Comparison on emulsifying and emulgelling properties of low methoxyl pectin with varied degree of methoxylation from different de-esterification methods.

Low methoxyl pectin (LMP) with different degree of methoxylation (DM, 40-50 %, 20-30 % and 5-10 %) were prepared from commercially available citrus pectin using high hydrostatic pressure assisted enzymatic (HHP-pectin) and traditional alkaline (A-pectin) de-esterification method. The results showed that both de-esterification methods and DM exhibited LMPs with varied physicochemical, structural, and functional properties. As the DM decreased, LMP showed a decrease in molecular weight (Mw), while an increase in negative charges and rhamnogalacturonan I (RG-I) ratio, accompanied with better emulsion stability, emulsion gel strength and water-holding properties. Relative to A-pectin, HHP-pectin had higher Mw and lower RG-I side chain ratio, contributing to its better thermal stability, apparent viscosity, and emulgelling properties. HHP-pectin with lower DM (5-10 %) showed superior thickening, emulsifying and emulgelling properties, while that with higher DM (40-45 %) had superior thermal stability, which provided alternative for de-esterification and targeted structural modification of pectin.

Chromatin accessibility mediated transcriptome changes contribute to flavor substance alterations and jasmonic acid hyperaccumulation during oolong tea withering process.

During the oolong tea withering process, abiotic stresses induce significant changes in the content of various flavor substances and jasmonic acid (JA). However, the changes in chromatin accessibility during withering and their potential impact remain poorly understood. By integrating ATAC-seq, RNA-seq, metabolite, and hormone assays, we characterized the withering treatment-induced changes in chromatin accessibility, gene expression levels, important metabolite contents, and JA and JA-ILE contents. Additionally, we analyzed the effects of chromatin accessibility alterations on gene expression changes, content changes of important flavor substances, and JA hyperaccumulation. Our analysis identified a total of 3451 open- and 13 426 close-differentially accessible chromatin regions (DACRs) under withering treatment. Our findings indicate that close-DACRs-mediated down-regulated differentially expressed genes (DEGs) resulted in the reduced accumulation of multiple catechins during withering, whereas open-DACRs-mediated up-regulated DEGs contributed to the increased accumulation of important terpenoids, JA, JA-ILE and short-chain C5/C6 volatiles. We further highlighted important DACRs-mediated DEGs associated with the synthesis of catechins, terpenoids, JA and JA and short-chain C5/C6 volatiles and confirmed the broad effect of close-DACRs on catechin synthesis involving almost all enzymes in the pathway during withering. Importantly, we identified a novel MYB transcription factor (CsMYB83) regulating catechin synthesis and verified the binding of CsMYB83 in the promoter-DACRs regions of key catechin synthesis genes using DAP-seq. Overall, our results not only revealed a landscape of chromatin alters-mediated transcription, flavor substance and hormone changes under oolong tea withering, but also provided target genes for flavor improvement breeding in tea plant.

Discovery of novel indole derivatives that inhibit NEDDylation and MAPK pathways against gastric cancer MGC803 cells.

A series of novel indole derivatives were synthesized and evaluated for their antiproliferative activity against three selected cancer cell lines (MGC803, EC-109 and PC-3). Among these analogues, 2-(5-methoxy-1H-indol-1-yl)-N-(4-methoxybenzyl)-N-(3,4,5-trimethoxyphenyl)acetamide (V7) showed the best inhibitory activity against MGC803 cells with an IC50 value of 1.59 µM. Cellular mechanisms elucidated that V7 inhibited colony formation, induced apoptosis and arrested cell cycle at G2/M phase. Importantly, indole analogue V7 inhibited NEDDylation pathway and MAPK pathway against MGC803 cells.

Two new sesquiterpene lactones from the fruits of Illicium jiadifengpi.

Two new seco-prezizaane-type sesquiterpenes, 3,4-dehydroneomajucin (1) and 1,2,3,4-tetradehydroneomajucin (2), were isolated from the fruits of Illicium jiadifengpi. The structure of these compounds was determined using 1D and 2D NMR and ESI-MS. The isolates were evaluated for their anti-hepatitis B virus activities on the Hep G2.2.15 cell line. The inhibitory rates of compounds 1 and 2 on the HBeAg and HBsAg expression were 30.08 ± 3.09% and 11.43 ± 1.92% at a concentrations of 68.00 µM and 7.88 ± 1.21% and 16.96 ± 4.24% at a concentration of 68.50 µM, respectively.

Sesquiterpenes from the fruits of Illicium jiadifengpi and their anti-hepatitis B virus activities.

Two new compounds, 2S-hydroxyl-jiadifenolide (1) and jiadifenlactone acid (2), and eight known compounds were isolated from the fruits of Illicium jiadifengpi. Their structures were analysed using several spectroscopic techniques, including 1D-, 2D-NMR and HR-ESI-MS experiments. The anti-hepatitis B virus (HBV) activities of the isolates were evaluated via HBV transfection of the Hep G2.2.15 cell line. The inhibitory rates of the most active compounds, compounds 4 and 5, on the HBeAg and HBsAg expression were 28.85±3.15% and 17.53±1.81% and 37.93±2.74% and 23.47±9.52% at concentrations of 64.94µM and 61.35µM, respectively.

A new sesquiterpene lactone from the fruits of Illicium henryi.

AIM: To study the chemical constituents of the fruits of Illicium henryi. METHOD: Chromatographic separations on silica gel, Sephadex LH-20 gel and MCI gel were used to isolate the compounds. The structures were elucidated based on extensive spectroscopic data analyses. RESULTS: Seven compounds were obtained and their structures were identified as 10-benzoyl-cycloparvifloralone (1), cycloparvifloralone (2), 2α-hydroxycycloparviforalone (3), henrylactone B (4), merrillianone (5), henrylactone C (6) and 7, 14-ortholactone- 3-hydroxyfloridanolide (7). CONCLUSION: Compound 1 is a new sesquiterpene lactone. The tested compounds showed weak anti-HBV activities on HBV surface antigen (HBsAg) secretion and HBV e antigen (HBeAg) secretion using Hep G2.2.15 cell line.

Molecular targeted approaches to cancer therapy and prevention using chalcones.

There is an emerging paradigm shift in oncology that seeks to emphasize molecularly targeted approaches for cancer prevention and therapy. Chalcones (1,3-diphenyl-2-propen-1-ones), naturally-occurring compounds with widespread distribution in spices, tea, beer, fruits and vegetables, consist of open-chain flavonoids in which the two aromatic rings are joined by a three-carbon α, ß-unsaturated carbonyl system. Due to their structural diversity, relative ease of chemical manipulation and reaction of α, ß-unsaturated carbonyl moiety with cysteine residues in proteins, some lead chalcones from both natural products and synthesis have been identified in a variety of screening assays for modulating important pathways or molecular targets in cancers. These pathways and targets that are affected by chalcones include MDM2/p53, tubulin, proteasome, NF-kappa B, TRIAL/death receptors and mitochondria mediated apoptotic pathways, cell cycle, STAT3, AP-1, NRF2, AR, ER, PPAR-γ and ß-catenin/Wnt. Compared to current cancer targeted therapeutic drugs, chalcones have the advantages of being inexpensive, easily available and less toxic; the ease of synthesis of chalcones from substituted benzaldehydes and acetophenones also makes them an attractive drug scaffold. Therefore, this review is focused on molecular targets of chalcones and their potential implications in cancer prevention and therapy.

Phytochemical contents and antioxidant capacities of different parts of two sugarcane (Saccharum officinarum L.) cultivars.

Antioxidant capacities and phytochemicals such as phenolics, flavonoids, triterpenoids, phytosterols of four parts of two sugarcane cultivars have been characterised. The total triterpenoid content (TTC), total phenolic content (TPC), total flavonoid content (TFC) and total sterol content (TSC) were different among parts and cultivars of sugarcane. The node of both cultivars contained the highest TTC (2096.02 and 1779.66 mg ursolic acid/100g DW for green-rind and red-rind sugarcane, respectively). However, the highest TPC, TFC and TSC were found in the rind. Green-rind sugarcane cultivars contained higher TSC than the red-rind sugarcane cultivars in most parts, while opposite trend were found in TPC and TFC. Stigmasterol and ß-sitosterol were found as two main phytosterols. Furthermore, TPC and TFC revealed good correlations with DPPH and FRAP. As cultivars and parts could affect phytochemical content, present result may provide a theoretical basis for further exploitation of the health beneficial resources of sugarcane.

Two new monoterpenes from the fruits of Illicium lanceolatum.

Two new monoterpenes, p-mentha-1(7),8-dien-2-O-ß-D-glucoside and trans-2,4-dihydroxy-2,4-dimethyl-trans-1-acetic acid γ-lactone were isolated from the fruits of Illicium lanceolatum along with trans-2,4-dihydroxy-2,4-dimethyl-cis-1-acetic acid γ-lactone, (1R,2R,4R)-8-p-menthen-1,2-diol, trans-sobrerol, (1S,2S,4R)-p-menthane-1,2,8-triol and (1S, 2S, 4R, 8R)-p-menthane-1,2,9-triol. The structures of the isolates were confirmed by spectroscopic analysis and they showed no inhibitory effects on the in vitro growth of microbial organisms (Escherichia coli, Staphyloccocus aureus, Bacillus subtilis) at less than 1.0 mg/mL.

Diterpenoid alkaloids from Aconitum kirinense.

A new C(18)-diterpenoid alkaloid, kirinenine A (1), was isolated from the root of Aconitum kirinense, along with eight known diterpenoid alkaloids. The structures of all compounds were characterized on the basis of extensive NMR and MS analyses and by comparison with literature values, and the new one was further confirmed by X-ray crystallographic diffraction. All the compounds were isolated from the title plant for the first time.

AsnB, regulated by diffusible signal factor and global regulator Clp, is involved in aspartate metabolism, resistance to oxidative stress and virulence in Xanthomonas oryzae pv. oryzicola.

Xanthomonas oryzae pv. oryzicola (Xoc) causes bacterial leaf streak in rice, which is a destructive disease worldwide. Xoc virulence factors are regulated by diffusible signal factor (DSF) and the global regulator Clp. In this study, we have demonstrated that asnB (XOC_3054), encoding an asparagine synthetase, is a novel virulence-related gene regulated by both DSF and Clp in Xoc. A sequence analysis revealed that AsnB is highly conserved in Xanthomonas. An asnB mutation in Xoc dramatically impaired pathogen virulence and growth rate in host rice, but did not affect the ability to trigger the hypersensitive response in nonhost (plant) tobacco. Compared with the wild-type strain, the asnB deletion mutant was unable to grow in basic MMX (-) medium (a minimal medium without ammonium sulphate as the nitrogen source) with or without 10 tested nitrogen sources, except asparagine. The disruption of asnB impaired pathogen resistance to oxidative stress and reduced the transcriptional expression of oxyR, katA and katG, which encode three important proteins responsible for hydrogen peroxide (H(2)O(2)) sensing and detoxification in Xanthomonas in the presence of H(2)O(2), and nine important known Xoc virulence-related genes in plant cell-mimicking medium. Furthermore, the asnB mutation did not affect extracellular protease activity, extracellular polysaccharide production, motility or chemotaxis. Taken together, our results demonstrate the role of asnB in Xanthomonas for the first time.

[Studies on the constituents from Cacalia ambigua].

OBJECTIVE: To study the constituents of Cacalia ambigua. METHODS: The chemical constituents were isolated from the plant by all kinds of column chromatographies and their structures were identified by spectral methods. RESULTS: Four compounds were isolated and identified as ent-kaur-16-en-19-oic acid (1), 13-beta-Kaur-16 beta-ol (2), beta-sitosterol (3) and 1-glyceryl nonadecanoic acid ester (4). CONCLUSION: Compounds 1-4 are isolated from this plant for the first time, and compounds 1 and 2 and isolated from this genus for the first time.