Chemical Diversity of Bastard Balm (Melittis melisophyllum L.) as Affected by Plant Development

The phytochemical diversity of Melittis melissophyllum was investigated in terms of seasonal changes and age of plants including plant organs diversity. The content of phenolics, namely: coumarin; 3,4-dihydroxycoumarin; o-coumaric acid 2-O-glucoside; verbascoside; apiin; luteolin-7-O-glucoside; and o-coumaric; p-coumaric; chlorogenic; caffeic; ferulic; cichoric acids, was determined using HPLC-DAD. Among these, luteolin-7-O-glucoside, verbascoside, chlorogenic acid, and coumarin were the dominants. The highest content of flavonoids and phenolic acids was observed in 2-year-old plants, while coumarin in 4-year-old plants (272.06 mg 100 g-1 DW). When considering seasonal changes, the highest content of luteolin-7-O-glucoside was observed at the full flowering, whereas verbascoside and chlorogenic acid were observed at the seed-setting stage. Among plant organs, the content of coumarin and phenolic acids was the highest in leaves, whereas verbascoside and luteolin-7-O-glucoside were observed in flowers. The composition of essential oil was determined using GC-MS/GC-FID. In the essential oil from leaves, the dominant was 1-octen-3-ol, whilst from flowers, the dominant was α-pinene.

Efficient removal of GenX (HFPO-DA) and other perfluorinated ether acids from drinking and recycled waters using anion exchange resins

Carcinogenic GenX chemicals, heptafluoropropylene-oxide-dimer-acid (HFPO-DA), have been recently detected in surface, ground and recycled water sources worldwide. However, GenX removals under the influence of variable characteristics of the organic and inorganic compounds present in the natural water sources, have often been overlooked in scientific literature. This is critically important given that the ionic composition and characteristics of organic matter in natural waters are spatially and seasonally variable. A strongly basic anion exchange (IX) resin was used to remove GenX and two other perfluorinated ether acids (PFEAS) from natural surface and recycled water sources. Factors influencing the uptake behavior included the PFEAS concentrations, resin dosage, and background anion characteristics. The equivalent background compound was employed to evaluate the competitive uptake between natural organic matter (NOM), inorganic ions and PFEAS in natural water matrices. Experimental data were compared with different mathematical and physical models and it was depicted that approximately 4-6% of the initial NOM competed with PFEAS for active exchange sites. Further, IX was able to achieve complete PFEAS removal (C_final<10 ng/L) with simultaneous removal of>60% NOM and >80% inorganic ions. Results of this study indicate that IX exhibits great potential for PFEAS removal from natural drinking water sources.

Polypropionate Derivatives with Mycobacterium tuberculosis Protein Tyrosine Phosphatase B Inhibitory Activities from the Deep-Sea-Derived Fungus Aspergillus fischeri FS452

Fiscpropionates A-F (1-6), six new polypropionate derivatives featuring an unusual long hydrophobic chain, were isolated from the deep-sea-derived fungus Aspergillus fischeri FS452. Their structures were elucidated on the basis of spectroscopic analysis, and the absolute configurations were determined by J-HMBC analysis, electronic circular dichroism (ECD) calculations, and the modified Mosher's method. This is the first discovery of polypropionates from marine-derived fungi, and compounds 4 and 5 represent the first examples of polypropionate derivatives containing a 3-hydroxypiperidin-2-one as part of an imide linkage. In addition, compounds 1-4 exhibited significant inhibitory activities against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB) with the IC₅₀ values of 5.1, 12, 4.0, and 11 μM, respectively. Enzyme kinetic experiments suggested that they all acted through a noncompetitive mechanism. A preliminary structure-activity relationship is discussed.

Extraction and Determination of Trace Amounts of p-Coumaric Acid in Vinegar, Carrot Juice, and Seed Extract from Silybum marianum (L.) Gaertn

In this study, for the monitoring and quantification of p-coumaric acid (p-CA) in vinegar, carrot juice, and seed extract from the plant species Silybum marianum (L.) Gaertn, an efficient and low-cost analytical method has been applied. For this purpose, a dispersive liquid-liquid microextraction (DLLME) method, followed by UV-Vis spectrophotometric detection, was used. To form a cloudy solution, a binary mixture containing ethanol as a disperser solvent and chloroform as an extraction solvent was rapidly injected by syringe into a sample solution containing p-CA. After centrifugation, dilution of the obtained organic phase was done with the proper amount of ethanol, and the phase was transferred into a micro cell for subsequent measurement. Some effective parameters for the DLLME method, such as the volume of disperser solvent and extraction solvent, pH, and salt concentration were inspected by a 24 full factorial central composite design using design Export Software. Under the optimized conditions, linearity was between 10 and 150 ng/mL, and the LOD was 2.3 ng/mL. The results of the proposed method were similar to the obtained results using a GC with flame-ionization detection method.

[The volatile fatty acids in children with dysfunction of biliary tract]

The volatile fatty acids are metabolites of bacteria reflecting condition and disbiotic alterations of microflora of gastrointestinal tract. The study was carried out to determine qualitatively volatile fatty acids in saliva of children with dysfunction of biliary tract and healthy ones. The indices of volatile fatty acids were analyzed in 46 children aged 7-17 years and with dysfunction of biliary tract. The comparison group included 34 healthy children aged from 7 to 17 years. The gas-liquid chromatography was applied to qualitatively detect acetic, butyric, isovaleric acids (volatile fatty acids). The automatedgas chromatograph "Crystal deluxe 4000" with capillary column "HP-FFAP" and flame ionizing detector was used. The study established decreasing of anaerobic index, increasing of acetic, propionic acids and sum of volatile fatty acids in saliva of children of main group as opposed to children of comparison group. The possible role of bacterial metabolites and bacteria in pathogenesis of dysfunction of biliary tract in children. The description is made of one of possible mechanisms of increasing of volatile fatty acids in saliva under dysfunction of biliary tract. The integral indices of volatile fatty acids of saliva are the new additional criteria for diagnostic of dysfunction of biliary tract in children.

Antitrypanosomal Activity of a Novel Taccalonolide from the Tubers of Tacca leontopetaloides

INTRODUCTION

Several taccalonolides with various bioactivities have been isolated from Tacca species but no studies to isolate taccalonolides with anti-trypanosomal activity from Tacca leontopetaloides have been reported.

OBJECTIVES

To analyse extracts of the roots of Tacca leontopetaloides, purify the extracts by column chromatography and identify isolated compounds by spectroscopic methods. The compounds and fractions will be tested for antitrypanosomal activity in vitro against Trypanosoma brucei brucei.

MATERIAL AND METHODS

Dried roots or tubers of Tacca leontopetaloides, chromatographic separation and spectroscopic identification.

RESULTS

A novel taccalonolide A propanoate and some known taccalonolides were isolated and their structures were determined by NMR and mass spectrometry

CONCLUSION

Several taccalonolides were isolated from Tacca leontopetaloides and were found to have in vitro antitrypanosomal activity against Trypanosoma brucei brucei and EC50 values for the isolated compounds were from 0.79 µg/mL. Copyright © 2016 John Wiley & Sons, Ltd.

Two new secondary metabolites from the marine-derived fungus Nigrospora sphaerica

Two new secondary metabolites, (2S)-5-acetamidopentyl-2-hydroxypropanoate (1) and 2, 5, 7-trihydroxy-4-(3'-methylbut-2'-en-1'-yl) oxy-2H-naphtho [1, 8-b c] furan-9-one (2) were isolated from the marine-derived fungus Nigrospora sphaerica. The structures were established on the basis of their spectroscopic data, including 1D NMR and 2D NMR, HR-TOF-MS, and the absolute configuration of compound 1 was determined by the Mosher method.

Gulypyrones A and B and Phomentrioloxins B and C Produced by Diaporthe gulyae, a Potential Mycoherbicide for Saffron Thistle (Carthamus lanatus)

A virulent strain of Diaporthe gulyae, isolated from stem cankers of sunflower and known to be pathogenic to saffron thistle, has been shown to produce both known and previously undescribed metabolites when grown in either static liquid culture or a bioreactor. Together with phomentrioloxin, a phytotoxic geranylcyclohexenetriol recently isolated from a strain of Phomopsis sp., two new phytotoxic trisubstituted α-pyrones, named gulypyrones A and B (1 and 2), and two new 1,O- and 2,O-dehydro derivatives of phomentrioloxin, named phomentrioloxins B and C (3 and 4), were isolated from the liquid culture filtrates of D. gulyae. These four metabolites were characterized as 6-[(2S)2-hydroxy-1-methylpropyl]-4-methoxy-5-methylpyran-2-one (1), 6-[(1E)-3-hydroxy-1-methylpropenyl]-4-methoxy-3-methylpyran-2-one (2), 4,6-dihydroxy-5-methoxy-2-(7-methyl-3-methyleneoct-6-en-1-ynyl)cyclohex-2-enone (3), and 2,5-dihydroxy-6-methoxy-3-(7-methyl-3-methyleneoct-6-en-1-ynyl)cyclohex-3-enone (4) using spectroscopic and chemical methods. The absolute configuration of the hydroxylated secondary carbon of the 2-hydroxy-1-methylpropyl side chain at C-6 of gulypyrone A was determined as S by applying a modified Mosher's method. Other well-known metabolites were also isolated including 3-nitropropionic, succinic, and p-hydroxy- and p-methylbenzoic acids, p-hydroxybenzaldehyde, and nectriapyrone. When assayed using a 5 mM concentration on punctured leaf disks of weedy and crop plants, apart from 3-nitropropionic acid (the main metabolite responsible for the strong phytotoxicity of the culture filtrate), phomentrioloxin B caused small, but clear, necrotic spots on a number of plant species, whereas gulypyrone A caused leaf necrosis on Helianthus annuus plantlets. All other compounds were weakly active or inactive.

Deconins A-E: Cuparenic and Mevalonic or Propionic Acid Conjugates from the Basidiomycete Deconica sp. 471

Bioassay-guided fractionation of antibacterial extracts from cultures of a basidiomycete from Northern Thailand, which represents a new species of the genus Deconica, yielded the terpenoid deconin A (1), whose structure was elucidated by spectral methods (NMR, HRMS) as a cuparenic/mevalonic acid conjugate. The absolute configuration of 1 was determined after saponification and comparison of specific rotations of the resulting cuparenic acid and mevalonolactone with authentic standards and literature data. Six minor congeners (2-7) were isolated and identified, and their antimicrobial and cytotoxic effects are reported. Compounds 1-4 are the first natural products featuring an unmodified mevalonic acid residue as a building block.

Structure of a putative fluorinated natural product from Streptomyces sp. TC1

Fluorine-containing natural products are extremely rare. The recent report on the isolation and biological activity of the bacterial secondary metabolite 3-(3,5-di-tert-butyl-4-fluorophenyl)propionic acid was thus highly remarkable. The compound contained the first aromatic fluorine substituent known to date in any natural product. The promise to discover an enzyme capable of aromatic fluorination in the producing strain Streptomyces sp. TC1 prompted our immediate interest. A close inspection of the originally reported analytical data of the fluoro metabolite revealed inconsistencies that triggered us to validate the reported structure. The results of these efforts are presented in this communication.

Fate and long-term inhibitory impact of ZnO nanoparticles during high-rate anaerobic wastewater treatment

The aim of this study was to evaluate the long-term effect of ZnO nanoparticles (NPs) on the performance of high-rate anaerobic bioreactors. Laboratory-scale upflow anaerobic sludge blanket (UASB) reactors were fed with a mixture of volatile fatty acids and exposed to either low (0.32 mg Zn L(-1)) or high (34.5 mg Zn L(-1)) concentrations of ZnO NPs. Exposure to high NP concentrations caused a rapid and permanent decline in the methane production and the removal of acetate and propionate. In contrast, a gradual and partial inhibitory response was observed in the reactor exposed to low NP concentrations. The long-term effect of the NP exposure was also evident from a decline in the specific methanogenic activity, which was more severe for the acetoclastic compared to the hydrogenotrophic methanogens. ZnO NPs were removed by 62-82% during passage through the UASB reactors. The results taken as a whole indicate that ZnO NPs cause severe inhibition of acetoclastic methanogens. Even sub-ppm levels of the nano-ZnO in the influent had a negative impact on the performance of the UASB reactor due to long-term exposure of methanogens to NPs that accumulated in the sludge bed.

Isolation, characterization, and in vitro cytotoxicity of new sesquiterpenoids from Achillea clavennae

Further phytochemical investigation of the aerial parts of Achillea clavennae has resulted in the isolation of three new sesquiterpene lactones: two highly oxygenated germacranolides (1, 2) and the iso-seco-guaianolide 9(R)-acetoxy-3-O-methyl-iso-seco-tanapartholide (3). Eight known compounds were also found, of which 9α-acetoxycanin (5), sintenin (6), and oleanolic acid (7) were detected for the first time. The structures of the isolated compounds were elucidated by combined spectroscopic methods (1D and 2D NMR, HRESIMS, CIMS, and FTIR). While the predominant metabolite germacranolide sintenin (6) was not cytotoxic, the new iso-seco-guaianolide (3) displayed cytotoxicity comparable to that of cisplatin and the lactone apressin (4), inducing partly apoptotic death in human U251 and rat C6 glioma cell lines.

Two new compounds from the fungus Penicilliumcrustosum YN-HT-15

Our current natural product program researches the second metabolites of a fungus Penicilliumcrustosum YN-HT-15 isolated from the red soil (Yunnan Province, China), to discover potential antitumor chemical entities. Two new compounds were isolated from the ethyl acetate extract of the fermentation broth of the fungus, and their structures were characterized as 1-(2',4'-dihydroxy-5'-methyl-3'-methylsulfanylmethyl-phenyl)-ethanone and R-3-(3'-acetyl-2',6'-dihydroxy-5'-methylphenyl)-2-methyl-propionic acid methyl ester on the basis of spectroscopic data.

Extending the record of bis-γ-pyrone polypropionates from marine pulmonate mollusks

The isolation and structure elucidation of 10 unreported polypropionate metabolites (compounds 6-15), structurally related to either ilikonapyrone (1) or onchidione (3), from two onchidiid pulmonate mollusk species are discussed. Structure elucidation was achieved by NMR spectroscopy and chemical correlation with model compounds. Evaluation of in vitro growth-inhibitory properties in human cancer cells was also carried out on some of the isolated polypropionates including previously reported onchidione metabolites.

Nodulisporisteriods A and B, the first 3,4-seco-4-methyl-progesteroids from Nodulisporium sp

Two new 4-methyl-progesteroids, nodulisporisteriod A (1) and nodulisporisteriod B (2), were isolated from the extract of an endolichenic fungal strain Nodulisporium sp. (No. 65-17-2-1), along with two related metabolites, demethoxyviridin (3) and inoterpene B (4). Their structures were determined by detailed spectroscopic analyses, X-ray crystallographic analysis and comparison of the NMR data with those of the closely related compounds previously reported. Nodulisporisteriod A (1) and nodulisporisteriod B (2) possess new carbon skeletons, which are the first cases of fission at C-3,4 in 4-methyl-progesteroids. A hypothetical biosynthetic pathway for 1 and 2 was proposed. Moreover, the Aβ42 aggregation inhibitory activities of 1-4 were evaluated using standard thioflavin T (ThT) fluorescence assay with epigallocatechin gallate (EGCG) as positive control. Demethoxyviridin (3) displayed anti-Aβ42 aggregation activity with IC50 value of 13.4μM.

Biosynthesis of poly(3-hydroxypropionate) from glycerol by recombinant Escherichia coli

Poly(3-hydroxypropionate) (P3HP) is a biodegradable and biocompatible thermoplastic. In this study, a P3HP biosynthetic pathway from glycerol was constructed in recombinant Escherichia coli. The genes for glycerol dehydratase and its reactivating factor (dhaB123 and gdrAB, from Klebsiella pneumoniae), propionaldehyde dehydrogenase (pduP, from Salmonella typhimurium), and polyhydroxyalkanoate synthase (phaC1, from Cupriavidus necator) were cloned and expressed in E. coli. After culture condition optimization, the final engineered strain accumulated 10.1 g/L P3HP (46.4% of the cell dry weight) using glycerol and glucose as cosubstrates in an aerobic fed-batch fermentation. To date, this is the highest P3HP production without addition of any expensive precursor.

Two new compounds from the metabolites of a marine-derived actinomycete Streptomyces cavourensis YY01-17

Our current marine natural product program investigated the second metabolites of an actinomycete Streptomyces cavourensis YY01-17 originating from the Antarctic ecological niche to discover potential antitumor chemical entities. Two new compounds, along with a known compound, were isolated from the ethyl acetate extract of the fermentation broth of the marine-derived actinomycete, and their structures were elucidated, respectively, as 2(S)-3'-hydroxybutan-2'-yl 2-hydroxypropanoate (1), (E)-3-hydroxy-2,4-dimethylhept-4-enamide (2), and 2-hydroxy-3-methylbutanoic acid (3) on the basis of spectroscopic data interpretation.

[Isolation of quizalofop-p-ethyl-degrading bacteria from soil by DGGE-colony in situ hybridization]

Naturally occurring bacteria isolates capable of metabolizing pesticides have received considerable attention because they offer the possibility of both environmentally friendly and in situ remediation. The effect of herbicide quizalofop-p-ethyl on bacterial community in soil was analyzed using the technique of PCR-DGGE for isolating strains biodegrading quizalofop-p-ethyl. Results indicated that the soil bacterial community structures significantly changed after adding quizalofop-p-ethyl. The bacterial diversity of soil showed an increasing-decreasing-increasing trend. The largest changes occurred in the 9th day and then became stabilized. According to the sequencing results of bands in DGGE profiles, it inferred that members of bacterial genera Pseudomonas, Massilia and Burkholderia had tolerance to quizalofop-p-ethyl, and the potential for degradation. These microbial groups could be used to isolate and screen as the indigenous microbial resources to reduce pesticide residues. Digoxigenin-labeled probes had been synthesized based on the sequencing results of bands in the DGGE profiles, and three bacterial strains capable of biodegrading quizalofop-p-ethyl were isolated from soil by colony in situ hybridization technique. The strain named L1 was able to utilize quizalofop-p-ethyl as the sole source of carbon. The strain was identified as Pseudomonas sp., based on the phylogenetic analysis of 16S rRNA. The degrading ability of strain L1 in minimal medium with quizalofop-p-ethyl was investigated by HPLC. The quizalofop-p-ethyl content decreased by almost 50% after 7 days, and the biomass of strain L1 increased while the content of quizalofop-p-ethyl was decreased. This confirmed that the strain L1 had the capacity of degradation. This result provided a basis for future research on degradation mechanism and functional genes.

Mitigating ammonia inhibition of thermophilic anaerobic treatment of digested piggery wastewater: use of pH reduction, zeolite, biomass and humic acid

High free ammonia released during anaerobic digestion of livestock wastes is widely known to inhibit methanogenic microorganisms and result in low methane production. This was encountered during our earlier thermophilic semi-continuously fed continuously-stirred tank reactor (CSTR) treatment of piggery wastewater. This study explored chemical and biological means to mitigate ammonia inhibition on thermophilic anaerobic treatment of piggery wastewater with the aim to increase organic volatile carbon reduction and methane production. A series of thermophilic anaerobic batch experiments were conducted on the digested piggery effluent to investigate the effects of pH reduction (pH 8.3 to 7.5, 7.0 and 6.5) and additions of biomass (10% v/v and 19% v/v anaerobic digested piggery biomass and aerobic-anaerobic digested municipal biomass), natural zeolite (10, 15 and 20 g/L) and humic acid (1, 5 and 10 g/L) on methane production at 55 °C for 9-11 days. Reduction of the wastewater pH from its initial pH of 8.3 to 6.5 produced the greatest stimulation of methane production (3.4 fold) coupled with reductions in free ammonia (38 fold) and total volatile fatty acids (58% TVFA), particularly acetate and propionate. Addition of 10-20 g/L zeolite to piggery wastewater with and without pH reduction to 6.5 further enhanced total VFA reduction and methane production over their respective controls, with 20 g/L zeolite producing the highest enhancement effect despite the ammonia-nitrogen concentrations of the treated wastewaters remaining high. Without pH reduction, zeolite concentration up to 20 g/L was required to achieve comparable methane enhancement as the pH-reduced wastewater at pH 6.5. Although biomass (10% v/v piggery and municipal wastes) and low humic acid (1 and 5 g/L) additions enhanced total VFA reduction and methane production, they elevated the residual effluent total COD concentrations over the control wastewaters (pH-unadjusted and pH-reduced) unlike zeolite treatment. The outcomes from these batch experiments support the use of pH reduction to 6.5 and zeolite treatment (10-20 g/L) as effective strategies to mitigate ammonia inhibition of the thermophilic anaerobic treatment of piggery wastewater.

Efficient utilization of hemicellulose hydrolysate for propionic acid production using Propionibacterium acidipropionici

Hemicellulose, which contains glucose, xylose, and arabinose as the 3 main sugars, is an important renewable source for biorefinery. In this study, propionic acid production from glucose, xylose, or arabinose using Propionibacterium acidipropionici ATCC 4875 was investigated. Using xylose, the predominant sugar in hemicellulose, a final propionic acid concentration of 53.2 g l(-1) was obtained via fed-batch fermentation. Using corncob molasses, a waste by-product from xylitol production as a representative of hemicellulose hydrolysate, the final concentration of propionic acid was 71.8 g l(-1), with a corresponding productivity of 0.28 g l(-1) h(-1). The present study suggests that hemicellulose hydrolysate is an excellent carbon source for efficient propionic acid production by this strain.

Inhibition of prostate cancer (LNCaP) cell proliferation by volatile components from Nagami kumquats

Fresh Nagami kumquats (Fortunella margarita) were subjected to hydrodistillation using a Clevenger-type apparatus to obtain volatile oil. The chemical composition of the volatile oil was analyzed by GC-MS using Rtx-5 Sil MS and DB Wax columns. A total of 25 volatile compounds were identified by mass spectra, retention index, and comparison with known standards. The major identified compounds are d-limonene (41.64 %), β-myrecene (16.54 %), linalyl propionate (9.55 %), and germacrene-D (5.93 %) from the Rtx-5 Sil MS column; d-limonene and β-myrecene were also separated as major compounds on the DB wax column. The oil is rich in hydrocarbons (77.41 %) consisting of 60.05 % monoterpenes and 17.36 % sesquiterpenes. Interestingly, oxygenated hydrocarbons (17.6 %) were also found in kumquat volatile oil. Certain volatile compounds were also confirmed by positive chemical ionization and NMR spectra. Further, the volatile oil demonstrated good DPPH radical scavenging activity and antioxidant capacity. Kumquat volatile oil at 200 ppm concentration exhibited 55 %, 61 %, and 63.4 % inhibition of human prostate cancer (LNCaP) cell proliferation at 24, 48, and 72 h, respectively, by cell count assays. Significant increases in expression of bax/bcl2 and p53 proteins confirmed that volatile oil induces apoptosis. In addition, inhibition of inflammatory markers such as NF-κB and Cox-2 was observed. The cleavage of caspase-8 in the LNCaP cells treated with volatile oil demonstrated that apoptosis occurred through an extrinsic pathway. This is the first report of the identification and possible mechanisms of in vitro antiproliferative effects of kumquat volatile components on human prostate cancer (LNCaP) cells.

Polypropionates from the South African marine mollusk Siphonaria oculus

Three new polypropionate metabolites, 6Z,8E-Δ(8)-siphonarienfuranone (1), 6E,8E-Δ(8)-siphonarienfuranone (2), and 6E,8E-3-hydroxy-4,6,8,10,12-pentamethylpentadeca-6,8-dien-5-one (3), and the known polypropionate siphonarienfuranone (4) were isolated from the intertidal South African marine mollusk Siphonaria oculus. Evidence is presented to suggest that 1, 2, and 4 may cyclize from an acylic precursor on chromatographic workup of the acetone extract of this mollusk.

Novel in situ product removal technique for simultaneous production of propionic acid and vitamin B12 by expanded bed adsorption bioreactor

A new type of in situ product removal (ISPR) technique of expanded bed adsorption (EBA) bioreactor was studied to simultaneously produce extracellular propionic acid and intracellular vitamin B12 by Propionibacterium freudenreichii CICC 10019. Resin screening experiments showed that the ZGA330 resin have the best biocompatibility and highest adsorption for propionic acid. Through the EBA bioreactor, propionic acid could be recovered efficiently by semi-continuous recirculation of the unfiltered broth, which eliminated the feedback inhibition of propionic acid. Fed-batch fermentation was carried out using the EBA system, resulting in a propionic acid concentration of 52.5 g L(-1) and vitamin B12 concentration of 43.04 mg L(-1) at 160 h, which correspond to product yields of 0.66 g g(-1) and 0.54 mg g(-1), respectively. The present study suggests that the EBA bioreactor can be utilized for the simple and economical production of propionic acid and vitamin B12 in a single fermentation process.

Unusual compounds from exudates of Dionysia diapensifolia and D. gaubae var. megalantha (Primulaceae)

Exudates of Dionysia diapensifolia yielded (R)-(+)-3-acetoxy-3-phenyl-propiophenone as a new natural product with a basic dihydrochalcone structure, which was elucidated unequivocally by mass spectrometry and NMR spectroscopy. The sesquiterpenoidcarissone was found as the major compound in the exudate of D. gaubae var. megalantha. Sesquiterpenoids have so far not been described as exudate constituents of Primula and Dionysia. Structural identifications are discussed in detail, and the significance of the occurrence of these unusual compounds in exudates of Primulaceae is shortly addressed.

A new monacolin analogue from Xuezhikang capsule

Xuezhikang capsule (ethanol extract of red yeast rice) which produced by Beijing WBL Peking University Biotech Co., Ltd., is a traditional Chinese medication with 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibiting activity. Clinical trials indicated that Xuezhikang with lipid-lowering action could reduce the risk of cardiac events and total mortality of Chinese coronary heart disease patients. To exactly explain the clinical features of Xuezhikang, we undertook a complete study of the chemical constituents of Xuezhikang. This study resulted in the isolation of a new monacolin analogue, named alpha, beta-dehydromonacolin L (1), along with two known compounds: monacolin L (2) and 3-(2, 6-dimethyl-1, 2, 4a, 5, 6, 7, 8, 8a-octahydronaphthalen-1-yl)propanoic acid (3). The chemical structures were determined by extensive 1D and 2D NMR and MS spectroscopic analysis.

Two new phenylpropanoids and one propanoate from Morinda citrifolia

Two new phenylpropanoids, methyl 3-(2,4-dihydroxy-5-methoxyphenyl)propionate (1) and butyl 3-(2,4-dihydroxy-5-methoxyphenyl)propionate (2), and one unusual propanoate, 5-hydroxyhexyl 2-hydroxypropanoate (3), were isolated from the fruits of Morinda citrifolia. Their structures were established using MS and NMR methods.

Differential enantioselectivity of quizalofop ethyl and its acidic metabolite: direct enantiomeric separation and assessment of multiple toxicological endpoints

Transformation products usually differ in environmental and toxicological properties compared to the parent contaminants, thus causing potential and unknown environmental risks. To elucidate differential chiral recognition of the aryloxypropanoate herbicide quizalofop ethyl (QE) and its primary product (quizalofop acid, QA), their enantiomeric separation and toxicological impacts to two freshwater algae were investigated. Addition of trace water (0.02-0.08%, v/v) to the mobile phase selectively affected retention of analyte and induced simultaneous enantio-separation for the two compounds with intrinsical water-specific resolution mechanisms, although they both possessed a chiral center in the 2-position of propionates. In algal suspensions, QE was rapidly degraded to produce the acid metabolite (QA), and the product further declined, whereas a reduction of QA as starting compound did not occur. Uptake and/or transformation of QE and QA were found a lack of enantioselectivity and isomer inversion, while cellular membrane permeability, membrane potential and algal growth showed enantioselectivity to different extents. These results suggested the presence of receptor chirality that was involved in the toxicological processes but invalid for uptake and transformation. Therefore, quizalofop acid, identified as environmentally relevant contaminant associated with application of the herbicide, participated in the toxicological processes of the parent compound, and exhibited distinct toxicological and chromatographic retention properties.

Demixing of severely overlapped ¹H NMR resonances and interpretation of anomalous intensity pattern of dipolar coupled A₃ spins in a weakly aligning medium

We report a single (13)C spin edited selective proton-proton correlation experiment to decipher overcrowded (13)C coupled proton NMR spectra of weakly dipolar coupled spin systems. The experiment unravels the masked (13)C satellites in proton spectrum and permits the measurement of one bond carbon-proton residual dipolar couplings in I(3)S and for each diastereotopic proton in I(2)S groups. It also provides all the possible homonuclear proton-proton residual couplings which are otherwise difficult to extract from the broad and featureless one dimensional (1)H spectrum, in addition to enantiodifferentiation in a chiral molecule. Employment of heteronuclear ((13)C) decoupling in the evolution period results in complete demixing of overlapped signals from enantiomers. The observed anomalous intensity pattern in strongly dipolar coupled methyl protons in methyl selective correlation experiment has been interpreted using polarization operator formalism.

Optimization and scale-up of propionic acid production by propionic acid-tolerant Propionibacterium acidipropionici with glycerol as the carbon source

Propionic acid production by Propionibacterium acidipropionici with glycerol as sole carbon source was studied in 7-L batch and 10m(3) bioreactor cultures. In batch cultures, propionic acid production increased and specific cell growth rate decreased with increasing glycerol concentrations. Maximum propionic acid production and productivity reached 44.62+/-1.12g/L and 0.20+/-0.0075gL(-1)h(-1)at 220h, respectively, when glycerol was fed at a constant rate of 0.01L/h from 72 to 120h with an initial glycerol concentration of 30g/L. In the 10m(3) bioreactor, maximum propionic acid production reached 47.28+/-0.12g/L at 240h. This glycerol feeding approach may be useful for propionic acid production on an industrial scale.

Determination of the gamma-secretase inhibitor MK-0752 in human plasma by online extraction and electrospray tandem mass spectrometry (HTLC-ESI-MS/MS)

A sensitive and rapid HTLC-ESI-MS/MS method with an advanced online sample preparation was developed for determination of the gamma-secretase inhibitor MK-0752 in human plasma using an internal standard. Plasma samples (100 microL) were diluted and injected directly onto an online extraction column (Cohesive Cyclone MAX 0.5 mm x 50 mm, > 30 microm), the sample matrix was washed out with an aqueous solution, and retained analytes were eluted out and transferred directly to the analytical column (Phenomenex Gemini 3 micron C18 110A, 50 mm x 2.0 mm at 50 degrees C) for separation using a gradient mobile phase. The eluted analytes were then detected on an API-3000 LC-MS/MS System with ESI and a negative multiple reaction monitoring mode. The monitored ion transitions were m/z 441-->175 for MK-0752 and 496-->175 for the internal standard. Online extraction recoveries were 81%. The method was validated and was linear in the range of 0.05-50 microg/mL. Within-day and between-day precisions were<8.6%, and accuracies were 0.7 and 7.1%. This method was applied to the measurement of plasma MK-0752 levels in a Phase I study of pediatric patients with recurrent or refractory brain tumors.

The effect of pH on anaerobic fermentation of primary sludge at room temperature

The effect of pH in the range of 3.0-11.0 on anaerobic fermentation of primary sludge (PS) was investigated at room temperature. The experimental results showed that the concentrations of soluble chemical oxygen demands (SCOD), soluble protein and carbohydrate and short-chain fatty acids (SCFAs) under alkaline conditions were significantly higher than those under other pHs. At fermentation time of 5 days, the average SCFAs concentration increased from 968 to 3511mg COD/L with the increase of pH from 3.0 to 10.0. However, further increasing pH to 11.0 resulted in the decrease of SCFAs. At pH 10.0, acetic, propionic and iso-valeric acids were the three main products, and the volatile suspended solids (VSS) reduction reached 38%. It was also observed that at any pH value investigated, there were obvious ammonia and phosphorus releases during fermentation. According to this study it is obvious that alkaline pH benefited the soluble organic carbon production from PS.

Underivatized polyamine analysis in plant samples by ion pair LC coupled with electrospray tandem mass spectrometry

Polyamines are key regulators of cell development and many plant responses to environmental challenges, however, their functions still remain unclear in complex interactions with other hormones and in biotic or abiotic stress. This lack of knowledge derives from the difficulties on measuring natural polyamines in plants. Here, we present a fast multiresidue method for putrescine (Put), 1,3-diaminopropane (DAP), l-ornithine, spermidine (Spd) and spermine (Spn) measurements in plant samples. Polyamine determination is based on a perchloric acid extraction followed by a simple filtration procedure without previous derivatization. Polyamines are resolved by HPLC in a C18 common column and quantified by electrospray ionization tandem mass spectrometry. (13)C(4)-putrescine and 1,7-diaminoheptane standards were added prior to sample extraction to achieve an accurate quantification in a single run. Chromatography of polyamines presents poor retention when reverse phase C18 common columns are used, because they are very polar compounds and contain several positive charges. To circumvent this problem ionic pairing technique has been used successfully with heptafluorobutyric acid (HFBA) at 1mM in the aqueous phase and 25mM in the sample. Improvement of the signal depleted by HFBA has been achieved by adding 1% of propionic acid to the aqueous and organic eluents. All together, gives a method accurate enough to determine polyamines in plants. To demonstrate the usefulness of the method it has been validated in Arabidopsis thaliana samples and polyamines have been determined in several genotypes that over express (35S::ADC2 line 3.6) or are disrupted (adc2) in the Arginine Decarboxylase2 (ADC2) gene.

Study on solvent extraction of propionic acid from simulated discharged water in vitamin B12 production by anaerobic fermentation

The potential of recovering propionic acid from discharged water in vitamin B(12) production by anaerobic fermentation was investigated in this paper. A primary amine, N(1923), was used as the extractant, kerosene as diluter and n-octanol as modifier. The influences of the content of N(1923) in the organic phase, the phase ratio and the pH of aqueous phase on the extraction yield of propionic acid were studied. The organic phase composition with the volume ratio was proposed of N(1923):kerosene:n-octanol as 45:35:20. Under conditions of the phase ratio (o/w) as 1:4, the pH of aqueous phase of 3.0 and after 5 min extraction, the extraction yield of propionic acid can be over 97%.

Three new compounds from endophytic fungus L10 of Cephalotaxus hainanensis

Three new compounds, 4-hydroxyphenethyl-2'-hydroxypropanoate (1), 6-(1',2'-dimethyloxiran-1'-yl)-4-methoxy-3-methyl-2H-pyran-2-one (2), 6-(1-hydroxyethyl)-4-methoxy-3-methyl-2H-pyran-2-one (3), along with the two known compounds, nectriapyrone (4) and wermopyrone (5), have been isolated from the endophytic fungus of Cephalotaxus hainanensis. Their structures were determined on the basis of chemical and spectroscopic methods.

Isolation and identification of alpha-CEHC sulfate in rat urine and an improved method for the determination of conjugated alpha-CEHC

2,5,7,8-Tetramethyl-2-(2'-carboxyethyl)-6-hydroxychroman (alpha-CEHC), the water-soluble metabolite of alpha-tocopherol (alpha-TOH) with a shortened side chain but an intact hydroxychroman structure, has been identified in human urine and are thought to be produced in significant amount at excess intake of alpha-TOH. In previous studies, CEHCs in biological specimens were measured by HPLC, GC-MS or LC-MS, preceded by a hydrolysis procedure using either enzyme or methanolic HCl. In an attempt to analyze alpha-CEHC in rat urine accordingly, we observed that enzyme hydrolysis was relatively inefficient in releasing alpha-CEHC compared to high concentrations of HCl. The HCl releasable alpha-CEHC conjugate was isolated and chemically identified as 6-O-sulfated alpha-CEHC (alpha-CEHC sulfate). Using the synthetic alpha-CEHC sulfate standard, it was found that sulfatase could not hydrolyze to a significant extent. On the other hand, pretreatment with HCl at 60 degrees C in the presence of ascorbate, followed by a one-step ether extraction, not only hydrolyzed the sulfate conjugate completely but also extracted alpha-CEHC with high recovery. The inclusion of ascorbate minimized the conversion of alpha-CEHC to alpha-tocopheronolactone in the HCl pretreatment. A complete procedure for the quantitative analysis of alpha-CEHC including HCl hydrolysis, ether extraction and reverse phase isocratic HPLC-ECD was thus established. In conclusion, alpha-CEHC sulfate was isolated and identified as the HCl-releasable conjugate of alpha-CEHC in rat urine. A rapid and sensitive method with high reproducibility for the determination of free, conjugated and total alpha-CEHC is then established.

Detection, isolation and characterization of a root-exuded compound, methyl 3-(4-hydroxyphenyl) propionate, responsible for biological nitrification inhibition by sorghum (Sorghum bicolor)

Nitrification results in poor nitrogen (N) recovery and negative environmental impacts in most agricultural systems. Some plant species release secondary metabolites from their roots that inhibit nitrification, a phenomenon known as biological nitrification inhibition (BNI). Here, we attempt to characterize BNI in sorghum (Sorghum bicolor). In solution culture, the effect of N nutrition and plant age was studied on BNI activity from roots. A bioluminescence assay using recombinant Nitrosomonas europaea was employed to determine the inhibitory effect of root exudates. One major active constituent was isolated by activity-guided HPLC fractionations. The structure was analysed using NMR and mass spectrometry. Properties and the 70% inhibitory concentration (IC(70)) of this compound were determined by in vitro assay. Sorghum had significant BNI capacity, releasing 20 allylthiourea units (ATU) g(-1) root DW d(-1). Release of BNI compounds increased with growth stage and concentration of supply. NH4+ -grown plants released several-fold higher BNI compounds than NO3- -grown plants. The active constituent was identified as methyl 3-(4-hydroxyphenyl) propionate. BNI compound release from roots is a physiologically active process, stimulated by the presence of NH4+. Methyl 3-(4-hydroxyphenyl) propionate is the first compound purified from the root exudates of any species; this is an important step towards better understanding BNI in sorghum.

3-Methylthiopropionic acid ethyl ester, isolated from Katsura-uri (Japanese pickling melon, Cucumis melo var. conomon), enhanced differentiation in human colon cancer cells

The fully ripened fruit of Katsura-uri Japanese pickling melon ( Cucumis melo var. conomon) has rarely been used for food because the midripened fruit is utilized for making pickles, but the fully ripened fruit is no longer valuable for pickles due to the fruit body being too soft. We have considered the utilization of the fully ripened Katsura-uri fruit that may be used for nonpickling products, particularly if the fully ripened fruit demonstrated health benefits such as anticarcinogenic properties. The phytochemical extract from the fully ripened fruit of Katsura-uri Japanese pickling melon was purified via a bioassay-guided fractionation scheme, which was based on the induction of differentiation in a RCM-1 human colon cancer cell line. On the criteria of two differentiation markers (duct formation and alkaline phosphatase activity), the most potent fraction contained a compound identified as 3-methylthiopropionic acid ethyl ester, based on GC retention time, EI-MS, (1)H NMR, and (13)C NMR spectra. Previously, the role of 3-methylthiopropionic acid ethyl ester was considered as an odor producing compound in many fruits, but this study indicates potential medical benefits of this compound.

[A new phenylpropanoic acid derivatives from the roots of Ficus stenophylla]

Chemical constituents of the roots of Ficus stenophylla were isolated and purified by repeated column chromatography on silica gel and Sephadex LH-20. Their structures were elucidated based on physicochemical and spectral data. Five compounds were identified as methyl 3-(6-hydroxy-4-methoxybenzofuran-5-yl) propanoate (1), kaemferol (2), kampferol 3-O-beta-D-glucoside (3), quercetin (4) and tricin (5), separately. Compound 1 is a new phenylpropionic acid derivatives. All compounds were obtained from this plant for the first time.

Micromelones A and B, noncontiguous polypropionates from Micromelo undata

In this paper we report on the isolation and structural elucidation of two new noncontiguous polypropionates, micromelones A ( 10) and B ( 11), that have been isolated from the marine gastropod Micromelo undata. Their structures were determined through the interpretation of their spectroscopic data, and a biosynthetic pathway from a common linear precursor with other polypropionate groups has been proposed.

Identification of putative pheromones in bovine (Bos taurus) faeces in relation to estrus detection

Ten different volatile compounds were detected in bovine faeces using three chromatograms. The chemical profiles of estrus faeces were distinguished significantly from other phases by the presence of three specific substances, viz. acetic acid and propionic acid and 1-iodo undecane. The estrus specific synthetic compounds were rubbed onto the genital region of nonestrus animals (dummy cows), and the bulls were allowed to sniff the genital region and observed sexual behaviours. The statistical significance was higher (P<0.001) in bulls exhibiting repeated flehmen and mounting behaviours towards the mixture of acetic acid, propionic acid and 1-iodo undecane. The bioassay revealed that the fatty acids viz., acetic acid; propionic acid and 1-iodo undecane produced in faeces during estrus appear to be estrus specific. The results suggest that these compounds may be used as estrus indicator in cow, probably involved in bovine biocommunication.

Multicomponent Synthesis of 3-Indolepropionic Acids

A three-component one-pot procedure (3-MC) was developed to assemble 3-indolepropionic acids from commercially available materials. This new methodology affords the title compounds in high yields and without the use of chromatography. [reaction: see text].

Phenolic constituents from Perovskia atriplicifolia

Perovskoate, an isorinic acid derivative (1) and perovskoside, the catechol derivative (2) have been isolated from the ethyl acetate soluble fraction of the whole plant of Perovskia atriplicifolia and assigned the structure 3(7-hydroxyphenyl)-2-hydroxy propanoic acid; (R)-form, 2-O-(6',7'-dihydroxy-E-cinnamoyl) (1) and 2-methoxy-4-(undecyl-4'-O-beta-D-glucopyranosyl) phenol (2). In addition, caffeic acid (3) and ferulic acid (4) have been reported for the first time from this species. The structures of these compounds were assigned on the basis of 1D and 2D NMR techniques. The compound 1 showed significant inhibitory activity against lipoxygenase and weak to moderate activity against cholinesterases.

Enantioseparation of 2-aryloxypropionic acids on chiral porous monolithic columns by capillary electrochromatography

The enantioseparation of 2-aryloxypropionic acids by capillary electrochromatography was tested on columns with a monolithic stationary phase prepared from silanized fused-silica capillaries (100 microm I.D.) by in situ copolymerization of glycidyl methacrylate, ethylene glycol dimethacrylate and methyl methacrylate in the presence of formamide and 1-propanol as the porogen solvents. The porous chiral monolithic stationary phases were prepared by reaction of the epoxy-groups at the surface of the monolith with (+)-1-(4-aminobutyl)-(5R,8S,10R)-terguride. To attain the minimum HETP values for the enantiodiscrimination of 2-phenoxypropionic acid, the influence of the composition of polymerization solution on column total porosity and efficiency was investigated. Optimum mobile phase conditions were found for all analytes tested using acetonitrile-methanol mixtures containing triethylamine and acetic acid as the buffer components. Furthermore, the chemical and mechanical stabilities of the columns were satisfactory, allowing hundreds of analyses.

[The research of the pathogen responsible for Pleurocybella porrigens related encephalopathy: investigation of 3-nitropropionic acid hypothesis]

Pleurocybella porrigens related encephalopathy exhibits consciousness disturbance and convulsion in the patients after taking and patients show bilateral basal ganglia lesion resulted in high mortality rate. This encephalopathy is a very similar to the moldy sugarcane encephalopathy epidemic in China in the past. We investigated the relationship between Pleurocybella porrigens related encephalopathy and 3-nitropropionic acid which had caused the moldy sugarcane encephalopathy. We have tried to detect 3-NPA in the various specimens from patients and Pleurocybella porrigens, but failed. Further examinations for elucidating the causation of Pleurocybella porrigens related encephalopathy are needed.

Liquid chromatographic enantiomer resolution ofN-hydrazide derivatives of 2-aryloxypropionic acids on a crown ether derived chiral stationary phase

The liquid chromatographic separation of the enantiomers of several N-hydrazide derivatives of 2-aryloxypropionic acids was performed on a crown ether type chiral stationary phase derived from (18-crown-6)-2,3,11,12-tetracarboxylic acid. The behavior of chromatographic parameters by the change of mobile phases and additives for the resolution of these analytes was investigated. The enantiomers of all analytes were base-line resolved with a mobile phase of 100% methanol containing 20 mM H2SO4. These results are the first reported for enantiomer resolution of chiral acids of 2-aryloxypropionic acids as their N-hydrazide derivatives.

Acryloylated glucose 3-nitropropanoates from Indigofera kirilowii

Two unique glucose esters of 3-nitropropanoic acid with acryloyl moieties, kirilowin A and kirilowin B, were isolated from the roots of Indigofera kirilowii. Their structures were elucidated by detailed spectroscopic analysis. The two acrylates constitute new additions to the toxic glucose conjugates of 3-nitropropanoic acid in angiosperms.

Effects of non-ionic surfactants on isotachophoretic separations of 2-arylpropionic acids

Non-ionic surfactant (Brij 35, Tween 20, Tween 80 and Tergitol NPX) modified capillary isotachophoresis was investigated for the separation of 2-arylpropionic acids (fenoprofen, flurbiprofen, ibuprofen, ketoprofen and naproxen) and benzoic acid and its derivatives (salicylic, acetylsalicylic and gallic acids). The relative step height (RSH) values of analytes were found to be dependent on the type and concentration of the surfactant. The strength of the affinity of the 2-arylpropionic acids to the non-ionic micelles was found to be as follows: flurbiprofen > fenoprofen > ibuprofen > naproxen > ketoprofen. In general, the RSH values of 2-arylpropionic acids increase with an increase in the concentration of surfactants. However, the RSHs of benzoic, salicylic and gallic acids are not considerably affected. Separation of all acids was obtained with the Tween 20 (1.5%, w/v) in the leading electrolyte 10 mmol L(-1) hydrochloric acid/L-histidine (pH 6.0). Changes in the fluorescence intensity of fenoprofen, flurbiprofen and naproxen were also investigated in micellar media (Tween 20, Tween 80 and Brij 35). The strength of the affinity of the 2-arylpropionic acids to the Tweens micelles was found to be as follows: flurbiprofen > fenoprofen > naproxen, which is consistent with the isotachophoretic results. On the contrary, the strength of the affinity to the Brij micelles was found to be as follows: fenoprofen > naproxen > flurbiprofen.

3-Nitropropionic acid (3-NPA), a potent antimycobacterial agent from endophytic fungi: is 3-NPA in some plants produced by endophytes?

3-Nitropropionic acid (3-NPA, 1) was found in extracts of several strains of endophytic fungi. 3-NPA (1) exhibited potent antimycobacterial activity with the minimum inhibition concentration of 3.3 microM, but was inactive against NCI-H187, BC, KB, and Vero cell lines. Endophytes were found to produce high levels of 3-NPA (1), and therefore 3-NPA (1) accumulated in certain plants may be produced by the associated endophytes. 3-NPA (1) may be used as a chemotaxonomic marker for endophytic fungi. The structure of 3-hydroxypropionic acid, a nematicidal agent, should be revised to 3-NPA (1).

Synthesis and biological evaluation of a natural ester sintenin and its synthetic analogues

Synthesis of 3-(3,4-dimethoxyphenyl)propyl-3-(3,4-dimethoxyphenyl) propanoate (18), a cytotoxic natural ester, was carried out by a convenient synthetic path with a total yield of 49%. Sixteen of its analogues (19-34) were also prepared. Seventeen unsaturated derivatives of 18, compounds 1-17, were also synthesized to examine the structure-activity relationship of this type of ester. All of the synthetic compounds were passed through the cytotoxicity screenings on human tumor cell lines, such as PC-3, Hela, A549, BEL7404, CNE, and KB. Some of the esters exhibited moderate inhibitory effects on these tumor cell lines. The phenolic derivatives exhibited the highest cytotoxicity among these derivatives, while the unsaturated esters were more cytotoxic than the saturated analogues. Some of the compounds also exhibited inhibition on alpha-glucosidase.