During an informal visit to one of my relatives house at Kalarangiatta village in  Sukinda valley region of Odisha I came to know that people of that area are suffering from intestinal, lungs and skin diseases. I found Cr(VI) toxicity in the soil and water due to open cast chromite mining activities is the root cause of their problem. So I thought of developing a low cost, green method of  Cr(VI)remediation .

 I inoculated indigenous cyanoacterial strain Anabaena cylindrica to both K2Cr2O7 and mine water collected from TATA mines. It was  found  to uptake up to 92% Cr(VI) from K2Cr2O7 and up to 82% from mine effluent  when analysed in UV Vis Spectrophotometer. It confirmed Anabaena cylindrica can be potentially used for bioremediation.

Rice is the staple crop of that area. So, I conducted a field trial of Oryza sativa(crop-Rice, variety-Khandagiri) taking  five treatments  with four replications following Randomized Block Design. To my wonder its results were even better than my expectation. Various growth and yield parameters were higher when  Anabaena  immobilized in Poly (Acrylic Acid) grafted over Guar gum was used  as compared to free cells.

My innovation is development of  bioremediation of Cr(VI) by Anabaena cylindrica  immobilized in guargum grafted poly acrylic acid polymer. It is highly helpful for Cr (VI) remediation both mine effluent and also reclamation of overburden sites. In future I want to develop a product  that can be applied in spray form in the farmers field for greater area coverage.

Question / Proposal


Cr (VI) toxicity is a great matter of concern in the sukinda valley region. It has resulted in both environmental pollution and a threat to life and livelihood of the lakhs of villagers residing in and around the mines area. So I wish to develop an environment friendly, effective and economical method for remediation of Cr (VI).

Research question:

To test the bioremediation of Cr(VI) using  Anabaena cylindrica immobilized in PAA(Poly Acrylic Acid) polymer grafted over guar gum and to test its applicability in rice (Oryza sativa, var Khandagiri) .


i)    Use of native cyanobacterial strain Anabaena cylindrica immobilized in Poly (Acrylic Acid) polymer grafted over guar gum can increase the bioremediation potential of hexavalent chromium.

ii)   This technology would help in rice growth by reducing hexavalent chromium bioaccumulation in higher plants.

Expected outcomes:

It is expected that native cyanobacterial strain Anabaena cylindrica would  be able to detoxify hexavalent chromium to a considerable amount .The integration of polymer to the cyanobaceria would provide a growth matrix for  Anabaena   which in turn would help in crop growth.




The conventional methods used for heavy metals removal from wastewater are precipitation, coagulation, chemical reduction, ion exchange and adsorption (Ali et al., 2012; Ali, 2010; Ali and Gupta, 2006). However, it has been observed that these processes are costly and unreliable (Camargo et al., 2005). Fathima Benazir et al., 2010 revealed as an alternative to conventional methods biological approaches utilizing microorganisms has the potential for a highly selective removal of toxic metals coupled with considerable operational flexibility, which can be both in situ or ex situ in a range of bioreactor configurations. Kannan et al, 2010 studied the properties of filamentous cyanobacteria Anabaena flos-aquae in the remediation of chromium (75%). Nath et al, 2017 studied   use of micro-algal consortia regarding chromium adsorption taking four monocultures; Scenedesmus dimorphus, Chlorella sp., Oscillatoria sp. and Lyngbya sp. and their synthetic consortia.

In my studies I have taken indigenous cyanobacterial  strain  Anabaena cylindrica  which is able to uptake up to 92% Cr(VI) from K2Cr2O7 and up to 82%  from mine effluent which throws light for  its potential use in bioremediation of Cr(VI).

 Mine wastewater contaminated by Cr(VI) not only possess major environmental and human health problems but also affect the growth and productivity of plant communities (Anderson, 1972 ; Hufn and  Allaway,1973). Chromium toxicity results in inhibition of plant growth, chlorosis, reduced crop yield, delayed germination, senescence, premature leaf fall, biochemical lesions, loss of enzyme activities and reduced biosynthesis of metabolites. Stobrawa et al. (2008) reported that heavy metals taken up by plants from contaminated soil and water are toxic to growth performance of plants and possess a hidden threat to consumers. Ahmad et al (2011) revealed that effect of Cr(VI) was alarming on  all aspects of plant growth and the result was further worrying when Cr was found in rice shoots (ranged from3575-19150%higher in different chromium treated plants than that of control), roots (ranged from 1023-5869 % higher in different Cr treated plants compared with control) and rice seeds( ranged from 21-249 % higher in Cr treated plants  compared with control.

 In view of this, I felt the need to access the effect of Cr(VI) on the growth and yield parameters of rice plant, the staple crop of the region and to find out the efficacy of the bioremediation treatment on rice crop. Therefore, I conducted a field trial in rice (Oryza sativa, var Khandagiri)   taking five treatments with four replications following randomized block design. The treatments were T1: control (no chromium), T2: chromium contamination, T3: chromium contamination with Anabaena (free cells), T4: chromium contamination with polymer, T5: chromium contamination with Anabaena cylindrica immobilized in polymer matrix.  As expected, my experimental findings evidenced plants grown under T5 giving the best result.

This method would not only help in combating Cr (VI )pollution ,but also in treating the overburden sites which is a great threat to the entire ecosystem. It would improve crop (rice) production without affecting the quality of the produce .So it is having a tremendous impact on the community.

Method / Testing and Redesign




 Anabaena cylindrica is found to reduce hexavalent chromium both from the Potassium dichromate solution and mine effluent. It was also found  that the integration of Cr(VI) treatment by Anabaena cylindrica along with Poly (acrylic acid) grafted with guar gum would be very helpful as the polymer is  having high water absorbing capacity and are good chelaters and so when used in agricultural fields would not wash off of the ions by rain. I could find out from experiments that hexavalent chromium is affecting   heterocyst frequency and filament length of Anabaena cylindrica. Uptake of Cr (VI) by Anabaena is affected by change in temperature and pH. The   hexavalent chromium removal was found to be optimum within a   temperature range of   250to 290C at pH 7. The minimum concentration that inhibited the growth of Anabaena was   found to be 150ppm. Increase in anti oxidative enzyme activities of SOD and APx is helping Anabaena to grow under Cr (VI) stress condition. In the rice field experiment, it  was observed that, different growth parameters like, plant height (27%), inter-nodal distance (38.1%), quantum yield (4.1%), number of tillers per plant(57%),  number of panicles (59%), panicle length (56.6%), seeds per panicle (31.2%), total number of seeds (52.9%),  harvesting index (66%), grain yield per hectare(56.6%), 1000 seed weight(13%)  were higher when   Anabaena immobilized biomass was used in comparison  to Cr(VI) stress condition.  Further, Raman spectra analysis of paddy seeds  showed a conspicuous peak for Cr (VI) at 900cm- which is absent in all other treatments signifying the treatment is able to prevent movement of toxic Cr (VI)  to the seeds thus checking its entry into food chain. So Anabaena cylindrica immobilized in poly(acrylic acid) grafted guar gum  not only served as a good chelater but also able to produce  better quality and higher yield of rice. Bioaccumulation of Cr (VI) by immobilised Anabaena cylindrica could be potentially applicable in the use of mine effluents as well as reclamation of mine overburden. From the above study, it can be concluded that  Anabaena immobilised  in poly(acrylic acid) grafted guar gum  is the better way to remediate Cr(VI) pollution. This small step of bioremediation of hexavalent chromium would be a big leap towards sustainable development.



About me

Hello! I am Naisargik.

Science is the knowledge that helps us to navigate a sea of problems  faced by humanity. It quenches the thirst of curiosity of why, what, how. It shows the path to reveal truth. It helps to lead a better life. To me science is not a subject only to be taught within the four walls of a classroom. I believe in learning by doing. I enjoy solving problems big or small  and develop my own project. It gives me a chance to discover myself. It is my passion to do research based studies because it throws new challenges, which trigger the mind to think differently to find out a solution. I learn many things in the process. From class six onwards I have been participating in various national level science fairs including IRIS National Science Fair, CBSE National Science Exhibition, Children’s Science Congress, JNNSMEE etc. I was a part of TEAM India at ISEF (International Science and Engineering Fair) 2018 held at Pittsburg.

My inspiration is Dr A.P.J. Abdul Kalam. I have heard him once at Bhubaneswar who ignited my mind to take STEM, to dream big, a dream to be seen not in sleep but that will not allow you to sleep.

Getting an award at Google fair is like making a dream true and being recognized for the effort that I have put in my project. It would be a great inspiration to step ahead in the journey of scientific research.

Health & Safety

Health and safety

I have conducted the experiment at the laboratory of Dr Kishore CS Panigrahi at School of Biological Sciences, NISER (National Institute of Science Education and Research),Khorda, Bhubaneswar.

Standard microbiological and laboratory safety measures required for Anabaena cylindrica (BSL 1) were followed. Information regarding potential health hazard was shared and necessary precautionary safety measures like use of personal protective equipments, proper cleaning of working area etc  were taken to avoid any unpleasant incident. Utmost care for health and safety measures were taken. Dr Kishore CS Panigrahi has supervised me while conducting various experiments and handling of equipments. His contact details are  :

Dr. Kishore  CS Panigrahi, Reader F, School of Biological Sciences, NISER

Po-Bhimpur, Padanpur, Dist-Khordha-752050, Odisha

Mobile number-9439863130


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I express my sincere thanks to Dr Kishore CS Panigrahi , Reader (F), Department of Biological Sciences, NISER, Bhubaneswar, for his esteemed supervision, guidance, advice and providing the laboratory facility for conducting the experiment.

I   express my deep sense of gratitude to Dr Sailabala Padhi , Former Director, Centre of  Environmental Studies, Department of Forest and Environment, Government of Odisha for helping in isolation, identification and  characterization of cyanobacterial  strains collected from in and around areas of Sukinda  chromite mines.

I sincerely thank Dr. Rajeev Padbhushan, IRRI, Odisha for giving me rice seedlings, variety Khandagiri for experimentation.

 Further, I deeply acknowledge the moral support and encouragement extended by my parents and friends till the completion of project.