Two-stage phyto-microremediation of tannery effluent by Spirodela polyrrhiza (L.) Schleid. and chromium resistant bacteria

2016 ◽  
Vol 216 ◽  
pp. 883-893 ◽  
Author(s):  
Asha Singh ◽  
Dhiraj Vyas ◽  
Piyush Malaviya
Author(s):  
Shanewaz Hossan ◽  
Saddam Hossain ◽  
Mohammad Rafiqul Islam ◽  
Mir Himayet Kabir ◽  
Sobur Ali ◽  
...  

Chromium (Cr) (VI) has long been known as an environmental hazard that can be reduced from aqueous solutions through bioremediation by living cells. In this study, we investigated the efficiency of reduction and biosorption of Cr(VI) by chromate resistant bacteria isolated from tannery effluent. From 28 screened Cr(VI) resistant isolates, selected bacterial strain SH-1 was identified as Klebsiella sp. via 16S rRNA sequencing. In Luria–Bertani broth, the relative reduction level of Cr(VI) was 95%, but in tannery effluent, it was 63.08% after 72 h of incubation. The cell-free extract of SH-1 showed a 72.2% reduction of Cr(VI), which indicated a higher activity of Cr(VI) reducing enzyme than the control. Live and dead biomass of SH-1 adsorbed 51.25 mg and 29.03 mg Cr(VI) per gram of dry weight, respectively. Two adsorption isotherm models—Langmuir and Freundlich—were used for the illustration of Cr(VI) biosorption using SH-1 live biomass. Scanning electron microscopy (SEM) analysis showed an increased cell size of the treated biomass when compared to the controlled biomass, which supports the adsorption of reduced Cr on the biomass cell surface. Fourier-transform infrared analysis indicated that Cr(VI) had an effect on bacterial biomass, including quantitative and structural modifications. Moreover, the chickpea seed germination study showed beneficial environmental effects that suggest possible application of the isolate for the bioremediation of toxic Cr(VI).


The present study deals with the metal tolerance as well as metal resistance characteristic in bacteria isolated from mostly tannery effluent contaminated soil. Seven chromium resistant bacteria (CrRB 1-7) were isolated for this study in LB medium amended with 100 mg/L filter sterilized hexavalent chromium (Cr(VI)) solution. The minimum inhibitory concentrations (MIC) of these gram positive and gram negative bacteria were found in the range of 350 – 450 mg/L of Cr(VI) concentration. Cr(VI) removal potential of these seven isolates were also studied. One isolate CrRB 1 possessed the ability to remove 98.4% Cr(VI) within 24h in LB medium. The effect of hexavalent chromium on their biomass growth potential were further observed. For CrRB1 least differences were found in doubling time calculated from growth curve in presence and absence of Cr(VI). CrRB 1 was then further studied in real life wastewater i.e. tannery effluent to evaluate its performance for removal of Cr(VI).The favorable outcomes encourages for the use of this isolate in green bioremediation technology for tannery industry. The subsequent reactor studies requires to reveal its performance for in-situ application.


2013 ◽  
Vol 5 (1) ◽  
pp. 165-170 ◽  
Author(s):  
Asha Singh ◽  
Piyush Malaviya

The present study assessed the tolerance of Spirodela polyrrhiza (L.) Schleid (giant duckweed) exposed to different concentrations (5% -100%) of chrome liquor for 7 days. Physiological conditions of S.polyrrhizaplants were monitored daily by measuring fresh weight and chlorophyll-a and chlorophyll-b. Fresh biomass of Spirodela plant showed concentration and duration dependent reduction with minimum value (5.71 g) reported on 7 d at 100% tannery effluent concentration. Likewise, significant reduction in chlorophyll-a and chlorophyll-b content wasobserved in concentration-duration dependent manner with maximum reduction reported to be 99.8% and 99.6% respectively on 7 d at 100% effluent concentration in comparison to control.


2019 ◽  
Vol 2 (4) ◽  
pp. 80 ◽  
Author(s):  
Navid Safa Nova ◽  
Md. Aftab Uddin ◽  
Tasnia Ahmed

Development of new drugs is needed to resist the situation of diseases caused by drug resistant bacteria for public health safety. Natural resource is a big source to find candidates having antibacterial activity and aquatic weed is such a natural resource possessing such activity. The current study was aimed to determine the effectiveness of sea weed (Sargassum muticum) and fresh water weed/duckweed (Spirodela polyrrhiza) against six bacterial isolates Klebsiella pneumonia, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Pseudomonas luteola and Bacillus subtilis. The potency of methanol and ethanol extracts of these weeds was compared to determine the best candidate of weeds in inhibiting bacteria. Both agar well diffusion method and micro dilution was done to observe the antibacterial activity. Ethanol extract of Sargassum muticum worked best against Pseudomans aeruginosa (30mm zone of inhibition) and no activity against Bacillus subtilis. Methanol extract of the same Sargassum muticum showed less activity compared to ethanol extract except for Bacillus subtilis where it showed 21mm zone of inhibition. Ethanol and methanol extracts of Spirodela polyrrhiza showed less antibacterial activity against the bacteria compared to Sargassum muticum. They showed no antibacterial activity against Klebsiella pneumonia and Staphylococcus aureus. On average, the extracts impart a significant antibacterial activity against these six bacteria which are resistant to several antibiotics. Even one of them (Escherichia coli) is resistant to 4th generation cephalosporin but still fairly susceptible for extracts. The antibacterial properties of these marine and freshwater weeds can be subjected to develop new therapeutics to inhibit the resistant bacteria.


2013 ◽  
Vol 7 (1) ◽  
pp. 190-196 ◽  
Author(s):  
Paolo Cherubino ◽  
Marco Puricelli ◽  
Fabio D’Angelo

Infection is a frequent cause of failure after joint replacement surgery. The infection rate after total hip arthroplasty (THA) has been reduced to 1-2% in the last years. However, it still represents a challenging problem for the orthopedic surgeon.Difficulty of therapeutic approach, and poor functional outcomes together with length of treatment and overall cost are the main burden of this issue. Even the diagnosis of an infected hip could be challenging although it is the first step of an accurate treatment. At the end, many cases require removing the implants. Afterwards, the treatment strategy varies according to authors with three different procedures: no re-implantation, immediate placement of new implants or a two-stage surgery re-implantation.Based on the most recently systematic review there is no suggestion that one- or two-stage revision methods have different re-infection outcomes.The two-stage implant-exchange protocol remains the gold standard. It is considered as the most efficacious clinical approach for the treatment of periprosthetic infection, especially in patients with sinus tracts, swelling, extended abscess formation in depth and infection of Methicillin ResistantStaphylococcus Aureus(MRSA), and other multidrug-resistant bacteria as reported in recent consensus documents.


Author(s):  
Sengshiu Chung ◽  
Peggy Cebe

We are studying the crystallization and annealing behavior of high performance polymers, like poly(p-pheny1ene sulfide) PPS, and poly-(etheretherketone), PEEK. Our purpose is to determine whether PPS, which is similar in many ways to PEEK, undergoes reorganization during annealing. In an effort to address the issue of reorganization, we are studying solution grown single crystals of PPS as model materials.Observation of solution grown PPS crystals has been reported. Even from dilute solution, embrionic spherulites and aggregates were formed. We observe that these morphologies result when solutions containing uncrystallized polymer are cooled. To obtain samples of uniform single crystals, we have used two-stage self seeding and solution replacement techniques.


2007 ◽  
Vol 177 (4S) ◽  
pp. 121-121
Author(s):  
Antonio Dessanti ◽  
Diego Falchetti ◽  
Marco Iannuccelli ◽  
Susanna Milianti ◽  
Gian P. Strusi ◽  
...  
Keyword(s):  

2007 ◽  
Vol 177 (4S) ◽  
pp. 120-120
Author(s):  
Pamela I. Ellsworth ◽  
Anthony Caldamone
Keyword(s):  

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