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Technology on Microbial Management

The technology of effective microorganisms – beneficial impact on global environments

       We humans today have become very concerned about ou r environment - and say that it is polluted - our lands, water sour ces and oceans. However if we really think about it - do we not cause this pollut ion ourselves? Are we not responsible? Can we do something about it without d rastically changing our lifestyles - in a small way beginning from our hous es and place of work to reduce the level of pollution? This would reduce the adver se effects of our activities on the environment significantly.

 

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Algae enlisted to produce biofuel using discarded papayas

       USA Algae are the star players in an effort by U.S. Department of Agriculture (USDA) scientists in Hilo, Hawaii, to produce a renewable source of oil for conversion into biodiesel to help meet the island state's energy needs. Lisa Keith, a plant pathologist with USDA's Agricultural Research Service (ARS), is spearheading the project at the agency's Daniel K. Inouye U.S. Pacific Basin Agricultural Research Center in Hilo. Over the past five years, she has been fine-tuning conditions under which Chlorella protothecoides algae can be coaxed into producing oil from discarded papayas and other unmarketable crops or byproducts, like glycerol.

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How Does Oxo-biodegradable Plastic Work?

       The chemical degradation process involves the reaction of very large polymer molecules of plastics, which contain only carbon and hydrogen, with oxygen in the air. This reaction occurs even without prodegradant additives but at a very slow rate. That is why conventional plastics, when discarded, persist for a long time in the environment. EPI’s TDPA® formulations catalyze or accelerate this reaction and increase the rate of the degradation by several orders of magnitude – i.e. 100’s to 1000’s of times faster, making TDPA® incorporated products degrade and physically disintegrate within a few weeks to 1-2 years, depending on the formulation and the disposal environment. To illustrate, a TDPA® incorporated plastic bag and a conventional plastic bag were hung on the fence and the difference in degradation rates was observed in the degradation test.

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How Microbes Clean Up Our Environmental Messes

       Microbes are nature's ultimate garbage disposal, devouring the dead, decomposing and inert material that litters Earth's surface. They're so good at it, in fact, that humans have taken an increasing interest in coercing them to clean up our environmental messes.

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Microbial degradation of steroid hormones in the environment and technical systems

       Steroid hormones are naturally produced by human an d animals. Most important steroids are 17 β -estradiol (E2), estrone (E1) (both estrogens), tes tosterone as well as the synthetic ethinylestradiol (EE2). All substances consist of f our carbon rings what makes them stable in the environment. Steroid hormones are secreted in u rine and mainly enter the environment by waste water treatment plant (WWTP) effluents. Th e problem of steroid hormones is that they are endocrine disruptors and can affect aquati c organisms such as fish. Effects like feminism of male fish have already been observed ne ar WWTP effluents. The most important process to remove the steroids is the mic robial degradation. Sorption and to minor extent photo degradation can also play a role in th e removal of these hormones. The degradation rates of E2, E1 and EE2 have been studi ed widely. It was found that E2 is oxidised to E1 in the first step. The half-live of this step is around 4 to 12 hours in aerobic water and soil. However, this step does not signifi cantly reduce the estrogenic potential. Further degradation of E1 needs the cleavage of one ring. Therefore, half-lives of E1 are significantly higher and observed E1 concentrations are normally higher than E2 concentrations. The degradation of E1 shows a linea r relationship with the removal of the estrogenic potential. The structure of EE2 is analo gue to E2 but there is an ethinyl group at one hydroxyl group containing C-atom. This group is normally vulnerable to microbial attack. A cleavage of this ring is therefore difficult what makes EE2 much more recalcitrant in the environment. Thus, EE2 has a big impact on the estr ogenic potential although the secreted amount is much smaller than that of E2 or E1. The d egradation rates of steroid hormones in anaerobic sediments are much smaller. Half-lives of anaerobic E2 degradation are in the range of tens of days. E1 and EE2 can often not be degraded under anaerobic conditions. Therefore these substances accumulate in these envi ronments. In the WWTP the half-lives of E2 are in the range of a few minutes under aerob ic and denitrifying conditions whereas E1 shows half-lives of up to one hour in the denitrifi cation tank. E2 and E1 are thought to be degraded metabolically, i.e. for the bacteria to gain energy. EE2 is degraded within 2 to 4 hours under aerobic conditions in the WWTP but is q uite persistent under denitrifying conditions. EE2 is thought to be degraded cometabol ically, i.e. incidentally without an energy gain for the organism, by an enzyme of nitrifying b acteria, but this is not fully understood yet. The much smaller half-lives in the WWTP compared wi th the natural systems are due to the much higher bacteria density. Nevertheless, it is s till controversial which part of the WWTP is most efficient concerning steroid removal. The meta bolic degradation pathway of E2 and E1 is still not clear. The metabolic initial cleavage of the aromatic ring of E1 was proposed forty years ago but the cleavage of the five-ring as init ial step was recently suggested, too. On the basis of electron density comparisons it was assume d that EE2 is firstly cleaved at the aromatic ring as well. On the other hand, the degra dation pathway of testosterone – the so called 9,10-seco pathway - is well described and st arts with the cleavage of a ring in the middle. To improve the efficiency of WWTP concernin g removal of steroid hormones an increased sludge retention time (SRT) and hydraulic retention time (HRT) as well as the introduction of the most efficient bacteria communi ty are of most importance.

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New plastic degrades in just three hours

       Plastic is a globally important product; its versatility means you’ll find it in everything from electronics to furniture, prosthetic limbs to vehicles. There’s no doubt that it plays a big part in society. But on the flip side—it’s an environmental disaster. Because it degrades slowly, it accumulates in landfills for hundreds of years and can gradually leach harmful chemicals that make their way into groundwater. It also builds up in our oceans and can harm or kill marine animals. Furthermore, burning or melting it can release toxic emissions into the air.

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