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.

Plants from Urban Parks as Valuable Cosmetic Ingredients: Green Extraction, Chemical Composition and Activity

The research on the possibilities of using biowaste from urban green areas is scarce. In this work, four plants, widely distributed in urban parks in Central Europe (Lotus corniculatus, Medicago lupulina, Knautia arvensis and Plantago major) were extracted using eco-friendly solvents based either on aqueous cyclodextrin solutions (hydroxypropyl-β-cyclodextrin or γ-cyclodextrin) or natural deep eutectic solvents based on glycerol, betaine and glucose. Metal content was determined using total reflection X-ray fluorescence (TXRF). The content of selected metabolites was determined using UV-VIS spectrophotometric methods and HPLC. Skin-related bioactivity was assessed using tyrosinase and elastase inhibition assays. The selected plants contained metals beneficial for skin health, such as zinc and calcium, while having a low content of toxic heavy metals. The extracts contained the bioactive phenolics such as quercetin, kaempferol, luteolin and apigenin. L. corniculatus was the most potent tyrosinase inhibitor, while K. arvensis showed the most pronounced elastase inhibitory activity. The employed solvents actively contributed to the observed bioactivity. The results indicate that the biowaste obtained from urban parks represents an ecologically acceptable alternative to conventional cultivation for the preparation of ecologically acceptable, high-value cosmetic products.

Soil additives immobilising heavy metals in contaminated soils

Addition of iron oxides, lime, clay minerals and other substances can be used to decrease the plant availability of toxic heavy metals such as Pb, Zn, and Cd. Extractability and consequently plant concentrations may be reduced in some cases by more than 50%. The assessment of remediation processes is supported by biomonitoring methods in the field with Plantago lanceolata and in the greenhouse by barley test experiments, in combination with extraction by ammonium nitrate.

Remediation of Toxic Heavy Metal Contaminated Soil by Combining a Washing Ejector Based on Hydrodynamic Cavitation and Soil Washing Process

Based on the features of hydrodynamic cavitation, in this study, we developed a washing ejector that utilizes a high-pressure water jet. The cavitating flow was utilized to remove fine particles from contaminated soil. The volume of the contaminants and total metal concentration could be correlated to the fine-particle distribution in the contaminated soil. These particles can combine with a variety of pollutants. In this study, physical separation and soil washing as a two-step soil remediation strategy were performed to remediate contaminated soils from the smelter. A washing ejector was employed for physical separation, whereas phosphoric acid was used as the washing agent. The particles containing toxic heavy metals were composed of metal phase encapsulated in phyllosilicates, and metal phase weakly bound to phyllosilicate surfaces. The washing ejector involves the removal of fine particles bound to coarse particles and the dispersion of soil aggregates. From these results we determined that physical separation using a washing ejector was effective for the treatment of contaminated soil. Phosphoric acid (H3PO4) was effective in extracting arsenic from contaminated soil in which arsenic was associated with amorphous iron oxides. Thus, the obtained results can provide useful information and technical support for field soil washing for the remediation of soil contaminated by toxic heavy metals through emissions from the mining and ore processing industries.

Bioremediation Trends on Mitigation of As(III), Cr(VI) and Organic Dyes From Aqueous Medium using Plant and Microbial Biomass: An Overview

Arsenic, chromium and organic dyes are the prominent carcinogenic agents, posing a serious health hazard. In current scenario, groundwater as well as surface water mostly contaminated by chemical complexes of As (III), Cr (VI) and organic dyes, these are leading hazardous threat to eco-system. Several mitigation techniques of As (III), Cr (VI) and organic dyes are available but efforts are going on to devise a novel method of removal of these toxicants. This review takes into account all the recent advances in the detoxification of contaminated water exploring removal mechanism by biosorption and bioaccumulation. The possibility of the removal of toxic heavy metals from an aqueous medium by plant and bacterial biomass has been discussed. Now a days, bioaccumulation and biosorption from plants and microbial sources has emerged as simple, effective and eco-friendly techniques for decontamination of these chemical compounds from water resources at very low cost. Many agricultural products and solid wastes have also been found suitable decontaminant of toxic heavy metals and dyes. A wide spectrum of medicinal and aromatic plants as well as aquatic plants available in abundance may also be utilized as potential remover of As (III), Cr (VI) and organic dyes. This article explained mechanism and application on detail aspects of bioremediation technology including conventional techniques with recent development. This review shows the trends and development of mitigation stretagies by bioremediation with latest updates.

An Acrylamide-degrading Bacterial Consortium Isolated from Volcanic Soi

In soil, polyacrylamide is a key source of acrylamide because it slowly decomposes into acrylamide. There has been a modest but steady rise in worldwide interest in microbe-mediated acrylamide decomposition as a bioremediation method. A bacterial consortium isolated from the volcanic soil of Mount Marapi, West Sumatra, Indonesia, was able to thrive on acrylamide in this study. Acrylamide-degrading bacteria grew best in the presence of 1 %(w/v) glucose with acrylamide as the sole nitrogen source. Optimum growth occurs in between 300 and 500 mg/L of acrylamide, pH between 6.5 and 8.0, and temperatures between 30 and 35 °C. The consortium can also grow on acetamide as the sole nitrogen source. Toxic heavy metals, such as mercury, silver and copper slowed down the growth of this consortium on acrylamide. This is the first report of an acrylamide-degrading consortium isolated from volcanic soils.

SURFACE WATER QUALITY IN KHARKIV RECREATIONAL AREAS: 2006-2020

The aim of the paper is to assess dynamics of water quality in four main recreational areas in Kharkiv and to develop recommendations for water quality improvement. Methods. Field and laboratory methods and analytical data processing. Results. The paper presents analysis of dynamics in water quality for four main recreational areas located in Kharkiv: Zhuravlevskiy Hydropark, Oleksiivskiy Lugopark, Udyanskiy Hydropark and Osnovyanske Lake. Period of study: 2006-2020, time: May-June and August-September. Average data are presented. Samples were analysed at certified Laboratory of Analytical Chemical Research of the Karazin Institute of Environmental Sciences. Laboratory data were compared with national UA standards and European ones. Conclusions were made for the following key parameters: dissolved oxygen and BOD5, total mineralization, biogenic substances content, oil products and surfactants, toxic heavy metals content. There is no specific dynamics on the pollution level. Conclusions. The following recommendations for improvement of water quality were developed: (i) to preform regular monitoring of water quality; (ii) to introduce regular and systematic control by one local authority; (iii) to improve infrastructure of recreational areas; (iv) to introduce regular cleaning of the recreational areas; (v) to install bio-WC; (vi) to install additional waste containers (preferably with separate waste collection); (vii) plant trees for better isolation from highways; (viii) to improve level of water treatment on WWTP; (ix) to create nature protected areas along rivers

Physical Separation of Contaminated Soil Using a Washing Ejector Based on Hydrodynamic Cavitation

A washing ejector is a pre-treatment technology used to remediate contaminated soil by separating fine particles. The washing ejector developed in this study is a device that utilizes fast liquid jets to disperse soil aggregates by cavitation flow. The cavitation phenomenon is affected by the Bernoulli principle, and the liquid pressure decreases with the increase in kinetic energy. The cavitating flow of the fluid through the Ventrui nozzle can remove surface functional groups and discrete particles. The main methodology involves the removal of small particles bound to coarse particles and the dispersion of soil aggregates. Particle collisions occur on the surface soil, such as the metal phase that is weakly bound to silicate minerals. It was observed that the dispersed soil affected the binding of toxic heavy metals and the mineralogical characteristics of the soil. The quantity of oxides, organic matter, and clay minerals affected the properties of the soil. An almost 40–60% removal efficiency of total metals (As, Zn, and Pb) was obtained from the contaminated soils. After treatment by a washing ejector, the volume of fine particles was reduced by 28–47%. When the contaminants are associated with particulates, separation using a washing ejector can be more effective. Therefore, physical separation improves the removal efficiency of heavy metals from soil aggregates.

Phytoremediation of EMS Induced Brassica juncea Heavy Metal Hyperaccumulator Genotypes

Buriganga, an economically important river of Dhaka, Bangladesh, is highly polluted by different toxic heavy metals. In this study, phytoremediation of EMS induced Indian mustard (Brassica juncea L) genotypes against three pollutants viz. lead (Pb), chromium (Cr) and cadmium (Cd) of Buriganga riverbank soil was assessed in field condition. Among 1-, 2- and 3% EMS induced genotypes, better seed germination rate, germination speed and plant survival rate were observed in 1% EMS induced genotype, BE21. The highest concentration of Pb, Cr and Cd were also obtained in the leaf of BE21 genotype and therefore was considered as a super-hyperaccumulator genotype. Concentration of Pb in the next generation of this genotype was approximately two-fold higher in the root (91.53 mg/kg dry weight, DW); three-fold higher in the shoot (33.31 mg/kg DW) and leaf (28.35 mg/kg DW), and more in the fruit (5.59 mg/kg DW) than the control. Concentration of Cr was approximately two-fold in the root (57.02 mg/kg DW), shoot (18.51 mg/kg DW) and leaf (14.98 mg/kg DW), and more in the fruit (6.15 mg/kg DW) of BE21 genotype compared to the control. Cd concentration was more in the root (1.96 mg/kg DW), leaf (0.52 mg/kg DW) and fruit (0.19 mg/kg DW) and less in the shoot (0.19 mg/kg DW) of BE21 genotype than the control. Root, shoot, leaf and fruit of BE21 altogether accumulated 98-, 73- and 87% Pb, Cr and Cd, respectively and can thus be utilized to remove heavy metals of Buriganga River. As like root, shoot and leaf, fruit also accumulated heavy metals; hence those plants which are used in phytoremediation should not be used as food or fodder. To the best of our knowledge, this is the first report of developing EMS induced hyperaccumulator genotype of B. juncea for phytoremediation of Buriganga riverbank soil of Bangladesh.

Nutrient composition and bioaccumulation of an edible aquatic insect, Pantala sp. (Odonata: Libellulidae) from the rice field

Numerous edible aquatic insects have unanticipated nutraceutical potential and are consumed in a variety of Thai locations. The proximate composition, amino acid, fatty acid, mineral, and heavy metal content of Pantala sp. (Odonata: Libellulidae) aquatic edible nymphs were determined using standard analytical methods in this study. Pantala sp. had a proximate protein content of 445.14±0.04%, a fat content of 4.93±0.05%, an ash content of 5.24±0.03%, a moisture content of 35.11±0.09%, and a total carbohydrate content of 9.60±0.11%. Total energy was 263.25±0.20 kcal/100 g, with fat energy accounting for 44.37±0.43 kcal/100 g. Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) analysis revealed that this insect was high in phosphorus, iron, and copper for human consumption. In comparison to other edible insects studied, they were also excellent calcium sources. Agilent 7890B Gas Chromatograph (GC) analysis revealed that it contains 236.67 mg/100g of omega-3 and 523.32 mg/100g of omega-6. While the amino acids examined using High Performance liquid Chromatography contained all essential amino acids. ICP-OES was used to determine the levels of cadmium (Cd), lead (Pb), and arsenic (As). Pantala sp. had the highest concentration of As (average = 2.827 ± 0.289 mg kg -1 ), followed by Cd (0.164 ± 0.007 mg kg -1 ) and Pb (0.158 ± 0.015 mg kg -1 ). Although the insects have nutraceutical potential, they also have toxic heavy metals in trace amounts, with the exception of As. This work could serve as a nutritional reference for local consumers interested in entomophagy.