A comparison between the enzymatic oxidation method and headspace gas chromatography with a flame ionization detector in the determination of postmortem blood ethanol.

Ethanol is the most commonly encountered substance in forensic toxicology. Determining blood alcohol concentration (BAC) in autopsies accounts for the majority of work in forensic diagnosis. The most common method to assess BAC is the enzymatic oxidation method because of its low cost, easy operation, and high throughput. Still, the elevated lactate and lactate dehydrogenase (LDH) levels in postmortem blood may affect accuracy. This study uses headspace gas chromatography with a flame ionization detector (HS-GC/FID) to assess the interference of lactate and LDH levels on BAC in 110 autopsied blood samples determined by the enzymatic oxidation method. The results showed that lactate and LDH levels in postmortem blood were higher than in normal blood. There was a weak correlation between the lactate levels and BAC difference (r = 0.23, p < 0.05) and a strong correlation between LDH levels and BAC difference (r = 0.67, p < 0.001). The differentiation of BAC between the enzymatic oxidation method and HS-GC/FID was significant (p < 0.001), confirming the interference significantly. All postmortem blood samples with lactate and LDH levels higher than regular lead to a positive error in determining BAC by enzymatic oxidation method. The study results suggest that the HS-GC/FID method should be used to determine BAC in postmortem blood samples instead of the enzymatic oxidation method to avoid mistakes in forensic diagnosis.

Constituents from the Fruiting Bodies of Trametes cubensis and Trametes suaveolens in Vietnam and Their Anti-Inflammatory Bioactivity.

It is reported that various fungi have been used for medicine and edible foods. The tropical Trametes genus is popular and well-known in Vietnam for its health effects and bioactivities. In this study, the fruiting bodies of the edible fungi T. cubensis and T. suaveolens were collected in Vietnam. The preliminary bioactivity screening data indicated that the methanol extracts of the fruiting bodies of T. cubensis and T. suaveolens displayed significant inhibition of superoxide anion generation and elastase release in human neutrophils. Therefore, the isolation and characterization were performed on these two species by a combination of chromatographic methods and spectrometric analysis. In total, twenty-four compounds were identified, and among these (1-3) were characterized by 1D-, 2D-NMR, and HRMS analytical data. In addition, the anti-inflammatory potentials of some purified compounds were examined by the cellular model for the inhibition of superoxide anion generation and elastase release in human neutrophils. Among the isolated compounds, (5,14), and (19) displayed significant anti-inflammatory potential. As the results suggest, the extracts and isolated compounds from T. cubensis and T. suaveolens are potential candidates for the further development of new anti-inflammatory lead drugs or natural healthy foods.

Chemical Constituents of the Leaves of Peltophorum pterocarpum and Their Bioactivity.

Two new sesquiterpenoids peltopterins A and B (compounds 1 and 2) and fifty-two known compounds were isolated from the methanol extract of P. pterocarpum and their chemical structures were established through spectroscopic and mass spectrometric analyses. The isolates 40, 43, 44, 47, 48, 51 and 52 exhibited potential inhibitory effects of superoxide anion generation or elastase release.

Chemical Constituents from the Stems of Tinospora sinensis and Their Bioactivity.

Fifty-seven compounds were purified from the stems of Tinospora sinensis, including three new compounds characterized as a lignan (1), a pyrrole alkaloid (11), and a benzenoid (17), respectively. Their structures were elucidated and established by various spectroscopic and spectrometric analytical methods. Among the isolates, fifteen compounds were examined for their anti-inflammatory potential in vitro. The results showed that several compounds displayed moderate inhibition of N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release.

Chemical Constituents from the Fruiting Bodies of Hexagonia apiaria and Their Anti-inflammatory Activity.

A chemical investigation of the fruiting bodies of Hexagonia apiaria resulted in the identification of nine compounds including five new triterpenoids, hexagonins A-E (1-5), along with four known compounds. The purified constituents were examined for their anti-inflammatory activity. Among the tested compounds, hexatenuin A displayed the most significant inhibition of superoxide anion generation and elastase release. These triterpenoids may have potentials as anti-inflammatory agents.

γ- and δ-Lactams from the Leaves of Clausena lansium.

Eight new clausenamides, including three γ-lactams (1-3), four δ-lactams (4-7), and an amide (8), and seven known lactams, including compounds 9-11, which were purified from natural sources for the first time, were characterized from the leaves of Clausena lansium. Their structures were elucidated using spectroscopic methods, and the absolute configurations were determined using electronic circular dichroism and single-crystal X-ray diffraction analyses with Cu Kα radiation. Compound 2 (50 µM) protected 22.24% of cortical neurons against Aß25-35-induced cell death.

Constituents of the roots of Clausena lansium and their potential anti-inflammatory activity.

Eight new carbazole alkaloids, claulamines C (1), D (2), and E (5) and clausenalines B-F (3, 4, 6-8), four new coumarins, clausemarins A-D (9-12), and 43 known compounds were isolated from the roots of Clausena lansium. The structures of the new compounds were established on the basis of 2D-NMR spectroscopic analysis, and their absolute configurations were established from their ECD spectra. The configuration of wampetin was revised as E using a NOESY experiment. Most of the isolated compounds were evaluated for their potential anti-inflammatory activity. The results showed that compounds 9, 13-18, and 20-22 exhibited strong inhibition of superoxide anion generation with IC50 values ranging from 1.9 to 8.4 µM, while compounds 18, 19, and 21 inhibited elastase release with IC50 values in the range from 2.0 to 6.9 µM.

Bioactive 6S-styryllactone constituents of Polyalthia parviflora.

Parvistones A-E (1-5), five new styryllactones possessing a rare α,ß-lactone moiety and a 6S configuration, were isolated from a methanolic extract of Polyalthia parviflora leaves. The structures and the absolute configuration of the isolates were elucidated using NMR spectroscopy, specific rotation, circular dichroism, and X-ray single-crystal analysis. Compounds 8, 9, 11, and 12 were isolated for the first time. The results were supported by comparing the data measured to those of 6R-styryllactones. Moreover, a plausible biogenetic pathway of the isolated compounds was proposed. The structure-activity relationship of the compounds in an in vitro anti-inflammatory assay revealed the 6S-styryllactones to be more potent than the 6R derivatives. However, the effect was opposite regarding their cytotoxic activity. In addition, 6S-styrylpyrones isolated showed more potent anti-inflammatory and cytotoxic activity when compared to the 1S-phenylpyranopyrones obtained.

Synthesis and antibacterial activity of analogs of 5-arylidene-3-(4-methylcoumarin-7-yloxyacetylamino)-2-thioxo-1,3-thiazoli-din-4-one.

In an effort to develop new antimicrobial agents, 3-(4-methylcoumarin-7-yloxyacetylamino)-2-thioxo-1,3-thiazolidin-4-one (4) was synthesized by reaction of thiocarbonylbisthioglycolic acid with ethyl (4-methyl-2-oxo-2H-chromen-7-yloxy)aceto- hydrazide (3), which was prepared in turn from 7-hydroxy-4-methylcoumarin (1). The condensation of compound 4 with different aromatic aldehydes afforded a series of 5-(arylidene)-3-(4-methylcoumarin-7-yloxyacetyl-amino)-2-thioxo-1,3-thiozolidin-4-one analogs 5a-h. The structures of these synthetic compounds were elucidated on the basis of IR, 1H-NMR and 13C-NMR spectral data and ESI-MS spectrometric analysis. Compounds 5a-h were examined for their antibacterial activity against several strains of Gram-positive and Gram-negative bacteria.

Anti-inflammatory diterpenoids from Croton tonkinensis.

Phytochemical investigation of the methanolic extract of Croton tonkinensis afforded two known kauranes (1, 2), eight new ent-kauranes (3-10), and 16 known ent-kaurane-type diterpenoids (12-27). In addition, 30 known compounds were identified by comparison of their physical and spectroscopic data with reported data. Among the isolated compounds, ent-18-acetoxykaur-16-en-15-one (20) displayed the most significant inhibition of superoxide anion generation and elastase release.

Isolation and synthesis of melodamide A, a new anti-inflammatory phenolic amide from the leaves of Melodorum fruticosum.

Together with twelve known compounds (2-13), melodamide A (1), a new phenolic amide possessing p-quinol moiety, was purified and characterized from the methanolic extracts of the leaves of Melodorum fruticosum. The structure of melodamide A (1) was established with a combination of 2D NMR experiments, HR-ESI-MS and X-ray analyses. The other known compounds were identified by comparison of their spectroscopic and physical data with those reported in the literature. Moreover, some isolated compounds were examined for their inhibitory activity towards superoxide anion generation and elastase release in human neutrophils. Among the tested compounds, 1, 3, and 5 exhibited strong inhibition of superoxide anion generation with IC50 values ranging from 5.25 to 8.65 µM. Furthermore, synthesis and biological evaluation of melodamide A (1) and its analogs (14a-p) were described.

Chemical constituents from the leaves of Annona reticulata and their inhibitory effects on NO production.

In the present study, the chemical investigation of the leaves of Annona reticulata has resulted in the identification of nine compounds, including annonaretin A, a new triterpenoid. The purified compounds were subjected to the examination of their effects on NO inhibition in LPS-activated mouse peritoneal macrophages and most of them exhibited significant NO inhibition, with IC50 values in the range of 48.6 ± 1.2 and 99.8 ± 0.4 µM.

Triterpenoids and steroids from Ganoderma mastoporum and their inhibitory effects on superoxide anion generation and elastase release.

The methanol extracts of the fruiting bodies of Ganoderma mastoporum collected in Vietnam was purified to afford eight compounds, including three triterpenoids and five steroids. The purified compounds were examined for their inhibitory effects against superoxide anion generation and elastase release. Among the tested compounds, ergosta-4,6,8(14),22-tetraen-3-one (3) exhibited the most significant inhibition towards superoxide anion generation and elastase release with IC50 values of 2.30 ± 0.38 and 1.94 ± 0.50 µg/mL, respectively.

Anti-inflammatory and Antiphytopathogenic Fungal Activity of 2,3-seco-Tirucallane Triterpenoids Meliadubins A and B from Melia dubia Cav. Barks with ChemGPS-NP and In Silico Prediction.

Two new rearranged 2,3-seco-tirucallane triterpenoids, meliadubins A (1) and B (2), along with four known compounds, 3-6, were isolated from the barks of Melia dubia Cav. Compound 2 exhibited a significant inflammatory inhibition effect toward superoxide anion generation in human neutrophils (EC50 at 5.54 ± 0.36 µM). It bound to active sites of a human inducible nitric oxide synthase (3E7G) through interactions with the residues of GLU377 and PRO350, which may benefit in reducing the neutrophilic inflammation effect. The ChemGPS-NP interpretation combined with bioactivity assay and in silico prediction results suggested 2 to be an agent for targeting iNOS with different mechanisms as compared to a selected set of current approved drugs. Moreover, compounds 1 and 2 showed remarkable inhibition against the rice pathogenic fungus Magnaporthe oryzae in a dose-dependent manner with IC50 values of 137.20 ± 9.55 and 182.50 ± 18.27 µM, respectively. Both 1 and 2 displayed interactions with the residue of TYR223, a key active site of trihydroxynaphthalene reductase (1YBV). The interpretation of 1 and 2 in the ChemGPS-NP physical-chemical property space indicated that both compounds are quite different compared to all members of a selected set of reference compounds. In light of demonstrated biological activity and in silico prediction experiments, both compounds possibly exhibited activity against phytopathogenic fungi via a novel mode of action.

Drimane-type sesquiterpenes with a dioxabicyclooctane skeleton from the fruiting bodies of Nigrofomes melanoporus and their cytotoxicity.

Two new drimane-type compounds, nigrofomins A ( 1) and B ( 2), possessing a rare dioxabicyclooctane moiety, were purified from the fruiting bodies of Nigrofomes melanoporus. Their structures were determined using 1D-, 2D-NMR and HR-ESI-MS spectroscopic analyses. In addition, 1 was established by X-ray crystallographic studies. Both nigrofomins A ( 1) and B ( 2) exhibited cytotoxicity on acute T-cell leukemia (Jurkat), human nasopharyngeal carcinoma (NPC-TW01), and lung cancer (NCI-H661) cells with IC (50) values in the range of 99.44-246.32 µM. Furthermore, the effects of 1 and 2 on cell-cycle progression of Jurkat cells displayed a concentration-dependent accumulation in the G (0)/G (1) phase.

New flavan and benzil isolated from Fissistigma latifolium.

Further investigation of the methanolic extract of Fissistigma latifolium resulted in two new compounds whose structures were assigned as 2,5,6,7-tetramethoxyflavan (1) and 2'-hydroxy-4',5',6'-trimethoxybenzil (2). These two compounds were determined on the basis of chemical and spectroscopic evidences. Compound 2 is the first report of benzil from Fissistigma species. 2,5,6,7-Tetramethoxyflavan (1) showed a potent inhibitory effect on superoxide anion production in formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP)/cytochalasin B (CB)-activated human neutrophils.

Chemical Composition Analysis and Antioxidant Activity of Coffea robusta Monofloral Honeys from Vietnam.

Monofloral honey samples (Coffea robusta) from Vietnam were determined for their chemical compositions. This is the first report on the chemical composition and antioxidant activity of coffee honey from Vietnam. These samples were characterized by their high contents of total and reducing sugars, total phenolic contents, and total flavonoid contents. The contents of seven phenolic acids (PAs) were quantified by high performance liquid chromatography (HPLC) and analyzed with the assistance of principle component analysis (PCA) to differentiate the honey samples into groups. The hydroxymethylfurfural (HMF) (0.048-2.933 mg/kg) and free acid contents (20.326-31.163 meq/kg) of coffee honey were lower in Nepal, which reflected the freshness of the honey when conducting this survey. The coffee honey had total sugar and reducing sugar contents 831.711 g/kg and 697.903 g/kg, respectively. The high level of total phenolic (0.642 mg GAE/g) and flavonoid (0.0341 mg GE/g) contents of coffee honey contributed to their antioxidant activity of this honey sample. Among the coffee honey tested, the IC50 of DPPH radical-scavenging activities value was 1.134-17.031 mg/mL, while the IC50 of ABTS radical-scavenging activities value was 115.381-213.769 mg/mL. The phenolic acids composition analysis displayed that gallic acid appeared in high concentrations in all studied honey samples, ranging from 0.037-1.015 mg/kg, and ferulic acid content ranged from 0.193 to 0.276 mg/kg. The content of trigonelline and caffeine in coffee honey samples ranged from 0.314-2.399 mg/kg and 8.946-37.977 mg/kg. The data in this article highlight the relevance of coffee honey as a healthy substance.

Inhibition of α-Glucosidase, Acetylcholinesterase, and Nitric Oxide Production by Phytochemicals Isolated from Millettia speciosa-In Vitro and Molecular Docking Studies.

The phytochemical constituents from the roots of Millettia speciosa were investigated by chromatographic isolation, and their chemical structures were characterized using the MS and NMR spectroscopic methods. A total of 10 compounds, including six triterpenoids, two flavonoids, and two phenolic compounds, were identified from the roots of M. speciosa. Out of the isolated compounds, eight showed inhibitory effects on NO production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells, with IC50 values ranging from 43.9 to 449.5 µg/mL. Ursane-type triterpenes significantly suppressed NO production compared to the remaining compounds. In addition, these compounds also exhibited remarkable inhibitory effects on α-glucosidase. Among the tested compounds, 4, 5, and 10 exhibited excellent α-glucosidase inhibition, with IC50 values ranging from 1.1 to 2.2 µg/mL. Almost all of the test compounds showed little or no acetylcholinesterase inhibition, except for 5, which showed moderate anti-acetylcholinesterase activity in vitro. The molecular docking study of α-glucosidase inhibition by 3-5 and 10 was conducted to observe the interactions of these molecules with the enzyme. Compounds 4, 5, and 10 exhibited a better binding affinity toward the targeted receptor and the H-bond interactions located at the entrance of the enzyme active site pocket in comparison to those of 3 and the positive control acarbose. Our findings evidence the pharmacological potential of this species and suggest that the phytochemicals derived from the roots of M. speciosa may be promising lead molecules for further studies on the development of anti-inflammatory and anti-diabetes drugs.

The first bis-retrochalcone from Fissistigma latifolium.

Two novel chalconoids, [3-3'']bi-2-hydroxy-4,5,6-trimethoxydihydrochalcone (1) and 4,6-dimethoxy-2,5-quinodihydrochalcone (2), and twelve known compounds were isolated from the methanolic extract of Fissistigma latifolium (Dun.) Merr. The structures of all compounds were determined by spectroscopic methods. Of these, compounds 1, 2, and 2-hydroxy-4,5,6-trimethoxydihydrochalcone (10) belong to an uncommon group of chalconoids, the retrochalcones. Compound 1 is the first bis-retrochalcone to be reported, and compound 2 is a quinoretrochalcone. Furthermore, 2 showed activity against the MDA-MB-231 human breast cancer cell line with an IC (50) value of 7.1 µM.

An overview of the chemical composition and biological activities of essential oils from Alpinia genus (Zingiberaceae).

Alpinia Roxb. is the largest genus of the Zingiberaceae family. A large number of Alpinia species has been used as food and traditional medicines. Alpinia essential oils have been studied for their chemical profiles, in which 1,8-cineole, ß-pinene, α-pinene, ß-myrcene, camphor, γ-terpinene, p-cymene, geraniol, α-fenchyl acetate, ocimene, methyl cinnamate, and ß-caryophyllene have been found to be the major compounds. Essential oils isolated from Alpinia plants have been reported to have antimicrobial, cytotoxic, antioxidant, anti-inflammatory, anti-asthmatic, tyrosinase inhibitory, insecticidal, and larvicidal activities and slimming aromatherapy. In this review, the comprehensive information regarding the volatile components of various Alpinia plants, the bioactivities of Alpinia essential oils and their major compounds are provided.