Publications by authors named "Jiajia Meng"

31 Publications

Assessment of Human Exposure to Five Mycotoxins in China by Biomonitoring Approach.

Toxins (Basel) 2021 Oct 28;13(11). Epub 2021 Oct 28.

Key Laboratory of Protected Horticultural Technology, Institute for Agro-Food Standards and Testing Technology, Academy of Agricultural Sciences, Shanghai 201403, China.

This biomonitoring study was conducted to investigate the concentration levels of five mycotoxins in urine samples from 269 healthy volunteers living in the Yangtze River Delta, China. Alternariol (AOH), alternariol monomethyl ether (AME), tenuazonic acid (TeA) and tentoxin (TEN) were detected in 38.3%, 48.7%, 63.9% and 23.4% of urine samples with the concentrations ranging from 0.057 to 45.8 ng/mL, 0.020 to 0.802 ng/mL, 0.050 to 80.6 ng/mL and 0.021 to 0.939 ng/mL, respectively. Altenuene (ALT) was not detected in any urine sample. Based on the urinary concentrations, the probable daily intake (PDI) values of mycotoxins were calculated, and 100%, 99.2-100%, 0.372% and 1.12% of participants exceeded the threshold of toxicological concern (TTC) values for AOH, AME, TeA and TEN, respectively. This study revealed high potential health risks related to the contaminations of major mycotoxins in China and highlighted the necessity for more toxicological studies to provide better basis for further comprehensive risk assessments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins13110762DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8625692PMC
October 2021

Production of Toxins in Yellow Peach () upon Artificial Inoculation with .

Toxins (Basel) 2021 09 15;13(9). Epub 2021 Sep 15.

Institute for Agro-Food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.

The yellow peach (), an important fruit in China, is highly susceptible to infection by sp., leading to potential health risks and economic losses. In the current study, firstly, yellow peaches were artificially inoculated with . Then, the fruits were stored at 4 °C and 28 °C to simulate the current storage conditions that consumers use, and the toxins (ATs) contents from different parts of the fruits were analyzed via ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The results showed that the growth of . and the ATs production were dramatically affected by the storage temperature. At 28 °C, the fungi grew rapidly and the lesion diameter reached about 4.0 cm within 15 days of inoculation, while, at 4 °C, the fungal growth was noticeably inhibited, with no significant change in the lesion diameter. To our surprise, high contents of ATs were produced under both storage conditions even though the fungal growth was suppressed. With an increase in the incubation time, the amounts of ATs showed a steady tendency to increase in most cases. Remarkably, alternariol monomethyl ether (AME), alternariol (AOH), and tenuazonic acid (TeA) were detected in the rotten tissue and also in the surrounding tissue, while a large amount of TeA could also be found in the healthy tissue. To the best of our knowledge, this is the first report regarding the production of ATs by the infection of sp. in yellow peach fruits via artificial inoculation under regulated conditions, and, based on the evidence herein, it is recommended that ATs be included in monitoring and control programs of yellow peach management and food safety administration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins13090656DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8473313PMC
September 2021

CuWO Nanodots for NIR-Induced Photodynamic and Chemodynamic Synergistic Therapy.

ACS Appl Mater Interfaces 2021 May 6;13(19):22150-22158. Epub 2021 May 6.

Beijing Engineering Research Center of Mixed Reality and Advanced Display, School of Optoelectronics, Beijing Institute of Technology, Beijing 100081, China.

Dynamic therapy, such as photodynamic therapy (PDT) or chemodynamic therapy (CDT), is one of the most promising therapeutic strategies for tumors. Integrating the advantages of near-infrared-induced PDT and CDT can potentially improve the therapeutic performance. A single primitive nanostructure, CuWO nanodots, was developed. It could generate reactive oxygen species under 808 nm light irradiation and release copper ions into the acid tumor microenvironment, thereby boosting Fenton-like reactions. The PDT and CDT would occur when the nanodots were introduced into the tumor tissue and irradiated under 808 nm light. The results of combined PDT and CDT antitumor studies showed the effective inhibition of tumor tissue growth, thereby suggesting that the nanodots are candidate agents for synergistic antitumor applications.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.1c00970DOI Listing
May 2021

Exposure Assessment of Multiple Mycotoxins and Cumulative Health Risk Assessment: A Biomonitoring-Based Study in the Yangtze River Delta, China.

Toxins (Basel) 2021 02 1;13(2). Epub 2021 Feb 1.

Institute for Agro-Food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.

The extensive exposure to multiple mycotoxins has been demonstrated in many countries; however, realistic assessments of the risks related to cumulative exposure are limited. This biomonitoring study was conducted to investigate exposure to 23 mycotoxins/metabolites and their determinants in 227 adults (aged 20-88 years) in the Yangtze River Delta, China. Eight mycotoxins were detected in 110 urine samples, and multiple mycotoxins co-occurred in 51/227 (22.47%) of urine samples, with deoxynivalenol (DON), fumonisin B1 (FB1), and zearalenone (ZEN) being the most frequently occurring. For single mycotoxin risk assessment, FB1, ZEN, aflatoxin B1 (AFB1), and ochratoxin A (OTA) all showed potential adverse effects. However, for the 12 samples containing DON and ZEN, in which none had a hazard risk, the combination of both mycotoxins in two samples was considered to pose potential endocrine disrupting risks to humans by hazard index (HI) method. The combined margin of exposure (MOE) for AFB1 and FB1 could constitute a potential health concern, and AFB1 was the main contributor. Our approach provides a blueprint for evaluating the cumulative risks related to different types of mycotoxins and opens a new horizon for the accurate interpretation of epidemiological health outcomes related to multi-mycotoxin exposure.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins13020103DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7912756PMC
February 2021

Aromatase inhibitors plus ovarian function suppression versus tamoxifen plus ovarian function suppression for premenopausal women with early stage breast cancer: a systematic review and meta-analysis.

Ann Palliat Med 2020 Jul 20;9(4):2294-2302. Epub 2020 May 20.

Department of Oncology, Affiliated Zhongshan Hospital of Dalian University, Dalian, China.

In the NCCN guidelines version 1.2019, aromatase inhibitors (AIs) or tamoxifen (TAM) for 5 years plus ovarian function suppression (OFS) were recommended for premenopausal breast cancer patient who has higher risk of recurrence. The meta-analysis established a comparison of the curative effect of two adjuvant endocrine therapies. In order to obtain randomized controlled trials (RCTs) related to this metaanalysis, PubMed and Embase database were searched systematically in English during May 2019. Two reviewers screened the articles and extracted data based on the criteria recommended by the Cochrane collaboration for evaluating evidence in RCTs. The first outcome was disease-free survival (DFS). Overall survival (OS) was the other endpoint. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled utilizing fixed-effect model. The heterogeneity of this study has been described by Cochran's Q and the I2 statistics. Three RCTs which involved 7,203 premenopausal women with breast cancer were available in this meta-analysis. Pooled HRs showed that there was not difference between AIs plus OFS and TAM plus OFS in DFS (HR =0.87, 95% CI: 0.66-1.14, P=0.30). No statistical differences were found in OS between the two adjuvant therapies (HR =1.22, 95% CI: 0.75-1.99, P=0.43). Based on the included studies, there were no statistical differences between AIs plus OFS and TAM plus OFS in DFS and OS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/apm-20-488ADOI Listing
July 2020

Dual-target electrochemical aptasensor based on co-reduced molybdenum disulfide and Au NPs (rMoS-Au) for multiplex detection of mycotoxins.

Biosens Bioelectron 2020 Feb 15;150:111894. Epub 2019 Nov 15.

Institute for Agro-food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-products (Shanghai), Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, Shanghai, 201403, China. Electronic address:

Multiple mycotoxin contamination has posed health risks in the area of food safety. In this study, co-reduced molybdenum disulfide and gold nanoparticles (rMoS-Au) were designed and used for the first time as an efficient platform endowing electrochemical electrodes with superior electron transfer rates, large surface areas and strong abilities to firmly couple with large amounts of different aptamers. After further modification with thionine (Thi) and 6-(Ferrocenyl) hexanethiol (FC6S), a platform enabling sensitive, selective and simultaneous determination of two important mycotoxins, zearalenone (ZEN) and fumonisin B1 (FB1), was achieved. The established aptasensor showed excellent linear relationships (R > 0.99) when ZEN and FB1 concentrations were in the range of 1 × 10-10 ng mL and 1 × 10-1 × 10 ng mL, respectively. High sensitivity of ZEN and FB1 with a limit of detection as low as 5 × 10 ng mL was obtained with excellent selectivity and stability. The effectiveness of the aptasensor was verified in real maize samples, and satisfactory recoveries were attained. The established platform could be easily expanded to other aptamer-based multiplex screening protocols in biochemical research and clinical diagnosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bios.2019.111894DOI Listing
February 2020

sp. nov., isolated from faeces of .

Int J Syst Evol Microbiol 2020 Jan;70(1):11-15

State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Changping, Beijing 102206, PR China.

Two novel strains (HT111-2 and HT170-2) of the genus were isolated from faecal samples collected on the Qinghai-Tibet Plateau, PR China. The isolates were Gram-stain-positive, rod-shaped, non-spore-forming bacteria with irregular circular colonies. Phylogenetic analysis and comparison of the 16S rRNA gene sequences demonstrated that the two strains form a subcluster and are closest to JCM 6256 (97.3 %) and DSM 11664 (97.2 %). Phylogenetic analysis of two housekeeping genes ( and ) found that strains HT111-2 and HT170-2 had the same closest relatives as the 16S rRNA gene sequence analysis did. The G+C content of strains HT111-2 and HT170-2 were 38.8 mol%. The values of DNA-DNA hybridization with known species were lower than the threshold (70%). Average nucleotide identity values of strain HT111-2 with JCM 6256 and DSM 11664 were 77.84 % and 76.85 %, respectively. The major fatty acids of strains HT111-2 and HT170-2 were C, Cω and C. Results of phenotypic, chemotaxonomic and phylogenetic analyses suggest strains HT111-2 and HT170-2 represent a novel species of the genus , for which the name sp. nov. is proposed with HT111-2 (=CGMCC 1.13855=KCTC 15803) as the type strain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1099/ijsem.0.003598DOI Listing
January 2020

sp. nov., isolated from (Tibetan wild ass) faeces.

Int J Syst Evol Microbiol 2019 Nov;69(11):3629-3635

Shanghai Institute for Emerging and Re-emerging Infectious Diseases, Shanghai Public Health Clinical Center, Shanghai 201508, PR China.

Two Gram-stain-positive, irregular rod-shaped (0.2-0.5×1.3-2.5 um) strains, HY056 and HY057, were isolated from the faeces of (the largest of the wild asses) collected at different regions from the Qinghai-Tibetan Plateau of PR China. Phylogenetic analyses indicated that strains HY056 and HY057 belong to the genus by sharing a similarity ranging from 96.3 to 97.0 % in the 16S rRNA gene sequence and forming a distinct cluster with JCM 16608, 78, Ka25 and XZ17. The digital DNA-DNA hybridization value of strain HY056 was 96.9 % with strain HY057, but less than 30.0 % with the above four closest relatives. MK-8(H) was the predominant (91.6 %) respiratory quinone. The cell wall contained ll-2,6-diaminopimelic acid as the diamino acid of the peptidoglycan. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phospholipid. The predominant fatty acids (>10.0 %) were Cω9 and -C The DNA G+C contents of strains HY056 and HY057 were 68.9 and 69.1 mol%, respectively. -Glucosidase expression was positive, and acid was produced from d-fructose. Strain HY056 (=CGMCC 4.7563=JCM 33399) is assigned as the type strain of a novel species within the genus , for which the name sp. nov is proposed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1099/ijsem.0.003674DOI Listing
November 2019

Ustilaginoidin M, a new bis-naphtho-γ-pyrone from the fungus .

Nat Prod Res 2021 May 12;35(9):1555-1560. Epub 2019 Aug 12.

Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China.

Ustilaginoidin M (), a novel bis-naphtho-γ-pyrone, was isolated from the cultures of the fungus which was the pathogen of rice false smut disease. Its structure was elucidated by spectroscopic analysis and by comparison of its physical and spectroscopic data with the literature. Compound was tested for its cytotoxicity against five human cancer cell lines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/14786419.2019.1652289DOI Listing
May 2021

Sorbicillinoids From the Fungus and Their Phytotoxic, Cytotoxic, and Antimicrobial Activities.

Front Chem 2019 12;7:435. Epub 2019 Jun 12.

Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing, China.

, the causal fungus of rice false smut, was found in previous studies to produce two types of metabolites, ustiloxins and ustilaginoidins. However, genome sequencing of revealed a plethora of secondary-metabolites-biosynthetic core genes that were capable to biosynthesize unreported metabolites. A large-scale fermentation of was thus performed, and the fungal extract was chemically re-investigated. After removing the known metabolites, we found a fraction containing unknown phytotoxic substances. Fractionation of this part has led to the isolation of six new sorbicillinoids, namely ustisorbicillinols A~F (~), and two new sorbicillinoid-related pyrones, named ustilopyrones A () and B (), together with nine known cogeners (~). The structures of the new compounds were elucidated by analysis of their NMR, HRMS, and CD spectra, while ECD, C NMR and optical rotation calculations were additionally used for configurational assignments. Plausible biosynthetic pathways for the new compounds were proposed. Phytotoxicity assays revealed that the major sorbicillinoids (~, and ) showed strong inhibition against the radicle and germ elongation of rice and lettuce seeds, with compound displaying the strongest inhibition. The isolated compounds were also evaluated for their cytotoxic, antibacterial, and antifungal activities. Compounds , and ~ showed moderate cytotoxicities against the tested cell lines with ICs of 8.83~74.7 μM. Compounds , and ~ were active against the tested bacteria (MICs 4~128 μg/mL), while compounds ~ displayed moderate antifungal activities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fchem.2019.00435DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6582230PMC
June 2019

Determination of multiple mycotoxins in paired plasma and urine samples to assess human exposure in Nanjing, China.

Environ Pollut 2019 May 1;248:865-873. Epub 2019 Mar 1.

Institute for Agro-food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai Academy of Agricultural Sciences, Shanghai, 201403, China. Electronic address:

This study was conducted to investigate mycotoxin exposure in 260 rural residents (age 18-66 years) in Nanjing, China. Paired plasma and first morning urine samples were analyzed for 26 mycotoxin biomarkers, including 12 parent mycotoxins and 14 mycotoxin metabolites, by an ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method. Mycotoxins and their metabolites were detected in 95/260 (36.5%) plasma samples and 144/260 (55.4%) urine samples. The most prevalent mycotoxin in plasma was ochratoxin A (OTA), with the incidence of 27.7% (range 0.312-9.18 μg/L), while aflatoxin B-lysine (AFB-lysine) (incidence 19.6%, range 10.5-74.5 pg/mg albumin), fumonisin B (FB) (incidence 2.7%, range 0.305-0.993 μg/L), deoxynivalenol (DON) (incidence 2.3%, range 1.39-5.53 μg/L), zearalenone (ZEN) (incidence 6.5%, range 0.063-0.418 μg/L) and zearalanone (ZAN) (incidence 1.2%, range 0.164-0.346 μg/L) were also detected in plasma samples. Deoxynivalenol-15-glucuronide (DON-15-GlcA) was the most frequently detected urinary mycotoxin, with the incidence of 43.8% (range 0.828-37.7 μg/L). DON (incidence 10.0%, range 1.39-14.7 μg/L), DON-3-glucuronide (DON-3-GlcA) (incidence 15.8%, range 0.583-5.84 μg/L), aflatoxin M (AFM) (incidence 10.4%, range 0.125-0.464 μg/L), ZAN (incidence 7.7%, range 0.106-1.82 μg/L), ZEN (incidence 6.9%, range 0.056-0.311 μg/L), FB (incidence 3.1%, range 0.230-1.33 μg/L), T-2 toxin (incidence 2.3%, range 0.248-3.61 μg/L) and OTA (incidence 1.2%, range 0.153-0.557 μg/L) were also found in urine samples. Based on the plasma or urinary levels, the daily intakes of AFB, FB, ZEN, DON and OTA were estimated. The results showed that the investigated rural dwellers were exposed to multiple mycotoxins, especially to carcinogenic mycotoxin AFB with a mean daily intake of 0.41 μg/kg·bw/day, thereby underlining a potential public health concern. To the best of our knowledge, this is the first study to evaluate human exposure to mycotoxins with direct measurements of multiple mycotoxins in paired plasma and urine samples for over 200 subjects of a single population.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.envpol.2019.02.091DOI Listing
May 2019

A systematic review of plant-conjugated masked mycotoxins: Occurrence, toxicology, and metabolism.

Crit Rev Food Sci Nutr 2020 26;60(9):1523-1537. Epub 2019 Feb 26.

Institute for Agro-food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai Academy of Agricultural Sciences, Shanghai, China.

Masked mycotoxins are biologically modified phase II metabolites formed by plant defense mechanisms through glucosylation catalyzed by uridine diphosphate -glucosyltransferases. Most of the current reports focus on the occurrence of masked mycotoxins in Europe, America, Africa, and cover other geographic regions, e.g. China and Japan. High proportions of masked mycotoxins co-occurring with their parent forms in various cereal-based food and feedstuff could clearly increase total exposures and pose additional health risks to humans and animals. In contrast to the parent mycotoxins, the data on the toxicity of masked mycotoxins are still scarce, however, the poor existing information showed that masked mycotoxins generally exhibit significant toxicities lower than those of their parent forms, especially for deoxynivalenol-3-glucoside, which is the only thoroughly investigated masked mycotoxin. Although the lower toxicity level of masked mycotoxins, these are probably hydrolyzed into their free forms by intestinal microorganisms in the digestive tract of mammals and thus contribute to unpredicted toxicity. The metabolic characteristics of reported masked mycotoxins are species-specific. The most relevant animal model of human sensitivity, the pig, is most sensitive to masked mycotoxins. This review focuses on updates in the current knowledge on country-specific natural-occurrence data in global surveys, as well as and toxicology and metabolic investigations of masked mycotoxins.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/10408398.2019.1578944DOI Listing
April 2020

Molecularly Imprinted Poly(thionine)-Based Electrochemical Sensing Platform for Fast and Selective Ultratrace Determination of Patulin.

Anal Chem 2019 03 6;91(6):4116-4123. Epub 2019 Mar 6.

Institute for Agro-food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-products (Shanghai), Ministry of Agriculture , Shanghai Academy of Agricultural Sciences , 1000 Jingqi Road , Shanghai 201403 , P. R. China.

An innovative approach based on a surface functional monomer-directing strategy for the construction of a sensitive and selective molecularly imprinted electrochemical sensor for patulin recognition is described. A patulin imprinted platinum nanoparticle (PtNP)-coated poly(thionine) film was grown on a preformed thionine tailed surface of PtNP-nitrogen-doped graphene (NGE) by electropolymerization, which provided high capacity and fast kinetics to uptake patulin molecules. Thionine acted not only as a functional monomer for molecularly imprinted polymer (MIP), but also as a signal indicator. Enhanced sensitivity was obtained by combining the excellent electric conductivity of PtNPs, NGE, and thionine with multisignal amplification. The designed sensor displayed excellent performance for patulin detection over the range of 0.002-2 ng mL (R = 0.995) with a detection limit of 0.001 ng mL for patulin. In addition, the resulting sensor showed good stability and high repeatability and selectivity. Furthermore, the feasibility of its applications has also been demonstrated in the analysis of real samples, providing novel tactics for the rational design of MIP-based electrochemical sensors to detect a growing number of deleterious substances.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.analchem.8b05791DOI Listing
March 2019

Ustilobisorbicillinol A, a Cytotoxic Sorbyl-Containing Aromatic Polyketide from Ustilaginoidea virens.

Org Lett 2019 03 20;21(5):1311-1314. Epub 2019 Feb 20.

Department of Plant Pathology, College of Plant Protection , China Agricultural University , Beijing 100193 , China.

Ustilobisorbicillinol A (1), which is a novel bisorbicillinoid featuring a unique cage structure that incorporates one sorbicillinol and one sorbyl-containing phenanthrenone unit, was isolated from the culture of Ustilaginoidea virens. Three biogenetically related new metabolites (2-4) were also isolated. Their structures were elucidated by extensive spectroscopic analyses, including the C NMR and electronic circular dichroism (ECD) calculations for the configurational assignment. The biosynthetic pathway for these sorbyl-containing polyketides was proposed. Compound 1 showed pronounced cytotoxicity, and it induced significant cell cycle arrest and apoptosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.orglett.8b04101DOI Listing
March 2019

Determination of the absolute configurations of the stereogenic centers of ustilaginoidins by studying the biosynthetic monomers from a gene knockout mutant of Villosiclava virens.

Sci Rep 2019 02 12;9(1):1855. Epub 2019 Feb 12.

Department of Plant Pathology, College of Plant Protection, Northwest A&F University, Yangling, 712100, China.

Ustilaginoidins are a kind of mycotoxins with 9,9'-linked bis-naphtho-γ-pyrones structures produced by the rice false smut pathogen Villosiclava virens. These metabolites displayed a wide range of bioactivities, such as teratogenic, cytotoxic, phytotoxic, and antibacterial activities. So far 26 ustilaginoidins have been isolated from V. virens, among which 18 compounds contained stereogenic center(s), however, most of them were unknown for the absolute configurations, except that of ustilaginoidin D. In this study, the absolute structures of these ustilaginoidins were constructed for the first time by analysis of the biosynthetic monomers obtained from a gene knockout mutant (ΔUV_2091) of V. virens. The gene UV_2091 was predicted to encode an enzyme that dimerized the monomeric naphtho-γ-pyrones in V. virens. Knockout of this gene led to the accumulation of three monomers, namely hemiustilaginoidin F (1), epihemiustilaginoidin D (2), and hemiustilaginoidin D (3), but the production of ustilaginoidins was completely blocked. The structures of the monomers were deduced by spectroscopic analysis, in combination with TDDFT ECD calculations for determining the absolute configurations. These compounds were tested for their phytotoxic, cytotoxic, antibacterial, and antifungal activities. Compounds 1 and 3 showed inhibition against the radicle and plumule elongation of rice and lettuce seeds at the tested concentrations. Compound 1 was active against the tested five human cancer cells, with half maximal inhibitory concentrations (ICs) of 13.2~37.3 μM. Compounds 1~3 inhibited the growth of the tested pathogenic bacteria with minimum inhibitory concentrations of 8~32 µg/mL, while compound 3 exhibited antifungal activity against Magnaporthe oryzae (IC, 5.21 µg/mL). A comparison of these data with those of the ustilaginoidins provided insights into the structure-bioactivity relationships.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-37941-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6372653PMC
February 2019

Development of a QuEChERS-Based UHPLC-MS/MS Method for Simultaneous Determination of Six Toxins in Grapes.

Toxins (Basel) 2019 02 1;11(2). Epub 2019 Feb 1.

Institute for Agro-food Standards and Testing Technology, Shanghai Key Laboratory of Protected Horticultural Technology, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.

A simple and reliable analytical method for the simultaneous determination of alternariol (AOH), altenuene (ALT), tentoxin (TEN), altenusin (ALS), tenuazonic acid (TeA), and alternariol monomethyl ether (AME) in grapes was developed by ultra-high-performance liquid chromatography⁻tandem mass spectrometry (UHPLC-MS/MS). A modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure with the extraction by acetonitrile and purification by sodium chloride (0.5 g) and anhydrous magnesium sulfate (0.5 g) was established to recover the six toxins. After validation by determining the linearity (² > 0.99), recovery (77.8⁻101.6%), sensitivity (limit of detection in the range of 0.03⁻0.21 μg kg, and limit of quantification in the range of 0.09⁻0.48 μg kg), and precision (relative standard deviation (RSD) ≤ 12.9%), the analytical method was successfully applied to reveal the contamination state of toxins in grapes. Among 56 grape samples, 40 (incidence of 71.4%) were contaminated with toxins. TEN was the most frequently found mycotoxin (37.5%), with a concentration range of 0.10⁻1.64 μg kg, followed by TeA (28.6%) and AOH (26.8%). ALT (10.7%), AME (3.6%), and ALS (5.4%) were also detected in some samples. To the best of our knowledge, this is the first report about the toxins contamination in grapes in China.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins11020087DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6410285PMC
February 2019

RD-Metabolizer: an integrated and reaction types extensive approach to predict metabolic sites and metabolites of drug-like molecules.

Chem Cent J 2017 Jul 18;11(1):65. Epub 2017 Jul 18.

State Key Laboratory of Bioreactor Engineering, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China.

Background: Experimental approaches for determining the metabolic properties of the drug candidates are usually expensive, time-consuming and labor intensive. There is a great deal of interest in developing computational methods to accurately and efficiently predict the metabolic decomposition of drug-like molecules, which can provide decisive support and guidance for experimentalists.

Results: Here, we developed an integrated, low false positive and reaction types extensive metabolism prediction approach called RD-Metabolizer (Reaction Database-based Metabolizer). RD-Metabolizer firstly employed the detailed reaction SMARTS patterns to encode different metabolism reaction types with the aim of covering larger chemical reaction space. 2D fingerprint similarity calculation model was built to calculate the metabolic probability of each site in a molecule. RDKit was utilized to act on pre-written reaction SMARTS patterns to correct the metabolic ranking of each site in a molecule generated by the 2D fingerprint similarity calculation model as well as generate corresponding structures of metabolites, thus helping to reduce the false positive metabolites. Two test sets were adopted to evaluate the performance of RD-Metabolizer in predicting SOMs and structures of metabolites. The results indicated that RD-Metabolizer was better than or at least as good as several widely used SOMs prediction methods. Besides, the number of false positive metabolites was obviously reduced compared with MetaPrint2D-React.

Conclusions: The accuracy and efficiency of RD-Metabolizer was further illustrated by a metabolism prediction case of AZD9291, which is a mutant-selective EGFR inhibitor. RD-Metabolizer will serve as a useful toolkit for the early metabolic properties assessment of drug-like molecules at the preclinical stage of drug discovery. Graphical abstract A visual example of the metabolic site and the corresponding metabolite of Chloroquine predicted by RD-Metabolizer.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13065-017-0290-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5515729PMC
July 2017

New Ustilaginoidins from Rice False Smut Balls Caused by Villosiclava virens and Their Phytotoxic and Cytotoxic Activities.

J Agric Food Chem 2017 Jun 14;65(25):5151-5160. Epub 2017 Jun 14.

Key Laboratory of Pest Monitoring and Green Management of Ministry of Agriculture, Department of Plant Pathology, College of Plant Protection, China Agricultural University , Beijing 100193, People's Republic of China.

Ustilaginoidins are a class of bis-naphtho-γ-pyrones, typically produced by Villosiclava virens, the pathogen of the rice false smut (RFS), which has been one of the most destructive rice fungal diseases. Previously, we found that ustilaginoidins identified from the culture of V. virens on rice medium were less polar than those reported from the RFS balls in general. In this study, we reinvestigated the high-performance liquid chromatography with diode array detection and high-resolution mass spectrometry (HPLC-DAD-HRMS) profile of the ethyl acetate (EtOAc) extract of the RFS balls and found several interesting peaks that correspond to new ustilaginoidins. As a result, eight new and polar congeners, named ustilaginoidins Q-T (1-4), 2,3-dihydroustilaginoidin T (5), and ustilaginoidins U-W (6-8), were isolated. In addition, 17 known ustilaginoidins, including ustilaginoidins K-N (9-12), ustilaginoidin P (13), ustilaginoidin E (14), isochaetochromin B (15), and ustilaginoidins A-J (16-25), were re-isolated. The structures of the new compounds were elucidated by comprehensive analysis of the spectroscopic data. Ustilaginoidins Q (1) and R (2) feature an uncommon 2-hydroxypropyl-substituted skeleton and biogenetically incorporate one more acetate unit than common ustilaginoidins. Ustilaginoidin W (8) is a rare formate-containing bis-naphtho-γ-pyrone. Ustilaginoidins R (2), U (6), B (17), and I (24) showed moderate inhibitory activities toward the radicle or germ elongation of rice seeds. Ustilaginoidins R (2), S (3), V (7), W (8), B (17), C (18), and H-J (23-25) were cytotoxic to the tested human cancer cell lines (HCT116, NCI-H1650, BGC823, Daoy, and HepG2), with IC values in the range of 4.06-44.1 μM.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jafc.7b01791DOI Listing
June 2017

Development of Colloidal Gold-Based Lateral Flow Immunoassay for Rapid Qualitative and SemiQuantitative Analysis of Ustiloxins A and B in Rice Samples.

Toxins (Basel) 2017 02 24;9(3). Epub 2017 Feb 24.

Department of Crop Physiology and Cultivation, College of Agronomy and Biotechnology, Beijing 100193, China.

Rice false smut is a worldwide devastating rice disease infected by the fungal pathogen Villosiclava virens. Ustiloxin A (UA) and ustiloxin B (UB), cyclopeptide mycotoxins, were the major ustiloxins isolated from the rice false smut balls (FSBs) that formed in the pathogen-infected rice spikelets. Based on the specific monoclonal antibodies (mAbs) 2D3G5 and 1B5A10, respectively, against UA and UB, the lateral flow immunoassays (LFIAs) were developed, and the indicator ranges for UA and UB both were 50-100 ng/mL. The cross-reactivities of UB for UA LFIA, and UA for UB LFIA were 5% and 20%, respectively, which were consistent with the icELISA results reported previously. Even at 50,000 ng/mL, none of other commonly existent metabolites in rice samples caused noticeable inhibition. The LFIAs were used for determination of UA and UB contents in rice FSBs and rice grains, and the results were agreeable with those by HPLC and icELISA. There was no change in the sensitivity of either dipstick stored at 4 °C) after at least three months. The developed LFIA has specificity and sensitivity for detecting UA and UB as well as simplicity to use. It will be a potential point-of-care device for rapid evaluation of the rice samples contaminated by UA and UB.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins9030079DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5371834PMC
February 2017

Dibenzo-α-pyrones: a new class of larvicidal metabolites against Aedes aegypti from the endophytic fungus Hyalodendriella sp. Ponipodef12.

Pest Manag Sci 2017 Jul 5;73(7):1478-1485. Epub 2017 Jan 5.

Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing, China.

Background: In our search for new agrochemicals from endophytic fungi, the crude extract of the endophytic Hyalodendriella sp. Ponipodef12 associated with the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L. was found to possess larvicidal activity against Aedes aegypti.

Results: Fractionation of the extract has led to the isolation of 11 dibenzo-α-pyrones (1-11), including three new congeners: hyalodendriols A-C (1-3). The structures of the new compounds were elucidated by comprehensive spectroscopic analyses, including the modified Mosher's method for the assignment of the absolute configuration. Compounds 2-7 showed potent larvicidal activities against the fourth-instar larvae of A. aegypti with IC values ranging from 7.21 to 120.81 µg mL . Among them, penicilliumolide D (6) displayed the strongest activity (IC = 7.21 µg mL ). A structure-larvicidal activity relationship was discussed. The possible mode of action of these compounds was assessed for their acetylcholinesterase inhibitory activities. In addition, hyalodendriol C (3) displayed antibacterial activity against Bacillus subtilis and Xanthomonas vesicatoria, and exhibited strong inhibition against the spore germination of Magnaporthe oryzae.

Conclusion: Our study revealed dibenzo-α-pyrones to be a new class of larvicidal metabolites against A. aegypti. © 2016 Society of Chemical Industry.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ps.4481DOI Listing
July 2017

The Contents of Ustiloxins A and B along with Their Distribution in Rice False Smut Balls.

Toxins (Basel) 2016 09 6;8(9). Epub 2016 Sep 6.

Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China.

Ustiloxins are cyclopeptide mycotoxins isolated from rice false smut balls (FSBs), the ball-like colonies transformed from the individual grains through the filament infection by the fungal pathogen Villosiclava virens. There were no obvious relations between ustiloxin content and any of the collection areas, collection times, or average weight of each FSB. The rice false smut balls at early, middle, and late maturity stages were respectively divided into different parts (glume, chlamydospores, mycelia, and pseudoparenchyma). The highest content of ustiloxins A and B of rice FSBs was found at the early maturity stage. Both ustiloxins A and B were mainly distributed in the middle layer containing mycelia and immature chlamydospores of the FSBs. When the rice FSBs were at the early maturity stage, the total yield of ustiloxins A and B in the middle layer of each ball was 48.3 µg, which was 3.20-fold of the yield (15.1 µg) of the inner part of the ball. The rice FSBs at the early maturity stage are the appropriate materials for the production of ustiloxins A and B.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins8090262DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5037488PMC
September 2016

Discovery of peptide inhibitors targeting human programmed death 1 (PD-1) receptor.

Oncotarget 2016 Oct;7(40):64967-64976

State Key Laboratory of Bioreactor Engineering, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, 200237, China.

Blocking the interaction of human programmed death 1 (hPD-1) and its ligand hPD-L1 has been a promising immunotherapy in cancer treatment. In this paper, using a computational de novo peptide design method, we designed several hPD-1 binding peptides. The most potent peptide Ar5Y_4 showed a KD value of 1.38 ± 0.39 μM, comparable to the binding affinity of the cognate hPD-L1. A Surface Plasmon Resonance (SPR) competitive binding assay result indicated that Ar5Y_4 could inhibit the interaction of hPD-1/hPD-L1. Moreover, Ar5Y_4 could restore the function of Jurkat T cells which had been suppressed by stimulated HCT116 cells. Peptides described in this paper provide promising biologic candidates for cancer immunotherapy or diagnostics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.18632/oncotarget.11274DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5323130PMC
October 2016

Sorbicillinoids from Fungi and Their Bioactivities.

Molecules 2016 Jun 1;21(6). Epub 2016 Jun 1.

Key Laboratory of Plant Pathology, Ministry of Agriculture/Department of Plant Pathology, College of Plant Protection, China Agricultural University, Beijing 100193, China.

Sorbicillinoids are important hexaketide metabolites derived from fungi. They have a variety of biological activities including cytotoxic, antioxidant, antiviral and antimicrobial activity. The unique structural features of the sorbicillinoids make them attractive candidates for developing new pharmaceutical and agrochemical agents. About 90 sorbicillinoids have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, structures, and biological activities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules21060715DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273499PMC
June 2016

Preparative Separation of Main Ustilaginoidins from Rice False Smut Balls by High-Speed Counter-Current Chromatography.

Toxins (Basel) 2016 Jan 12;8(1). Epub 2016 Jan 12.

Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing, Ministry of Agriculture, Beijing 100193, China.

Ustilaginoidins are bis-naphtho-γ-pyrone mycotoxins isolated from the rice false smut balls (FSBs) infected by the pathogen Villosiclava virens in rice spikelets on panicles. In order to obtain large amounts of pure ustilaginoidins to further evaluate their biological activities and functions, phytotoxicity on rice, security to human and animals as well as to accelerate their applications as pharmaceuticals, preparative high-speed counter-current chromatography (HSCCC) was successfully applied to the isolation and purification of seven bis-naphtho-γ-pyrone mycotoxins, namely ustilaginoidins A (1), G (2), B (3), H (4), I (5), C (6), and J (7) from the ethyl acetate crude extract of rice FSBs. Both 1 and 2 were prepared by HSCCC from the low-polarity fraction of the crude extract using the two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water at the volume ratio of 6.5:3.5:5.0:5.0. Similarly, 3, 4 and 5 were prepared from the medium-polarity fraction using the system at the volume ratio of 4.0:5.0:5.0:6.0, and 6 and 7 were prepared from the higher-polarity fraction using the system at volume ratio of 3.0:5.0:4.0:6.7. A total of 6.2 mg of 1, 5.1 mg of 2, 3.9 mg of 3, 1.2 mg of 4, 5.7 mg of 5, 3.5 mg of 6, and 6.1 mg of 7 with purities of 88%, 82%, 91%, 80%, 92%, 81% and 83%, respectively, were yielded from total 62 mg fraction samples in three independent HSCCC runs. The structures of the purified ustilaginoidins were characterized by means of physicochemical and spectrometric analysis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins8010020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4728542PMC
January 2016

Main Ustilaginoidins and Their Distribution in Rice False Smut Balls.

Toxins (Basel) 2015 Oct 9;7(10):4023-34. Epub 2015 Oct 9.

College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.

Rice false smut has become an increasingly serious fungal disease in rice (Oryza sativa L.) production worldwide. Ustilaginoidins are bis-naphtho-γ-pyrone mycotoxins previously isolated from the rice false smut balls (FSBs) infected by the pathogen Villosiclava virens in rice spikelets on panicles. To investigate the main ustilaginoidins and their distribution in rice FSBs, five main bis-naphtho-γ-pyrones, namely ustilaginoidins A (1), G (2), B (3), I (4) and C (5), were isolated and identified by NMR and high-resolution mass spectrometry as well as by comparison with the data in the literature. The rice FSBs at early, middle and late maturity stages were divided into their different parts and the contents of five main ustilaginoidins for each part were determined by HPLC analysis. The results revealed that the highest levels of ustilaginoidins were in late stage rice FSBs, followed by those at middle stage. Most ustilaginoidins, 96.4% of the total quantity, were distributed in the middle layer at early stage. However, ustilaginoidins were mainly distributed in the outer and middle layers at middle and late stages. Small amounts of ustilaginoidins A (1) and G (2) were found in the inner part of rice FSBs at each maturity stage. The contents of ustilaginoidins A (1) and G (2) without hydroxymethyl groups at C-2 and C-2' of the γ-pyrone rings in rice FSBs were relatively high at early stage, while the contents of ustilaginoidins B (3), I (4), and C (5) with hydroxymethyl groups at C-2 or C-2' were relatively high at late stage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/toxins7104023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4626718PMC
October 2015

Bioactive bis-naphtho-γ-pyrones from rice false Smut pathogen Ustilaginoidea virens.

J Agric Food Chem 2015 Apr 25;63(13):3501-8. Epub 2015 Mar 25.

†MOA Key Laboratory of Plant Pathology, Department of Plant Pathology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.

Ustilaginoidins were bis-naphtho-γ-pyrones mycotoxins possessing an aR configuration of the chiral axis previously reported from the false smut balls of rice infected by the fungal pathogen Ustilaginoidea virens. To investigate the chemical diversity of these metabolites and their bioactivities, we fermented this fungus on solid rice media, which afforded the isolation of 13 ustilaginoidins, including seven new compounds, namely ustilaginoidins K-P, 1-6, and E1, 7, together with the known ustilaginoidins A, 8, D, 9, E, 10, F, 11, and G, 12, and isochaetochromin B2, 13. The structures of the new compounds were elucidated by using (1D, 2D) NMR, high-resolution mass spectrometry, UV, and circular dichroism, as well as by comparison with the literature data. A plausible biosynthesis pathway was proposed for these dimeric polyketides. The isolated compounds were evaluated for their antibacterial, cytotoxic, and radicle elongation inhibitory activities. Ustilaginoidins K, 1 and L, 2 showed cytotoxic activities on the A2780 human ovarian cancer cell line with IC50 values of 4.18 and 7.26 μM, respectively. Ustilaginoidins N, 4, D, 9, E, 10, and G, 12 were active against the tested pathogenic bacteria with MIC values in the range of 16-64 μg/mL. Ustilaginoidins O, 5, E, 10, and F, 11, and isochaetochromin B2, 13 displayed moderate inhibitory activity on the radicle elongation of rice seeds.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jafc.5b00694DOI Listing
April 2015

Enhanced production of botrallin and TMC-264 with in situ macroporous resin adsorption in mycelial liquid culture of the endophytic fungus Hyalodendriella sp. Ponipodef12.

Molecules 2014 Sep 10;19(9):14221-34. Epub 2014 Sep 10.

MOA Key Laboratory of Plant Pathology, Department of Plant Pathology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.

Hyalodendriella sp. Ponipodef12, an endophytic fungus from the hybrid "Neva" of Populus deltoides × P. nigra, is a high producer of the bioactive dibenzo-α-pyrones botrallin and TMC-264. However, both the botrallin and TMC-264 produced by Hyalodendriella sp. Ponipodef12 were retained as both intracellular and extracellular products. The aim of this study was to evaluate an in situ macroporous resin adsorption for enhancement of botrallin and TMC-264 production in mycelial liquid culture of Hyalodendriella sp. Ponipodef12. Production of botrallin and TMC-264 was most effectively enhanced by macroporous resin DM-301 among the thirteen nonionic macroporous resins tested. The highest botrallin yield (51.47 mg/L, which was 2.29-fold higher than the control at 22.49 mg/L) was obtained by adding resin DM-301 at 4.38% (g/mL) to the culture broth on day 24 and allowing a period of 4 days for adsorption. The highest TMC-264 yield reached 47.74 mg/L, which was 11.76-fold higher than that of the control (4.06 mg/L), and was achieved by adding DM-301 resin at 4.38% (w/v) in the culture broth on day 24 and allowing a period of 6 days for adsorption. The results show that in situ resin adsorption is an effective strategy for enhancing production of botrallin and TMC-264, and also for facilitating their recovery from mycelial liquid culture of Hyalodendriella sp. Ponipodef12.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules190914221DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6271592PMC
September 2014

Bis-naphtho-γ-pyrones from fungi and their bioactivities.

Molecules 2014 May 30;19(6):7169-88. Epub 2014 May 30.

MOA Key Laboratory of Plant Pathology, Department of Plant Pathology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.

Bis-naphtho-γ-pyrones are an important group of aromatic polyketides derived from fungi. They have a variety of biological activities including cytotoxic, antitumor, antimicrobial, tyrosine kinase and HIV-1 integrase inhibition properties, demonstrating their potential applications in medicine and agriculture. At least 59 bis-naphtho-γ-pyrones from fungi have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, biosynthesis, and structure, as well as their biological activities. Some considerations regarding to synthesis, production, and medicinal and agricultural applications of bis-naphtho-γ-pyrones are also discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules19067169DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6270783PMC
May 2014

Antimicrobial and antioxidant activities and effect of 1-hexadecene addition on palmarumycin C2 and C3 yields in liquid culture of endophytic fungus Berkleasmium sp. Dzf12.

Molecules 2013 Dec 13;18(12):15587-99. Epub 2013 Dec 13.

MOA Key Laboratory of Plant Pathology, Department of Plant Pathology, College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China.

Two spirobisnaphthalenes, namely palmarumycins C2 and C3, were isolated from cultures of the endophytic fungus Berkleasmium sp. Dzf12 after treatment with 1-hexadecene. After addition of 1-hexadecene at 10% to the medium on day 6 of culture, the maximal yields of palmarumycins C2 and C3 were obtained as 0.40 g/L and 1.19 g/L, which were 40.00 fold and 59.50 fold higher, respectively, in comparison with those of the control (0.01 g/L and 0.02 g/L). The results indicated that addition of 1-hexadecene can be an effective strategy for enhancing the production of palmarumycins C2 and C3 in liquid culture of endophytic fungus Berkleasmium sp. Dzf12. Palmarumycin C3 exhibited stronger antimicrobial and antioxidant activities than palmarumycin C2.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/molecules181215587DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6270283PMC
December 2013

Thermogravimetric investigation on the degradation properties and combustion performance of bio-oils.

Bioresour Technol 2014 19;152:267-74. Epub 2013 Nov 19.

Department of Forest Biomaterials, North Carolina State University, Raleigh, NC 27695, USA. Electronic address:

The degradation properties and combustion performance of raw bio-oil, aged bio-oil, and bio-oil from torrefied wood were investigated through thermogravimetric analysis. A three-stage process was observed for the degradation of bio-oils, including devolatilization of the aqueous fraction and light compounds, transition of the heavy faction to solid, and combustion of carbonaceous residues. Pyrolysis kinetics parameters were calculated via the reaction order model and 3D-diffusion model, and combustion indexes were used to qualitatively evaluate the thermal profiles of tested bio-oils for comparison with commercial oils such as fuel oils. It was found that aged bio-oil was more thermally instable and produced more combustion-detrimental carbonaceous solid. Raw bio-oil and bio-oil from torrefied wood had comparable combustion performance to fuel oils. It was considered that bio-oil has a potential to be mixed with or totally replace the fuel oils in boilers.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biortech.2013.11.028DOI Listing
August 2014
-->