scholarly journals Remediation potential of bacterial mixed cultures for polychlorinated biphenyls (PCBs) biodegradation

2019 ◽  
Vol 12 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Hana Horváthová ◽  
Katarína Lászlová ◽  
Katarína Dercová
Keyword(s):  
Polychlorinated Biphenyls ◽  
Mineral Water ◽  
Mixed Cultures ◽  
Contaminated Sediment ◽  
Bacterial Strains ◽  
Pcb Congeners ◽  
Naturally Occurring ◽  
Water Media ◽  
The Individual ◽  
Pcb Biodegradation

Abstract Remediation of polychlorinated biphenyls (PCBs) in minimal mineral water media in the presence of bacterial mixed cultures consisting of several individual strains is proposed. Starting from the fact that the properties and features of bacterial strains in mixed cultures can be supplemented and compensated, two-, three- and seven-membered mixed cultures (MC) were performed. The strains used for the construction of the MC were isolated from the waste canal of a former PCB producer. The highest biodegradation of 70 % of the sum of seven defined PCB congeners was achieved by two-membered MC containing the strains Rhodococcus sp. and Stenotrophomonas maltophilia added in the biomass ratio of 1 : 3 and 3 : 1. PCB biodegradation by a seven-membered MC was lower (58 %) but provided several benefits over the less-membered mixed cultures or the individual strains: similarity to naturally occurring microflora, easier preparation of the inocula, certain and repeatable results. Periodical reinoculation of the water media resulted to PCB biodegradation increase to 65 %. Seven-membered MC was applied to the historically PCB contaminated sediment as well, where a 59 % degradation of the sum of seven PCB congeners was determined.

scholarly journals Brominated Biphenyls Prime Extensive Microbial Reductive Dehalogenation of Aroclor 1260 in Housatonic River Sediment

1998 ◽  
Vol 64 (5) ◽  
pp. 1786-1795 ◽  
Author(s):  
Donna L. Bedard ◽  
Heidi Van Dort ◽  
Kim A. Deweerd
Keyword(s):  
Polychlorinated Biphenyls ◽  
River Sediment ◽  
Reductive Dehalogenation ◽  
Major Step ◽  
Anaerobic Microorganisms ◽  
Pcb Congeners ◽  
Naturally Occurring ◽  
Chlorine Removal ◽  
Pcb Dechlorination

ABSTRACT The upper Housatonic River and Woods Pond (Lenox, Mass.), a shallow impoundment on the river, are contaminated with polychlorinated biphenyls (PCBs), the residue of partially dechlorinated Aroclor 1260. Certain PCB congeners have the ability to activate or “prime” anaerobic microorganisms in Woods Pond sediment to reductively dehalogenate the Aroclor 1260 residue. We proposed that brominated biphenyls might have the same effect and tested the priming activities of 14 mono-, di-, and tribrominated biphenyls (350 μM) in anaerobic microcosms of sediment from Woods Pond. All of the brominated biphenyls were completely dehalogenated to biphenyl, and 13 of them primed PCB dechlorination. Measured in terms of chlorine removal and decrease in the proportion of hexa- through nonachlorobiphenyls, the microbial PCB dechlorination primed by several brominated biphenyls was nearly twice as effective as that primed by chlorinated biphenyls. Congeners containing a meta bromine primed Dechlorination Process N (flanked meta dechlorination), and congeners containing an unflanked para bromine primed Dechlorination Process P (flanked para dechlorination). Twoortho-substituted congeners, 2-bromobiphenyl and 2,6-dibromobiphenyl (2-BB and 26-BB), also primed Process N dechlorination. The most effective primers were 26-BB, 245-BB, 25-3-BB, and 25-4-BB. The microbial dechlorination primed by 26-BB converted ∼75% of the hexa- through nonachlorobiphenyls to tri- and tetrachlorobiphenyls in 100 days and removed ∼75% of the PCBs that are most persistent in humans. These results represent a major step toward identifying an effective method for accelerating PCB dechlorination in situ. The challenge now is to identify naturally occurring compounds that are safe and effective primers.

scholarly journals Differential Enantioselective Transformation of Atropisomeric Polychlorinated Biphenyls by Multiple Bacterial Strains with Different Inducing Compounds

2002 ◽  
Vol 68 (11) ◽  
pp. 5756-5759 ◽  
Author(s):  
Andrew C. Singer ◽  
Charles S. Wong ◽  
David E. Crowley
Keyword(s):  
Polychlorinated Biphenyls ◽  
Polychlorinated Biphenyl ◽  
Bacterial Strains ◽  
Pcb Congeners ◽  
Degrading Bacteria

ABSTRACT Five polychlorinated biphenyl (PCB)-degrading bacteria were tested for the ability to differentiate between the enantiomers of four atropisomeric PCB congeners (2,2′,3,6-tetra-CB; 2,2′,3,3′,6-penta-CB; 2,2′,3,4′,6-penta-CB; and 2,2′,3,5′,6-penta-CB) after growth in the presence of tryptone-soytone, biphenyl, carvone, or cymene. Enantioselectivity was shown to vary with respect to strain, congener, and cosubstrate.

scholarly journals Resolving Entangled JH-H-Coupling Patterns for Steroidal Structure Determinations by NMR Spectroscopy

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2643
Author(s):  
Danni Wu ◽  
Kathleen Joyce Carillo ◽  
Jiun-Jie Shie ◽  
Steve S.-F. Yu ◽  
Der-Lii M. Tzou
Keyword(s):  
Nmr Spectroscopy ◽  
1H Nmr Spectroscopy ◽  
Chemical Shifts ◽  
Atomic Level ◽  
Molecular Structures ◽  
Naturally Occurring ◽  
Structure Determinations ◽  
Ligand Interactions ◽  
Synthetic Steroids ◽  
The Individual

For decades, high-resolution 1H NMR spectroscopy has been routinely utilized to analyze both naturally occurring steroid hormones and synthetic steroids, which play important roles in regulating physiological functions in humans. Because the 1H signals are inevitably superimposed and entangled with various JH–H splitting patterns, such that the individual 1H chemical shift and associated JH–H coupling identities are hardly resolved. Given this, applications of thess information for elucidating steroidal molecular structures and steroid/ligand interactions at the atomic level were largely restricted. To overcome, we devoted to unraveling the entangled JH–H splitting patterns of two similar steroidal compounds having fully unsaturated protons, i.e., androstanolone and epiandrosterone (denoted as 1 and 2, respectively), in which only hydroxyl and ketone substituents attached to C3 and C17 were interchanged. Here we demonstrated that the JH–H values deduced from 1 and 2 are universal and applicable to other steroids, such as testosterone, 3β, 21-dihydroxygregna-5-en-20-one, prednisolone, and estradiol. On the other hand, the 1H chemical shifts may deviate substantially from sample to sample. In this communication, we propose a simple but novel scheme for resolving the complicate JH–H splitting patterns and 1H chemical shifts, aiming for steroidal structure determinations.

scholarly journals Polychlorinated biphenyls and risk of hepatocellular carcinoma in the population living in a highly polluted area in Italy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Francesco Donato ◽  
Marco Moneda ◽  
Nazario Portolani ◽  
Angelo Rossini ◽  
Sarah Molfino ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Polychlorinated Biphenyls ◽  
Serum Levels ◽  
Polluted Area ◽  
Sufficient Evidence ◽  
Pcb Congeners ◽  
Non Hodgkin Lymphoma ◽  
And Gender ◽  
Few Data ◽  
Incident Cases

AbstractPolychlorinated biphenyls (PCBs) are human carcinogens, based on sufficient evidence for melanoma and limited evidence for non-Hodgkin lymphoma and breast cancer. Few data are available for liver cancer, although PCBs cause it in rats and determined liver damage in poisoned people. We investigated the association between PCB serum levels and hepatocellular carcinoma (HCC) with a case–control study in a PCB-polluted area in North Italy. We enrolled prospectively 102 HCC incident cases and 102 age and gender-matched hospital controls. Serum concentrations of 33 PCB congeners were determined by a gas chromatograph coupled to mass spectrometry. Of 102 HCC cases, 62 who had lost < 3 kg of body weight in past 3 years were included in the analysis (67.7% males, mean age 68 years). The odds ratio (OR) for HCC for 3rd compared to 1st tertile of PCB distribution was 1.76 (95% confidence interval 0.62–5.03) for total PCB, adjusting for socio-demographic variables and risk factors for HCC by logistic regression. For most PCB congeners, ORs > 1.5 or 2 were found, although the 95% CIs included the null value for almost all of them. This preliminary study suggests that PCBs might play a role in HCC development.

scholarly journals Synthesis and Characterization of a Bioartificial Polymeric System with Potential Antibacterial Activity: Chitosan-Polyvinyl Alcohol-Ampicillin

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3109 ◽  
Author(s):  
Andres Bernal-Ballen ◽  
Jorge Lopez-Garcia ◽  
Martha-Andrea Merchan-Merchan ◽  
Marian Lehocky
Keyword(s):  
Antibacterial Activity ◽  
Polyvinyl Alcohol ◽  
Statistical Significance ◽  
Antibacterial Properties ◽  
Intermolecular Forces ◽  
Polymeric System ◽  
Bacterial Strains ◽  
Natural Polymers ◽  
The Matrix ◽  
The Individual

Bio-artificial polymeric systems are a new class of polymeric constituents based on blends of synthetic and natural polymers, designed with the purpose of producing new materials that exhibit enhanced properties with respect to the individual components. In this frame, a combination of polyvinyl alcohol (PVA) and chitosan, blended with a widely used antibiotic, sodium ampicillin, has been developed showing a moderate behavior in terms of antibacterial properties. Thus, aqueous solutions of PVA at 1 wt.% were mixed with acid solutions of chitosan at 1 wt.%, followed by adding ampicillin ranging from 0.3 to 1.0 wt.% related to the total amount of the polymers. The prepared bio-artificial polymeric system was characterized by FTIR, SEM, DSC, contact angle measurements, antibacterial activity against Staphylococcus aureus and Escherichia coli and antibiotic release studies. The statistical significance of the antibacterial activity was determined using a multifactorial analysis of variance with ρ < 0.05 (ANOVA). The characterization techniques did not show alterations in the ampicillin structure and the interactions with polymers were limited to intermolecular forces. Therefore, the antibiotic was efficiently released from the matrix and its antibacterial activity was preserved. The system disclosed moderate antibacterial activity against bacterial strains without adding a high antibiotic concentration. The findings of this study suggest that the system may be effective against healthcare-associated infections, a promising view in the design of novel antimicrobial biomaterials potentially suitable for tissue engineering applications.

Misperceptions of Friendly Behavior as Sexual Interest: A Survey of Naturally Occurring Incidents

1987 ◽  
Vol 11 (2) ◽  
pp. 173-194 ◽  
Author(s):  
Antonia Abbey
Keyword(s):  
Gender Differences ◽  
Gender Difference ◽  
Sexual Activity ◽  
Sexual Interest ◽  
Large Percentage ◽  
Future Research ◽  
Naturally Occurring ◽  
Retrospective Reports ◽  
Sexual Intent ◽  
The Individual

The studies described in this article examine retrospective reports of naturally occurring misperceptions of friendliness as sexual interest. Previous research has demonstrated that men perceive other people and situations more sexually than women do. The purpose of this research was to examine how this gender difference in perceptions of sexuality is exhibited in actual interactions between women and men. Two surveys of undergraduates were conducted. The results indicated that a large percentage of both women and men had experienced such misperceptions, although more women had than men. Most of these incidents were quickly resolved without problems; however, others involved some degree of forced sexual activity and left the individual feeling angry, humiliated, and depressed. Gender differences in the characteristics of these incidents and reactions to them are described. The implications of these findings for future research on gender differences in perceptions of sexual intent are discussed.

scholarly journals An Environmental Friendly Perspective of Microbial Degradation

2018 ◽  
Vol 3 (2) ◽  
Keyword(s):  
Heavy Metals ◽  
Polychlorinated Biphenyls ◽  
Microbial Degradation ◽  
Aromatic Hydrocarbons ◽  
Environmental Conditions ◽  
Cost Effective ◽  
Environmental Friendly ◽  
Naturally Occurring ◽  
Degradation Of Pollutants ◽  
Poly Aromatic Hydrocarbons

In the recent years attempt to find cost-effective and ecological ways to deal with noxious waste led mankind to focus on the use of microbes for the degradation of pollutants. These environmental friendly remediation methods employs the microbial naturally occurring catabolic capabilities to alter, vitiate or accrue a large number of pollutants including poly aromatic hydrocarbons, polychlorinated biphenyls, radio nuclides ,heavy metals etc. High-through put analyses of environmentally relevant microbes provides an insight of their major degradative pathways as well as their competence to acclimate to altering environmental conditions.

scholarly journals Statement of the Committee of Human Nutrition Science of the Polish Academy of Sciences on the use of dietary supplements containing vitamins and minerals by adults

2021 ◽  
Author(s):  
Agata Wawrzyniak ◽  
Katarzyna Przybyłowicz ◽  
Lidia Wądołowska ◽  
Jadwiga Charzewska ◽  
Danuta Górecka ◽  
...  
Keyword(s):  
Side Effects ◽  
General Population ◽  
Dietary Supplements ◽  
Dietary Supplementation ◽  
Dietary Recommendations ◽  
Nutrition Science ◽  
Naturally Occurring ◽  
The Individual ◽  
Academy Of Sciences ◽  
Usual Diet

The use of dietary supplements (supplementation) is the individual enrichment of the diet with ingredients naturally occurring in food. As a rule, dietary supplements should be used periodically. In nutritional practice, there are many indications for dietary supplementation, but the decision to take dietary supplements should be made by consumers wisely and only in justified situations, when there is a risk that the usual diet does not provide vitamins and minerals in an amount adequate to meet dietary recommendations. However, we should remember about the real dangers of taking too large doses of vitamins and minerals. Many people using dietary supplements, especially several types at the same time, may experience undesirable side effects and deterioration of health, and in addition, people taking medicines may seriously disrupt or weaken the effect of the drug, or even lack the therapeutic effect of the drug. The document presents 10 steps and rules for the use of dietary supplements available on the market, which are addressed to the general population.

scholarly journals Bacterial degradation of a mixture of hydroxy- and metoxypolychlorinated biphenyls

2019 ◽  
Vol 486 (3) ◽  
pp. 307-311
Author(s):  
D. O. Egorova ◽  
T. I. Gorbunova ◽  
M. G. Pervova ◽  
K. A. Plotnikova ◽  
T. D. Kiryanova ◽  
...  
Keyword(s):  
Polychlorinated Biphenyls ◽  
Total Content ◽  
Bacterial Degradation ◽  
Specific Rate ◽  
Bacterial Transformation ◽  
Initial Concentration ◽  
Chemical Functionalization ◽  
Pcb Congeners ◽  
Total Absence ◽  
Rhodococcus Wratislaviensis

In this work, the possibility of combining the methods of chemical functionalization of a mixture of polychlorinated biphenyls before the formation of a mixture of hydroxy- and methoxy-chlorinated biphenyls and the bacterial transformation of the compounds obtained with the aim of their utilization was investigated. As a result of a 100% conversion, a mixture of compounds identified as methoxy- (30 compounds), hydroxy- (44 compounds) and methoxy (hydroxy) derivatives (47 compounds) was obtained by reacting a mixture of Sovol with MeONa in MeOH and DMSO. PCB congeners. The total content of all hydroxy derivatives was 77.2%. It was established that the strain Rhodococcus wratislaviensis KT112-7 carries out the destruction of 73-93% of this mixture at the initial concentration of 0.25-1.50 g/l. The best result was obtained with a decomposition of 0.1 g/l of a mixture of methoxy- and hydroxy-polychlorobiphenyls (on the 10th day the total absence of the starting compounds). The specific rate of destruction was in direct correlation with the initial concentration of the mixture. It has been shown that during bacterial transformation there is no accumulation of toxic intermediate compounds.

The Renal Aminoacidurias

1963 ◽  
Vol 9 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Harold A Harper ◽  
Paul D Doolan
Keyword(s):  
Amino Acids ◽  
Glomerular Filtration ◽  
Maximum Rate ◽  
Renal Tubule ◽  
Renal Tubules ◽  
Naturally Occurring ◽  
Clinical Interest ◽  
The Individual ◽  
Filtered Load ◽  
Metabolic Significance

Abstract The normal mechanisms whereby the renal tubules handle amino acids are reviewed as a basis for interpretation of the physiologic causes of the renal aminoacidurias. Under normal circumstances, the renal tubules reabsorb in excess of 93% of the amino acids filtered from the plasma. When the filtered load of amino acids is increased, as by intravenous injection of amino acids, there is an increase in both the amounts reabsorbed and those excreted, but the ability of the renal tubule to respond to an increased filtered load of amino acids is so great that a maximum rate of reabsorption has not been found in the human. However, the tubule does exhibit selectivity with respect to the reabsorption of each of the naturally occurring L-amino acids; furthermore, there is a much greater efficiency of reabsorption of the L as compared to the D isomers of the individual amino acids. The excretion of amino acids is influenced to an important degree by the glomerular filtration rate, as exemplified by studies in pregnant subjects as well as patients with renal disease affecting glomerular filtration. Several renal aminoacidurias of clinical interest are discussed with special reference to their diagnostic and metabolic significance.

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