Isolation and screening of chromium resistant bacteria from industrial waste for bioremediation purposes

Chromium (VI) a highly toxic metal, a major constituent of industrial waste. It is continuously release in soil and water, causes environmental and health related issues, which is increasing public concern in developing countries like Pakistan. The basic aim of this study was isolation and screening of chromium resistant bacteria from industrial waste collected from Korangi and Lyari, Karachi (24˚52ʹ46.0ʺN 66˚59ʹ25.7ʺE and 24˚48ʹ37.5ʺN 67˚06ʹ52.6ʺE). Among total of 53 isolated strains, seven bacterial strains were selected through selective enrichment and identified on the basis of morphological and biochemical characteristics. These strains were designated as S11, S13, S17, S18, S30, S35 and S48, resistance was determined against varying concentrations of chromium (100-1500 mg/l). Two bacterial strains S35 and S48 showed maximum resistance to chromium (1600 mg/l). Bacterial strains S35 and S48 were identified through 16S rRNA sequence and showed 99% similarity to Bacillus paranthracis and Bacillus paramycoides. Furthermore, growth condition including temperature and pH were optimized for both bacterial strains, showed maximum growth at temperature 30ºC and at optimum pH 7.5 and 6.5 respectively. It is concluded that indigenous bacterial strains isolated from metal contaminated industrial effluent use their innate ability to transform toxic heavy metals to less or nontoxic form and can offer an effective tool for monitoring heavy metal contamination in the environment.

Heavy Metal Pollution Reduced the Potentiality of Pen Culture in the Wetland Aquaculture in an Urban Area of Bangladesh

The Belai beel serves as an important aquatic resource for the livelihood of the local community of the Gazipur district in Bangladesh. However, water pollution in recent times, mainly from industrial wastes and sewage effluents, may disrupt its aquatic environment. Thus, the purpose of the present study was to assess the potential area of pen fish culture in the Belai beel. The study was performed in the Rajbagan (L1), Kamaria (L2) and Rewla (L3) areas of the Belai beel. Grass carp, silver carp, common carp, catla and rui of 20–30 cm in size were stocked at a rate of 15,000 fish/ha and reared for 150 days in pens installed in the L1, L2 and L3 areas, respectively. The fishes were fed with mustard oil cake and rice bran. Maximum fish production was found in Rewla (12.97 ton/ha/150 days) compared to Rajbagan (8.85 ton/ha/150 days) and Kamaria (10.67 ton/ha/150 days) due to it having comparatively good quality water. There were significant differences in metal ion concentrations (p < 0.05) among the three fish pens. In the Rajbagan area, concentrations of Cd and Cu in the water coming from the industrial effluent canal exceeded the acceptable limit. Results indicated that the Rewla area was better than Rajbagan and Kamaria due to it having relatively good quality water for pen fish culture.

Histopathological analysis of selected organs of Oreochromis niloticus due to sub-lethal industrial effluents exposure.

On a daily basis, our environment is exposed to tons of a composite of industrial effluents, which has a negative impact on commercial fish production and, as a result, on humans. Present study was designed to evaluate the acute, sub-chronic, and chronic toxicity of a composite of raw industrial effluent from Sunder Industrial Estate in the freshwater fish Oreochromis niloticus biosystem by investigating at the histopathological changes in different organs such as heart, kidney, and muscle after exposure. Fish was exposed to 1/3 rd , 1/5 th and 1/10 th of predetermined LC 50 . Significant histopathological alterations in heart (myocarditis, pericardium bending and lifting) kidney (renal tube degeneration, glomerulus structural alteration and necrotic proximal tubule) and muscle (inflammation, atrophy and tumor) were observed in treated groups. After the sub-lethal exposure histological alteration index (HAI) was highest in chronic group as compared to the acute and sub-chronic group as HAI group D ? HAI group C ? HAI group B. Moreover physic-chemical parameters of water were found to be out of the range of the APHA standard approach.

A study on the utilization of rice husk as a biosorbent material for Cr (VI) removal from industrial effluent

Purpose: To study Cr (VI) removal from waste water using chromium-resistant bacterial strains in combination with rice husk. Methods: Two strains of Exiguobacterium sp. resistant to chromium (VI) were applied in the present work. Rice husk (RH) was used as an agricultural waste for Cr (VI) removal. The elimination of Cr from the husk was chemically facilitated using hydrochloric, sulphuric and citric acids, as well as formaldehyde and potassium dihydrogen phosphate Investigation of optimum physical factors such as pH, temperature, shaking speed and biomass concentration on Cr (VI) removal was carried out using citric acid-processed rice husk alone, and in combination of bacterial strains. Fourier transform infra-red (FTIR) spectroscopy was performed to determine the contributions of different functional groups involved in Cr (VI) binding. Scanning electron microscopy (SEM) of treated and untreated RH was also performed. Results: Citric acid-processed RH was most effective in the removal of chromate (97.3 %). The two bacterial strains combined with rice husk proved highly efficient in Cr (VI) removal from sterile and non-sterile industrial effluents. FTIR spectra showed the involvement of esters, amines and aliphatic functional groups in Cr (VI) binding, while SEM displayed the damaging effects of Cr (VI) on the surface of RH; however, bacterial inoculation minimized the damage. Conclusion: Exopolysaccharides from Exiguobacterium strains and citric acid-processed rice husk demonstrated high efficiency for Cr (VI) removal. Hence, RH with these bacterial strains are potential biosorbents for control of heavy metal contamination arising from industrial effluents.

Removal of chromium and Iron using mixed adsorbent for synthetic and industrial samples in a continuous column reactor

he results of the experiments showed that bed weight, flow rate, and initial metal ion concentration all play a role in the removal of Cr (III) and Fe (II). The optimized break through curve was obtained at 36cm bed height and 10ml/min for chromium where 97.5 to 100% removal was observed at a saturation time of 500-600 min. With the increase in bed height from 12cm to 36cm, both the breakthrough and saturation times for Cr (III) increased. The break through time at 12cm, 24cm, 36cm and 10ml/min for Cr (III) were 70 min, 105 min, and 35 min respectively. The saturation time for Cr (III) at 12cm, 24cm, 36cm and 10ml/min were 460 min, 490 min, and 500 min respectively. Similarly, the break through time for Fe (II) at 12cm, 24cm, 36cm and 10ml/min were 70 min, 80 min, and 100 min respectively. At 12cm, 24cm, 36cm, and 10ml/min, the saturation time for Fe (III) was 340 minutes, 360 minutes, and 430 minutes, respectively. Overall in the column performance comparison between synthetic solution and industrial effluents for chromium, synthetic solution performance was more superior at fixed volumetric flow rates of 10 ml/min and bed heights ranging from 12 cm to 36 cm But the reverse trend was observed in case of fixed bed heights of 36 cm (150 g) and variation of volumetric flow rates from 10ml/min to 30ml/min which indicates that industrial effluent performance was superior when compared to synthetic solution for heavy metal removal.

Assessment of groundwater quality of two selected villages of Nawada district of Bihar using water quality index

Unplanned discarding of industrial effluent, sewage, domestic and industrial solid waste, unwise use of insecticides, herbicides, pesticides, and fertilizer in agriculture are the major causes of groundwater quality reduction. In the present paper groundwater quality of the two selected village of Rajauli subdivision of Nawada district of Bihar was assessed using water quality index (WQI). The samples were figured out for the parameters such as temperature, pH, electrical conductivity (EC), total dissolved solids (TDS), alkalinity, dissolved oxygen (DO), total hardness (TH), chloride, calcium (Ca), magnesium (Mg), biochemical oxygen demand (BOD), and fluoride. All the parameters were found below the standard limits of Bureau of Indian Standard (BIS, 2012) except total hardness (328.1mg/l to 346.6mg/l), calcium (105.3mg/l to 122.6mg/l), magnesium (46.1mg/l to 55.7mg/l) and fluoride (4.8 to 4.9mg/l). Fluoride was observed more than 3 times than the standard permissible limit (1.5mg/l). Water quality index (WQI) was also applied on the obtained data to make it easy to understand. Based on WQI (including the fluoride), all the four sites fall in unfit for drinking category (250.79, 258.78, 281.78, 247.30) and in poor to very poor category (80.23, 88.19, 88.59, 64.60) excluding the fluoride from WQI calculation. Both the values of WQI shows that fluoride alone is not responsible for the degraded quality of water but other high concentration of salts is also responsible.

Impact of Various Types of Polluted Water, Rhizome Size and Water Depth on Sprouting of Common Cattail (Typha latifolia L.) Rhizomes

Three different studies were carried out in the Department of Weed Science, The University of Agriculture Peshawar, in January 2016 to examine the impacts of polluted water from various sources, water depths and rhizome size on the resprouting ability and establishment of common cattail rhizomes fragments after mechanical control. These experiments were arranged in Completely Randomized Design (CRD), replicated thrice. The selected experimental units were pots 20 inches wide and 12 inches deep. Typha latifolia L. rhizomes were placed in each pots and covered with a little silt to avoid it’s direct contact and desiccation from sunlight. The impacts of water quality on T. latifolia rhizomes sprouting were significant. Lowest ratio of sprouted and un-sprouted buds (50.00 % each), 1st sprout length (37.33 and 40 cm), average sprout length (17.47 and 16.96 cm), average biomass (9.99 and 10.27 g) and growth rate (0.172 and 0.196 g/day) were noted for saline water and industrial acidic effluents, respectively. However, highest rhizome sprouting was recorded for tap water applied as check followed by industrial effluent alkaline. The data regarding the impact of water depth on T. latifolia rhizome sprouting showed that sprouting (44.44 %), 1st sprout length (43.33 cm), average sprout length (20.99 cm), average sprout biomass (7.84 g), average diameter of the newly formed rhizome (0.24 cm) and growth rate (0.4233 g/day) were recorded for rhizomes placed at zero level water depth, while maximum buds sprouted at 4 inches water depth. Similarly, impact of rhizome size on resprouting revealed that minimum bud sprouting (44.44%), 1st sprout length (44.86 cm), average sprout length (0.93 cm) and biomass of newly formed rhizome (4.97 g) and minimum days to emergence (9) were noted for smaller rhizome length (2 buds) compared to longer rhizomes with 10 buds. Therefore, on the basis of our findings, saline and industrial effluent acidic, no standing water (zero water surface level) and shorter rhizome size resulted in least bud sprouting and minimized the chance of further infestation in an eco-friendly and ecological way without the use of herbicides. Whereas alkaline industrial effluents, standing water up to 4 inches and longer rhizome fragments enhanced sprouting and re-establishment of the T. latifolia and these strategies can be utilized where the aim is to grow and establish a good stand of T. latifolia for passive treatment and phytoremediation of industrial effluents, before draining the polluted water into fresh water bodies like rivers and streams.

Bioremoval of Different Heavy Metals in Industrial Effluent by the Resistant Fungal Strain Aspergillus niger

Developing countries are increasingly concerned with pollution due to toxic heavy metals in the environment. Unlike most organic pollutants which can be destroyed, toxic metal ions released into the environment often persist indefinitely circulating and eventually accumulating throughout the food chain thus posing a serious threat to mankind. The use of biological materials for heavy metal removal or recovery has gained importance in recent years due to their good performance and low cost. Among the various sources, both live and inactivated biomass of organisms exhibits interesting metal binding capacities. Their complex cell walls contain high content of functional groups like amino, amide, hydroxyl, carboxyl, and phosphate which have been implicated in metals binding. In the present study, Aspergillus niger was used to analyze the metal uptake from an aqueous solution. The determination of Cu+2, Pb+2, Cd+2, Zn+2, Co-2 and Ni+2 in samples was carried out by differential Pulse Anodic Voltammetry (DPASV) and the Voltammograms. Production of oxalic acid was carried out by submerged fermentation. The organism used in the present study has the ideal properties to sequester toxic metals and grow faster.