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Glycosylation is a predominant strategy plants use to fine-tune the properties of small molecule metabolites to affect their bioactivity, transport, and storage. It is also important in biotechnology and medicine as many glycosides are utilized in human health. Small molecule glycosylation is largely carried out by family 1 glycosyltransferases. Here, we report a structural and biochemical investigation of UGT95A1, a family 1 GT enzyme from Pilosella officinarum that exhibits a strong, unusual regiospecificity for the 3'-O position of flavonoid acceptor substrate luteolin. We obtained an apo crystal structure to help drive the analyses of a series of binding site mutants, revealing that while most residues are tolerant to mutations, key residues M145 and D464 are important for overall glycosylation activity. Interestingly, E347 is crucial for maintaining the strong preference for 3'-O glycosylation, while R462 can be mutated to increase regioselectivity. The structural determinants of regioselectivity were further confirmed in homologous enzymes. Our study also suggests that the enzyme contains large, highly dynamic, disordered regions. We showed that while most disordered regions of the protein have little to no implication in catalysis, the disordered regions conserved among investigated homologs are important to both the overall efficiency and regiospecificity of the enzyme. This report represents a comprehensive in-depth analysis of a family 1 GT enzyme with a unique substrate regiospecificity and may provide a basis for enzyme functional prediction and engineering.

Flexible Substrataufnahme aus Nährstoffreservoirs ist für Mikroorganismen entscheidend, um sich in kompetitiven natürlichen Umgebungen durchzusetzen. Zur Aufnahme von Glucose aus verschiedenen Glucosid‐ und Disaccharid‐Substraten haben viele frei‐ und symbiotisch lebende Bakterien, neben der Hydrolyse, einen nicht‐hydrolytischen Stoffwechselweg entwickelt. Dieser besteht aus vier biochemischen Schritten und wird von einem distinkten Genlocus (glycoside utilization locus, GUL) codiert. Mechanistisch integriert der Stoffwechselweg die Oxidation und Reduktion am Glucosyl/Glucose‐C3 mit der eliminativen Spaltung der glycosidischen Bindung und der Addition von Wasser an das Eliminationsprodukt in zwei aufeinanderfolgenden, von Lyasen katalysierten Reaktionen. In dieser Studie zeigen wir, basierend auf der Untersuchung von Enzymen des Pflanzenpathogens Agrobacterium tumefaciens, ein konserviertes Aktivitätszentrum in beiden Lyasen, welches um ein zentrales Mn2+ Metallion angeordnet ist. Weiters identifizieren wir die strukturellen Voraussetzungen für die spezifische Katalyse der 3‐Ketoglucosid Eliminierung zu 2‐Hydroxy‐3‐ketoglycal und der Hydratisierung des Glycal zu 3‐Ketoglucose. Die Erweiterung unserer Suche nach GUL‐codierten putativen Lyasen auf das menschliche darmkommensale Bakterium Bacteroides thetaiotaomicron führte uns zur Entdeckung eines Ca2+‐koordinierten Aktivitätszentrums in einem Glycosidase‐ähnlichen Protein. Das Enzym katalysiert die eliminative Spaltung von 3‐Ketoglucosiden entgegengesetzter (α) anomerer Konfiguration im Vergleich zu den von der A. tumefaciens Lyase präferierten Substraten (β). Strukturelle und biochemische Vergleiche zeigen die molekular‐mechanistische Basis der Stereokomplementarität der beiden 3‐Ketoglucosid Lyasen. Unsere Ergebnisse identifizieren ein grundlegendes Set von GUL‐codierten Lyasen für den Glucosidmetabolismus und erlauben es, der Gendiversität von GULs in der Domäne von Bakterien physiologische Bedeutung zuzuschreiben. [ABSTRACT FROM AUTHOR]

The experiment investigated the effects of different levels of zinc oxide nanoparticles (ZnONPs) (0, 10, 20, and 30 mg/L) and iron sulfate (13.9, 27.8, and 55.6 mg/L) on morphological and physiological responses of Stevia rebaudiana Bertoni plant under in vitro conditions. Results indicated that the combined application of ZnONPs at 10 mg and iron at 27.8 mg led to the highest increase in shoot number, height, and biomass, showing a respective rise of 17.37%, 39.66%, and 45.02% compared to control cultures. The highest pigment content and tissue antioxidant activity (83.48%) was observed with the combined presence of 10 mg/L ZnONPs and 27.8 mg/L iron. As ZnONP concentration increased in the culture medium, the combined effect on lipid peroxidation rate became more pronounced. The impact of ZnONPs on phenolic compound production varied depending on the specific substance. The iron content of shoots increased significantly by 41.11% under the influence of 27.8 mg/L iron and 10 mg/L ZnONP compared to control cultures. Interaction effects of treatments at various levels resulted in increased zinc content in shoots, peaking at 27.8 mg/L iron when ZnONP reached 20 mg/L, representing a 56.28% increment over control levels before slightly decreasing. The most increases in stevioside and rebaudioside were observed with the combination of 10 mg/L ZnONP and 27.8 mg/L iron, showing enhancements of 75.04% and 63.08%, respectively. These findings suggest that ZnONPs could stimulate the growth and enhance the bioactive components of stevia plants, making them a viable option as elicitors in in vitro batch cultures.Key messages: The combination of zinc oxide nanoparticles and iron in stevia tissue culture influenced growth, nutrition, and secondary metabolite production, suggesting their potential for inducing metabolite yields. [ABSTRACT FROM AUTHOR]

BACKGROUND: Targeted therapy based on nuclear transcription factor kappa B signaling pathway to explore neuroinflammation is increasingly worth exploring, and the advantages of Chinese medicine such as many targets, wide range, rich mechanisms, and few side effects have great potential in the treatment of various diseases. OBJECTIVE: Based on the nuclear transcription factor kappa B signaling pathway, this paper systematically expounded and summarized the research progress of kaempferol, safflower yellow, baicalin, and triptolide in the treatment of neuroinflammation after spinal cord injury. METHODS: Search terms “spinal cord injury, inflammation, anti-inflammatory, traditional Chinese medicine monomer, monomeric compound, NF-κB signaling pathway, flavonoids, glycosides, phenols, esters, alkaloids” were searched in CNKI and PubMed databases. Totally 67 articles were finally included. RESULTS AND CONCLUSION: (1) The role of nuclear transcription factor kappa B signaling pathway in the nervous system is complex and diverse, which can regulate neutrophils, microglia, astrocytes, and macrophages, and mediate the occurrence and development of inflammation after injury. (2) The effects of traditional Chinese medicine monomers such as baicalin on the degradation of nuclear transcription factor kappa B inhibitory protein, the inhibition of phosphorylation process by safflowerin on nuclear transcription factor kappa B signaling pathway, and the inhibition of kaempferol on nuclear transcription factor kappa B signaling pathway p65 nuclear translocation can reduce the impact of inflammatory response on the body, thereby promoting the recovery of neurological function. (3) The nuclear transcription factor kappa B signaling pathway can promote inflammation and immune cell migration and activation in the early stage of injury, and can promote the repair of injury site and the occurrence of fibrosis in the middle and late stages of injury. Appropriate activation of the nuclear transcription factor kappa B signaling pathway can promote the release of inflammatory factors, improve the antioxidant capacity of cells, and promote the activation of immune cells, but the over-activated nuclear transcription factor kappa B signaling pathway can easily lead to the occurrence and continuation of chronic inflammation and the inhibition of apoptosis. (4) Future research can further explore how to accurately regulate the activation level of nuclear transcription factor kappa B signaling pathway, how to achieve precise intervention for nervous system inflammation and injury, and can also focus on the preparation of traditional Chinese medicine monomers and the mechanism of action of traditional Chinese medicine monomers on signaling pathways, in order to provide more effective treatment strategies for the rehabilitation and functional recovery of neurological diseases. [ABSTRACT FROM AUTHOR]

Three new monosulfated polyhydroxysteroid glycosides, spiculiferosides A (1), B (2), and C (3), along with new related unsulfated monoglycoside, spiculiferoside D (4), were isolated from an ethanolic extract of the starfish Henricia leviuscula spiculifera collected in the Sea of Okhotsk. Compounds 1–3 contain two carbohydrate moieties, one of which is attached to C-3 of the steroid tetracyclic core, whereas another is located at C-24 of the side chain of aglycon. Two glycosides (2, 3) are biosides, and one glycoside (1), unlike them, includes three monosaccharide residues. Such type triosides are a rare group of polar steroids of sea stars. In addition, the 5-substituted 3-OSO3-α-L-Araf unit was found in steroid glycosides from starfish for the first time. Cell viability analysis showed that 1–3 (at concentrations up to 100 μM) had negligible cytotoxicity against human embryonic kidney HEK293, melanoma SK-MEL-28, breast cancer MDA-MB-231, and colorectal carcinoma HCT 116 cells. These compounds significantly inhibited proliferation and colony formation in HCT 116 cells at non-toxic concentrations, with compound 3 having the greatest effect. Compound 3 exerted anti-proliferative effects on HCT 116 cells through the induction of dose-dependent cell cycle arrest at the G2/M phase, regulation of expression of cell cycle proteins CDK2, CDK4, cyclin D1, p21, and inhibition of phosphorylation of protein kinases c-Raf, MEK1/2, ERK1/2 of the MAPK/ERK1/2 pathway. [ABSTRACT FROM AUTHOR]

This article provides detailed information about the threat of healthcare-acquired infections, specifically those caused by the Acinetobacter baumannii bacteria. It focuses on the O-polysaccharides of A. baumannii and their role in the bacteria's virulence. The article presents a chemical synthesis strategy for the hexa- and pentasaccharide repeating units of the O-7 and O-10 antigens of A. baumannii. It describes the synthesis process, purification, and characterization of several compounds, providing valuable information for researchers studying these compounds. The article also mentions the availability of supporting information online. [Extracted from the article]

One new aliphatic alcohol glycoside (1), together with eight known compounds (2-9) were isolated from the whole plant of Lomatogonium rotatum (L.) Fr. Their structures were established from spectroscopic data (1D, 2D NMR, and HR-ESI-MS) and comparison with the literature. Among them, compounds 2, 3 and 8, 9 were reported from the Gentianaceae family for the first time, compounds 4–7 had not been reported previously from the genus Lomatogonium. [ABSTRACT FROM AUTHOR]

This article discusses the development of a chemical synthesis strategy for the hexasaccharide repeating unit of the capsular polysaccharide of Streptococcus pneumoniae type 7A. The synthesis was achieved using a block synthetic strategy with minimal functional group modifications. The reactions were monitored by TLC and the products were characterized using NMR spectroscopy. The text provides detailed information about the synthesis and characterization of three compounds. The compounds mentioned in the text are complex and have multiple functional groups. The text provides information about the synthesis and characterization of a compound, including details about the chemical structure, NMR spectra, and HRMS data. The authors acknowledge the funding support they received for their research. [Extracted from the article]

This article discusses the synthesis of a hexasaccharide repeating unit found in the cell wall of Providencia alcalifaciens, a bacteria responsible for urinary tract infections and diarrheal diseases. The development of glycoconjugate-based therapeutics using this hexasaccharide could be useful in controlling these infections. The article presents a synthetic strategy for the preparation of the hexasaccharide, involving regio-selective glycosylation and the use of specific glycosylation promoters. The synthesis of various intermediates and their subsequent glycosylation steps are described in detail. The text also provides information about the synthesis and characterization of several compounds, including their yields and physical properties. Additionally, the text mentions the availability of supporting information, such as NMR spectra of the compounds. [Extracted from the article]

This article discusses the importance of developing strategies to prevent and treat infections caused by the opportunistic bacterium Acinetobacter baumannii (A. baumannii), which is responsible for various hospital-acquired infections. The article suggests that vaccination or immunotherapy could be a potential alternative strategy to combat A. baumannii infections. The focus of the study is on the chemical synthesis of the octasaccharide repeating unit of the capsular polysaccharide (CPS) K55 of A. baumannii BAL_204 strain, which could be used for the development of glycoconjugate vaccine candidates. [Extracted from the article]

This article discusses the synthesis of a specific compound found in the cell wall of a pathogenic bacteria called Escherichia coli. The compound is important for the bacteria's interaction with the human body and could potentially be used in the development of vaccines. The article provides detailed information about the synthesis process and the analysis of the compound. This information may be useful for researchers studying organic chemistry or working on antibacterial vaccines. [Extracted from the article]

One new iridoid glucoside, 7- O - E -feruloylgardoside (1) and two new lignan glycosides, 8′-hydroxyphillyrin (2) and 6''-(p -hydroxybenzyl) phillyrin (3), together with three known compounds, khainaoside B (4), phillyrin (5), and lantibeside (6), were isolated from the whole plants of Lancea tibetica. Their structures were elucidated on the basis of spectroscopic methods and X-ray crystallographic analysis. A DPPH free radical scavenging assay showed that 1 and 4 exhibited moderate antioxidant activity (IC 50 45.05 ± 3.04 and 48.00 ± 3.29 μ g/ml) compared with vitamin C (IC 50 3.31 ± 0.16 μ g/ml). [Display omitted] • One new iridoid glucoside (1) was isolated from Lancea tibetica. • Two new lignan glycosides (2 and 3) were isolated from Lancea tibetica. • Two iridoid glucosides (1 and 4) exhibited moderate antioxidant activity. [ABSTRACT FROM AUTHOR]

The need to explore the abundance of natural products cannot be overemphasized particularly in the management of various disease conditions. In traditional medical practice, Vernonia amygdalina has been widely adopted in the management of various inflammatory disorders. The objective of this investigation was to isolate the bioactive principles from the stem-bark and root of V. amygdalina and assess the anti-inflammatory (in vitro) activity of both the crude extracts and the isolated compounds. Following extraction with the methanol, the extract was subjected to gravity column chromatography and the resultant fractions was further purified to obtained pure compounds. The structural elucidation of the compounds were based on data obtained from 1H to 13C nuclear magnetic resonance (NMR) spectroscopies as well as fourier transform infrared (FT-IR). Using diclofenac as a control drug, the albumin denaturation assay was used to determine the in vitro anti-inflammatory activity of the extracts and isolates. Three distinct compounds characterized are vernoamyoside D, luteolin-7-α-o-glucuronide, and vernotolaside, a new glycoside. When compared to diclofenac, which has an IC50 of 167.8 μg/mL, luteolin-7-α-o-glucuronide, vernoamyoside D, and vernotolaside all showed significant inhibitions with respective IC50 values 549.8, 379.5, and 201.7 μg/mL. Vernotolaside is reported for the first time from the root. The assertion that the plant is used in traditional medicine for the management of inflammatory disorder is somewhat validated by the confirmation of the existence of the compounds with the biochemical actions. Further validation of the isolated compounds would be required in animal studies.

Three new monosulfated polyhydroxysteroid glycosides, spiculiferosides A (1), B (2), and C (3), along with new related unsulfated monoglycoside, spiculiferoside D (4), were isolated from an ethanolic extract of the starfish Henricia leviuscula spiculifera collected in the Sea of Okhotsk. Compounds 1–3 contain two carbohydrate moieties, one of which is attached to C-3 of the steroid tetracyclic core, whereas another is located at C-24 of the side chain of aglycon. Two glycosides (2, 3) are biosides, and one glycoside (1), unlike them, includes three monosaccharide residues. Such type triosides are a rare group of polar steroids of sea stars. In addition, the 5-substituted 3-OSO3-α-L-Araf unit was found in steroid glycosides from starfish for the first time. Cell viability analysis showed that 1–3 (at concentrations up to 100 μM) had negligible cytotoxicity against human embryonic kidney HEK293, melanoma SK-MEL-28, breast cancer MDA-MB-231, and colorectal carcinoma HCT 116 cells. These compounds significantly inhibited proliferation and colony formation in HCT 116 cells at non-toxic concentrations, with compound 3 having the greatest effect. Compound 3 exerted anti-proliferative effects on HCT 116 cells through the induction of dose-dependent cell cycle arrest at the G2/M phase, regulation of expression of cell cycle proteins CDK2, CDK4, cyclin D1, p21, and inhibition of phosphorylation of protein kinases c-Raf, MEK1/2, ERK1/2 of the MAPK/ERK1/2 pathway.

Computational studies of cyanidin and peonidin, and related anthocyanin: cyanidin-3-O glucoside (cya-3-O-glu) and peonidin-3-O glucoside (peo-3-O-glu) were performed to identify the dye potential in order to use in dye-sensitized solar cells (DSSCs). B3LYP/6-31+G(d, p) level of theory was used for ground state optimization and chemical properties estimation of the dyes. The absorption spectra, excited states, and optical parameters were obtained using TDDFT with the same functional and basis set. The dyes properties in water and ethanol as solvent were evaluated at the same level of theory for ground and excited states. The results have shown that the studied dyes, under the effects of solvents, can be used in DSCCs but not in the gas phase. Water and ethanol have the same effect on the chemical properties and absorption spectrum of the dyes. The hardness and ionization potential of peonidin have the lowest value. Also, light harvesting efficiency of it has the highest value. Electron injection from photoexcited dye to the conduction band of the semiconductor was done spontaneously with a negative value of ΔGinject as free energy change of electron inject process in order peo-3-O-glu < peo < cya-3-O-glu < cya. Therefore, all the studied dyes are suitable for application in DSSC technology, but peonidin and its glycoside form have higher efficiency. [ABSTRACT FROM AUTHOR]

The synergy between Na+-K+ pumps, Na+-Ca2+ exchangers, membrane currents and the sarcoplasmic reticulum (SR) generates the coupled-clock system, which governs the spontaneous electrical activity of heart sinoatrial node cells (SANCs). Ca2+ mediates the degree of clock coupling via local Ca2+ release (LCR) from the SR and activation of cAMP/PKA signaling. Marinobufagenin (MBG) is a natural Na+-K+ pump inhibitor whose effect on SANCs has not been measured before. The following two hypotheses were tested to determine if and how MBG mediates between the Na+-K+ pump and spontaneous SAN activity: (i) MBG has a distinct effect on beat interval (BI) due to variable effects on LCR characteristics, and (ii) Ca2+ is an important mediator between MBG and SANC activity. Ca2+ transients were measured by confocal microscopy during application of increasing concentrations of MBG. To further support the hypothesis that Ca2+ mediates between MBG and SANC activity, Ca2+ was chelated by the addition of BAPTA. Dose response tests found that 100 nM MBG led to no change in BI in 6 SANCs (no BI change group), and to BI prolongation in 10 SANCs (BI change group). At the same concentration, the LCR period was prolonged in both groups, but more significantly in the BI change group. BAPTA-AM prolonged the BI in 12 SANCs. In the presence of BAPTA, 100 nM MBG had no effect on SANC BI or on the LCR period. In conclusion, the MBG effects on SANC function are mediated by the coupled clock system, and Ca2+ is an important regulator of these effects. [ABSTRACT FROM AUTHOR]

A new glycoside, recurvataside (1) and six known compounds, quinovic acid (2), quinovic acid 28-O-β-D-glucopyranosyl ester (3), 3-O-β-D-glucopyranosylquinovic acid (4), 3-O-β-D-glucopyranosylquinovic acid 28-O-β-D-glucopyranosyl ester (5), pomolic acid (6), and ursolic acid (7) were isolated from aerial parts of Mussaenda recurvata. The structure of compound 1 was identified from its spectroscopic data and by comparison with the literature. Recurvataside represents the first occurrence of δ-oleanolic acid saponin bearing two D-glucose units at C-3 and C-28 in nature. This is the first time δ-oleanane-type saponin reported in the genus Mussaenda. Compounds 1-7 were evaluated the cytotoxicity against two cancer cell lines MCF-7 and HepG2. Among them, only compound 7 exhibited moderate activity against MCF-7 and HepG2 cell lines with IC50 value of 16.97 ± 1.55 and 20.28 ± 1.00 μM, respectively. Compounds 1–7 were also tested for their inhibitory NO production in LPS-stimulated RAW264.7 cells. Compounds 3, 5, and 7 showed significant reduction of nitrite accumulation in LPS-stimulated RAW 264.7 cells with the IC50 values of 8.81 ± 0.48, 13.42 ± 0.84, and 18.37 ± 0.67 μM, respectively. [ABSTRACT FROM AUTHOR]

Pathogenic de novo variants in the X-linked gene SLC35A2 encoding the major Golgi-localized UDP-galactose transporter required for proper protein and lipid glycosylation cause a rare type of congenital disorder of glycosylation known as SLC35A2-congenital disorders of glycosylation (CDG; formerly CDG-IIm). To date, 29 unique de novo variants from 32 unrelated individuals have been described in the literature. The majority of affected individuals are primarily characterized by varying degrees of neurological impairments with or without skeletal abnormalities. Surprisingly, most affected individuals do not show abnormalities in serum transferrin N-glycosylation, a common biomarker for most types of CDG. Here we present data characterizing 30 individuals and add 26 new variants, the single largest study involving SLC35A2-CDG. The great majority of these individuals had normal transferrin glycosylation. In addition, expanding the molecular and clinical spectrum of this rare disorder, we developed a robust and reliable biochemical assay to assess SLC35A2-dependent UDP-galactose transport activity in primary fibroblasts. Finally, we show that transport activity is directly correlated to the ratio of wild-type to mutant alleles in fibroblasts from affected individuals.

Low molecular weight organogelators provide useful materials which have already found applications in various fields. Recently, phenylboronate alkylglucosides have become new members of this type of organogelators providing water‐sensitive gels. This work is focused on the impact of the position of alkyl and phenyl moieties within this type of structures. Thus, alkylboronate phenylglucoside and alkylboronate alkylglucoside counterparts were synthesized and studied. Organogels obtained in toluene and ethyl myristate were characterized by rheology and electron microscopy. In addition, we also determined the disruption rates of such organogels upon addition of a small amount of water. Alkylboronate alkylglucosides did not induce gelation of the tested solvents but all derivatives bearing a phenyl ring either on the boronate function or on the glucoside unit came out as good organogelators. However, alkylboronates were found to have higher water sensitivities than phenyl counterparts. Thus, this work has enlarged the scope of glucoside‐boronate organogelators and their water sensitivity which can represent useful materials in drug delivery systems for example. [ABSTRACT FROM AUTHOR]

Spiraea hypericifolia L. is affiliated with the section Chamaedryon Ser. of the genus Spiraea L. (Rosaceae). Similar to many other Spiraea species, S. hypericifolia most often accumulates flavonols among other flavonoids, in particular quercetin and its derivatives. An ethanol–water extract from the aerial part of S. hypericifolia collected in the vicinity of the Ilyichovo settlement (Krasnoyarsk Krai, Russia) was analyzed by liquid chromatography with high-resolution mass spectrometry. Primary and secondary metabolites were found in the extract; structural interpretation consistent with quercetin and its derivatives was proposed for 10 of them. Major compounds were various glycosides of quercetin containing glucose (four compounds), galactose (one compound), xylose (two compounds), arabinose (one compound), or rutinose (one compound) as a carbohydrate residue. Isorhamnetin and 3-O-methylquercetin-3′-O-β-D-glucopyranoside were identified among methyl-containing compounds. The latter compound and reynoutrin, rhamnetin-3-O-β-D-xylopyranosyl-β-D-glucopyranoside, and quercetin-3-O-(6″-O-malonyl)-β-D-glucoside have not been previously found in S. hypericifolia. Data on the presence of quercetin and its derivatives in the extract of S. hypericifolia expand the understanding of the possible practical use of this plant. In addition, the microscopic features of S. hypericifolia leaves were studied. The diagnostic features of the leaf blade necessary for the authentication of raw materials were revealed: straight-walled epidermis cells, stomata located on both sides of the leaf blade (amphistomatic type), two types of trichomes, and wrinkled cuticula with nodi. The main anatomical diagnostic features of the leaves of S. hypericifolia were determined, which makes it possible to assess the authenticity of the raw material. [ABSTRACT FROM AUTHOR]

In this study, some novel mono- and di-O-β-D-glycopyranosyl chalcone analogs were designed, synthesized, and characterized. The chalcone derivatives were synthesized with good yields by base-catalyzed Claisen-Schmidt condensation in EtOH solution. Then these chalcones were reacted with TAGBr (2,3,4,6-tetra-O-acetyl-α-D-glucopyranosylbromide) in dry acetone under the anhydrous condition at 0–5 °C. Deacylated was carried out by the Zemplen’s method with NaOCH3 in dry methanol results in substituted chalconeO-glycosides (mono- and di-O-β-D-glycopyranosyl chalcone analogs). The chemical structures of all synthesized compounds were elucidated based on IR, NMR spectral data, and mass spectrometry. Further, the compounds (7a-c, 8a-c, 12a-c, 16a-c, and 17a-c) were tested for their enzyme inhibition activity against α-glycosidase, tyrosinase, and AChE with in vitro and in silico analysis. Amongst them, compounds 12a-c, 16a-c, and 17a-c displayed moderate or less enzyme inhibition activity against α-glycosidase while other compounds 7a-c and 8a-c) were not active. Remarkably interesting enzyme inhibition effects, with IC50 values below 30.59 ± 0.30 µM were recorded with 7c (IC50=11.07 ± 0.55 µM) against tyrosinase. [ABSTRACT FROM AUTHOR]

Glycosylation of 2-oxo(sulfanylidene)-3-phenyl-6-[4-(propan-2-yl)phenyl]pyrimidine-5-carbo-nitritles with glucosyl and galactosyl bromides in the presence of potassium hydroxide afforded mixtures of N- and O- or N- and S-glycosides which were deacetylated with triethylamine to give the corresponding free nucleosides. Alkylation of the same pyrimidinecarbonitriles with 3-chloropropan-1-ol and epichlorohydrin yielded N- and S-derivatives. The structure of the new compounds was established using spectral data. Some of the synthesized compounds showed moderate activity against gram-positive and gram-negative bacteria and fungi. [ABSTRACT FROM AUTHOR]

Fucosylation is one of the most common modifications of oligo‐N‐acetyllactosamine (oligo‐LacNAc) glycans. However, none of known fucosyltransferases (FucTs) could install the α1,3‐linked fucose to the oligo‐LacNAc substrates in a site‐specific manner. Here, we report a facile and general redox‐controlled substrate engineering strategy for the site‐specific α1,3‐fucosylation of complex glycans containing multiple LacNAc units. This strategy takes advantage of an operationally simple oxidation enzyme module by using galactose oxidase (GOase) to convert the LacNAc unit into oxidized C6′‐aldehyde LacNAc sequence, which is not a good substrate for recombinant α1,3‐FucT from Helicobacter pylori strain 26695 (Hpα1,3FucT), enabling the site‐specific α1,3‐fucosylation at intact LacNAc sites. The general applicability and robustness of this strategy were demonstrated by the synthesis of a variety of structurally well‐defined fucosides of linear and branched O‐ and N‐linked glycans. [ABSTRACT FROM AUTHOR]

Repeated column chromatography resulted in the isolation of two new glycosides, miliusides A–B (1 and 7), along with six known metabolites (2–6, and 8) from the leaves of Miliusa sinensis Finet and Gagnep. The structures of the purified phytochemicals were elucidated by interpreting their spectroscopic data (NMR, HRMS), as well as comparison with the previous literature. The biological evaluation of acetylcholinesterase (AChE) inhibitory effects and anti-inflammatory activity by measuring nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophage cells, were also conducted. Among them, compounds 5 and 7 exhibited significant AChE inhibitory activities (IC50 = 53.36 ± 4.20 and 88.50 ± 8.79 µM, respectively), compared with the positive control (Galanthamine, IC50 = 1.65 ± 0.15 µM). Only the MeOH extract showed suppression effects on NO production in LPS-induced RAW264.7 cells (IC50 = 38.18 ± 3.25 μg/mL) comparable to that of the positive control, l-NMMA (IC50 = 2.21 ± 0.56 μg/mL). [ABSTRACT FROM AUTHOR]

Terpenes, one of the secondary metabolites produced by plants, have diverse physiological functions. They are volatile compounds with physiological bioactivities (e.g., insect repellent, attracting enemies, and interacting with other plants). Terpenoids are also essential for flavor and aroma in plant-derived foods. In coffee, its aroma decides the value of coffee beans. Linalool, one of the volatile terpene compounds, is dominant in the coffee aroma. Coffee, with its good flavor and aroma, has high demand worldwide. Because terpenoids generally accumulate as glycosides in plant cells, glycosylation is catalyzed by UDP-glycosyltransferases (UGTs). Two linalyl-diglycosides have been identified: terpenoids reflected as necessary for coffee flavor. However, these UGTs and their action mechanisms are unknown in the Coffea genus. To obtain knowledge of terpene UGTs and elucidate the mechanism of terpene glycosylation in coffee, this study isolated terpene UGT genes and analyzed their functions. In silico screening based on the sequence of UGT85K11 , which catalyzes terpene glycosylation from Camellia sinensis , was performed to obtain sequence information on five candidate UGT genes (CaUGT4 , CaUGT5 , CaUGT10 , CaUGT15 , and CaUGT20). These genes were isolated by reverse transcription-polymerase chain reaction, and the recombinant enzymes were produced with the Escherichia coli expression system. In functional analysis using radioisotopes, CaUGT4 showed critical activity against linalool, which had a higher affinity for its substrate than that of UGT85A84 from Osmanthus fragrans. Liquid chromatography-tandem mass spectrometry also revealed that CaUGT4 mainly produces linalyl glucoside. In this study, the first linalyl UGT was isolated from coffee. These findings can be used to elucidate the fundamental mechanism of the chemical defense in plants and apply aroma precursors for the plant-derived food industry in the future. • In silico screening based on the terpene glycosyltransferase from tea was performed. • Linalyl UGTs were isolated from coffee and their functions were analyzed. • CaUGT4(UGT85A192) showed critical activity against linalool. [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids, 1–2, together with three known compounds, were isolated from Trichoderma hypoxylon. Among the known compounds, compound 4 was isolated as naturally occurring compound for the first time. The structures of these new compounds were characterized by HR-ESI-MS and spectroscopic methods including 1D and 2D NMR. The absolute configurations of 1–2 were assigned by electronic circular dichroism (ECD) calculations.

Background: Ceiba pentandra (L.) Gaertn, popularly known as the white silk-cotton tree and popularly used in Chinese and Indian traditional medicine. The bark is used to treat diarrhea, pain, fever, cardiac problems, asthma, and gastrointestinal problems. The present study aimed to evaluate the hepatoprotective and antioxidant effects of ethanol extract of C. pentandra bark (EECP-BK) against CCl4-induced hepatic damage in rats. Methods: Preliminary phytochemical analysis was performed to identify the bioactive compounds. CCl4 (40 mM) induced enzymatic changes at HepG2 cells were adopted for the in-vitro model. HepG2 cells were pretreated with EECP-BK (25, 50, 100, and 200 µg/ml) and standard (silymarin 12.5 µg/ml) respectively. Rat model of CCl4-induced liver damage for adopted for the in-vivo model. Rats were pretreated orally with EECP-BK 200 & 400 mg/kg and standard (silymarin 100 mg/kg) for 7 days. Rats were injected with 1 ml/kg of 50% CCl4 on day 8 to induce hepatic damage and were observed for antioxidant levels and serum biomarkers. In addition, in-silico studies have been performed to explore the binding properties of compounds from EECP-BK with tumor necrosis factor-alpha converting enzyme (TACE) targeting hepatic inflammation Results: The phytochemical analysis confirmed the presence of glycoside, steroids, phenols, tannins, and saponins. EECP-BK 200 µg/ml showed the highest protection against CCl4 in HepG2 cells. Similarly, silymarin 12.5 µg/ml showed good protection against CCl4. In rats, EECP-BK up to 2000 mg/kg did produce any toxic signs or mortality. CCl4 injection in rats showed elevated liver enzymatic and bilirubin levels and causes liver damage. It also decreased the SOD, CAT, and GSH levels. Pre-treatment with EECP-BK 400 mg/kg showed a significant reduction in SGPT, SGOT, ALP, and total bilirubin levels and increased SOD, CAT, and GSH levels. Similar results were observed with, silymarin treatment also. Furthermore, EECP-BK showed protection over hepatocyte necrosis induced by CCl4 in rats which is evident by histopathology. Molecular docking studies revealed that acacetin 7-rutinoside binds favorably with the active site of TACE with a binding affinity of -8.8 kJ/mol. Conclusion: Our findings supported the antioxidative capability of EECP-BK by showing that it protected the liver from CCl4-induced hepatic damage. Additional research is needed to determine its safety profile and to find its molecular mechanism for therapeutic application.

Bacteria belonging to the phylum Actinobacteria are a very good source of antibiotics, and indeed dominate the current clinical antibiotic space. This paper reports Mutactimycin AP, a new compound belonging to an anthracycline-type family of antibiotics, isolated from a Saccharothrix sp. This actinobacterial strain was isolated from the rhizosphere of lupine plants growing in the extreme hyper-arid Atacama Desert. Structural characterization was carried out using electrospray ionization-mass spectrometry (ESI-MS) and NMR spectroscopy in combination with molecular modelling. The compound was tested against the ESKAPE pathogens, where it showed activity against MRSA and five strains associated with bovine mastitis, where it showed activity against Enterococcus pseudoavium and Staphylycoccus Aureus subsp. Aureus. [ABSTRACT FROM AUTHOR]

Fruit plants produce various volatile compounds that emit distinct aroma characteristics and contribute to their flavor qualities. However, some of these substances, especially hydroxyl-group molecules, are in non-volatile glycosylated forms. This study aimed to determine free and glycosidically bound volatile compounds in three Okinawan pineapple cultivars ('N67-10′, 'Yugafu', and 'Yonekura'). The free volatile components of squashed pineapple juice were analyzed using solid-phase microextraction (SPME)–arrow-gas chromatography–flame ionization detection/mass spectrometry (GC-FID/MS). The glycosides were collected through solid-phase extraction, hydrolyzed by β-glucosidase, and the released volatile compounds were measured. The sugar moieties of the glycosides were confirmed using GC-MS, and their glycoside constituents were analyzed using liquid chromatography (LC)-MS. Okinawan pineapple varied in its content and composition of free volatile components, which were predominantly comprised of esters, followed by alcohols, terpenes, and ketones. Eight hydroxyl-group compounds, including chavicol, eugenol, geraniol, phenylethyl alcohol, benzyl alcohol, 2-ethyl-1-hexanol, 1-hexanol, and 3-methyl-2-butenol, were released from their glycosylated forms via enzymatic hydrolysis, wherein the amounts of most of them were greater in 'Yonekura' than in the other cultivars. Moreover, two glycosides, chavicol-O-β-D-glucopyranoside and eugenol-O-β-D-glucopyranoside, were identified in all the cultivars, wherein the aglycones of both glycosides could be potential odor sources of the medicinal-herbal aromas. These results provide important information regarding both volatile-aroma qualities and bounded-aroma resources in Okinawan pineapple for fresh consumption and agroindustrial processing. [ABSTRACT FROM AUTHOR]

A straightforward synthesis of the pentasaccharide with a readily available linker arm corresponding to the O-antigenic polysaccharide of Acinetobacter junii strain 65 has been achieved in good yield. The synthesis has been carried out using thioglycosides as glycosyl donor in the presence of a combination of N-iodosuccinimide (NIS) and trifluoromethanesulfonic acid (TfOH) as thiophilic activator. The yields of the glycosylation steps were very good with satisfactory stereochemistry at the glycosidic linkages. The pentasaccharide derivative has also been obtained using a one-pot iterative glycosylation strategy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The synergy between Na+-K+ pumps, Na+-Ca2+ exchangers, membrane currents and the sarcoplasmic reticulum (SR) generates the coupled-clock system, which governs the spontaneous electrical activity of heart sinoatrial node cells (SANCs). Ca2+ mediates the degree of clock coupling via local Ca2+ release (LCR) from the SR and activation of cAMP/PKA signaling. Marinobufagenin (MBG) is a natural Na+-K+ pump inhibitor whose effect on SANCs has not been measured before. The following two hypotheses were tested to determine if and how MBG mediates between the Na+-K+ pump and spontaneous SAN activity: (i) MBG has a distinct effect on beat interval (BI) due to variable effects on LCR characteristics, and (ii) Ca2+ is an important mediator between MBG and SANC activity. Ca2+ transients were measured by confocal microscopy during application of increasing concentrations of MBG. To further support the hypothesis that Ca2+ mediates between MBG and SANC activity, Ca2+ was chelated by the addition of BAPTA. Dose response tests found that 100 nM MBG led to no change in BI in 6 SANCs (no BI change group), and to BI prolongation in 10 SANCs (BI change group). At the same concentration, the LCR period was prolonged in both groups, but more significantly in the BI change group. BAPTA-AM prolonged the BI in 12 SANCs. In the presence of BAPTA, 100 nM MBG had no effect on SANC BI or on the LCR period. In conclusion, the MBG effects on SANC function are mediated by the coupled clock system, and Ca2+ is an important regulator of these effects.

Coffee volatile compounds formation has been studied for years and the main flavour precursors have been identified. Coffee glycosidically bound volatiles (GBVs) are still underexplored and, yet, can act as aroma precursors during the post-harvesting processing and roasting. Free volatile compounds and GBVs of green coffee beans (CB), roasted CB and spent coffee ground (SCG) were analysed. Roasting led to the formation of a new GBVs pool from green to roasted CB and SCG. Most of the GBVs of green CB were hydrolysed during roasting. On the other hand, pyrroles, cycloketones, pyridines and pyrans were identified for the first time as bound volatiles and occurred only after the roasting process. This study supports the importance of GBVs on coffee aroma formation during the post-harvest processing. The release of the GBVs of roasted CB during brewing could enhance the varietal aromas of industrial ready-to-drink coffees. Furthermore, the SCG GBVs could be used as a new source of natural flavours for perfume industries. [ABSTRACT FROM AUTHOR]

Two new glycosides, namely panalaside A (1) and panalaside B (2) were isolated from from Panzerina lanata (L.) Soják. The structures of 1 and 2 were elucidated by spectroscopic methods, including UV, IR, HR-ESI-MS and extensive 1 D and 2 D NMR techniques. [ABSTRACT FROM AUTHOR]

Natural products isolation studies of 16 native Australian fern species have been undertaken, facilitated by pressurised hot water extraction (PHWE). Fourteen of these fern species have not been the subject of natural products isolation research previously. In total, 14 different compounds were isolated from 12 of these 16 different fern species. This included γ - and δ -lactones; flavonoid glycosides, a dihydrobenzofuran neolignan, in addition to hydroxycinnamate/caffeic acid esters. More specifically, the lactones 5,6-dihydro-5-hydroxy-6-methyl- 2H -pyran-2-one, 5-(1-hydroxyethyl)-2(5H)-furanone and osmundalin were obtained from Todea barbara , while a dihydrobenzofuran neolignan, (−)- trans -blechnic acid were found in Austroblechnum penna-marina subsp. alpina , and the shikimate ester 5- O -caffeoylshikimic acid was isolated from Parablechnum wattsii. In addition, flavonoids and their glycoside derivatives, kaempferol 3- O -glucopyranoside, 4 β -carboxymethyl-(−)-epicatechin, (2R)-eriodictyol-7- O - β -d-glucopyranoside, naringin, quercitrin, quercetin 3- O -(6″-acetyl)- β -d-glucopyranoside, rutin, and tiliroside were isolated from seven other fern species. This work reports natural products isolation studies of 16 native Australian fern species, 14 of which have not been the subject of such research previously. In total, 14 different compounds were isolated from 12 of these 16 different fern species. [ABSTRACT FROM AUTHOR]

[Display omitted] • Acid hydrolysis converts glycosidic polyphenols to their aglycone form. • Acid hydrolysis increases the content of phenolic compounds. • Acid hydrolysis enhances the antioxidant activity of extracts. • Acid-hydrolysed extracts inhibit lipid oxidation in oil-in-water emulsions. The antioxidant activity of the natural phenolic extracts is limited in particular food systems due to the existence of phenolic compounds in glycoside form. Acid hydrolysis post-treatment could be a tool to convert the glycosidic polyphenols in the extracts to aglycones. Therefore, this research investigated the effects of an acid hydrolysis post-treatment on the composition and antioxidant activity of parsley extracts obtained by an ultrasound-assisted extraction method to delay lipid oxidation in a real food system (i.e., soybean oil-in-water emulsion). Acid hydrolysis conditions were varied to maximize total phenolic content (TPC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. When extracts were exposed to 0.6 M HCl for 2 h at 80 ℃, TPC was 716.92 ± 24.43 µmol gallic acid equivalent (GAE)/L, and DPPH radical scavenging activity was 66.89 ± 1.63 %. Not only did acid hydrolysis increase the concentrations of individual polyphenols, but it also resulted in the release of new phenolics such as myricetin and gallic acid. The extract's metal chelating and ferric-reducing activity increased significantly after acid hydrolysis. In soybean oil-in-water emulsion containing a TPC of 400 µmol GAE/L, the acid-hydrolyzed extract had an 11-day lag phase for headspace hexanal compared to the 6-day lag phase of unhydrolyzed extract. The findings indicated that the conversion of glycosidic polyphenols to aglycones in phenolic extracts can help extend the shelf-life of emulsion-based foods. [ABSTRACT FROM AUTHOR]

α-Nitrophenyl derivatives of glycosides are convenient substrates used to detect and characterize α-N-acetylgalactosaminidase. A new procedure combining chemical and biocatalytic steps was developed to prepare 4-nitrophenyl-2-acetamido-2-deoxy-α-D-galactopyranoside (4NP-α-GalNAc). The α-anomer was prepared through chemical synthesis of an anomeric mixture followed by selective removal of the β-anomer using specific enzymatic hydrolysis. Fungal β-N-acetylhexosaminidase (Hex) from Penicillium oxalicum CCF 1959 served this purpose owing to its high chemo-and regioselectivity towards the β-anomeric N-acetylgalactosamine (GalNAc) derivative. The kinetic measurements of the hydrolytic reaction showed that the enzyme was not inhibited by the substrate or reaction products. The immobilization of Hex in lens-shaped polyvinyl alcohol hydrogel capsules provided a biocatalyst with very good storage and operational stability. The immobilized Hex retained 97% of the initial activity after ten repeated uses and 90% of the initial activity after 18 months of storage at 4 °C. Immobilization inactivated 65% of the enzyme activity. However, the effectiveness factor and kinetic and mass transfer phenomena approached unity indicating negligible mass transfer limitations. [ABSTRACT FROM AUTHOR]

Fuscatin B (1), liriodenine, (–)-anonaine, northalifoline, thalifoline, p-hydroxybenzoic acid, p-hydroxybenzaldehyde, vanillic acid, isovanillic acid, β-sitosterol, stigmasterol, 11,13-dehydrolanuginolide, and costunolide were isolated from the unripe flowers of Michelia fuscata (Magnoliaceae). Among them, fuscatin B is a new glycoside (caffeic acid phenethyl ester 3-O-4′′-rhamnosyl-(1′′→3′′′)-glucoside). The structures of these compounds were characterized and identified by spectral analyses. [ABSTRACT FROM AUTHOR]

Four new triterpene glucosides (1–4) were isolated from the 90% ethanol extract of Salacia cochinchinensis, together with five known compounds (5–9). The structures of the new compounds were elucidated by comprehensive spectroscopic analysis including HRESIMS, IR, 1 D and 2 D NMR analysis. All isolates were assayed for their α-glucosidase inhibitory activity. Compound 9 showed remarkable α-glucosidase inhibitory activity with an IC50 value of 0.31 μM, and the triterpene glycosides (1–5) exhibited moderate α-glucosidase inhibitory activity. [ABSTRACT FROM AUTHOR]

Cdc25 phosphatases have been considered promising targets for anticancer development due to the correlation of their overexpression with a wide variety of cancers. In the last two decades, the interest in this subject has considerably increased and many publications have been launched concerning this issue. An overview is constructed based on data analysis of the results of the previous publications covering the years from 1992 to 2021. Thus, the main objective of the current review is to report the chemical structures of Cdc25s inhibitors and answer the question, how to design an inhibitor with better efficacy and lower toxicity? [ABSTRACT FROM AUTHOR]

Two new sesquiterpenoids, 1–2, together with three known compounds, were isolated from Trichoderma hypoxylon. Among the known compounds, compound 4 was isolated as naturally occurring compound for the first time. The structures of these new compounds were characterized by HR-ESI-MS and spectroscopic methods including 1D and 2D NMR. The absolute configurations of 1–2 were assigned by electronic circular dichroism (ECD) calculations. [ABSTRACT FROM AUTHOR]

Flavonoids are bioactive plant compounds that are widely present in the human diet. Estimating flavonoid intake with a high degree of certainty is challenging due to the inherent limitations of dietary questionnaires and food composition databases. This study aimed to evaluate the degree of reliability among flavonoid intakes estimated using four different approaches based on the two most comprehensive flavonoid databases, namely, United States Department of Agriculture (USDA) and Phenol Explorer (PE). In 678 individuals from the MAX study, a subcohort of the Diet, Cancer and Health-Next Generations cohort, dietary data were collected using three 24-h diet recalls over 1 year. Estimates of flavonoid intake were compared using flavonoid food content from PE as (1) aglycones (chromatography with hydrolysis), (2) aglycones transformed (converted from glycosides by chromatography without hydrolysis), (3) as they are in nature (glycosides, aglycones, and esters), and 4) using flavonoid content from USDA as aglycones (converted). Spearman's intra-class correlation (ICC) coefficient and weighted kappa (K) coefficient were calculated for the reliability analysis. When comparing PE total aglycones to USDA total aglycones, there was a moderate reliability when a continuous variable was used [ICC: 0.73, 95% confidence interval (CI): 0.70–0.76] and an excellent reliability when flavonoid intake was modeled as a categorical variable (K: 0.89, 95% CI: 0.88–0.90). The degree of reliability among all methods of estimated flavonoid intakes was very similar, especially between database pairs, for the flavanol subclass, while larger differences were observed for flavone, flavonol, and isoflavone subclasses. Our findings indicate that caution should be taken when comparing the results of the associations between flavonoid intakes and health outcomes from studies, when flavonoid intakes were estimated using different methods, particularly for some subclasses.

Syringa pubescens Turcz is commonly used folk medicinal herb in west of Henan Province of China. In this work, water and various concentration of methanol, ethanol and acetone in water were used as solvent to extract echinacoside and oleuropein from S. pubescens. The antioxidant properties of different extracts were evaluated using various in vitro assays. The highest yields of echinacoside and oleuropein were obtained by using the 60% aqueous methanol and 80% aqueous ethanol, respectively. The extracts of water, aqueous ethanol or methanol showed strong antioxidant abilities. Furthermore, the high correlation between echinacoside content and antioxidant properties was found. The contribution of oleuropein content was not significant to antioxidant abilities. These findings indicate that S. pubescens can be used as a new natural antioxidant resource [ABSTRACT FROM AUTHOR]

Spiraea hypericifolia L. is affiliated with the section Chamaedryon Ser. of the genus Spiraea L. (Rosaceae). Similar to many other Spiraea species, S. hypericifolia most often accumulates flavonols among other flavonoids, in particular quercetin and its derivatives. An ethanol–water extract from the aerial part of S. hypericifolia collected in the vicinity of the Ilyichovo settlement (Krasnoyarsk Krai, Russia) was analyzed by liquid chromatography with high-resolution mass spectrometry. Primary and secondary metabolites were found in the extract; structural interpretation consistent with quercetin and its derivatives was proposed for 10 of them. Major compounds were various glycosides of quercetin containing glucose (four compounds), galactose (one compound), xylose (two compounds), arabinose (one compound), or rutinose (one compound) as a carbohydrate residue. Isorhamnetin and 3-O-methylquercetin-3′-O-β-D-glucopyranoside were identified among methyl-containing compounds. The latter compound and reynoutrin, rhamnetin-3-O-β-D-xylopyranosyl-β-D-glucopyranoside, and quercetin-3-O-(6″-O-malonyl)-β-D-glucoside have not been previously found in S. hypericifolia. Data on the presence of quercetin and its derivatives in the extract of S. hypericifolia expand the understanding of the possible practical use of this plant. In addition, the microscopic features of S. hypericifolia leaves were studied. The diagnostic features of the leaf blade necessary for the authentication of raw materials were revealed: straight-walled epidermis cells, stomata located on both sides of the leaf blade (amphistomatic type), two types of trichomes, and wrinkled cuticula with nodi. The main anatomical diagnostic features of the leaves of S. hypericifolia were determined, which makes it possible to assess the authenticity of the raw material.

Enzymatic glycosylations of an α-tocopherol derivative, daidzein, resveratrol, and curcumin were investigated. The plant polyphenol, resveratrol, was incubated with glucosyltransferase from Phytolacca americana. The resveratrol glycoside obtained was then incubated with cyclodextrin glucanotransferase to obtain resveratrol oligosaccharide. Daidzein and curcumin were also converted into daidzein glycoside, daidzein oligosaccharide, and curcumin oligosaccharides. Also, α-tocopherol derivative, that is, 2, 5,7,8-tetram ethyl-2-(4,8-dimethylnonyl)chroman-6-ol, was glycosylated. The glycosides and oligosaccharides had strong anti-allergic activity such as suppression of IgE formation, inhibition of histamine release, and inhibition of O2 - generation. In addition, the glycosides and oligosaccharides showed efficient neuroprotective activity by inhibition of phosphodiesterase. [ABSTRACT FROM AUTHOR]

A new hydrocinnamoyl glucoside, 1-O-(4-hydroxyhydrocinnamoyl)-β-D-glucopyranose (1), together with fifteen known glycosides, including two phenylethanoid glycosides (2--3), two cinnamoyl glycosides (4-5), six phenolic glycosides (6-11), one lignan glycoside (12) and four megastigmane glycosides (13-16) were isolated from a 95% EtOH extract of the Typhonium giganteum rhizomes. The sixteen glycosides were structurally characterized by NMR, HRESIMS, enzymatic hydrolysis and comparison with literature. Upon evaluating inhibitory activities of compounds 1-16 against mushroom tyrosinase at 25 µM, compounds 10 and 11 exhibited obvious inhibitory activities, with %inhibition values of 20.94±0.59%, 23.28±1.09%, respectively, with arbutin used as the positive control (26.21±0.58%). [ABSTRACT FROM AUTHOR]

Bacteria belonging to the phylum Actinobacteria are a very good source of antibiotics, and indeed dominate the current clinical antibiotic space. This paper reports Mutactimycin AP, a new compound belonging to an anthracycline-type family of antibiotics, isolated from a Saccharothrix sp. This actinobacterial strain was isolated from the rhizosphere of lupine plants growing in the extreme hyper-arid Atacama Desert. Structural characterization was carried out using electrospray ionization-mass spectrometry (ESI-MS) and NMR spectroscopy in combination with molecular modelling. The compound was tested against the ESKAPE pathogens, where it showed activity against MRSA and five strains associated with bovine mastitis, where it showed activity against Enterococcus pseudoavium and Staphylycoccus Aureus subsp. Aureus.

Fruit plants produce various volatile compounds that emit distinct aroma characteristics and contribute to their flavor qualities. However, some of these substances, especially hydroxyl-group molecules, are in non-volatile glycosylated forms. This study aimed to determine free and glycosidically bound volatile compounds in three Okinawan pineapple cultivars (‘N67-10′, ‘Yugafu’, and ‘Yonekura’). The free volatile components of squashed pineapple juice were analyzed using solid-phase microextraction (SPME)–arrow-gas chromatography–flame ionization detection/mass spectrometry (GC-FID/MS). The glycosides were collected through solid-phase extraction, hydrolyzed by β-glucosidase, and the released volatile compounds were measured. The sugar moieties of the glycosides were confirmed using GC-MS, and their glycoside constituents were analyzed using liquid chromatography (LC)-MS. Okinawan pineapple varied in its content and composition of free volatile components, which were predominantly comprised of esters, followed by alcohols, terpenes, and ketones. Eight hydroxyl-group compounds, including chavicol, eugenol, geraniol, phenylethyl alcohol, benzyl alcohol, 2-ethyl-1-hexanol, 1-hexanol, and 3-methyl-2-butenol, were released from their glycosylated forms via enzymatic hydrolysis, wherein the amounts of most of them were greater in ‘Yonekura’ than in the other cultivars. Moreover, two glycosides, chavicol-O-β-D-glucopyranoside and eugenol-O-β-D-glucopyranoside, were identified in all the cultivars, wherein the aglycones of both glycosides could be potential odor sources of the medicinal-herbal aromas. These results provide important information regarding both volatile-aroma qualities and bounded-aroma resources in Okinawan pineapple for fresh consumption and agroindustrial processing.