assaffii (Autor:in), 2016, Antifungal activity of cultivated oyster mushrooms on various agro-wastes, München, GRIN Verlag, https://www.grin.com/document/417172
