Extractive Spectrophotometric Detection of Sn(II) Using 6-bromo-3-hydroxy-2-(5-methylfuran-2-yl)-4H-chromen-4-one.

For the determination of tin(II) traces, an extractive spectrophotometric approach is devised. The applied method serves a powerful tool for determination of tin(II), involves the formation of yellow colored complex after the binding of 6-bromo-3-hydroxy-2-(5-methylfuran-2-yl)-4H-chromen-4-one (BHMF) and tin(II) in 1:2 stiochiometry in a slightly acidic medium (HCl). The complex shows absorbance at 434 nm with respect of the blank reagent. The outcomes of spectral investigation for complexation showed a Beer's range of 0-1.3 µg Sn mL-1, molar absorptivity, specific absorptivity and Sandell's complex sensitivity are 9.291 × 104 L mol-1 cm-1, 0.490 mL g-1 cm-1 and 0.002040 µg cm-2 at 434 nm that was stable for two days. The interferences study results showed that this method is free from interferences, when tested with metal ions including Ag, Be, Bi, Ca, Cd, Ce, Co, Hg, Mo, Re, Pt, Se,Ti, U, V, W and other common cations, anions, and complexing agents. The applied method is quite simple, highly selective, and sensitive with good re-producibility. This method has been satisfactorily by utilizing the proposed procedure, and its applicability has been tested by analyzing synthetic samples and an alloy sample of gunmetal. The procedure assumes this because of the scarcity of better methods for determining tin(II). The results are in good agreement with the certified value.

Evaluation of ultrasonication and carbonation-ultrasonication assisted convective drying techniques for enhancing the drying rates and quality parameters of ripe and raw banana (Musa) peel.

Raw and ripe banana (Musa Cavendish) peel slices were dried by application of ultrasonication (U) and carbonation-ultrasonication (CU) as pre-treatments for tray drying (T) at 60 °C. Lesser drying time and higher diffusivity was noticed in CU + T dried samples followed by U + T and T dried samples. Model 'Wang and Singh' was identified as the excellently fitting model to experimental data. SEM images of dried samples revealed the microchannels formation due to U treatment, which were more couloir after CU treatment. Water and oil holding capacity (WHC and OHC) for raw peel powders was higher than ripened peel powders at 40, 60 and 80 °C. WHC and OHC increased significantly after U + T drying or CU + T drying as compared to T drying for ripe and raw peel powder samples. Back extrusion force (BEF) varied from 67.42 to 69.22 N and from 84.6 to 86.02 N for ripe and raw peel samples respectively. Given treatments resulted in lesser colour change and Browning Index. But U + T or CU + T treatment did not affect BEF significantly. CU + T was deemed to be the appropriate drying technique for ripe and raw banana peel drying. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05535-9.

Antibacterial potential of hive bees honey from Himachal Pradesh, India.

This paper presents a pioneer study on the microbial diversity and antibacterial potential of hive bees (Apis cerana and A. mellifera) honey collected from Himachal Pradesh. In total, 26 bacteria (14 from A. cerana and 12 from A. mellifera) but no fungal isolate were recovered. Bee species and locations comparison in terms of bacterial load (log CFU/g) revealed maximum loads of 3.74 and 3.99 in the honey from A. cerana and Mandi location, respectively. The most prevalent strains (HC3, HC5, HC6, HC8 and HM2) were identified (16S rRNA ribotyping) as Staphylococcus haemolyticus (MT742636), "Bacillus subtilis subsp. stecoris" (MT742637), Bacillus safensis subsp. safensis (MT742638), "Bacillus zanthoxyli" (MT742639) and Bacillus safensis subsp. safensis (MT938911). The apiary honey displayed good to excellent inhibitory activity against Escherichia coli ATCC1041 whereas, fair to good against Bacillus subtilis ATCC6633, Pseudomonas aeruginosa ATCC10662, Salmonella typhi NCTC786 and Klebsiella pneumoniae ATCC13883, highlighting its use as a therapeutic agent. Furthermore, it can be effective in minimizing numerous side effects associated with the consumption of synthetic drugs for treating bacterial infections thereby signifying the role of honey as a healthier substitute for synthetic drugs.

Edible films developed from carboxylic acid cross-linked sesame protein isolate: barrier, mechanical, thermal, crystalline and morphological properties.

Films were developed from sesame protein crosslinked with three different carboxylic acids (malic acid, citric acid and succinic acid) at 1, 3 and 5% (w/w, on protein isolate basis). The effect of crosslinking on physical, mechanical, thermal and morphological properties was studied. Succinic acid crosslinked films exhibited least water vapor permeability the highest tensile strength and overall showed superlative properties among other films. X-ray diffraction showed single main crystalline reflection at 20° indicating amorphous structure of films. DSC curves of films indicated single melting peak in the range of 103-161 °C. All films exhibited weight loss in three stages. FTIR exhibited peak at 1700 cm-1 confirming crosslinking reaction between carboxylic acids and protein. Crosslinked films were compact, nonporous and smooth as compared to film from native sesame protein isolate.

Food caramels: a review.

Caramel, defined as coloring agent and as an antioxidant, is being used in several kinds of food products. It has been classified into 4 classes to satisfy the requirement of several food and beverage systems. The variation in its consistency owing to its basic content of milk solids, sugars, and fat has been studied. Several methods have been found to estimate the amount of color provided by caramel in food products. Various formulations have been cited for the production of caramel by eradicating the frequent areas of problems during its processing. Caramel has been used as a synthetic colorant replacer in the baking and beverage industries. Researchers have aimed to ascertain the contribution to the antioxidant activity of some caramel-containing soft drinks. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has established an acceptable daily intake (ADI) of Class I caramel color as "not specified"; that of Class II as 0-160 mg/kg body weight; that of Class III as 0-200 mg/kg body weight; and that of Class IV as 0-200 mg/kg body weight. This paper is an overview of the classification, physicochemical nature, formulations, coloring properties, antioxidant properties, and toxicity of caramel in different food systems.

Effect of storage conditions of egg on rheological properties of liquid whole egg.

In the present work the effect of storage conditions of egg on rheological properties of Liquid Whole Egg (LWE) prepared from stored eggs were evaluated using a Brookfield. Newtonian model and Ostwald-of-Waele (Power Law) model were fitted to the rheological data obtained by experiments, both represented a good adjustment to the rheological data. The Newtonian model has shown an R(2)value between 0.984 and 0.993 (P < 0.05) and 0.991 and 0.995 (P < 0.05) for LWE samples prepared from eggs stored at room temperatures and refrigerated temperatures. The Ostwald-of-Waele (Power Law) resulted in the best adjustment, presenting an average R(2) values higher than 0.99 in all the cases and further statistical analysis showed that power law model was appropriate to explain the correct rheological behaviour of LWE prepared from stored eggs. All the LWE samples showed pseudoplastic and thixiotropic behaviour in the experimental conditions.

Investigating the Effect of Supercritical Carbon Dioxide Treatment on the Rheological, Thermal, and Functional Properties of Plum (Prunus domestica L.) Kernel Protein Isolates.

Plum kernels are a promising source of dietary proteins that are irretrievably lost during processing. The recovery of these underexploited proteins could be eminently vital for human nutrition. Plum kernel protein isolate (PKPI) was prepared and exposed to a targeted supercritical carbon dioxide (SC-CO2) treatment to diversify its effectiveness in industrial applications. The impacts of SC-CO2 treatment at different processing temperatures (30-70 °C) on dynamic rheology, microstructure, thermal, and techno-functional characteristics of PKPI were investigated. The results revealed that the dynamic viscoelastic characteristics of SC-CO2-treated PKPIs showed higher storage modulus, loss modulus, and lower tan δ value than native PKPI, indicating greater strength and elasticity of the gels. Microstructural analysis showed that the proteins experienced denaturation at elevated temperatures and resulted in the formation of soluble aggregates, which increased the heat requirement for thermal denaturation of SC-CO2-treated samples. SC-CO2-treated PKPIs demonstrated a decline of 20.74% and 30.5% in crystallite size and crystallinity. PKPIs treated at 60 °C showed the highest dispersibility, which was 1.15-fold higher than the native PKPI sample. SC-CO2 treatment offers a novel path to improve the techno-functional properties of PKPIs and extend its use in food and non-food applications.

Structural modification of plum (Prunus domestica L) kernel protein isolate by supercritical carbon-dioxide treatment: Functional properties and in-vitro protein digestibility.

The effect of supercritical carbon dioxide (SC-CO2) treatment at different processing temperatures (30-70 °C) on the physico-functional properties, structural features, and in-vitro digestibility (IVPD) of plum kernel protein isolates (PKPI) was examined. The results revealed remarkable changes in the secondary structures of SC-CO2-treated PKPIs, including a decrease in α-helix proportion, a concomitant increase in ß-sheet content, and a considerable variation in random coils and ß-turn structures. The temperature rise increased the negative zeta potential to a maximum of 31.35 mV at 60 °C, exhibiting the colloidal stability of PKPI dispersions. SDS-PAGE analysis showed variations in the intensities of protein bands, indicating denaturation and aggregation at higher temperatures. These structural and molecular changes improved water-binding capacity (1.22-fold) and oil binding capacity (1.11-fold), wettability (1.12-fold), and the highest value in all the properties was recorded at 60 °C. Moreover, the highest IVPD value (21.58 %) and a distinguishable colour difference (∆E) of 8.11 was also obtained at 60 °C of the processing temperature. Therefore, SC-CO2 treatment-induced modification of PKPI contributed to the enhanced digestibility and techno-functional properties, which offered new prospects to extend its use in food applications.

Optimization of extraction of antioxidants from wheat bran (Triticum spp.) using response surface methodology.

In this study, the optimal conditions for the extraction of antioxidants from hard winter wheat bran (WH711) were determined using response surface methodology (RSM). A central composite face centred design was used to investigate the effects of three independent variables, namely solvent composition (%v/v), extraction temperature (°C) and time (minutes) on the responses; free phenolic content (FPC), total flavonoid content (TFC), total antioxidant activity (TAA), ferric reducing power (FRP), hydrogen peroxide scavenging activity (HPSA). Regression analysis showed that more than 90% of the variation was explained by the models of different responses. The optimal conditions for the antioxidantss extraction were found to be methanol concentration of 85%v/v, extraction temperature of 75 °C, extraction time of 45 min, for wheat bran. The experimental values of FPC, TFC, TAA, FRP and HPSA were 0.921 mg GAE/g bran (B), 0.4588 mg CE/g B, 0.01408 mM AAE/g B, 2.532 mM AAE/g B and 3.193 mM TE/g B, respectively which agreed with those predicted, thus indicating suitability of the model employed and the suitability of RSM in optimizing the extraction conditions.

Synergistic effect of microwave heating and hydrothermal treatment on cyanogenic glycosides and bioactive compounds of plum (Prunus domestica L.) kernels: An analytical approach.

The effects of microwave heating (450 W for 6 min), hydrothermal treatment (6, 9, and 12 h at 45 °C) and their combination on compositional characteristics, cyanogenic glycosides, color, and bioactive compounds of plum kernels have been studied. The conditions examined caused a significant reduction of 37.81, 72.17, 84.41, 91.24 and 98.02% in cyanogenic glycosides of differently treated plum kernels. Total phenolic and total flavonoid compounds of plum kernels showed hydrothermal time-dependent duration decline. The larger shifts in FT-IR spectra near 1157 cm-1 provided valuable insights on the reduction of cyanogenic glycosides during combined treatments. The variation of color attributes (L*, a*, b*), during combined treatments indicates a more reddish tonality of plum kernel samples. The combined effect of hydrothermal (12 h at 45 °C) and microwave heating (450 W for 6 min) proved to be an effective tool for neutralizing the toxic effect of cyanogenic glycosides, opening up possibilities for its use in food industries.

Lethal and sublethal effects of thiamethoxam, a neonicotinoid molecule, on colony performance of A. mellifera.

Among insect pollinators, honey bees, Apis mellifera (Hymenoptera: Apidae), are universally acknowledged, most important managed pollinators that also provide honey production. In recent years, neonicotinoids are widely used against a broad spectrum sucking pests. However, they also pose a major threat to the beekeeping industry. The present study aimed to quantify the impact of thiamethoxam, a second-generation, broad-spectrum neonicotinoid on foraging behavior, colony performance, and survival of Apis mellifera L. in mustard crop under semi-field (cage) and field conditions. Under semi-field conditions, the foraging activity of A. mellifera on mustard bloom reduced significantly on the 2nd day after spray of thiamethoxam as compared to pre-count and control. Significant decrease in brood area (7th to 21st day), nectar stores (7th to 28th day), and pollen stores (7th to 21st day) were also recorded after the spray. The bee mortality under semi-field conditions was significantly higher on the 1st and 2nd day after spray in comparison to control. Under field conditions, average bee activity remained statistically low up to the 12th day after spray on mustard bloom in comparison to pre-count and control. The effect of thiamethoxam under field conditions was less pronounced for bee mortality and colony parameters. Based on LD50, thiamethoxam was proved toxic to adults and larvae of A. mellifera.

Selectivity for La3+ ion by synthesized 4-((5-methylfuran-2-yl)methylene)hydrazono)methyl)phenol receptor and its spectral analysis.

The functionalized molecules with specific molecular sites appear to be a promising approach for detection of cation in UV-visible and fluorescence spectroscopy. The synthesized receptor 4-((5-methylfuran-2-yl)methylene)hydrazono)methyl)phenol MFMHMP was found selective for La3+ among Ag+, K+, Na+, Be2+, Mg2+, Ca2+, Eu3+, Al3+, La3+, Zr4+, Th4+, UO22+, Fe3+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+ and Hg2+ metal ions used as their nitrates by UV-visible spectroscopy and fluorescence spectroscopy. The binding nature of MFMHMP with La3+ ion was analyzed by UV-visible, fluorescence, IR, mass spectroscopy and cyclic voltammetric studies. The stoichiometry was established to be 1:1 by Benesi-Hildebrand, mole-ratio method and method of continuous variation (Job's method) with good association affinity K = 6.245 × 104 M-1. Computational studies and Density functional theory (DFT) calculation gives the proof of electron transfer during excitation and emission. Binding energy of complex through Density Function Theory -62.387 kcal/mol has also indication of strong binding. The electron transfer energy of Higher occupied molecular orbital (HOMO) to Lower unoccupied molecular orbital (LUMO) is about 4.662 eV for MFMHMP+La3+ Complex. Among that all transitions HOMO → LUMO + 8 and HOMO → LUMO + 9 play a key role for the blue shift transition during complexation.

High intensity ultrasound treatment of protein isolate extracted from dephenolized sunflower meal: Effect on physicochemical and functional properties.

The influence of high intensity ultrasound (HIUS) on physicochemical and functional properties of sunflower protein isolates was investigated. Protein solutions (10% w/v) were treated with ultrasound probe (20kHz) and ultrasound bath (40kHz) for 5, 10, 20 and 30min. Thermal stability of protein isolates was reduced as indicated by differential scanning calorimetry. Minimum thermal stability was observed at 20min of sonication and increased further with increase in treatment time indicating aggregation at prolonged sonication. SDS-PAGE profile of proteins showed a significant reduction in molecular weight. Further, surface hydrophobicity and sulfhydryl content increased after HIUS treatment indicating partial unfolding of proteins and reduction in the intermolecular interactions. The particle size analysis showed that HIUS treatment reduced the particle size. Less turbid solution were observed largely due to reduction in particle size. HIUS decreased the available lysine content in protein isolates. Solubility, emulsifying capacity, emulsion stability, foaming capacity, foam stability and oil binding capacity were improved significantly, while as, water binding capacity was decreased. The effect of HIUS on physicochemical and functional properties of sunflower protein isolates was more pronounced in probe sonication rather than bath sonication. Protein isolates with improved functional properties can be obtained using high intensity ultrasound technology.

Changes in total phenolic content and color of bottle gourd (Lagenaria siceraria) juice upon conventional and ohmic blanching.

Plant phenolics exist in a complex matrix and require a high separation capacity for analysis. Bottle gourd (BG) was blanched using conventional thermal and alternate thermal ohmic heating methods using different combinations of temperature (60-90°C) and time (1-5min), and the effect of these methods on total phenolic content (TPC) and color was examined. Complete characterization on the basis of the phenolic profile of unblanched, ohmically blanched, and conventionally blanched samples of BG was studied. Gas chromatography-mass spectrometry and Liquid chromatography-mass spectrometry were used to detect volatile and nonvolatile phenolic compounds, respectively. The color profiles of the unblanched and conventionally and ohmically blanched samples were studied via hunterLab colorimeter using L*, a*, and b* coordinates. The highest increase in TPC was observed at 80°C, 4 min and 90°C, 5min in the case of ohmic and conventional blanching, respectively. The conventionally and ohmically blanched samples both produced desirable green-color retention in comparison to the unblanched samples; however, highest retention was observed in the ohmically blanched samples. The ohmically blanched samples exhibited the maximum extraction of phenolic compounds and better color of BG juice in comparison to the other samples.

Combined effect of blanching and sonication on quality parameters of bottle gourd (Lagenaria siceraria) juice.

This study evaluated the combined effect of blanching and sonication treatment on selected quality parameters of bottle gourd juice (BGJ). Bottle gourd cubes were blanched and juice was extracted. Effect of frequency (20-50kHz), amplitude (50-90%) and time (10-30min) was also studied on quality parameters like titratable acidity (TA), pH, total soluble solids (TSS), physical stability (PS), ascorbic acid (AA), total phenolics (TP), total carotenoids (TC), browning index (BI), total plate count (TPC) and yeast & mold count (Y&M) of BGJ to derive the level of these parameters. Combined effect of blanching followed by sonication (BFS) showed significant (P⩽0.05) change in all quality parameters except TA. Highest percentage of TSS (5.9°B), PS (2%), AA (18.99mg/100g), TP (1010mg/100g) and TC (5.8mg/100g) was observed at 70% amplitude, 50kHz frequency and 20min. Results suggested 70% amplitude, 50kHz frequency and 20min as best treatment conditions for processing of BGJ. Microstructure examination, transmission electron microscopy (TEM) and laser diffraction analysis of BGJ showed significant change in particle size and distribution. Moreover, TEM of blanched and sonicated samples of BGJ also showed significant (P⩽0.05) change in microbial profile.

PVC-based dicyclohexano-18-crown-6 sensor for La(III) ions.

A new ion-selective electrode (ISE) based on dicyclohexano-18-crown-6 (DC18C6) as a neutral carrier is developed for lanthanum(III) ions. The electrode comprises of dicyclohexano-18-crown-6 (6%), PVC (33%), and ortho-nitrophenyl octyl ether (o-NPOE) (61%). The electrode shows a linear dynamic response in the concentration range of 10(-6) to 10(-1)M with a Nernstian slope of 19mV per decade and a detection limit as 5x10(-7)M. It has a response time of <30s and can be used for at least 5 months without any significant divergence in potentials. The selectivity coefficients for mono-, di-, and trivalent cations indicate good selectivity for La(III) ions over a large number of interfering cations. The sensor has been used as an indicator electrode in the potentiometric titrations of La(III) with EDTA. The membrane is successfully applied in partially non-aqueous medium. It can be used in the pH range 4-9.