Solvent effects on the spectroscopic properties of aflatoxin B1

1. Solvent-induced changes in the spectral properties of aflatoxin B1 were investigated using protic and aprotic solvents. 2. The absorption data were less sensitive to solvent effects than the fluorescence emission data. 3. Stokes shifts in protic solvents were greater than those in aprotic solvents indicating hydrogen bond formation between solvent and the excited state of aflatoxin B1. 4. From the Stokes shift data for aprotic solvents, the dipole moment of aflatoxin B1 was estimated to increase by 15.7 Debye units upon excitation to the excited singlet state.     

Utilization of tannery solid waste for protease production by Synergistes sp. in solid‐state fermentation and partial protease characterization

Synergistes sp. DQ560074 produced a protease in submerged fermentation (SmF) at 400–420 U/mL and in solid‐state fermentation (SSF) at 745–755 U/g. The protease, which belongs to the aspartic protease class, was active over a wide range of pH (5–7) and at high temperatures (25–45°C). The protease is stable and active in various polar protic solvents (50% v/v) like ethanol, isopropanol, n–butanol, in polar aprotic solvents (50% v/v) like acetonitrile, and in non‐polar solvents (50% v/v) such as ethylacetate and toluene, but not in hydrophilic organic solvents (methyl alcohol and acetone). As far as we know, this is the first contribution to the production of a mesophilic protease with solvent stability in SSF using a proteinaceous solid waste.     

Effects of organic solvents on activity and stability of lipases produced by thermotolerant fungi in solid-state fermentation

Dried solid-state fermented solids (biocatalysts) produced by seven thermotolerant fungal strains were tested for lipase activity and stability in organic solvents. Two strains of Rhizopus sp. (19 and 43a) produced biocatalysts (L-19 and L-43a) that showed high lipase activities (74 and 72 U/g of dry matter, respectively) comparable to Lipozyme® RM IM (118 U/g DM). The use of the dipole moment of the organic solvents along with their classification based on the functional groups (non-polar, protic polar, aprotic polar) allowed the establishment of four different relative activity profiles for the seven biocatalysts evaluated. Compared to a biocatalyst not exposed to the organic solvent (100% relative activity), all biocatalysts showed a high relative activity (greater than 90%) in aprotic polar solvents (acetonitrile, acetone and ethyl acetate), whereas in protic polar solvents (ethanol and i-propanol) activity was reduced (lower than 40%). In addition, the incubation of biocatalysts L-19 and L-43a in i-amyl alcohol increased lipase activity in the synthesis of ethyl oleate 3.36 and 1.46 times, respectively. L-19 activity also increased after incubation in toluene (2.0 times), i-propanol (1.5 times) and acetonitrile (1.3 times) at temperatures from 30 to 50 °C. The results suggest that these biocatalysts can be used for a broad range of lipase reactions.     

Effects of solvent on inclusion complexation of a chiral dipeptide toward racemic BINOL

The effects of reaction solvent on inclusion complexation of a chiral dipeptide (3S,6S)‐ 1 derived from (S)‐proline toward racemic BINOL was investigated, discovering that the reaction solvent played a crucial role in determining the inclusion complexation behavior of dipeptide (3S,6S)‐ 1 toward rac‐BINOL. (3S,6S)‐ 1 did not show any chiroselective or achiroselective complexation toward rac‐BINOL in polar protic solvents such as methanol and ethanol, polar aprotic solvents including trichloromethane and THF, while in polar aprotic solvent ethyl acetate and apolar aprotic solvents benzene, (3S,6S)‐ 1 displayed achiroselective complexation toward rac‐BINOL. However, the resulting heterocomplex HC‐ 2 from benzene and HC‐ 3 from ethyl acetate have a different composition. Single crystal X‐ray diffraction analysis demonstrates that the two heterocomplexes are formed via different H‐bond interaction patterns, in which the reaction solvent has a dramatic effect. Furthermore, this work provides a relatively green method for quantitative enantiomeric enrichment of nonracemic BINOL, in which unacceptable and toxic benzene was replaced by ethyl acetate.     

Influence of solvents and leucine configuration at position 5 on tryptophan fluorescence in cyclic enkephalin analogues

The fluorescence decay of tryptophan is a sensitive indicator of its local environment within a peptide or protein. In this study we carried out fluorescence measurements of the tryptophan residue of cyclic enkephalin analogues of a general formula X-c[D-Dab(2)-Gly(3)-Trp(4)-Y(5)] where X = Cbz or H and Y = D- or L-Leu, in four solvents [water, methanol, acetonitrile, and dimethyl sulfoxide (DMSO)]. An analysis of the tryptophan fluorescence decays using a discrete-exponential model indicates that tryptophan fluorescence decay can be described by a double exponential function in all solvents studied. Lifetime distribution analysis yields a bimodal distribution in protic solvents (water and methanol), whereas an asymmetric, unimodal distribution in an aprotic solvent (DMSO) and uni- or bimodal distributions in acetonitrile solution, depending on leucine configuration. The data are interpreted in terms of the rotamer model, in which the modality and the relative proportions of the lifetime components are related to the population distribution of tryptophan chi(1) rotamers about the C(alpha)--C(beta) bond. The chirality of the Leu(5) residue and solvent properties affect the local environment of the tryptophan residue and therefore influence the distribution of side-chain rotamers. These results are consistent with the results of theoretical conformational calculations.     

Photophysical properties of dibenzofluorescein and the presence of its tautomers or prototropic forms in organic solvents.

The UV/Vis absorption and fluorescence properties of dibenzofluorescein (DBFL) in organic solvents were measured and used to shed light on the possible presence of its tautomers or various prototropic forms. DBFL in aprotic solvents mainly exists in two tautomeric forms, viz. quinoid and lactone, but neither are efficiently fluorescent. In protic solvents, such as methanol and ethanol, both the monoanion and neutral quinoid are present and showed the highest fluorescence quantum yield. In contrast, DBFL is fully dissociated to the monoanion and dianion in deionized water.     

Conformation of microtubule-bound paclitaxel determined by fluorescence spectroscopy and REDOR NMR

The conformation of microtubule-bound paclitaxel has been examined by fluorescence and solid-state NMR spectroscopy. A fluorescent derivative of paclitaxel, 3'-N-debenzoyl-3'-N-(m-aminobenzoyl)paclitaxel (N-AB-PT), was prepared by semisynthesis. No differences in the microtubule-promoting activity between N-AB-PT and paclitaxel were observed, demonstrating that addition of the amino group did not adversely affect the ligand-receptor association. The distance between the fluorophore N-AB-PT and the colchicine binding site on tubulin polymers was determined through time-resolved measurements of fluorescence resonance energy transfer to be 29 +/- 2 A. The absorption and emission spectra of N-AB-PT bound to microtubules and in various solvents were measured. A plot of the Stokes shift as a function of solvent polarity was highly unusual. The Stokes shift increased linearly with solvent polarity in protic solvents, which is expected due to the nature of the fluorophore. In aprotic solvents, however, the Stokes shift was invariant with solvent polarity, indicating that the fluorophore was somehow shielded from the effects of the solvent. These data are best explained by considering the solution-state conformational properties of paclitaxel. It is known that paclitaxel adopts different conformations depending on the nature of the solvent, and these fluorescence data are consistent with the molecule adopting a "hydrophobic collapsed" conformation in protic solvents and an "extended" conformation in aprotic solvents. The Stokes shift of microtubule-bound N-AB-PT was within the protic solvent region, demonstrating that microtubule-bound paclitaxel is in a hydrophobic collapsed conformation. Microtubule-bound paclitaxel was also investigated by solid-state NMR. Paclitaxel was labeled with (19)F at the para position of the C-2 benzoyl substituent and with (13)C and (15)N in the side chain. Distances between the fluorine and carbon nuclei were determined by REDOR. The distance between the fluorine and the 3'-amide carbonyl carbon was 9.8 +/- 0.5 A, and the distance between the fluorine atom and the 3'-methine carbon was 10. 3 +/- 0.5 A. These spectroscopic data were used in conjunction with molecular modeling to refine the microtubule-bound conformation of paclitaxel and to suggest an alternative orientation of the ligand within the paclitaxel binding site.     

Probing the interactions of alcohols with biological membranes with the fluorescent probe Prodan.

Prodan [6-propionyl-2-(dimethylamine)naphthalene] is a hydrophobic fluorescent probe which is extremely sensitive to both the polarity and the hydrogen-bond donating capacity of the solvent. In binary mixtures of solvents, the hydrogen-bond donating effect on Prodan fluorescence saturates at relatively low concentrations of protic solvent while the polarity effect is proportional to the mixture's dielectric constant. The fluorescence emission maximum is approximately a linear function of the dielectric constant in both protic and aprotic solvents, and this allows estimation of the dielectric constant in both environments. In phospholipid bilayers and biological membranes, Prodan exhibits two distinct emission peaks: blue (430-445 nm) and green (470-505 nm). Temperature determines the relative intensity of the two peaks, but their wavelengths depend on the type of membrane and appear to reflect a specific membrane environment. In phospholipid vesicles, alcohols reduce the fluorescence intensity of the blue peak and produce a red-shift in the emission maximum of the green peak. Taking the partition coefficients of the alcohols into account, short-chain alcohols are much more effective than longer-chain alcohols in red-shifting the emission maximum of the green peak. Alcohols have similar effects on Prodan fluorescence in liver microsomal and mitochondrial membranes, synaptosomal membranes, and red blood cell plasma membranes. However, in liver organelle membranes the red-shift of the green peak is the dominant effect while in plasma membranes the quenching of the fluorescence of the blue peak is dominant. These effects are observed at low (pharmacological) ethanol concentrations and provide a unique tool for probing the interactions of ethanol with biological membranes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Modulation of dual fluorescence in a 3-hydroxyquinolone dye by perturbation of its intramolecular proton transfer with solvent polarity and basicity.

A representative of a new class of dyes with dual fluorescence due to an excited state intramolecular proton transfer (ESIPT) reaction, namely 1-methyl-2-(4-methoxy)phenyl-3-hydroxy-4(1H)-quinolone (QMOM), has been studied in a series of solvents covering a large range of polarity and basicity. A linear dependence of the logarithm of its two bands intensity ratio, log(I(N*)/I(T*)), upon the solvent polarity expressed as a function of the dielectric constant, (epsilon- 1)/(2epsilon + 1), is observed for a series of protic solvents. A linear dependence for log(I(N*)/I(T*)) is also found in aprotic solvents after taking into account the solvent basicity. In contrast, the positions of the absorption and the two emission bands of QMOM do not noticeably depend on the solvent polarity and basicity, indicating relatively small changes in the transition moment of QMOM upon excitation and emission. Time-resolved experiments in acetonitrile, ethyl acetate and dimethylformamide suggest an irreversible ESIPT reaction for this dye. According to the time-resolved data, an increase of solvent basicity results in a dramatic decrease of the ESIPT rate constant, probably due to the disruption of the intramolecular H-bond of the dye by the basic solvent. Due to this new sensor property, 3-hydroxyquinolones are promising candidates for the development of a new generation of environment-sensitive fluorescence dyes for probing interactions of biomolecules.     

Synthesis and evaluation of molecularly imprinted polymers for enalapril and lisinopril, two synthetic peptide anti-hypertensive drugs

Molecularly imprinted polymers (MIPs) for the recognition of enalapril and lisinopril were prepared using 4-vinylpyridine as the functional monomer. Following thermal polymerisation the resulting materials were crushed, ground and sieved. First generation MIPs were produced in protic polar porogenic solvents (mixture of methanol (MeOH) and acetonitrile (ACN)). These MIPs were used and validated as sorbents for solid phase extraction and binding assays. Second generation MIPs were produced with polar aprotic porogenic solvent (DMSO). These polymers were packed in HPLC columns in order to investigate their molecular recognition properties in a dynamic mode. The study of the mobile phase composition included two major parameters: organic modifier content and pH value. Retention factors illustrate selective binding of the template from the imprinted polymers, compared to structurally related compounds.     

Solvent effects on fluorescence properties of protochlorophyll and its derivatives with various porphyrin side chains

Fluorescence spectra and fluorescence lifetimes of protochlorophyll (Pchl) were measured in organic solvents having different physical and chemical properties and were analyzed taking into account the nonspecific (dependent on bulk solvent parameters), and specific (e.g. H bonds, Mg coordination) solvent–solute interactions. The energy of the fluorescence emission band decreased, while the Stokes shift increased for increasing solvent orientation polarizability, which is a function of both the dielectric constant (ε) and the refractive index (n). The extent of the dependence of the Stokes shift on solvent orientation polarizability was higher in protic (i.e. those able to form hydrogen-binding) than in aprotic solvents. High value of the Stokes shift was also observed in pyridine and methanol, i.e. in solvents hexacoordinating the central Mg atom. The fluorescence decay of Pchl was monoexponential in all of the investigated solvents. The fluorescence lifetime decreased for increasing solvent orientation polarizability from 5.5 ± 0.1 ns in 1,4-dioxane to 3.3 ± 0.1 ns in methanol. Longer lifetime values were observed in the case of aprotic solvents than in protic solvents. The hexacoordination of Mg had no effect on the fluorescence lifetime. The present data are discussed with respect to results found for protochlorophyllide (Pchlide) (My?liwa-Kurdziel et al. in Photochem Photobiol 79:62–67, 2004), and they indicate that the presence of phytol chain in the porphyrin ring influences the spectral properties of the whole chromophore. This is the first complex analysis comparing the fluorescence emission and fluorescence lifetimes of purified Pchl and Pchlide.     

The Spectral Properties of (-)-Epigallocatechin 3-O-Gallate (EGCG) Fluorescence in Different Solvents: Dependence on Solvent Polarity

(-)-Epigallocatechin 3-O-gallate (EGCG) a molecule found in green tea and known for a plethora of bioactive properties is an inhibitor of heat shock protein 90 (HSP90), a protein of interest as a target for cancer and neuroprotection. Determination of the spectral properties of EGCG fluorescence in environments similar to those of binding sites found in proteins provides an important tool to directly study protein-EGCG interactions. The goal of this study is to examine the spectral properties of EGCG fluorescence in an aqueous buffer (AB) at pH=7.0, acetonitrile (AN) (a polar aprotic solvent), dimethylsulfoxide (DMSO) (a polar aprotic solvent), and ethanol (EtOH) (a polar protic solvent). We demonstrate that EGCG is a highly fluorescent molecule when excited at approximately 275 nm with emission maxima between 350 and 400 nm depending on solvent. Another smaller excitation peak was found when EGCG is excited at approximately 235 nm with maximum emission between 340 and 400 nm. We found that the fluorescence intensity (FI) of EGCG in AB at pH=7.0 is significantly quenched, and that it is about 85 times higher in an aprotic solvent DMSO. The Stokes shifts of EGCG fluorescence were determined by solvent polarity. In addition, while the emission maxima of EGCG fluorescence in AB, DMSO, and EtOH follow the Lippert-Mataga equation, its fluorescence in AN points to non-specific solvent effects on EGCG fluorescence. We conclude that significant solvent-dependent changes in both fluorescence intensity and fluorescence emission shifts can be effectively used to distinguish EGCG in aqueous solutions from EGCG in environments of different polarity, and, thus, can be used to study specific EGCG binding to protein binding sites where the environment is often different from aqueous in terms of polarity.     

Intramolecular and intermolecular hydrogen-bonding effects on photophysical properties of 2'-aminoacetophenone and its derivatives in solution.

Effects of intra- and intermolecular hydrogen-bonds on the photophysical properties of 2'-aminoacetophenone derivatives (X-C6H4-COCH3) having a substituted amino group (X) with different hydrogen-bonding ability to the carbonyl oxygen (X: NH2(AAP), NHCH3(MAAP), N(CH3)2(DMAAP), NHCOCH3(AAAP), NHCOCF3(TFAAP)) are investigated by means of steady-state and time-resolved fluorescence spectroscopy and time-resolved thermal lensing. Based on the photophysical parameters obtained in aprotic solvents with different polarity and protic solvents with different hydrogen-bonding ability, the characteristic photophysical behavior of the 2'-aminoacetophenone derivatives is discussed in terms of hydrogen-bonding and n,pi*-pi,pi* vibronic coupling. The dominant deactivation process of AAP and MAAP in nonpolar aprotic solvents is the extremely fast internal conversion (k(ic)= 1.0 x 10(11) s(-1) for AAP and 3.9 x 10(10) s(-1) for MAAP in n-hexane). The internal conversion rates of both compounds decrease markedly with increasing solvent polarity, suggesting that vibronic interactions between close-lying S1(pi,pi*) and S2(n,pi*) states lead to the large increase in the non-radiative decay rate of the lowest excited singlet state. It is also suggested that for MAAP, which has a stronger hydrogen-bond as compared to AAP, an intramolecular hydrogen-bonding induced deactivation is involved in the dissipation of the S1 state. For DMAAP, which cannot possess an intramolecular hydrogen-bond, the primary relaxation mechanism of the S1 state in nonpolar aprotic solvents is the intersystem crossing to the triplet state, whereas in protic solvents very efficient internal conversion due to intermolecular hydrogen-bonding is induced. In contrast, the fluorescence spectra of AAAP and TFAAP, which have an amino group with a much stronger hydrogen-bonding ability, give strongly Stokes-shifted fluorescence, indicating that these compounds undergo excited-state intramolecular proton transfer reaction upon electronic excitation.     

Immobilized radicals. IV. Biological semiquinone anions and neutral semiquinones

The semiquinone anion and neutral semiquinone radicals of benzoquinone, vitamin K-1, ubiquinone and plastoquinone were generated in both protic and aprotic solvents and frozen to produce immobilized spectra. The linewidths of the neutral semiquinones were always much larger than those of the corresponding anion radicals. Furthermore, the spectra of the neutral radicals often exhibit fine structure. When compared with in vivo spectra of semiquinones, these model systems suggest that the ubisemiquinone anion radical observed in photosynthetic bacteria can exist in either a protic or aprotic environment. There is also the implication that Signal II in chloroplasts may be a plastosemiquinone radical with a spin distribution similar to that of the neutral radical.     

Photophysical behaviour of 1-(4-N,N-dimethylaminophenylethynyl)pyrene (DMAPEPy) in homogeneous media.

The photophysical behaviour of a new pyrene derivative, 1-(4-N,N-dimethylaminophenylethynyl)pyrene (DMAPEPy), in various solvents has been studied. Due to the presence of an ethynyl link with a cylindrical pi cloud between the donor (N,N-dimethyl group) and the acceptor (pyrene), the molecule shows efficient intramolecular charge transfer, with a high extinction coefficient in all the solvents. There is significant solvatochromism in the fluorescence with a large increase in the Stokes' shift of around 125 nm between n-hexane and acetonitrile. The solvent-dependent spectral data show a good correlation with the Kamlet-Taft solvent polarity parameter (pi*). The plots of Stokes' shifts with E(T)(30) are linear for non-protic solvents and for protic solvents but with different slopes. The fluorescence quantum yields are high for non-polar solvents and decrease as the solvent polarity increases. Unlike the parent molecule pyrene, DMAPEPy shows a short lifetime, which is fairly insensitive to oxygen-induced quenching and is dependent on solvent polarity. The molecule shows high steady-state fluorescence anisotropy, which is very sensitive to the viscosity change of the medium.     

Stearic acid solubility and cubic phase volume

Stearic acid (SA) is highly soluble in structurally diverse solvents. SA/solvent packing within a (24.8 A)3 cubic volume explains the stoichiometry of SA solubility at multiple temperatures in multiple solvents. In the absence of solvent, the cubic volume contains 25 molecules at van der Waals distances from each other. At 55 degrees C, SA occupied half the cubic volume in saturated solution of four structurally diverse solvents. Below 4% SA/volume (e.g. in acetonitrile), the head and foot of each SA molecules on average is more than one solvent molecule away from the head and foot of a neighboring SA molecule. At 50% SA/cubic volume, -CH2- groups on SA molecules are separated from neighboring -CH2- groups on SA molecules by a monolayer of solvent molecules. Lowering the temperature from 55 to 25 degrees C, the volume fraction of SA decreased by a factor of 2 (or more) for every 6 degrees C. Lowering temperature increased the relative number of column of solvent molecules in the cubic phase, and correspondingly, the distance between SA molecules within the cubic volume increased. In three of five solvents, molecular mechanics calculations demonstrated the van der Waals stabilization that occurs from SA/SA affinity in the absence of solvent is similar in magnitude to the van der Waals stabilization from SA/solvent affinity. Methyl-t-butyl ether was less stabilized than hexane, acetone or methanol because the more bulky molecules packed less efficiently within the cubic volume. The most efficient/most stable packing however was still as columns of solvent between columns of SA. The efficiency and stability of SA and solvent packing optimal within the (24.8 A)3 cubic volume. Between 100 and 8% SA, multiple SA molecules present within the cubic volume function as SA aggregates. Both inter- and intra-cubic (phase) volume properties of SA aggregates coexist. Although acetonitrile and SA at the molecular level are both rod shaped, acetonitrile disrupted the packing of SA molecules within the cubic phase. The disrupted packing explains the much lower solubility of SA in acetonitrile than in the other solvents. The same molecular structures (e.g. methanol) can either stabilize or disrupt the packing of aggregated SA molecules, depending upon temperature. The mechanisms of aggregation within cubic volumes could also occur with structurally more complicated lipids. Aggregation and dispersion from such cubic phases could also be present in more complex chemical and/or macromolecular environments.     

Effect of water-miscible aprotic solvents on kyotorphin synthesis catalyzed by immobilized α-chymotrypsin

Summary Immobilized -chymotrypsin was used as catalyst to synthesize a kyotorphin derivative (Bz-Tyr-Arg-OEt) in the presence of five water-miscible aprotic solvents (dimethylsulphoxide, dimethylformamide, acetonitrile, acetone and tetrahydrofurane) at 30 °C. By using a kinetically-controlled approach, the maximum synthetic activity was obtained when Arg-OEt was used as nucleophile donor at a concentration 1.5-times higher than the acyl-acceptor substrate (Bz-Tyr-OEt). The water-miscible aprotic solvents enhanced greatly the synthetic activity proportionally to their hidrophilicity properties adequately measured by the log P parameter. At the optimum solvent concentration for the enzymatic peptide synthesis, both the water activity (Aw) of the media and the water content of the immobilized derivative showed a saturation profile against the log P parameter. As a function of the solvent hydrophilicity, these water parameters were shown as key parameters for the increase in the synthetic activity of the enzyme by the presence of these solvents.     

On protein solubility in organic solvent

Solubility of a model protein, hen egg-white lysozyme, was investigated in a wide range of neat nonaqueous solvents and binary mixtures thereof. All solvents that are protic, very hydrophilic, and polar readily dissolve more than 10 mg/mL of lysozyme (lyophilized from aqueous solution of pH 6.0). Only a marginal correlation was found between the lysozyme solubility in a non-aqueous solvent and the letter's dielectric constant or Hildebrand solubility parameter, and no correlation was observed with the dipole moment. Lysozyme dissolved in dimethyl sulfoxide (DMSO) could be precipitated by adding protein nondissolving co-solvents, although the enzyme had a tendency to form supersaturated solutions in such mixtures. The solubility of lysozyme, both in an individual solvent (1,5-pentanediol) and in binary solvent mixtures (DMSO/acetonitrile), markedly increased when the pH of the enzyme aqueous solution prior to lyophilization was moved away from the proteins's isoelectric point. (c) 1994 John Wiley & Sons, Inc.     

Picosecond kinetics of excited-state charge separation in 4-(dimethylamino)pyridine.

4-(Dimethylamino)pyridine (DMAP) shows solvent-dependent dual fluorescence from the initially excited state B* and a highly polar TICT state A*. Room-temperature time-resolved picosecond fluorescence investigations prove the bimodal kinetics of the excited-state electron transfer reaction B*-->A* in polar aprotic media. In medium polarity solvents (such as ethyl acetate) two emitting states of DMAP are shown to reach equilibrium within 50 ps. Both emitting states originate from the same ground state. The rate of excited-state charge separation depends on polarity and proton donating ability of the surrounding medium. The effects of temperature on the quantum yields of both fluorescences of DMAP in polar aprotic media indicate the transition from the kinetic regime (at low temperatures) to the equilibrium regime (at high temperatures). The kinetic behaviour of the dual luminescence of DMAP in protic solvents is more complex than in aprotic ones. In alcohols an efficient nonradiative channel competes with excited-state charge separation.     

Effect of various aqueous extracting agents on fluorescence properties of waste tea residue derived carbon dots (WTR-CDs): Comparative spectroscopic analysis

Fluorescent carbon dots (CDs) are one of the important carbonaceous nanomaterials in the area of nanoscience and nanotechnology because of their interesting physical as well as chemical properties. Herein we studied the effect of various aqueous extracting agents on fluorescence properties of waste tea residue-based carbon dots (WTR-CDs). WTR-CDs are firstly synthesized by utilizing kitchen waste-based carbonaceous biomass. To check the role of various aqueous media during the course of WTR-CDs synthesis from carbonized carbon powder, extraction of WTR-CDs was carried out in various kinds of aqueous media viz., only aqueous (100% water, WT), aqueous-alcoholic (10% ethanol, ET), aqueous-acidic (10% acetic acid, AA), and aqueous-basic (10% ammonia, AM). The consequences of extracting agents on the photophysical properties of final WTR-CDs-WT, WTR-CDs-ET, WTR-CDs-AA and WTR-CDs-AM were also discussed in detail. We have observed interesting blue shift fluorescence spectra in acidic medium for WTR-CDs-AA and polar protic solvents compared to polar aprotic medium. The solvatochromic behaviour of WTR-CDs-WT in model polar and non-polar solvent was also studied. The effect of cationic, anionic and non-anionic surfactants on the fluorescence of WTR-CDs-WT was also evaluated. The proposed findings may help researchers in the near future to obtain fast, easy and direct synthesize CDs from a variety of biomass-based precursors under different aqueous conditions.