Extraction of pigments from endophytes is an uphill task. Up till now, there are no efficient methods available to extract the maximum amount of prodigiosin from Serratia marcescens. This is one of ...the important endophytes of Beta vulgaris L. The present work was carried out for the comparative study of six different extraction methods such as homogenization, ultrasonication, freezing and thawing, heat treatment, organic solvents and inorganic acids to evaluate the efficiency of prodigiosin yield. Our results demonstrated that highest extraction was observed in ultrasonication (98·1 ± 1·7%) while the lowest extraction by freezing and thawing (31·8 ± 3·8%) methods. However, thin layer chromatography, high‐performance liquid chromatography and Fourier transform infrared data suggest that bioactive pigment in the extract was prodigiosin. To the best of our knowledge, this is the first comprehensive study of extraction methods and identification and purification of prodigiosin from cell biomass of Ser. marcescens isolated from Beta vulgaris L.
Significance and Impact of the Study
The prodigiosin family is a potent drug with anticancer, antimalarial, antibacterial, antifungal, antiproliferative and immunosuppressive activities. Moreover, it has immense potential in pharmaceutical, food and textile industries. For the industrial perspective, it is essential to achieve purified, high yield and cost‐effective extraction of prodigiosin. To the best of our knowledge, this is the first comprehensive study on prodigiosin extraction and also the first report on endophyte Serratia marcescens isolated from Beta vulgaris L. The significance of our results is to extract high amount and good quality prodigiosin for commercial application.
Significance and Impact of Study: The prodigiosin family is a potent drug with anticancer, antimalarial, antibacterial, antifungal, antiproliferative and immunosuppressive activities. Moreover, it has immense potential in pharmaceutical, food and textile industries. For the industrial perspective, it is essential to achieve purified, high yield and cost‐effective extraction of prodigiosin. To the best of our knowledge, this is the first comprehensive study on prodigiosin extraction and also the first report on endophyte Serratia marcescens isolated from Beta vulgaris L. The significance of our results is to extract high amount and good quality prodigiosin for commercial application.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The chiral separation of etoxazole enantiomers on Lux Cellulose-1, Lux Cellulose-3, Chiralpak IC, and Chiralpak AD chiral columns was carefully investigated by normal-phase high performance liquid ...chromatography and reverse-phase high performance liquid chromatography (HPLC). Hexane/isopropanol, hexane/
-butanol, methanol/water, and acetonitrile/water were used as mobile phase at a flow rate of 0.8 mL/min. The effects of chiral stationary phase, mobile phase component, mobile phase ratio, and temperature on etoxazole separation were also studied. Etoxazole enantiomers were baseline separated on Lux Cellulose-1, Chiralpak IC, and Chiralpak AD chiral columns, and partially separated on Lux Cellulose-3 chiral column under normal-phase HPLC. However, the complete separation on Lux Cellulose-1, Chiralpak IC, and partial separation on Chiralpak AD were obtained under reverse-phase HPLC. Normal-phase HPLC presented better resolution for etoxazole enantiomers than reverse-phase HPLC. Thermodynamic parameters, including Δ
and Δ
, were also calculated based on column temperature changes from 10 °C to 40 °C, and the maximum resolutions (
) were not always acquired at the lowest temperature. Furthermore, the optimized method was successfully applied to determine etoxazole enantiomers in cucumber, cabbage, tomato, and soil. The results of chiral separation efficiency of etoxazole enantiomers under normal-phase and reverse-phase HPLC were compared, and contribute to the comprehensive environmental risk assessment of etoxazole at the enantiomer level.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Blocking the interaction of the immune checkpoint molecule programmed cell death protein-1 and its ligand, PD-L1, using specific antibodies has been a major breakthrough for immune oncology. ...Whole-body PD-L1 expression PET imaging may potentially allow for a better prediction of response to programmed cell death protein-1–targeted therapies. Imaging of PD-L1 expression is feasible by PET with the adnectin protein 18F-BMS-986192. However, radiofluorination of proteins such as BMS-986192 remains complex and labeling yields are low. The goal of this study was therefore the development and preclinical evaluation of a 68Ga-labeled adnectin protein (68Ga-BMS-986192) to facilitate clinical trials. Methods: 68Ga labeling of DOTA-conjugated adnectin (BXA-206362) was performed in NaOAc-buffer at pH 5.5 (50°C, 15 min). In vitro stability in human serum at 37°C was analyzed using radio-thin layer chromatography and radio-high-performance liquid chromatography. PD-L1 binding assays were performed using the transduced PD-L1–expressing lymphoma cell line U-698-M and wild-type U-698-M cells as a negative control. Immunohistochemical staining studies, biodistribution studies, and small-animal PET studies of 68Ga-BMS-986192 were performed using PD-L1–positive and PD-L1–negative U-698-M–bearing NSG mice. Results: 68Ga-BMS-986192 was obtained with quantitative radiochemical yields of more than 97% and with high radiochemical purity. In vitro stability in human serum was at least 95% after 4 h of incubation. High and specific binding of 68Ga-BMS-986192 to human PD-L1–expressing cancer cells was confirmed, which closely correlates with the respective PD-L1 expression level determined by flow cytometry and immunohistochemistry staining. In vivo, 68Ga-BMS-986192 uptake was high at 1 h after injection in PD-L1–positive tumors (9.0 ± 2.1 percentage injected dose %ID/g) and kidneys (56.9 ± 9.2 %ID/g), with negligible uptake in other tissues. PD-L1–negative tumors demonstrated only background uptake of radioactivity (0.6 ± 0.1 %ID/g). Coinjection of an excess of unlabeled adnectin reduced tumor uptake of PD-L1 by more than 80%. Conclusion: 68Ga-BMS-986192 enables easy radiosynthesis and shows excellent in vitro and in vivo PD-L1–targeting characteristics. The high tumor uptake combined with low background accumulation at early imaging time points demonstrates the feasibility of 68Ga-BMS-986192 for imaging of PD-L1 expression in tumors and is encouraging for further clinical applications of PD-L1 ligands.
The analysis of chemical constituents in Chinese herbal medicines (CHMs) is a challenge because of numerous compounds with various polarities and functional groups. Liquid chromatography coupled with ...quadrupole time-of-flight (QTOF) mass spectrometry (LC/MS) is of particular interest in the analysis of herbal components. One of the main attributes of QTOF that makes it an attractive analytical technique is its accurate mass measurement for both precursor and product ions. For the separation of CHMs, comprehensive two-dimensional chromatography (LCxLC) provides much higher resolving power than traditional one-dimensional separation. Therefore, a LCxLC-QTOF-MS system was developed and applied to the analysis of flavonoids and iridoid glycosides in aqueous extracts of
Hedyotis diffusa (Rubiaceae)
. Shift gradient was applied in the two-dimensional separation in the LCxLC system to increase the orthogonality and effective peak distribution area of the analysis. Tentative identification of compounds was done by accurate mass interpretation and validation by UV spectrum. A clear classification of flavonol glycosides (FGs), acylated FGs, and iridoid glycosides (IGs) was shown in different regions of the LCxLC contour plot. In total, five FGs, four acylated FGs, and three IGs were tentatively identified. In addition, several novel flavonoids were found, which demonstrates that LCxLC-QTOF-MS detection also has great potential in herbal medicine analysis.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
German chamomile is one of the most effective herbal elements used in anti‐allergic products and as an antioxidant. Herein, the antioxidant activity of different extract fractions of German chamomile ...was initially evaluated using an off‐line 2,2‐diphenyl‐1‐picrylhydrazyl spectrophotometric assay. The ethyl acetate extract demonstrated the highest efficacy in scavenging free radicals. Based on this, a rapid screening and separation method using ultra‐high‐performance liquid chromatography combined with the 2,2‐diphenyl‐1‐picrylhydrazyl assay was implemented to identify antioxidants in the ethyl acetate fraction of German chamomile flowers. Ten potential radical scavengers were tentatively screened from German chamomile using a target‐guided isolating approach with off‐line two‐dimensional high‐speed countercurrent chromatography and the structures of the compounds were analyzed and identified. Ultimately, 10 radical scavengers were obtained from the ethyl acetate extract with a purity quotient exceeding 90%. The results demonstrated the effectiveness and reproducibility of this method for isolating potential antioxidants from complex mixtures in a targeted manner. This strategy can be applied to the target‐guided isolation of complex mixtures of natural products with broad K‐values and similar structures.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The chiral separation of various analytes (dichlorprop, mecoprop, ibuprofen, and ketoprofen) was demonstrated with different cyclodextrins as mobile phase additives in open‐tubular liquid ...chromatography using a stationary pseudophase semipermanent coating. The stable coating was prepared by a successive multiple ionic layer approach using poly(diallyldimethylammonium chloride), polystyrene sulfonate, and didodecyldimethyl ammonium bromide. Increasing concentrations (0–0.2 mM) of various native and derivatized cyclodextrins in 25 mM sodium tetraborate (pH 9.2) were investigated. Chiral separation was achieved for the four test analytes using 0.05–0.1 mM β‐cyclodextrin (resolution between 1.11 and 1.34), γ‐cyclodextrin (resolution between 0.78 and 1.27), carboxymethyl‐β‐cyclodextrin (resolution between 1.64 and 2.59), and 2‐hydroxypropyl‐β‐cyclodextrin (resolution between 0.71 and 1.76) with the highest resolutions obtained with 0.1 mM carboxymethyl‐β‐cyclodextrin. %RSD values were <10%. This is the first demonstration of chiral open‐tubular liquid chromatography using achiral chromatographic coatings and cyclodextrins as mobile phase additives.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The green husk is one of the major wastes produced during the walnut (Juglans regia L.) cultivation. However, the results presented in this article may contribute to extension of their usefulness as ...new and safe plant protection products. The results confirmed the activity of the walnut green husk extracts against plant (Alternaria alternata, Rhizoctonia solani, Botrytis cinerea, Fusarium culmorum, Phytophthora cactorum) and bee (Ascosphaera apis) pathogenic fungi, and showed that the extraction conditions differentiate the properties of the obtained isolates. The increase in the isolation temperature leads to a significant reduction in the antifungal activity of the extracts. The change of the extractant type modifies the resistance of individual fungi. The observed variations in the properties are consistent with the change of juglone content in these extracts. However, considering the juglone concentration provided 50% inhibition of the growth of individual mycelia, the observed differentiation of the antifungal properties of extracts should not be associated only with the juglone content. This observation, supported by the results obtained using gas chromatography coupled to mass spectrometry (GC-MS) and liquid chromatography coupled to mass spectrometry (LC-MS), suggests a synergistic effect of the other components on the antifungal activity of walnut green husk extracts.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The studies on natural compounds to diabetes mellitus treatment have been increasing in recent years. Research suggests that natural components can inhibit alpha-glucosidase activities, an important ...strategy in the management of blood glucose levels. In this work, for the first time in the literature, the compounds produced by
Ganoderma lipsiense
extracts were identified and evaluated on the inhibitory effect of these on alpha-glucosidase activity. Four phenolic compounds were identified by high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) to crude extract from
G. lipsiense
grown in red rice medium (RCE) and synthetic medium (SCE), being syringic acid identified in both extracts. Gas chromatography-mass spectrometry (GC-MS) analysis showed fatty acids and their derivatives, terpene, steroid, niacin, and nitrogen compounds to
SCE
, while
RCE
was rich in fatty acids and their derivatives. Both extracts demonstrated alpha-glucosidase inhibition (
RCE
IC
50
= 0.269 ± 8.25 mg mL
−1
;
SCE
IC
50
= 0.218 ± 9.67 mg mL
−1
), and the purified hexane fraction of
RCE
(
RHEX
) demonstrated the highest inhibition of enzyme (81.1%). Studies on kinetic inhibition showed competitive inhibition mode to
RCE
, while
SCE
showed uncompetitive inhibition mode. Although the inhibitory effects of
RCE
and
SCE
were satisfactory, the present findings identified some unpublished compounds to
G. lipsiense
in the literature with important therapeutic properties.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A nutty flavor is desirable in Cheddar cheese and is easily accepted by most Chinese consumers. Although compounds responsible for nutty flavor in cheeses have been documented, no final conclusions ...have been reached. In this study, nine samples of top‐selling Cheddar cheeses in the Chinese market were selected, and the odor‐active compounds responsible for the nutty flavor in these samples were studied by gas chromatography‐mass spectrometry (GC‐MS), gas chromatography‐olfactometry (GC‐O), sensory evaluation, and aroma addition experiment. Forty‐nine volatile flavor compounds were identified by GC‐MS via headspace‐solid‐phase microextraction, and 14 odor‐active compounds were identified by GC‐O. It was determined that 2‐methylbutanal, 3‐methylbutanal, and benzaldehyde contributed to the nutty flavor of Cheddar cheese, according to Chinese tastes. The addition of suitable concentrations of these compounds to a model of Cheddar cheese without nutty flavor resulted in the perception of nutty aroma by sensory analysis. These results indicate that 2‐methylbutanal, 3‐methylbutanal, and benzaldehyde are the key aroma‐active compounds, which could make positive contributions to the nutty flavor of Cheddar cheese and favored by Chinese consumers within a certain concentration range.
In this study, nine samples of top‐selling Cheddar cheeses in the Chinese market were selected, and the odor‐active compounds responsible for the nutty flavor in these samples were studied by gas chromatography‐mass spectrometry (GC‐MS), gas chromatography‐olfactometry (GC‐O), sensory evaluation, and aroma addition experiment. 2‐methylbutanal, 3‐methylbutanal, and benzaldehyde are the key aroma‐active compounds, which could make positive contributions to the nutty flavor of Cheddar cheese and favored by Chinese consumers within a certain concentration range.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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