Integration of soil microbiology and metabolomics to elucidate the mechanism of the accelerated infestation of tobacco by the root-knot nematode.

Introduction: Tobacco root-knot nematode (TRKN) disease is a soil-borne disease that presents a major hazard to the cultivation of tobacco, causing significant reduction in crop quality and yield, and affecting soil microbial diversity and metabolites. However, differences in rhizosphere soil microbial communities and metabolites between healthy tobacco soils and tobacco soils with varying degrees of TRKN infection remain unclear. Methods: In this study, diseased rhizosphere soils of tobacco infected with different degrees of TRKN [severally diseased (DH) soils, moderately diseased (DM) soils, and mildly diseased (DL) soils] and healthy (H) rhizosphere soils were collected. Here, we combined microbiology with metabolomics to investigate changes in rhizosphere microbial communities and metabolism in healthy and TRKN-infected tobacco using high-throughput sequencing and LC-MS/MS platforms. Results: The results showed that the Chao1 and Shannon indices of bacterial communities in moderately and mildly diseased soils were significantly higher than healthy soils. The Proteobacteria, Actinobacteria, Ascomycota, Burkholderia, Bradyrhizobium and Dyella were enriched in the rhizosphere soil of healthy tobacco. Basidiomycota, Agaricales, Pseudeurotiaceae and Ralstonia were enriched in severally diseased soils. Besides, healthy soils exhibited a relatively complex and interconnected network of bacterial molecular ecologies, while in severally and moderately diseased soils the fungal molecular networks are relatively complex. Redundancy analysis showed that total nitrogen, nitrate nitrogen, available phosphorus, significantly affected the changes in microbial communities. In addition, metabolomics results indicated that rhizosphere soil metabolites were significantly altered after tobacco plants were infected with TRKNs. The relative abundance of organic acids was higher in severally diseased soils. Spearman's analyses showed that oleic acid, C16 sphinganine, 16-hydroxyhexadecanoic acid, D-erythro-3-methylmalate were positively correlated with Basidiomycota, Agaricales, Ralstonia. Discussion: In conclusion, this study revealed the relationship between different levels of TRKN invasion of tobacco root systems with bacteria, fungi, metabolites and soil environmental factors, and provides a theoretical basis for the biological control of TRKN disease.

Effect of nano-Al2O3 and multi-walled carbon nanotubes on the anaerobic mono-digestion of sludge and the co-digestion of tobacco waste and sludge.

Anaerobic digestion can help mitigate tobacco waste (TW) pollution. Both the mono-digestion of sludge and the co-digestion of TW and sludge were considered in this study. Additionally, the effects of nano-Al2O3 and multi-walled carbon nanotubes (MWCNTs) on these two digestion systems were investigated through a 35 day digestion experiment. The microbial communities in the control reactors and the nano-Al2O3 reactors were also examined. Kinetic analysis revealed that the Rm values for the mono- and co-digestion nano-Al2O3 reactors increased by 8.88% and 13.5% compared with that of the MWCNTs reactor, respectively. Furthermore, the co-digestion system exhibited a 34.8% higher Rm than the mono-digestion system when nano-Al2O3 was added to both systems. Nano-Al2O3 was found to shorten the lag phase, while MWCNTs prolonged the lag phase time. Furthermore, 16S RNA amplicon sequencing results indicated that microbial species such as Methanobacterium sp., Hydrogenispora sp., Lutispora sp., and Ruminiclostridium sp. were more abundant in the nano-Al2O3 reactor. These results demonstrated that biogas production in co-digestion systems was improved. Moreover, nano-Al2O3 addition enhanced biogas production.

Chemical composition and antioxidant activity of petroleum ether fraction of Rosmarinus officinalis.

The presented study examines the chemical composition and antioxidant activity of the petroleum ether fraction of Rosmarinus officinalis (PEF-RO), which was obtained via 75 % ethanol extraction followed by petroleum ether extraction. The obtained fractions were analyzed by gas chromatography-mass spectrometry (GC-MS). The in vitro antioxidant activity of PEF-RO was investigated using various assays, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulfonate (ABTS) free radical scavenging, and ferric reducing antioxidant power (FRAP) method. A total of 82 chemical components were successfully identified, totaling 10.06 % of PEF-RO content. The identified components consisted of 24 hydrocarbons, 14 ketones, 16 alcohols, 4 phenols, 14 esters, and 10 other compounds. Notably, verbenone (2.4377 %), vitamin A (0.6854 %), trans-geraniol (0.5998 %), linolenic acid (0.5713 %), and 1,8-eucalyptol (0.5323 %) were the most abundant compounds, and there are many trace components in PEF-RO. PEF-RO's IC50 values of DPPH and ABTS free radical scavenging were determined as 0.36 mg/mL and 0.19 mg/mL, respectively. FRAP-method was employed to measure the total antioxidant energy of PEF-RO, which displayed good antioxidant activity. The obtained data provides the foundation for the comprehensive development and utilization of Rosmarinus officinalis.

DMSO-promoted direct δ-selective arylation of p-quinone methenylpiperidine bearinides to generate fuchsones under metal-free conditions by employing p-QMs themselves or substituted phenols as aryl sources.

Fuchsones have wide applications in modern society. Present methods for generating fuchsones have many disadvantages and there are significant limitations for further exploration of fuchsone applications. Herein, we describe a DMSO-promoted direct δ-selective arylation of p-QMs to synthesize symmetrical and unsymmetrical fuchsones under metal-free conditions by employing p-QMs themselves or substituted phenols as aryl sources. As unprecedented methods, these novel strategies present a great advantage and significance for further exploration of fuchsones and the development of new applications.

Silicon fertilization enhances the resistance of tobacco plants to combined Cd and Pb contamination: Physiological and microbial mechanisms.

Remediation of soil contaminated with cadmium (Cd) and lead (Pb) is critical for tobacco production. Silicon (Si) fertilizer can relieve heavy metal stress and promote plant growth, however, it remains unknown whether fertilization with Si can mitigate the effects of Cd and Pb on tobacco growth and alter microbial community composition in polluted soils. Here we assessed the effect of two organic (OSiFA, OSiFB) and one mineral Si fertilizer (MSiF) on Cd and Pb accumulation in tobacco plants, together with responses in plant biomass, physiological parameters and soil bacterial communities in pot experiments. Results showed that Si fertilizer relieved Cd and Pb stress on tobacco, thereby promoting plant growth: Si fertilizer reduced available Cd and Pb in the soil by 37.3 % and 28.6 %, respectively, and decreased Cd and Pb contents in the plant tissue by 42.0-55.5 % and 17.2-25.6 %, resulting in increased plant biomass by 13.0-30.5 %. Fertilization with Si alleviated oxidative damage by decreasing malondialdehyde content and increasing peroxidase and ascorbate peroxidase content. In addition, Si fertilization increased photosynthesis, chlorophyll and carotenoid content. Microbial community structure was also affected by Si fertilization. Proteobacteria and Actinobacteria were the dominant phylum in the Cd and Pb contaminated soils, but Si fertilization reduced the abundance of Actinobacteria. Si fertilization also altered microbial metabolic pathways associated with heavy metal resistance. Together, our results suggest that both organic and mineral Si fertilizers can promote tobacco growth by relieving plant physiological stress and favoring a heavy metal tolerant soil microbial community.

Diterpenes from oriental tobacco Nicotiana tabacum 'YNOTBS1' and their bioactivities.

Seven diterpenes including two new seco-cembranoid basmanoids A (1) and B (2), and two new labdane basmadanes A (3) and B (4), and three known compounds (-)-dehydro-nor-ambreinolid (5), (13E)-8-hydroxy-13-labden-12-one (6), and 14,15,16-dinor-7-oxolabda-8-ene-13-oic acid (7) were isolated from oriental tobacco Nicotiana tabacum 'YNOTBS1'. Compounds 1-3 and 5 showed anti-tobacco mosaic virus (TMV) activity with inhibition rates in the range of 30-69% at the concentration of 1 mg/mL. However, none of them exhibited any inhibitory effects against nitric oxide (NO) production in LPS and IFN-γ-induced RAW 264.7 murine macrophages and anti-proliferative activities against cancer cell lines SMMC-7721 and A-549.

Four new C19-diterpenoid alkaloids from Aconitum hemsleyanum var. circinatum.

Four new C19-diterpenoid alkaloids, hemaconitines A-D (1-4), were isolated from the roots of Aconitum hemsleyanum var. circinatum. Their structures were elucidated as 19R-hydroxyl-secoyunnaconitine (1), (3R)-hydroxyl-liwaconitine (2), 14-anisoyl-leucanthumsine E (3), and 19R -acetonyl-8-O-methyltalatisamine (4) by extensive spectroscopic analysis (IR, UV, HR-ESI-MS, 1D, and 2D NMR).

New Labdane diterpenes from Hedychium yunnanense with cytotoxicity and inhibitory effects on nitric oxide production.

Two new labdane diterpenes, hedychenoids A (1) and B (2), were isolated from the rhizomes of Hedychium yunnanense, together with four known ones hedychenone (3), forrestin A (4), villosin (5) and calcaratarin C (6). Their structures were determined on the basis of NMR (1D and 2D) and mass spectroscopic analysis. Compounds 2, 3 and 5 exhibited cytotoxicity against SGC-7901 with IC50 values of 14.88 ± 0.52, 7.08 ± 0.21 and 7.76 ± 0.21 µg/ml, 3 and 5 against HeLa with IC50 values of 9.76 ± 0.48 and 13.24 ± 0.63 µg/ml, respectively. Compounds 2, 5 showed inhibitory effects against nitric oxide production in LPS and IFN-γ-induced RAW 264.7 murine macrophages with IC50 values of 6.57 ± 0.88 and 5.99 ± 1.20 µg/ml, respectively.

Cytotoxic labdane-type diterpenes from Hedychium longipetalum inhibiting production of nitric oxide.

Three new labdane diterpenes, hedylongnoids A (1), B (2) and C (3), were isolated from the rhizomes of Hedychium longipetalum, together with three known ones yunnancoronarin A (4), hedyforrestin C (5) and hedyforrestin B (6). Their structures were established by spectroscopic analysis, including 2D-NMR spectroscopic techniques. Compounds 1-6 exhibited inhibitory effects against nitric oxide (NO) production in LPS and IFN-γ-induced RAW 264.7 murine macrophages with IC50 values ranging from 0.56 to 7.50 µg/ml, and 3-6 showed cytotoxicities against cancer cell lines SGC-7901 and Hela with IC50 values ranging from 6.21 to 14.53 µg/ml and from 6.58 to 14.83 µg/ml, respectively.

8-9' linked neolignans with cytotoxicity from Alpinia conchigera.

Five new 8-9' linked neolignans conchigeranals A-E (1-5), together with three known compounds galanganal (6), galanganols A (7) and B (8), were isolated from the whole plant of Alpinia conchigera. Their structures were established by spectroscopic analysis, including 2D-NMR spectroscopic techniques. Cytotoxicities of compounds 1-8 were tested against two cancer cell lines A549 and Hela. Results showed that 4, 5, 7 and 8 exhibited cytotoxicity against A549 with the IC50 values of 12.36, 9.72, 10.26, 13.05 µg/ml, respectively, and 1-8 against Hela with the IC50 values from 1.53 to 5.29 µg/ml.

Three unusual sesquineolignans from Alpinia conchigera.

Three unusual sesquineolignans conchignans A, B, and C, together with two known compounds vanillin and phloroglucinol, were isolated from the whole plants of Alpinia conchigera. Their structures were established by spectroscopic analysis, including 2D NMR spectroscopic techniques.

Apoptosis induction and G2/M arrest of 2-methyl-1,3,6-trihydroxy-9,10-anthraquinone from Rubia yunnanensis in human cervical cancer Hela cells.

2-Methyl-1,3,6-trihydroxy-9,10-anthraquinone (MTA), one of the major components isolated from the traditional Chinese medicine Rubia yunnanensis, exhibited inhibitory activity on the proliferation of several human cancer cell lines. The results from an annexin V-FITC (fluoresein-5-isothiocyanate) apoptosis assay and DNA content analysis showed that MTA exerted cytotoxicity via apoptosis induction and G2/M cell cycle arrest in human cervical carcinoma HeLa cells. Further, MTA was found to induce apoptosis of HeLa cells through the mitochondria-mediated pathway. It caused the translocation of Bax to the mitochondria and release of cytochrome c into the cytosol, which caused the cleavage of caspase and poly(ADP-ribose) polymerase and finally triggered the apoptosis. Furthermore, the p53/p21/Cdc2-cyclin B1 signaling was found related to the G2/M arrest caused by MTA. The over-expression of p21 and down-expression of cyclin B1 caused by MTA inactivated the Cdc2-cyclin B1 complex of G2/M checkpoint and finally caused the G2/M arrest in HeLa cells. This study demonstrated that MTA is a potential anti-cancer component of R. yunnanensis, a folk anti-cancer herb used in Yunnan, China.

[Chemical constituents contained in ethanol extracts from Acorus tatarinowii and their anti-fatigue activity].

Chemical constituents in ethyl acetate and butanol fractions of ethanol extracts from Acorus tatarinowii were separated by column chromatography. Bufo skeletal muscle fatigue model was established to study the anti-fatigue activity of separated compounds. Five compounds were separated and identified by spectroscopic analysis as acoramone(1),cycloartenone(2),2,4,5-trimethoxyl-2'-butoxy-1,2-phenyl propandiol(3),5-hydroxymethyl furfural(4), and 5-butoxymethyl furfural(5). Compound 3 was a new compound, and compounds 2 and 5 were separated from this plant for the first time. Compound 4 exhibited a notable anti-fatigue activity.

Cytotoxic sesquiterpenes and lignans from Saussurea deltoidea.

Two new sesquiterpenes deltoiden A (1) and deltoiden B (2), and two new lignans deltoignan A (9) and deltoignan B (10), together with 14 known compounds, including six sesquiterpenes 3-8 and three lignans 11-13, were isolated from the whole plant of Saussurea deltoidea. Compounds 3-8 and 11-17 were isolated for the first time from this plant. Their structures were established by spectroscopic analysis, including 2D-NMR spectroscopic techniques. Cytotoxicities of compounds 1-13 were tested against three cancer cell lines A549, Hela and SMMC-7721. Results showed that 5, 6 and 7 exhibited cytotoxicity against SMMC-7721 with the IC(50) values of 6.49, 9.53, 1.23 µg/ml, 5 and 7 against A549 with the IC(50) values of 4.99 and 5.35 µg/ml, 5, 6, 7, 13 against Hela with the IC(50) values of 1.40, 4.75, 0.93 and 5.42 µg/ml, respectively. The structure-activity relationships of sesquiterpenes 1-8 were discussed on the base of cytotoxic results.

Inhibitory activity of eudesmane sesquiterpenes from Alpinia oxyphylla on production of nitric oxide.

Sixteen eudesmane-type sesquiterpenes including seven new compounds oxyphyllanene A-G (1-2 and 5-9) were isolated from the fruits of Alpinia oxyphylla. Among them, compounds 1-2 are novel trinoreudesmane sesquiterpenes, and 5 is a noreudesmane one. Their structures were established by spectroscopic analysis, including 2D-NMR techniques. Inhibitory activity of compounds 3-8 and 10-16 were tested against nitric oxide production in LPS and IFN-γ-induced RAW 264.7 murine macrophages, and their IC(50) values ranged from 9.85 to 13.95 µg/ml.

[Phenolic compounds from Jatropha curcas].

OBJECTIVE: To determine the chemical constituents of Jatropha curcas. METHOD: Chemical constituents were obtained using various chromatography methods including silica gel column chromatography and HPLC. The structures of isolated compounds were determined by spectroscopic methods including 1H-NMR, 13C-NMR and MS. RESULT AND CONCLUSION: Fourteen phenolic compounds were obtained from the stems of J. curcas and their structures were identified to be 5,4'-dihydroxy-3, 7, 3'-trimethoxyflavone (1), 5, 3', 4'-trihydroxy-3,7-dimethoxyflavone (2), 3-O-methylquercetin (3), 5, 6, 7-trimethoxycoumarin (4), tomentin (5), isoscopoletin (6), omega-hydroxypropioquaiacone (7), coniferaldehyde (8), 3, 5-dihydroxy-4-methoxybenzaldehyde (9), vanillic acid (10), isovanillin (11), 4-hydroxybenzaldehyde (12), cimifugin (13) and (E)-3-hydroxy-5-methoxy-stilbene (14). Among them, compounds 1-4 and 6-14 were isolated from the genus of Jatropha for the first time.

A new chromene isolated from Ageratum conyzoides.

From the ethanol extract of the whole plant of Ageratum conyzoides L. (Compositae), one new chromene, 2,2-dimethylchromene 7-methoxy-6-O-beta-D-glucopyranoside, was isolated, together with thirteen known compounds, seven of which were being reported for the first time. The compounds were all characterized by MS, IR, 1D- and 2D-NMR spectroscopy. 7,3',5'-Tri-O-methyltricetin (7), precocene II (9), 3,5,7,4'-tetrahydroxyflavone (13) and 5,6,7,3',4',5'-hexamethoxyflavone (14) exhibited inhibitory activity on the P-388 cancer cell line with IC50 values of 12.8, 24.8, 3.5 and 7.8 microM respectively, while compound 9 exhibited inhibitory activity on the HT-29 cancer cell line with an IC50 value of 61 microM; the others showed no significant cytotoxic activity on the cell lines tested.

[Chemical constituents from petroleum ether fraction of ethanol extract of Acorus tatarinowii].

The petroleum ether fraction of ethanol extract of Acorus tatarinowii were separated by column chromatography and recrystallization to afford seven compounds. On the spectroscopic analysis, they were identified as 1-hydroxy-7(11),9-guaiadien-8-one (1), calamenone(2), cis-asarone(3), chrysophanol (4), physcion (5), emodin (6), (+)-galbacin (7). Compound 1 is a new compound. Compounds 4-7 were isolated from this plant for the first time.

[Studies on chemical constituents in fruit of Alpinia oxyphylla].

OBJECTIVE: To study the chemical constituents in fruit of Alpinia oxyphylla and their cytotoxicities on cancer cell lines. METHOD: Compounds were isolated and purified by various column chromatographic methods. Their structures were determined by physico-chemical properties and spectral analyses. Compound cytotoxicity was assessed by the sulforhodamine B (SRB) assay. RESULT: Eight compounds were obtained from Me2CO-H2O (70%) extract of the fruit of A. oxyphylla and their structures were identified as: (9E)-humulene-2, 3; 6, 7-diepoxide (1), 3(12), 7(13), 9(E)-humulatriene-2, 6-diol (2), (-)-oplopanone (3), yakuchinone A (4), yakuchinone B (5), tectochrysin (6), isovanillin (7), (2E, 4E)-6-hydroxy-2, 6-dimethylhepta-2, 4-dienal (8), and the cytotoxicities of compounds 1, 3-5 on cancer cell lines, A549, HT-29 and SGC-7901, were also investigated. CONCLUSION: Compounds 1-3, 7, 8 were isolated for the first time from this genus and compounds 1, 3-5 exhibited no cytotoxicity against three cancer cell lines at a concentration of 10 mg x L(-1).

Two new biphenanthrenes with cytotoxic activity from Bulbophyllum odoratissimum.

Two new dimeric phenanthrenes, bulbophythrins A (1) and B (2), were isolated from Bulbophyllum odoratissimum. Their structures were elucidated by HR-ESI-MS, 1D and 2DNMR spectroscopy. They were evaluated in vitro for their inhibitory ability against the growth of human leukemia cell lines K562 and HL-60, human lung adenocarcinoma A549, human hepatoma BEL-7402 and human stomach cancer SGC-7901. Both compounds showed significant cytotoxicity against the tested cell lines. Compound 1 exhibited some selectivity against HL-60 and BEL-7402 with IC(50) values of 1.27 x 10(-3) and 1.22 x 10(-3) micromol/ml respectively, whereas 2 was most active against A549 with IC(50) value of 1.18 x 10(-3) micromol/ml.