Fungal waste biomass from biotechnology applications could be used to harvest microalgae for fuels and chemicals production
Waste biomass from fungal fermentation processes could be used to bind to and harvest microalgae being used in other biotechnology applications. A*STAR researchers have successfully demonstrated this procedure with fungal mycelium — the main vegetative part of a fungus such as the tangled mass of underground fibers beneath sprouting mushrooms.
Mixing a fungal culture with microalgae culture followed by aerated mixing can precipitate the algae bound to the fungal mycelium. This allows extraction of useful microalgae/fungal biomass for direct use or further purification of algal products. © 2015 A*STAR Institute of Chemical Engineering Sciences
Suitable fungal biomass might be obtained cheaply or perhaps even freely to offer a sustainable and environmentally sound method for harvesting microalgae. The potential uses of microalgae include burning their biomass as fuel or turning them into mini-factories for making biodiesel or specific chemicals including lipids, sugars or drugs.
"The lack of an economic and effective method for harvesting microalgae is one of the bottlenecks limiting their commercial use in biotechnology," explains Mahabubur Talukder of the A*STAR Institute of Chemical and Engineering Sciences.
Microalgae can be cultured in a broth and existing methods for harvesting them include centrifugation or a precipitation process called flocculation using chemical treatments. All current methods however suffer significant drawbacks, explains Talukder. For instance, centrifugation is too expensive to be used for low value uses of microalgae, such as biofuel. Similarly inadequate, chemical flocculation contaminates the harvested microalgae with toxic metal salts, causing difficulties in further processing or extraction of desired products.
The A*STAR team knew that less toxic natural materials such as starch could be used to precipitate and collect some freshwater microalgae, but this is not suitable for marine microalgae due to undesirable effects of the salty solutions.
What is needed is a non-toxic and preferably natural and widely available material that can bind to, immobilize and precipitate both freshwater and marine microalgae. This led the researchers to investigate fungal mycelium, which they found was not only effective but could also add value by contributing to the total biomass in the combined and harvested material.
The team screened several varieties of fungi with varying results, in some cases achieving a harvesting efficiency of 97 per cent after several hours of mechanical mixing with four times the mass of wet mycelium . Detailed analysis indicated that the key to the binding and immobilizing effect is a simple ionic attraction between the differing electric charges on the surface of the microalgae and the fungal mycelium.
"The next step is to find a collaborator or industrial partner willing to invest in and further explore the invention and commercialize it," says Talukder, as his focus turns from the laboratory toward the challenges of scale-up and industrial production.
 Talukder, M. R., Das, P. & Wu, J. C. Immobilization of microalgae on exogenous fungal mycelium: A promising separation method to harvest both marine and freshwater microalgae. Biochemical Engineering Journal 91, 53–57 (2014).
A*STAR Research | ResearchSEA
Single-stranded DNA and RNA origami go live
15.12.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
New antbird species discovered in Peru by LSU ornithologists
15.12.2017 | Louisiana State University
DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.
Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...
MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.
Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...
Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...
Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.
To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...
The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.
Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...
11.12.2017 | Event News
08.12.2017 | Event News
07.12.2017 | Event News
15.12.2017 | Power and Electrical Engineering
15.12.2017 | Materials Sciences
15.12.2017 | Life Sciences