Using dilute acid and enzymes simultaneously to pre-treat lignocellulose is no problem if your concern is only ethanol or biofuel production but studying/isolating acid and heat tolerant fungi from the lake that may be able to degrade lignocellulose within the mud of the lake.is another matter. Toxic degradation products resulting from hydrolysis may be to harsh and can interfere with fermentation and enzyme activity of your target fungi.

Thank you Buenaflor for your response.

We have already isolated some fungi and can grow them at 40C (pH2.5) on media made of chopped pine needles.

I have edited my question for clarification.

Is the pH and temperature of your chopped pine needles medium (2.5) similar to its natural environment or you have adjusted them to simulate its natural environment? Adjusting it with H2SO4 MAY affect the enzyme activity of the fungi. Have you thought of getting water from its natural environment, sterilize them as diluent of your medium, This way you have the natural pH and some trace nutrients that maybe necessary for degradation of lignocellulose.

Thank you again Buenaflor for your response.

We already have the fungi growing on lignocellulose media but my goal now is to make a model of the environment from which we isolated the fungi; hence, my question regarding the specific conditions for a pretreatment analog.