Every Wednesday, a grand transformation takes place in the reading room at Amrita School of Biotechnology. The neatly arranged desks and chairs sparsely occupied by students, laptops and textbooks are replaced once a week with rows of chairs occupied by the entire student and faculty population as the room is converted into a jam-packed auditorium ready to hear and imbibe the wise words of yet another distinguished guest lecturer. The Wednesday Seminar Series unites all of us through what may be considered as the fundamentals of science – cognition, dispersal of knowledge and assimilation of new information.
Usually seminars are addressed by scientists and academics from other institutes who can bring new concepts to the table, but this week we were pleasantly surprised to hear from ASBT’s very own Mr. Ajith Madhavan who spoke to us about his latest work on microbial fuel cells. Mr. Madhavan began his presentation with a thought-provoking question: Do invertebrates feel pain? As humans, we feel pain and pleasure as a means to perceive what is good and bad in the living environment. This emotional response is largely dependent on our advanced neural capacity – or in simpler terms, we feel pain (and other emotions) because we have a brain. But what about lower organisms that lack a brain? Recent studies have shown that cephalopods, such as squids, that lack an organized nervous system are capable of emotion. In fact, many brain-less organisms are actually quite intelligent. For example, slime mold (a protozoan) can effectively solve a maze to reach a food source and certain micro organisms are proficient at Sudoku puzzles. Mr. Madhavan thus connected the dots and proclaimed that based on these examples it is very much possible that micro organisms and other lower organisms also may feel pain.
If micro organisms can solve Sudoku and possibly have feelings, who is to say that they cannot also solve the planet’s energy crisis? Mr. Madhavan employs micro organisms to produce energy using microbial fuel cell (MFC). Micro organisms go through a series of cycles and pathways in order to survive, including the Electron Transport Pathway (ETP) in which bacteria release electrons which can be tapped as energy. In a two-chambered MFC, micro organisms interact with an anode in one chamber and in the presence of an oxidizing agent in the cathodic chamber scavenges electrons from the cathode. The two chambers are connected by an external circuit and connected to a load. In between the two chambers is a proton exchange membrane (PEM) which transports protons from the second chamber to the first and acts as a barrier for electrons. Therefore, a renewable source of energy can be maintained by just providing your bacterial culture with the proper nutrients to thrive and remain happy and satisfied (assuming they have emotions).
Mr. Madhavan has done extensive work on such MFCs and has experimented with various micro organisms and substrates to achieve high energy production. The phototropic MFC Mr. Madhavan designed using Synechococcus elongates using waste water as a substrate was able to generate approximately 10 mȦ and 1 volt of electricity. Other research in this area has even shown that using human urine can be used as a substrate for certain bacteria to produce enough energy to charge a mobile phone.
Although this microbial technology seems to be the “next big thing” (despite their small size) when it comes to renewable energy sources there is still a lot of work to be done before these bacteria batteries hit the market. As of now the MFCs are still much less efficient than solar cells and the search for the perfect bacteria and substrate continues. But with the help of researchers like Mr. Madhavan, perhaps the future may hold a world dependent on microbe-produced energy. The bacteria are ecstatic, I’m sure.
March 22, 2014
School of Biotechnology, Amritapuri