Preparation, antioxidant and tyrosinase inhibitory activities of chitosan oligosaccharide-hydroxypyridinone conjugates.

Two novel chitosan oligosaccharide (COS)-hydroxypyridone (HPO) conjugates were prepared by reacting chitosan oligosaccharide with 2-chloromethyl-5-hydroxypyridone (HPO), which was synthesized by a series of reactions starting from kojic acid. The degree of substitution of COS-HPO2 reached 1.2, with a yield of 74.

A novel chitosan oligosaccharide derivative: Synthesis, antioxidant and antibacterial properties.

A novel thioether chitosan oligosaccharide (COS-All-Tio) was prepared by the reaction of chitosan oligosaccharide (COS) with 3-bromopropene, followed by the coupling with tiopronin (Tio) using a thiol-ene reaction. The degree of substitution of COS-All-Tio reached 1.48.

Structurally Diverse Polycyclic Salicylaldehyde Derivative Enantiomers from a Marine-Derived Fungus sp. SCSIO F452.

To enlarge the chemical diversity of sp. SCSIO F452, a talented marine-derived fungus, we further investigated its chemical constituents from a large-scale fermentation with modified culture. Four pairs of new salicylaldehyde derivative enantiomers, euroticins F-I (-), as well as a known one eurotirumin () were isolated and characterized.

Micropyrones A and B, two new -pyrones from the actinomycete sp. GJ312 isolated from Fisch.

Two new -pyrones, micropyrones A () and B (), along with four known -pyrones, nocapyrone D (), nocapyrone A (), marinactinone A (), and nocapyrone H (), were isolated from the culture extract of actinomycete sp. GJ312, which was isolated from . The structures of these compounds were identified by analysis of spectral data.

Asperorydines N-P, three new cyclopiazonic acid alkaloids from the marine-derived fungus Aspergillus flavus SCSIO F025.

Three new tricyclic cyclopiazonic acid (CPA) related alkaloids asperorydines N-P (1-3), together with six known compounds (4-9) were isolated and characterized from the fungus Aspergillus flavus SCSIO F025 derived from the deep-sea sediments of South China Sea. The structures including absolute configurations of 1-3 were deduced from spectroscopic data, X-ray diffraction analysis, and electronic circular dichroism (ECD). All compounds were evaluated for the antioxidative activities against DPPH, cytotoxic activities against four tumor cell lines (SF-268, HepG-2, MCF-7, and A549), and antimicrobial activities.

Purification and Biological Activities of Enzymatically Degraded Sargassum fusiforme Polysaccharides.

Enzymatic hydrolysate of the crude polysaccharide (SFP) extracted from Sargassum fusiforme was purified by column DEAE-52 and Sephadex G-100 to yield four components, namely, ESFP1, ESFP2, ESFP3 and ESFP4. These components were characterized by chemical composition assay, GC/MS, HPGPC, UV and FT-IR techniques. The in vitro antioxidant activities of the four purified fractions were investigated by measuring their radical scavenging activity and reducing power.

Synthesis and Cytotoxic Property of Annonaceous Acetogenin Glycoconjugates.

Background: Annonaceous acetogenins (ACGs) are secondary metabolites produced by the Annonaceae family and display potent anticancer activity against various cancer cell lines. Squamocin and bullatacin are two examples of ACGs that show promising antitumor activity; however, preclinical data are not sufficient partly due to their being highly lipophilic and poorly soluble in water. These compounds also display high toxicity to normal cells.

Bioactive Diarylheptanoids from Alpinia coriandriodora.

Eight new diarylheptanoids, coriandralpinins A-H (1-8), were isolated from the rhizomes of Alpinia coriandriodora, an edible plant of the ginger family. Their structures, including the absolute configurations, were established by extensive spectroscopic analysis and ECD calculations. Compounds 1-8 have a 1,5-O-bridged diarylheptanoid structure featuring polyoxygenated aryl units.

Dihydrochalcones from the leaves of .

Three new phlorizin derivatives, 6"--vanilloylphlorizin (), 6"--(4-hydroxybenzoyl)phlorizin (), 6"--feruloylphlorizin (), along with four known dihydrochalcones, phlorizin (), 3-hydroxyphlorizin, trilobatin, and 6"--acetylphlorizin were isolated from the leaves of . Their structures were established by analysis of extensive spectroscopic data. The new compounds were shown to be non-cytotoxic when tested against A549, HeLa, HepG2, and MCF-7 cell lines.

Effect of enzymatic degraded polysaccharides from Enteromorpha prolifera on the physical and oxidative stability of fish oil-in-water emulsions.

To explore the potential application of enzymatic degraded polysaccharides from Enteromorpha prolifra (EEP) as antioxidant in fish oils, a stable fish oil emulsion system incorporating EEP was established. Effects of emulsifier (Tween 80, gum arabic and lecithin) and EEP concentration on the physical characteristics of fish oil emulsions were investigated. The results indicated that Tween 80 was the best choice, and 1% (w/w) of EEP was the optimum concentration for the preparation of fish oil emulsions.

Co-immobilization of pectinase and glucoamylase onto sodium aliginate/graphene oxide composite beads and its application in the preparation of pumpkin-hawthorn juice.

Co-immobilization of pectinase and glucoamylase onto sodium alginate/graphene oxide beads was achieved by N,N'-dicyclohexylcarbodiimide/N-hydroxysuccinimide as activating agent. The co-immobilized pectinase-glucoamylase (I-PG) prepared under optimal conditions (pH 4.0, 40°C and 35 min) possessed pectinase activity of 1,227.

Application of the LMS method of constructing fetal reference charts: comparison with the original method.

In view of the concern expressed about the current references, new references for fetal biparietal diameter and head circumference should be constructed for contemporary local populations. We conducted a retrospective cross-sectional study in two hospitals in Guangdong, Southern China. Fetal biparietal diameter and head circumference percentiles regression were fitted using Cole's LMS method.

Antioxidant and antimicrobial evaluation of carboxymethylated and hydroxamated degraded polysaccharides from Sargassum fusiforme.

In order to improve the bioactivity of the polysaccharide from Sargassum fusiforme (PSF), the degraded polysaccharide (DPSF) was modified by carboxymethylation, yielding carboxymethylated degraded polysaccharides (CDPSF), which were further modified to generate hydroxamated derivatives (HCDPSF). Both CDPSF and HCDPSF were characterized by Fourier transform infrared spectroscopy. The molecular weight of CDPSF and HCDPSF was found to be 354 kDa and 375 kDa, respectively.

Eurotiumins A⁻E, Five New Alkaloids from the Marine-Derived Fungus sp. SCSIO F452.

Three new prenylated indole 2,5-diketopiperazine alkaloids (⁻) with nine known ones (⁻), one new indole alkaloid (), and one new bis-benzyl pyrimidine derivative () were isolated and characterized from the marine-derived fungus sp. SCSIO F452. and , occurring as a pair of diastereomers, both presented a hexahydropyrrolo[2,3-]indole skeleton.

Characterization and immunological activity of polysaccharides from Ixeris polycephala.

A water-soluble polysaccharide, named KMCP, was isolated and purified from edible plant Ixeris polycephala by using DEAE-52 cellulose chromatography. Its structure was determined by chemical analysis, methylation analysis, and NMR analysis, coupled with characterization by scanning electron spectroscopy (SEM). The resulting data indicated that KMCP was an arabinogalactan, with an average molecular weight of 1.

Xylarodons A and B, new hexaketides from the endophytic fungus Xylaria sp. SC1440.

Two new hexaketides, xylarodons B (1) and C (2), were isolated from solid cultures of the endophytic fungus Xylaria sp. SC1440. The structures of these compounds were elucidated on the basis of detailed 1D, 2D NMR, and HRESIMS analysis.

Pteridic acids C-G spirocyclic polyketides from the marine-derived Streptomyces sp. SCSGAA 0027.

Five new pteridic acids C-G (1-5) were isolated from a culture broth of the marine-derived actinomycete Streptomyces sp. SCSGAA 0027. Their complete structures were elucidated on the basis of NMR data, modified Mosher's method and quantum chemical calculations.

Advanced technology for nanostarches preparation by high speed jet and its mechanism analysis.

Nanostarches were successfully prepared by high speed jet (HSJ) after pretreatment of micronization. The nanostarches were obtained at the conditions of micronization treatment for 60min, and then one cycle at 240MPa of HSJ (188.1nm).

Spiro Meroterpenoids from Ganoderma applanatum.

Spiroapplanatumines A-Q (1-12, 14-16, 18, and 20), new spiro meroterpenoids respectively bearing a 6/5/7 or 6/5/5 ring system, along with three known compounds, spirolingzhines A, B, and D, were isolated from the fruiting bodies of the fungus Ganoderma applanatum. Their structures including absolute configurations were assigned by using spectroscopic methods, ECD and C NMR calculations, and single-crystal X-ray diffraction analysis. Biological evaluation of all the compounds disclosed that compounds 7 and 8 inhibited JAK3 kinase with IC values of 7.

Protein-peptide nutritional material prepared from surimi wash-water using immobilized chymotrypsin-trypsin.

Background: In the production process of surimi, large quantities of wastewater are produced. Thus it would be interesting to develop an efficient protocol for the recovery of protein from hairtail surimi wash-water.

Results: A technique involving the use of immobilized chymotrypsin-trypsin (I-CT) was developed, providing a practical method for the preparation of protein-peptide nutritional material (PPNM).

Solvent-Induced Single Crystal-Single Crystal Transformation of an Interpenetrated Three-Dimensional Copper Triazole Catalytic Framework.

The 2-fold interpenetrated 3D framework 1 can be solvent-induced to noninterpenetrated framework 1' in a reversible single crystal-single crystal transformation fashion. In addition, 1' represents the first catalyst based on triazole to catalyze the aerobic homocoupling of various substituted arylboronic acids.

Flavonoids from Pronephrium megacuspe.

A chemical investigation of the whole plant of Pronephrium megacuspe (Bak.) Holtt. led to the isolation of four flavonoids, pronephrones A-D (1-4), which were firstly reported.

Synthesis and cancer cell growth inhibitory activity of icaritin derivatives.

A series of icaritin derivatives bearing carboxylic acid or carboxylic ester groups are synthesized, and their in vitro cytotoxic activity against three cancer cell lines, MCF-7, MDA-MB-435s, and A549, are evaluated by MTT assay. Several derivatives including 2h, 2j, 5b and 5d show higher cytotoxic activity than the parent compound icaritin against these cancer cell lines. Compounds 5b and 5d are even more cytotoxic to MCF-7 cells than the clinic drug tamoxifen.