The aim of this synthesis is to highlight and illustrate the approach adopted by TEEB: namely to show how economic concepts and tools can help equip society with the means to incorporate the values of nature into decision making at all levels.

The economics of ecosystems and biodiversity : mainstreaming the economics of nature : a synthesis of the approach, conclusions and recommendations of TEEB

Biodegradation is defined as the biologically catalyzed reduction in complexity of chemical compounds [1]. Indeed, biodegradation is the process by which organic substances are broken down into smaller compounds by living microbial organisms [2]. When biodegradation is complete, the process is called "mineralization". However, in most cases the term biodegra‐ dation is generally used to describe almost any biologically mediated change in a substrate [3].

/pdf/biodegradation-involved-microorganisms-and-genetically-4whsf03f3j.pdf

Biodegradation: Involved Microorganisms and Genetically Engineered Microorganisms

Keratinases are well-recognized enzymes with the unique ability to attack highly cross-linked, recalcitrant structural proteins such as keratin. Their potential in environmental clean-up of huge amount of feather waste has been well established since long. Today, they have gained importance in various other biotechnological and pharmaceutical applications. However, commercial availability of keratinases is still limited. Hence, to attract entrepreneurs, investors and enzyme industries it is utmost important to explicitly present the market potential of keratinases through detailed account of its application sectors. Here, the application areas have been divided into three parts: the first one is dealing with the area of exclusive applications, the second emphasizes protease dominated sectors where keratinases would prove better substitutes, and the third deals with upcoming newer areas which still await practical documentation. An account of benefits of keratinase usage, existing market size, and available commercial sources and products has also been presented.

Biotechnological applications and prospective market of microbial keratinases

Aquatic environments often receive wastewater containing pollutants such as antibiotics and heavy metals from hospital sewage, as well as contaminants from soil. The presence of these pollutants can increase the rate of exchange of resistant genes between environmental and pathogenic bacteria, which can make the treatment of various types of bacterial infections in humans and animals difficult, in addition to causing environmental problems such as ecological risk. In this study, two tetracycline-resistant Pseudomonas aeruginosa (EW32 and EW33), isolated from aquatic environments close to industries and a hospital in southeastern Brazil, were investigated regarding the possible association between tetracycline and heavy metal resistance. The isolate EW32 presented a conjugative plasmid with coresistance to tetracycline and copper, reinforcing the concern that antibiotic resistance by acquisition of plasmids can be induced by the selective pressure of heavy metals in the environment.

Aquatic environments polluted with antibiotics and heavy metals: a human health hazard

Currently, the heavy metal pollution is of grave concern, and the part of microorganism for metal bioremediation should take into account as an efficient and economic strategy. On this framework, the heavy metal stress consequences on exopolysaccharide (EPS)-producing agricultural isolate, Pantoea agglomerans, were studied. The EPS production is a protective response to stress to survive and grow in the metal-contaminated environment. P. agglomerans show tolerance and mucoid growth in the presence of heavy metals, i.e., mercury, copper, silver, arsenic, lead, chromium, and cadmium. EDX first confirmed the metal accumulation and further, FTIR determined the functional groups involved in metal binding. The ICP-AES identified the location of cell-bound and intracellular metal accumulation. Metal deposition on cell surface has released more Ca2+. The effect on bacterial morphology investigated with SEM and TEM revealed the sites of metal accumulation, as well as possible structural changes. Each heavy metal caused distinct change and accumulated on cell-bound EPS with some intracellular deposits. The metal stress caused a decrease in total protein content and increased in total carbohydrate with a boost in EPS. Thus, the performance of P. agglomerans under metal stress indicated a potential candidate for metal bioremediation. Graphical Abstract ᅟ.

Heavy Metal Stress and Its Consequences on Exopolysaccharide (EPS)-Producing Pantoea agglomerans

The present paper put forth the isolation and complete characterization of three bacterial isolates from different sites of East Calcutta Wetland (ECW). These isolates show tolerance to heavy metals like Ag, Al, Cu, Cr, Co, Ni, Pb and were found to be efficient metal accumulators as evident from Energy Dispersive X Ray Fluorescence (EDXRF) analysis and Transmission Electron Microscopy (TEM). Beyond intracellular accumulation, these isolates also show metal deposition in form of particles inside the cells which can further open up the area of microbe fabricated nanoparticle generation. The heavy metal accumulation in the cell can trigger different response mechanism such as change in cell morphology which was observed by scanning electron microscopy (SEM). The metal uptake property of these isolates can be applied for the heavy metal removal and recovery from industrial effluents.

Studies on Metal Microbe Interaction of Three Bacterial Isolates From East Calcutta Wetland

East Calcutta Wetland (ECW) is an example of wise use of cities solid and liquid waste
through integrated resource recovery, mainly for pisciculture, vegetable as well as paddy cultivation
and manure production. Amaranthus caudatus, Amaranthus blithum and Spinacia oleracea grown at
ECW were analyzed for their accumulation of elements using Energy Dispersive X Ray Fluorescence
(EDXRF) and compared to those grown in south eastern parts of West Bengal (Midnapur). The
objective was to analyze the health hazard, if any, underlying the use of wastewater and solid waste for
cultivation of green leafy vegetables at ECW. The following results were obtained upon comparing the
data collected from the two different sites: (a) higher accumulation in ECW grown plants of elements
like Ca, Cu and Pb in Amaranthus caudatus; of Ca in Amaranthus blithum; of Cl and Cu in Spinacia
oleracea, (b) for the same species grown in non-ECW site, higher concentration of elements like Mn
and Fe in Amaranthus caudatus; of Cl, Mn and Br in Amaranthus blithum; of Ca, Mn, Fe and Br in
Spinacia oleracea. The net consumption of the aforementioned elements per person per day was
calculated and found to be much below the Recommended Dietary Allowance (RDA) levels in all
cases. Thus the vegetables grown out of integrated resource recovery mechanism at East Calcutta
Wetland appear to be safe for human consumption. This further corroborated by the healthy
appearance of these vegetables. This result has profound implications of far reaching significance for
environmental management and health economics.

/pdf/integrated-resource-recovery-at-east-calcutta-wetland-how-1ntjy232jn.pdf

Integrated Resource Recovery at East Calcutta Wetland: How Safe is These?

The current study is on East Calcutta Wetland (ECW) which is a model for multi-use resource recovery system with activities like pisciculture and agriculture. The entire city's soluble waste is disposed into the raw sewage canals which finally drains into the shallow, flat bottom fish ponds called Bheri. These sewage fed fisheries act simultaneously for the purification process like removal of heavy metals, coliform reduction as well as fish production at a commercial scale. The fishes from these Bheri are analyzed for the extent of metal accumulation in them as compared with those collected from the fresh water ponds around Calcutta. This comparative study was done to access the risk involved, if any, in fish cultivation and its subsequent consumption from these wastewater fed fisheries. Two types of commonly consumed fishes were chosen for the study namely Labeo rohita and Cirrhinus mrigala. Analysis of elements like P, S, Cl, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr and Pb was done by Energy Dispersive X Ray Fluorescence (EDXRF) in order to quantify the level of accumulation. The analysis inferred that elements like Cr, Cu, Rb, Pb shows accumulation in substantial amount in both type of fishes collected from the sewage fed as well as freshwater sources. The uptake of these fishes by human population thereby causes the consumption of these elements in relatively higher level as compared to the Recommended Dietary Allowance (RDA). Thus consumption of waste water cultivated fishes pose no additional health hazard. The accumulation of these metals in fishes from both Bheri as well as fresh water pond put forth a plausible action of diverse microscopic population and certain geochemical factors acting beneath the phenomenon of sedimentation as well as biomagnification of metal in the fish pond and their subsequent uptake in the aquatic food chain.

/pdf/traditional-aquaculture-practice-at-east-calcutta-wetland-4hh10fv1lr.pdf

Traditional Aquaculture Practice at East Calcutta Wetland: The Safety Assessment

This research note is an attempt to understand the role of water hyacinth vis-a-vis metal removal mechanism operating in “Bheris” – the shallow flat bottom waste water fed fisheries, which are unique ecosystems found in West Bengal, India. This study approaches the question by analysing the extent of heavy metal accumulation in water bodies of varied origin and geographic location in and around east Calcutta wetland as well as in different parts of water hyacinth obtained from these locations. Wastewater fed fish ponds are found to have lesser metal accumulation compared to rainwater ponds. This may be partly due to strong bioremediation operating in the wastewater ponds as a result of the existing microbes as well as plankton community. The phenomenon of heavy metal accumulation at a site thus depends on the soil condition, ground water level and the biotic population inhabiting that site.

https://www.tandfonline.com/doi/pdf/10.1080/15693430701833427

Role of water hyacinth-mediated phytoremediation in waste water purification at east Calcutta wetland

Dairy wastewater (DWW) is nutritionally rich and extremely hazardous to the environment if discharged untreated. The conventional treatment is time-, labor-, and energy-intensive. A tailor-...

M. Sudarshan

Papers

Studies on Metal Microbe Interaction of Three Bacterial Isolates From East Calcutta Wetland

Integrated Resource Recovery at East Calcutta Wetland: How Safe is These?

Traditional Aquaculture Practice at East Calcutta Wetland: The Safety Assessment

Role of water hyacinth-mediated phytoremediation in waste water purification at east Calcutta wetland

Microbial Consortium–Based Conversion of Dairy Effluent into Biofertilizer