Synergistic Effect Of Mixture Research Articles

Smart Combinations of Bioactive Compounds in Fruits and Vegetables May Guide New Strategies for Personalized Prevention of Chronic Diseases.

There is ample scientific evidence suggesting that the health benefits of eating the right amounts of a variety of vegetables and fruit are the consequence of the combined action of different phytochemicals. The present review provides an update of the scientific literature on additive and synergistic effects of mixtures of phytochemicals. Most research has been carried out in in vitro systems in which synergistic or additive effects have been established on the level of cell proliferation, apoptosis, antioxidant capacity, and tumor incidence, accompanied by changes in gene and protein expression in relevant pathways underlying molecular mechanisms of disease prevention. The number of human dietary intervention studies investigating complex mixtures of phytochemicals is relatively small, but showing promising results. These studies have demonstrated that combining transcriptomic data with phenotypic markers provide insight into the relevant cellular processes which contribute to the antioxidant response of complex mixtures of phytochemicals. Future studies should be designed as short-term studies testing different combinations of vegetables and fruit, in which markers for disease outcome as well as molecular ('omics)-markers and genetic variability between subjects are included. This will create new opportunities for food innovation and the development of more personalized strategies for prevention of chronic diseases.

Clinical studies of synergistic effect of mixture of aegle marmelos and holarrhena antidysenterica extracts and use of aegle marmelos in silver nanoparticle synthesis

Clinical studies of synergistic effect of mixture of aegle marmelos and holarrhena antidysenterica extracts and use of aegle marmelos in silver nanoparticle synthesis

Eleven years of crop diversification alters decomposition dynamics of litter mixtures incubated with soil

AbstractAgricultural crop rotations have been shown to increase soil carbon (C), nitrogen (N), and microbial biomass. The mechanisms behind these increases remain unclear, but may be linked to the diversity of crop residue inputs to soil organic matter (SOM). We used a residue mixture incubation to examine how variation in long‐term diversity of plant communities in agroecosystems influences decomposition of residue mixtures, thus providing a comparison of the effects of plant diversification on decomposition in the long term (via crop rotation) and short term (via residue mixtures). Three crop residue mixtures, ranging in diversity from two to four species, were incubated for 360 d with soils from five crop rotations, ranging from monoculture corn (mC) to a complex five‐crop rotation. In response, we measured fundamental soil pools and processes underlying C and N cycling. These included soil respiration, inorganic N, microbial biomass, and extracellular enzymes. We hypothesized that soils with more diverse cropping histories would show greater synergistic mixture effects than mC. For most variables (except extracellular enzymes), crop rotation history, or the long‐term history of plant diversity in the field, had a stronger effect on soil processes than mixture composition. In contrast to our hypothesis, the mC soil had nearly three and seven times greater synergistic mixture effects for respiration and microbial biomass N, respectively, compared with soils from crop rotations. This was due to the low response of the mC soils to poor quality residues (corn and wheat), likely resulting from a lack of available C and nutrients to cometabolize these residues. These results indicate that diversifying crop rotations in agricultural systems alter the decomposition dynamics of new residue inputs, which may be linked to the benefits of increasing crop rotation diversity on soil nutrient cycling, SOM dynamics, and yields.

Mixture toxicity of nickel and zinc to Daphnia magna is noninteractive at low effect sizes but becomes synergistic at high effect sizes.

To incorporate metal mixture toxicity effects into risk-assessment procedures, more information is needed about combined and interactive effects of metal mixtures during chronic exposure. The authors investigated the toxicity of binary Ni-Zn mixtures in 2 independent full-factorial experiments using standard chronic (21-d) Daphnia magna reproduction toxicity tests. Global statistical analysis (i.e., when considering all investigated mixture treatments simultaneously) showed noninteractive effects according to the concentration addition model and significant synergistic effects according to the independent action model. However, treatment-specific statistical analysis revealed that both occurrence and type of interactive effect were dependent on the effect size at which Ni and Zn were combined in the mixture. Only noninteractive or weakly antagonistic effects occurred in mixture treatments in which each of the individual metals produced only weak adverse effects on its own (i.e., ≤20% reduction of reproductive performance). On the other side of the spectrum, synergistic mixture effects occurred in all mixture treatments where both metals already caused a > 20% (for independent action) and a > 40% (for concentration addition) effect on reproduction on their own. Because low effect sizes are the most relevant in most regulatory frameworks, the authors' data suggest that the concentration addition and independent action mixture toxicity models can both serve as conservative models for predicting effects of Ni-Zn mixtures. The present study highlights the importance of investigating metal mixture toxicity at low effect sizes and warns against extrapolating conclusions about metal mixture interactions from high to low effect sizes.

High-throughput screening assay for the environmental water samples using cellular response profiles

Chemical and physical analyses are commonly used as screening methods for the environmental water. However, these methods can only look for the targeted substance but may miss unexpected toxicants. Furthermore, the synergistic effects of mixture cannot be detected. In order to set up the assay criteria for determining various biological activities at a cellular level that could potentially lead to toxicity of environmental water samples, a novel test based on cellular response by using Real-Time Cellular Analyzer (RTCA) is proposed in this study. First, the water sample is diluted to a series of strengths (80%, 60%, 40%, 30%, 20% and 10%) to get the multi-concentration cellular response profile. Then, the area under the cellular response profile (AUCRP) is calculated. Comparing to the normal cell growth of negative control, a new biological activity index named Percentage of Effect (PoE) has been presented which reflects the cumulative inhibitory activity of cell growth over the log-phase. Finally, a synthetical index PoE50 is proposed to evaluate the intensity of biological activities in water samples. The biological experiment demonstrates the effectiveness of the proposed method.

Synergistic health effects between chemical pollutants and electromagnetic fields.

Humans and ecosystems are exposed to highly variable and unknown cocktail of chemicals and radiations. Although individual chemicals are typically present at low concentrations, they can interact with each other resulting in additive or potentially synergistic mixture effects. This was also observed with products obtained by radiation actions such as sunlight or electromagnetic fields that can change the effects of chemicals, such as pesticides, and metal trace elements on health. Concomitant presence of various pesticides and their transformation products adds further complexity to chemical risk assessment since chronic inflammation is a key step for cancer promotion. Degradation of a parent molecule can produce several by-products which can trigger various toxic effects with different impacts on health and environment. For instance, the cocktail of sunlight irradiated sulcotrione pesticide has a greater cytotoxicity and genotoxicity than parent molecule, sulcotrione, and questions about the impact of photochemical process on environment. Adjuvants were shown to modify the biological features of pesticides. Addition of other elements, metals or biological products, can differently enhance cell toxicity of pesticides or electromagnetic radiations suggesting a synergy in living organisms. Electromagnetic fields spreading, pesticide by-products and mixtures monitoring become greater for environmental contamination evaluations.

The combinational effects between sulfonamides and metals on nematode Caenorhabditis elegans

As emerging pollutants, antibiotic sulfonamides are continuously emitted into the environment and encounter those already-existing contaminants, e.g., heavy metals, which may cause toxicity interactions in polluted habitats. So far, the sulfonamide mixture effects and the combinational effects between sulfonamides and metals have been seldom studied. In this study, lifespan, lethality (24 and 120h), locomotion behavior and growth (96h) of Caenorhabditis elegans were measured after exposure to mixtures containing sulfonamides (sulfadiazine, sulfapyridine, sulfamethoxazole and sulfamethazine as representatives) and/or metals (cadmium, copper, lead and zinc as representatives) at environmental concentrations. Results showed that sulfonamides did not cause acute (24h) lethality at chosen concentrations, but they decreased the lifespan in a concentration dependent fashion. Moreover, sulfonamide mixtures caused synergisms at higher concentrations but antagonisms at lower concentrations on the subacute (120h) lethal effects. The toxicity interactions of sulfonamide mixtures were addition action on body bending frequency, and antagonism on reversal movement and body length. In sulfonamide and metal mixtures, the toxicity interactions were different in acute and subacute lethal results, indicating the influence of the exposure time. According to the comparison among effects of mixtures containing sulfonamides and/or metals, subacute lethality of sulfonamides was enhanced by metals based on the synergistic mixture effects, while their inhibitions on the growth and behavior were weakened by metals based on the antagonistic mixture effects. Our findings highlighted studies on combinational effects between emerging and common contaminants for more accurate environmental risk evaluation, and also urged further mechanism studies.

Isolation, Identification and Usefulness of Antifungal Compounds from Zuccagnia punctata for Control of Toxigenic Ear Rot Pathogens

Infusion, tincture and decoction of leaves of Zuccagnia punctata Cav. were assayed on growth of Fusarium verticillioides, F. graminearum sensu stricto, F. boothii, F. meridionale, F. subglutinans and F. thapsinum. The tincture showed the lowest IC50 on mycelial growth. A diethyl ether fraction of the tincture showed the highest antifungal activity in microdilution assays on F. verticillioides and F. graminearum. The antifungal constituents were separated by silica gel chromatography and identified as 2',4'-dihydroxychalcone, 2',4'-dihydroxy-3'-methoxychalcone and 7-hydroxy-3',4'-dimethoxyflavone. These chalcones had the lowest MIC and MFC values on F. verticillioides and F. graminearum sensu stricto. 2',4'-Dihydroxychalcone was mildly toxic and the remaining identified compounds were non-toxic in the brine shrimp assay. 2',4'-Dihydroxychalcone in mixtures with commercial food preservatives showed additive effects on F. graminearum sensu stricto and synergistic ones on F. verticillioides. 2',4'-Dihydroxy-3'-methoxychalcone showed synergistic effects in mixtures. Our results suggest that addition of chalcones to food preservatives allows reduction in the doses of the preservatives required for control of Fusarium species.

Synergistic effects of mixtures of iron ores and copper ores as oxygen carriers in chemical-looping combustion

Iron ore is a cheap and nontoxic oxygen carrier in chemical-looping combustion (CLC). However, it performs good recyclability while low reactivity in the CLC of solid fuels. Copper ore exhibits very high reactivity and oxygen uncoupling behavior, while suffers from tendency towards sintering and agglomeration during consecutive redox cycles at a higher temperature (e.g., 900–1000°C). In this work, mixtures of hematite and copper ore were used as oxygen carriers for CLC of syngas and coal. Through the isothermal redox experiments at 950°C in a thermogravimetric analyzer, it is found that there are synergistic effects between iron ore and copper ore, and copper ore could be more efficiently utilized when the mixing ratio of copper ore is maintained 10–20wt%. As the mixing ratio of copper ore is 20wt%, the reduction reaction of the mixer OC is no longer endothermic, which is beneficial to the controllability of the fuel-reactor temperature. The fluidized-bed experiments were carried out to verify the reactivity of the mixing ore OCs at 950°C. It is observed that the mixing OC with 20wt% copper ore has a better reactivity with the gasification products (especially H2) of low-volatile anthracite than the pure hematite, and leads to a higher fuel conversion rate and CO2 yield. The mixtures of iron ore and copper ore are expected to address simultaneously reactivity, recyclability, cost and environmental concerns of oxygen carriers.

Qualitative environmental risk assessment of photolytic transformation products of iodinated X-ray contrast agent diatrizoic acid

Recent studies have confirmed that the aquatic ecosystem is being polluted with an unknown cocktail of pharmaceuticals, their metabolites and/or their transformation products (TPs). Although individual chemicals are typically present at low concentrations, they can interact with each other resulting in additive or potentially even synergistic mixture effects. Therefore it is necessary to assess the environmental risk caused by these chemicals. Data on exposure is required for quantitative risk assessment of TPs and/or metabolites. Such data are mostly missing because of the non-availability of TPs and very often metabolites for experimental testing. This study demonstrates the application of different in silico tools for qualitative risk assessment using the example of photodegradation TPs (photo-TPs) of diatrizoic acid (DIAT), which itself is not readily biodegradable. Its photolytic transformation was studied and the photodegradation pathway was established. The aerobic biodegradability of photo-TPs under the conditions of an aquatic environment was assessed using standardized OECD tests. The qualitative risk assessment of DIAT and selected photo-TPs was performed by the PBT approach (i.e. Persistence, Bioaccumulation and Toxicity), using experimental biodegradation test assays, applying different QSAR models with several different toxicological endpoints and in silico read-across approaches. The qualitative risk assessment pointed out that the photo-TPs were less persistent compared to DIAT and none of them possessed any bioaccumulation threat. However, a few photo-TPs were predicted to be active for mutagenicity and genotoxicity, which indicate the need for further testing to confirm these predictions. The present study demonstrates that in silico qualitative risk assessment analysis can increase the knowledge space about the environmental fate of TPs.

Applications of thermal stepwise reactions on the co-gasification of coal and tobacco stems

The objective of this study was to better understand the gasification mechanisms between tobacco stems and coal in a carbon dioxide atmosphere. Shenhua bituminous coal with Chinese tobacco stems were studied using the SDT–MS–FTIR technique, to elicit information from the thermal decomposition curves coupled with the evolved gases analysis. Subsequently, the activation energy of each reaction was calculated. The experimental results show that: (1) there were synergistic effects of mixtures of tobacco stems and coal, while decreasing the gasification temperature of fixed carbon in coal and increasing the reaction rate; (2) the proportion of tobacco stems and coal has an important influence on the gasification reaction; (3) the alkali and alkali earth metals in the tobacco stems play an important role in the cogasification of coal and tobacco stems.

Persistent organic contaminants in Saharan dust air masses in West Africa, Cape Verde and the eastern Caribbean

Anthropogenic semivolatile organic compounds (SOCs) that persist in the environment, bioaccumulate, are toxic at low concentrations, and undergo long-range atmospheric transport (LRT) were identified and quantified in the atmosphere of a Saharan dust source region (Mali) and during Saharan dust incursions at downwind sites in the eastern Caribbean (U.S. Virgin Islands, Trinidad and Tobago) and Cape Verde. More organochlorine and organophosphate pesticides (OCPPs), polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyl (PCB) congeners were detected in the Saharan dust region than at downwind sites. Seven of the 13 OCPPs detected occurred at all sites: chlordanes, chlorpyrifos, dacthal, dieldrin, endosulfans, hexachlorobenzene (HCB), and trifluralin. Total SOCs ranged from 1.9–126ng/m3 (mean=25±34) at source and 0.05–0.71ng/m3 (mean=0.24±0.18) at downwind sites during dust conditions. Most SOC concentrations were 1–3 orders of magnitude higher in source than downwind sites. A Saharan source was confirmed for sampled air masses at downwind sites based on dust particle elemental composition and rare earth ratios, atmospheric back trajectory models, and field observations. SOC concentrations were considerably below existing occupational and/or regulatory limits; however, few regulatory limits exist for these persistent organic compounds. Long-term effects of chronic exposure to low concentrations of SOCs are unknown, as are possible additive or synergistic effects of mixtures of SOCs, biologically active trace metals, and mineral dust particles transported together in Saharan dust air masses.

Synergistic Effects of Four Heavy Metals on Photobacterium

The synergistic effects of mixtures of CdCl2, Ni (NO3)2, CuSO4, and ZnSO4 on photobacterium Q67 were predicted and evaluated by using models of concentration addition (CA), independent action (IA), effect summation (ES), ES with the exponent e (ESE), ES with the power of the number of components n (ESN), and integrated CA with IA based on multiple linear regression (MLR) model (ICIM). The effects of all mixtures were underestimated by CA, IA, ES, ESE, and ESN models, but were effectively predicted by the ICIM model.

Synergistic extraction of Ce(IV) and Th(IV) with mixtures of Cyanex 923 and organophosphorus acids in sulfuric acid media

The synergistic effect of mixtures of Cyanex 923 and organophosphorus acids including P204, P507 and Cyanex 272 in extraction of Ce(IV) and Th(IV) from sulfuric acid solutions has been investigated. Under the experimental conditions, the extraction of Ce(IV) presented an significant synergistic effect with the mixed extraction systems of Cyanex 923–P204, Cyanex 923–P507 and Cyanex 923–Cyanex 272. On the contrary, the extraction of Th(IV) showed significant antagonistic effects in the mixed systems. The separation factor for Ce(IV)/Th(IV) reached as 36.8 at a mole fraction of 70% Cyanex 923 in the Cyanex 923–P507 system. It is shown that the mixed extraction systems not only enhance the extraction efficiency of Ce(IV) but also improve the selectivity of Ce(IV) over Th(IV). Furthermore, a fractional extraction process (including 4 stages of extraction, 2 stages of scrubbing and 2 stages of stripping) with the mixed Cyanex 923–P507 to separate Ce(IV) from the bastnasite leach solution has been designed. Cerium solution of Ce2(SO4)3 and CeF3 nanoparticle were obtained with 99.8% and 99.9% purity, respectively.

Physical setting and natural sources of exposure to carcinogenic trace elements and radionuclides in Lahontan Valley, Nevada

In Lahontan Valley, Nevada, arsenic, cobalt, tungsten, uranium, radon, and polonium-210 are carcinogens that occur naturally in sediments and groundwater. Arsenic and cobalt are principally derived from erosion of volcanic rocks in the local mountains and tungsten and uranium are derived from erosion of granitic rocks in headwater reaches of the Carson River. Radon and 210Po originate from radioactive decay of uranium in the sediments. Arsenic, aluminum, cobalt, iron, and manganese concentrations in household dust suggest it is derived from the local soils. Excess zinc and chromium in the dust are probably derived from the vacuum cleaner used to collect the dust, or household sources such as the furnace. Some samples have more than 5 times more cobalt in the dust than in the local soil, but whether the source of the excess cobalt is anthropogenic or natural cannot be determined with the available data. Cobalt concentrations are low in groundwater, but arsenic, uranium, radon, and 210Po concentrations often exceed human-health standards, and sometime greatly exceed them. Exposure to radon and its decay products in drinking water can vary significantly depending on when during the day that the water is consumed. Although the data suggests there have been no long term changes in groundwater chemistry that corresponds to the Lahontan Valley leukemia cluster, the occurrence of the very unusual leukemia cluster in an area with numerous 210Po and arsenic contaminated wells is striking, particularly in conjunction with the exceptionally high levels of urinary tungsten in Lahontan Valley residents. Additional research is needed on potential exposure pathways involving food or inhalation, and on synergistic effects of mixtures of these natural contaminants on susceptibility to development of leukemia.

Acute toxicity of commonly used forestry herbicide mixtures to Ceriodaphnia dubia and Pimephales promelas

Because many herbicides selectively control specific species or types of vegetation, they are often applied as mixtures to achieve better control over undesirable vegetation. When herbicides are applied in forest ecosystems, streams, ponds, and other bodies of water are typically protected by buffer zones in which no herbicide is applied. However, in some landscapes, small wetlands and streams are difficult to see and avoid, thus the potential acute toxicity of herbicide mixtures to aquatic organisms is of interest, yet it has not been well-studied. We examined the acute toxicity of 23 different herbicide mixtures to Ceriodaphnia dubia and fathead minnows (Pimephales promelas) at environmentally relevant concentrations, and, where possible, characterized mixture interactions using Marking's Additive Index. Maximum exposure concentrations were equivalent to applying the maximum allowable rate for each component directly to the surface of a 6-in. deep pond with no dissipation following application. Under the conditions of this study, herbicide formulations containing Accord Concentrate (glyphosate), Arsenal AC (imazapyr), Chopper (imazapyr), Escort (metsulfuron methyl), Oust XP (sulfometuron methyl), and Velpar L (hexazinone) were not associated with appreciable acute toxicity to fathead minnows or C. dubia when used alone or in mixtures with each other and various surfactants and adjuvants. Herbicide mixtures for which Additive Indexes could be calculated exhibited primarily antagonistic or simple additive toxicity. In the few cases where synergistic toxicity was observed, the degree of synergism was slight, never exceeding approximately twice the effect estimated based on additive toxicity. Based on the results of this study, neither acute toxicity nor enhanced acute aquatic toxicity due to synergistic mixture effects appears to be a significant concern for applications of the herbicide mixtures most commonly used in forestry.

Synergistic effects in mixtures of two identically charged ionic surfactants with different critical micelle concentrations

Expressions for the critical micelle concentration (cmc) and activity coefficients as functions of surfactant composition in mixtures of two identically charged monovalent ionic surfactants are derived from the nonlinear Poisson–Boltzmann (PB) theory. For the special case of no added salt, the simple expression cmcα = xcmcα1 + (1 − x)cmcα2 is deduced, where the exponential parameter α > 1 depends on the number of ionic species in a surfactant molecule as well as the curvature of the self-assembled interface. Theoretical predictions are compared with cmc values obtained with some different experimental techniques for mixtures of the two cationic surfactants didodecyldimethylammonium bromide (DDAB) and dodecyltrimethylammonium bromide (DTAB) in water and in the absence of added salt. It is demonstrated that the PB theory generates significantly better agreement with experimental data than predicted by ideal behaviour or the regular mixture theory. We find that maximum synergistic effects occur at a DDAB mole fraction in solution y = 0.005. According to the PB theory, this very low value of y corresponds to a mole fraction of DDAB in the self-assembled interfacial aggregates equal to x = 0.995. Moreover, our calculations of the surfactant composition in the self-assembled interfacial aggregates above cmc demonstrate that the transition from small micelles to large bilayer aggregates is found to consistently occur at a mole fraction of DDAB equal to about x = 0.41–0.42, irrespective of the surfactant molar ratio in solution. Experimental observations strongly support the fact that concentrations of free surfactant, as well as the surfactant composition in the self-assembled interfacial aggregates, may be accurately calculated from the non-linear Poison–Boltzmann theory. On the other hand, a micelle-to-bilayer transition induced by changes in surfactant mole fraction in the self-assembled interfacial aggregates is consistent with neither ideal surfactant behaviour nor synergistic behaviour according to the regular mixture theory.

Prediction of joint herbicide action by biomass and chlorophyll a fluorescence

Søbye KW, Streibig JC & Cedergreen N (2011). Prediction of joint herbicide action by biomass and chlorophyll a fluorescence. Weed Research 51, 23–32. Summary The joint effect of binary mixtures of the 4-hydroxyphenylpyruvate dioxygenase inhibitor isoxaflutole with glyphosate and metribuzin on Beta vulgaris was analysed with dose–response curves. The hypothesis was to test divergence from the Additive Dose Model (ADM), as a reference model. The Fvj parameter [(Fm − Fj)/Fm] and two new parameters, based on the slope at the J and the I step of the Kautsky curve, measured 2 days after spraying, and biomass 3 weeks after spraying, were used as responses. Synergistic effects of mixtures of isoxaflutole with numerous herbicides have been patented and were thus the working hypothesis. The shapes of isoboles, a contour plot of all mixtures of two herbicides that give the same effect, was variable, but the results of the mixtures with isoxaflutole, however, did not show statistically significant departure from the ADM. This applies to all endpoints: biomass and the Kautsky curve parameters, Fvj, Slope-I and Slope-J. The variability of isobole shapes is discussed, as is the use of statistical assessment of isobole parameters. The parameters from the Kautsky curves after 48 h predicted the isobole just as well as biomass after 20 days and could be used as a rapid scan for the divergence of joint action of mixtures from the ADM, long before visible symptoms develop.

Synergistic separation of Co(II)/Li(I) for the recycling of LIB industry wastes by supported liquid membrane using Cyanex 272 and DR-8R

The separation of Co(II) and Li(I) from simulated solution of lithium ion battery (LIB) industry wastes has been studied by a supported liquid membrane (SLM) process. The synergistic effect of mixture of the extractants Cyanex 272 and DP-8R on the permeation rate and separation factor of Co(II) and Li(I) from dilute aqueous sulfate media using a supported liquid membrane (SLM) technique has been examined. A microporous hydrophobic PVDF film was used as the solid support for the liquid membrane. The extractants Cyanex 272 and DP-8R and mixture of those were used as mobile carriers. The effects of different parameter such as stirring speed, pH of the feed solution, extractant concentration in the membrane phase, Co(II)/Li(I) concentration in the feed solution, and H 2SO 4 strip acid concentration, on Co(II) flux ( J Co(II)) and Li(I) flux ( J Li(I)) have been studied and compared. For all of the systems studied, Co/Li are optimally separated in the acidic pH region of 5.0−6.0. The best separation factor of 497 was achieved at pH 5.00 using a mixture of Cyanex 272 and DP-8R at a concentration of 750 mol/m 3 in the membrane phase, a strip acid concentration of 100 mol/m 3, and a stirring speed of 350 rpm. The separation factors for all three systems under the respective optimum experimental conditions have been calculated and compared. Qualitatively, they follow the order: mixed-extractant system > Cyanex 272 > DP-8R. This sequence may be quantitatively expressed as: mixed-extractant system ≈ 3 × Cyanex 272 ≈ 15 × DP-8R.

Merocyanine solvatochromic dyes in the study of synergistic effects in mixtures of chloroform with hydrogen-bond accepting solvents

The molar transition energy ( E T) polarity values for the solvatochromic probes 2,6-diphenyl-4-(2,4,6-triphenylpyridinium)phenolate ( 1), 4[(1-methyl-4-(1 H)-pyridinylidene)-ethylidene]-2,5-cyclohexadien-1-one ( 2), and 4-[4-(dimethylamino)styryl]-1-methylpyridinium iodide ( 3) were collected in binary mixtures comprising chloroform and a hydrogen-bond accepting (HBA) solvent [dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMA), acetone or acetonitrile], aiming to investigate the ability of the chlorinated component to act as hydrogen-bond donating (HBD) solvent. Plots of E T as a function of X 2, the mole fraction of chloroform, were obtained and the data were analysed to investigate the preferential solvation (PS) of each probe in terms of both solute–solvent and solvent–solvent interactions. For dyes 1 and 2 a strong synergistic behavior was observed for all mixtures studied, indicating that the dyes are preferentially solvated by complexes formed through hydrogen bonding between chloroform and the HBA component in the mixtures. A study of 1 in deuterated chloroform with an HBA component (DMF and DMA) demonstrated that while almost no differences occur with the DMF mixtures, the presence of deuterated chloroform in its mixtures with DMA increases the synergistic effect, suggesting that it interacts more strongly with DMA, making its mixtures more polar. These data were successfully fitted to a model based on solvent-exchange equilibria. The features of the mixtures with dye 3 revealed a very different profile in comparison with the other two dyes, which suggests that in mixtures containing chloroform, the microenvironment of the dye seems to be important in determining the contribution of the structure resonances responsible for the stability of the dye.