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Purpose Alkylresorcinols (AR) are phenolic lipids present in the bran of wheat and rye. Plasma AR and their urinary metabolites may be suitable biomarkers of whole-grain (WG) wheat and rye consumption. The objective of this study was to examine plasma AR and urinary AR metabolites in response to WG wheat consumption. Methods In a randomized crossover study, 19 subjects (10 males, 9 females; BMI 22.0 kg/m 2 ; age 26 years) incorporated either 3 servings (48 g) or 6 servings (96 g) of WG wheat daily into their regular diet for 1 week. Subjects completed a 2-week washout period, abstaining from all WG consumption, before each intervention. Fasting blood and 24-h urine were collected before and after each intervention. Plasma AR homologues (C19:0, C21:0, C23:0) were quantified by GC–MS after diethyl ether and solid phase extraction and derivatization. Urinary AR metabolites [3,5-dihydroxybenzoic acid and 3-(3,5-dihydroxyphenyl)-propanoic acid] were determined using HPLC with electrochemical detection after enzymatic deconjugation and ethyl acetate extraction. Results Urinary total AR metabolites were significantly higher after 6 compared with 3 servings of WG wheat (56 vs. 32 μmol/day, P  < 0.001). This dose–response relationship was independent of age, sex, energy intake, and baseline urinary AR metabolite concentration. Plasma total AR tended to be higher after 6 compared with 3 servings of WG wheat (103.0 vs. 86.9 nmol/L), but this difference was not significant ( P  = 0.42). Conclusion The results suggest that urinary AR metabolites from 24-h urine collections may be useful as biomarkers of compliance in intervention studies of WG wheat.

Experimental and computed nuclear magnetic resonance data and an iterative synthetic strategy have revealed the correct structures of the baulamycins, potentially important antimicrobial compounds, allowing them to be chemically synthesized. Pinning down the structure of a flexible antibiotic Molecules are often drawn as though they are static chemical structures, but of course in reality they adopt a number of different conformations. The structures of flexible compounds are especially difficult to pin down by conventional means as they can appear as a mixture of conformational isomers. Baulamycins, polyketide antibiotics with long, flexible carbon chains, are one such example and, although they have been the target of synthetic efforts, the true structure of the natural product is unclear. Here, Varinder Aggarwal and colleagues elucidate the structure of the baulamycins by a method based on the correlation of experimental and computed nuclear magnetic resonance data and an iterative synthetic strategy to the target compounds. This approach allowed the unambiguous and correct assignment of the stereocentres and the structure of these natural products and could be applied to other such complex, flexible systems. Small-molecule, biologically active natural products continue to be our most rewarding source of, and inspiration for, new medicines 1 . Sometimes we happen upon such molecules in minute quantities in unique, difficult-to-reach, and often fleeting environments, perhaps never to be discovered again. In these cases, determining the structure of a molecule—including assigning its relative and absolute configurations—is paramount, enabling one to understand its biological activity. Molecules that comprise stereochemically complex acyclic and conformationally flexible carbon chains make such a task extremely challenging 2 . The baulamycins (A and B) serve as a contemporary example. Isolated in small quantities and shown to have promising antimicrobial activity, the structure of the conformationally flexible molecules was determined largely through J -based configurational analysis 3 , 4 , but has been found to be incorrect. Our subsequent campaign to identify the true structures of the baulamycins has revealed a powerful method for the rapid structural elucidation of such molecules. Specifically, the prediction of nuclear magnetic resonance (NMR) parameters through density functional theory—combined with an efficient sequence of boron-based synthetic transformations, which allowed an encoded (labelled) mixture of natural-product diastereomers to be prepared—enabled us rapidly to pinpoint and synthesize the correct structures.

Despite the importance of nanoparticle’s multipods topology in multivalent-interactions enhanced nano-bio interactions, the precise manipulation of multipods surface topological structures is still a great challenge. Herein, the surface-kinetics mediated multi-site nucleation strategy is demonstrated for the fabrication of mesoporous multipods with precisely tunable surface topological structures. Tribulus-like tetra-pods Fe 3 O 4 @SiO 2 @RF&PMOs (RF = resorcinol-formaldehyde resin, PMO = periodic mesoporous organosilica) nanocomposites have successfully been fabricated with a centering core@shell Fe 3 O 4 @SiO 2 @RF nanoparticle, and four surrounding PMO nanocubes as pods. By manipulating the number of nucleation sites through mediating surface kinetics, a series of multipods mesoporous nanocomposites with precisely controllable surface topological structures are formed, including Janus with only one pod, nearly plane distributed dual-pods and tri-pods, three-dimensional tetrahedral structured tetra-pods, etc. The multipods topology endows the mesoporous nanocomposites enhanced bacteria adhesion ability. Particularly, the tribulus-like tetra-pods mesoporous nanoparticles show ~100% bacteria segregation and long-term inhibition over 90% after antibiotic loading. Control of composite nanoparticle topology can be difficult. Here the authors control the topological structure of mesoporous multipods by controlling the number of nucleation sites, and they used the resultant nanoparticles for bacterial adhesion, segregation and antibiotic delivery.

Dichlorobenzene is beneficial to industries, however, the release of this compound into the environment causes significant damage to ecosystems and human health, as it exhibits resistance to biodegradation. Here, we show that chlorophenol and resorcinol are synthesized from 1,3-dichlorobenzene in a water ice environment (1) directly on a poly-crystalline gold surface and (2) after low-energy (<12 eV) electron irradiation of admixture films. For the latter, at energies below 5.5 eV, the electrons solely decompose the chlorinated compound into radicals that further undergo reaction with surrounding water molecules. At higher energies (i.e., >5.5 eV) additional fragments, e.g., hydroxyl radicals, produced from the dissociation of water molecules, may also be involved in the chemistry. The present results may suggest strategies for potential eco-friendly, sustainable, and scalable processes for the mitigation of these halogenated compounds such as cold plasma and radiation, in which low-energy (<10 eV) electrons are predominantly produced.

Two new very-long-chain 5-n-alkylresorcinol (AR) homologues, that is, 5-n-nonacosylbenzene-1,3-diol and 5-n-hentriacontylbenzene-1,3-diol, were isolated from acetone extracts of Ailanthus altissima samaras. These phenolic compounds were detected in nearly equal proportions, although their total content varied considerably between samples from urban-grown trees. No correlation was observed between AR levels and the physiological state of the tree, suggesting that environmental conditions may strongly influence AR biosynthesis in A. altissima. Furthermore, the isolated AR mixture exhibited antifungal activity against soil-borne phytopathogens of the genera Fusarium and Rhizoctonia.

Rye (Secale cereale L.) is one of the most important cereals cultivated in Central and Eastern Europe, valued for its high resistance to environmental stress and high levels of bioactive compounds, such as dietary fiber (DF) and alkylresorcinols (ARR). The aim of the study was to evaluate the content and variability of DF fractions and ARR in rye grain of hybrid and population cultivars. The research was conducted on grain from four rye cultivars cultivated in five locations over three consecutive growing seasons. The content of DF, its fractions, and ARR, was determined using enzymatic–gravimetric and colorimetric methods. The results showed significant variability in all analyzed traits, with environmental conditions and G×E interaction having the greatest impact on their content. Hybrid cultivars were characterized by a higher and more stable content of bioactive compounds. Notable average values for hybrids vs. populations included DF: 153.9 vs. 151.7 g kg−1, NSP: 129.4 vs. 127.7 g kg−1, lignin: 24.5 vs. 24.0 g kg−1, β-glucan: 21.7 vs. 20.6 g kg−1, and ARR: 1015 vs. 987 g kg−1. The KWS Serafino cultivar characterized by the highest and most stable content of bioactive compounds. Selecting genotypes with stable chemical profiles regardless of environmental conditions is crucial for developing nutritionally valuable rye-based products.

In this study, an electrochemical sensor based on a poly(resorcinol) modified carbon nanotube paste electrode (P(RS)/MCNTPE) was successfully developed for the sensitive and selective detection of uric acid (UA) in the presence of dopamine (DA) and riboflavin (RFN). The sensor shows excellent performance in a 0.2 M phosphate buffer solution (PBS) at pH 7.0 with a scan rate 0.1 V/s. Various electrochemical methods were studied including cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Morphological analysis using scanning electron microscopy (SEM) conformed the enhanced surface properties of the bare carbon nanotubes paste electrode (BCNTPE) and the P(RS)/MCNTPE. The effect of pH, scan rate changes 0.025 to 0.25 V/s, revealed that the oxidation of UA follows an adsorption-controlled process. For UA concentration changes from 20 µM and 380 µM, sensor exhibited a limit of detection (LOD) of 0.18 µM and a limit of quantification (LOQ) of 0.61 µM. Optimal UA response was observed at pH 7.0. The sensor shows good stability, repeatability, and reproducibility. Its analytical applicability was successfully validated in real sample analysis.

There are many open questions regarding the hydration of solvent-exposed non-polar tracts and pockets in proteins. Although water is predicted to de-wet purely repulsive surfaces and evacuate crevices, the extent of de-wetting is unclear when ubiquitous van der Waals interactions are in play. The structural simplicity of synthetic supramolecular hosts imbues them with considerable potential to address this issue. To this end, here we detail a combination of densimetry and molecular dynamics simulations of three cavitands, coupled with calorimetric studies of their complexes with short-chain carboxylates. Our results reveal the range of wettability possible within the ostensibly identical cavitand pockets—which differ only in the presence and/or position of the methyl groups that encircle the portal to their non-polar pockets. The results demonstrate the ability of macrocycles to template water cavitation within their binding sites and show how the orientation of methyl groups can trigger the drying of non-polar pockets in liquid water, which suggests new avenues to control guest complexation.Water plays an active role in modulating guest recognition by both artificial and biological hosts, but how this role can be controlled is unclear. Now, the de-wetting of the non-polar pockets of cavitands is shown to be affected by the orientation of methyl groups encircling the portal, which moderate the enthalpic and entropic contributions driving recognition.

Spelt Triticum aestivum L. subsp. spelta (cv. Wirtas), einkorn Triticum monococcum L. (cv. Samopsza) and emmer Triticum dicoccum Schrank (Schuebl) (cv. Płaskurka biała and Płaskurka ciemna) spring wheat cultivars were analyzed and compared to common wheat Triticum aestivum L. subsp. aestivum (cv. Harenda, Kandela, Mandaryna, Serenada, Goplana, Kamelia, Nimfa, Rusałka, Struna, Zadra) cultivated in an organic production system. Moreover, the performance of four common wheat cultivars (cv. Harenda, Kandela, Mandaryna, Serenada) grown in organic, conventional and integrated production systems were compared. The UHPLC-DAD-MS and TLC-DPPH• analyses of specific substances (phenolic acids and alkylresorcinols) were evaluated to ascertain the potential of spring wheat cultivars for promoting human health and suitability for cultivation in an organic production system. The highest yield was observed for the T. aestivum L. subsp. aestivum (modern hull-less) cv. Nimfa (4.45 t/ha), which also demonstrated the lowest resistance to Fusarium spp. infection. Among the contemporary hull-less cultivars, cv. Mandaryna and cv. Harenda exhibited the highest resistance to this pathogen (2.4% and 3.7% of grains infected by Fusarium, respectively), while simultaneously displaying the highest organic phenolic acid content (900.92 and 984.55 µg/g of the grain) and the highest antioxidant potential. It is noteworthy that the cereal hulls of T. monococcum L. (old hulled) (cv. Samopsza) exhibited a markedly elevated content of phenolic acids (approximately 4000 µg/g of the grain). This may have contributed to the reduced incidence of Fusarium infection (9.3% of grains infected) observed in the grains of this cultivar. Furthermore, the hulls proved to be a rich source of phenolics with high antioxidant activity, which is beneficial for human and animal health.

Tyrosinase inhibitors are of great clinical interest as agents for the treatment of hyperpigmentary disorders; however, most compounds described in the literature lack clinical efficiency due to insufficient inhibitory activity against human tyrosinase (hTyr). Recently, we reported that thiazolyl resorcinols (4-resorcinylthiazol-2-amines and -amides) are both selective and efficacious inhibitors of hTyr in vitro and in vivo. Here, we measured dose-activity profiles of a large number of thiazolyl resorcinols and analogous compounds to better understand the molecular basis of their interaction with hTyr. We show that both the resorcinyl moiety and the thiazole ring must be intact to allow efficient inhibition of hTyr, while the substituents at the thiazole 2-amino group confer additional inhibitory activity, depending on their size and polarity. The results of molecular docking simulations were in excellent agreement with the experimental data, affording a rationale for the structural importance of either ring. We further propose that a special type of interaction between the thiazole sulfur and a conserved asparagine residue is partially responsible for the superior inhibitory activity of thiazolyl resorcinols against hTyr.