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Haaning Otte posted an update 6 months, 1 week ago
No symptoms were observed in the resistant genotype. Starch granules, vessel occlusions, and lipid droplets were the main distinguishable characteristics between susceptible and tolerant varieties.Alocasia macrorrhiza (L.) Schott, known as Alocasia is found in the Araceae, and is widely planted in southern China for its ornamental and medicinal value. This plant has a wide range of pharmacological effects, and has potential anti-tumor activity (Lei et al. 2013). In July of 2019, leaf spots were observed on A. macrorrhiza in the Xixiangtang Area, Nanning, Guangxi, China. Disease symptoms began with water-soaked yellow-green spots and progressed to form brown, round or oval lesions with yellow halos. Under severe conditions, spots merged into larger irregular lesions. More than 60% of the plants in a 0.5 ha field showed disease symptoms. Symptomatic leaves were collected and cut into small pieces (3×3 mm). Leaf pieces from the margin of the necrotic tissue were surface sterilized in 75% alcohol for 10 s, followed by 2% sodium hypochlorite solution for 2 min, then rinsed three times in sterile distilled water. Tissues were plated on potato dextrose agar (PDA) and incubated at 28°C for 5 days in the dark. hina. The identification of this pathogen provides a foundation for the management of leaf spot on this medicinal plant.This work describes the high capacity of MelA α-galactosidase from Lactobacillus plantarum WCFS1 to transfer galactosyl residues from melibiose to the C6-hydroxyl group of disaccharide-acceptors with β-linkages (lactulose, lactose, and cellobiose) or α-linkages (isomaltulose and isomaltose) to produce novel galactose-containing hetero-oligosaccharides (HOS). A comprehensive nuclear magnetic resonance characterization of the transfer products derived from melibioselactulose reaction mixtures revealed the biosynthesis of α-d-galactopyranosyl-(1 → 6)-β-d-galactopyranosyl-(1 → 4)-β-d-fructose as the main component as well as the presence of α-d-galactopyranosyl-(1 → 3)-β-d-galactopyranosyl-(1 → 4)-β-d-fructose and α-d-galactopyranosyl-(1 → 6)-α-d-galactopyranosyl-(1 → 6)-β-d-galactopyranosyl-(1 → 4)-β-d-fructose. Melibiose-derived α-galactooligosaccharides (α-GOS), manninotriose and verbascotetraose, were also simultaneously synthesized. An in vitro assessment of the intestinal digestibility of the novel biosynthesized HOS revealed a high resistance of α-galactosides derived from lactulose, lactose, cellobiose, and isomaltulose. According to the evidence gathered for conventional α-GOS and certain disaccharides used as acceptors in this work, these novel nondigestible α-galactosides could be potential candidates to selectively modulate the gut microbiota composition, among other applications, such as low-calorie food ingredients.The main reasons for the discontinuation of contact lens wear are ocular dryness and discomfort. Proteoglycan 4 (PRG4), a mucinous glycoprotein, and hyaluronic acid (HA), a nonsulfated linear glycosaminoglycan, are naturally present in the eye and contribute to ocular hydration and lubrication. This study aimed to investigate the impact of the structure of the recombinant human PRG4 (rhPRG4)/HA complex on contact lens properties, when one agent is grafted and the counterpart is physisorbed on the surface of model conventional or silicone contact lens materials. Investigation of the wettability, water retention, antifouling, and boundary lubricant properties of the prepared hydrogels showed that the rhPRG4/HA interactions varied with the rhPRG/HA configuration on the hydrogel surface as well as the composition of the underlying substrate used. The rhPRG4-physisorbed/HA-grafted sample was characterized by better antifouling and boundary lubricant properties on the model conventional hydrogels, while the HA-physisorbed/rhPRG4-grafted sample exhibited improved surface wettability, antifouling, and water-retentive properties on the model silicone hydrogels. ND646 nmr The results of this study contribute to the design of biomimetic contact lens surfaces that work synergistically with ocular fluid-phase biological agents to enhance compatibility between the contact lens and the ocular environment, alleviating dry eye symptoms and improving comfort.Gold-catalyzed cascade cyclization and 1,3-difunctionalization of 2-(1-alkyny)-2-alken-1-ones with N,O-acetals are described, leading to the discovery of novel 1,3-oxyaminomethylation and 1,3-aminomethylamination. Typically, by varying the reaction conditions especially the gold catalysts, these two distinct reaction pathways can be controlled in a selective manner. Moreover, tandem cyclization and 1,4-oxyaminomethylation have also been achieved.Dissociation of water molecules after soft X-ray absorption can yield neutral fragments in high-Rydberg (HR) states. We have studied the production of such fragments by field ionization and ion time-of-flight (TOF) spectrometry. Neutral HR fragments are created at all resonances below the O 1s ionization potential (IP) and particularly within 1 eV above the O 1s IP. The latter effect is due to the recapture of the O 1s photoelectrons into HR orbitals of the molecular water ion after the emission of a fast Auger electron. H2O+(HR) fragments subsequently dissociate, yielding neutral H(HR) and O(HR) fragments, as were found by measuring the TOF spectra by pulsed field ionization. Such measurements were carried out at the O 1s → 4a1 and 2b2 resonances as well as just above the O 1s IP. The TOF spectra also reveal two series of oscillatory structures that are attributed to quantum beats involving Lyman emission in one of the series and field ionization of H(HR) fragments in the other series.The author describes his 60-year career in studying the chemistry of natural products, which includes structural, synthetic, and biosynthetic studies of natural products ranging from insect pigments, antibiotics, and fecal mutagens to taxol and other anticancer natural products as well as antimalarial natural products. One of the compounds discussed, napabucasin, is now an anticancer drug in phase III clinical trials.