1.Downstream processing of mosquitocidal toxins from solid state fermentation of Lysinibacillus sphaericus and Bacillus thuringiensis israelensis
Magda Abd El-Ghaffar El-Bendary ; Maysa El- sayed Moharam ; Shimaa Ragab Hamed ; Sahar Saleh Mohamed
Malaysian Journal of Microbiology 2017;13(2):79-84
Aims: The aim of this study was downstream processing of moquitocidal toxins produced by Lysinibacillus sphaericus
(L. sphaericus) and Bacillus thuringiensis israelensis (Bti) under solid state fermentation.
Methodology and results: Two mosquitocidal strains (L. sphaericus and Bti) were grown separately in trays under solid
state fermentation for toxin production. The best conditions for extraction of crude toxins from fermented solids of both
cultures were tap water at 5-50 °C, for 10 min under static conditions. Also, concentrated mosquitocidal toxins were
efficiently extracted from fermented solids by 4 constitutive additions of 500 mL tap water to 1 kg of fermented culture at
room temperature (25 °C) for 5 min each under static conditions. Both extracted toxins were formulated with talcum
powder and they were stable for 8 months at room temperature.
Conclusion, significance and impact of study: It is very important to study the operating conditions for mosquitocidal
toxins extraction from solid state fermentation (SSF) and its formulation in cost effective manner.
2.The biological activities of anise and fennel essential oils against indoor opportunistic fungi
Shimaa Ragab Hamed ; Raed Saed Al-Wasify
Malaysian Journal of Microbiology 2023;19(no.5):535-544
Aims:
This study investigated the antifungal activities of essential oils (EOs) extracted from anise (Pimpinella anisum) and fennel (Foeniculum vulgare) against indoor opportunistic fungi (Penicillium frequentans, Aspergillus flavus, Aspergillus niger and Chaetomium globosum) isolated from an apartment wall surfaces. The antioxidant activity of extracted EOs was examined.
Methodology and results:
The components of EOs were identified and quantified using gas chromatography (GC-MS). Antifungal activity, minimum inhibitory concentration (MIC) and killing potential assays of EOs were performed. EOs extracted from anise and fennel showed considerable antifungal activities against the four indoor opportunistic fungi. EO from fennel showed high antifungal activity against A. niger and C. globosum, while EO from anise showed high antifungal activity against P. frequentans and A. flavus. EOs from anise and fennel showed the same MIC values (5-8 mg/mL). EOs from anise and fennel showed high killing potential after 72 h against the indoor opportunistic fungi. The highest killing potential was against P. frequentans and the lowest killing potential was against C. globosum. Moreover, EOs from anise and fennel showed high antioxidant activities with scavenging activity after 90 min of 89.39% and 90.2%, respectively.
Conclusion, significance and impact of study
EOs extracted from anise and fennel could be used as natural antifungal agents against indoor opportunistic fungi.