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A phytochemical study of the roots of Brucea javanica was conducted and four alkaloids and three quassinoids were isolated. The structures of the compounds were verified using physical and spectroscopic data, which were compared to the literature. The cytotoxicity of the compounds was evaluated against KB (oral cavity carcinoma), NCI-H187 (small cell lung cancer), and MCF-7 (breast adenocarcinoma) cell lines. The results showed that the quassinoid, Bruceine A, exhibited very strong cytotoxicity against KB, and high potency against NCI-H187, with both being 581- and 100-fold more active than ellipticine, and 99- and 10-fold more active than doxorubicin, respectively. These results suggest the potential use of bruceine A as an anticancer agent. [ABSTRACT FROM AUTHOR]

Six new abietane diterpenes, roscoeananes A-F ( 1 - 6 ), along with two known compounds ( 7 - 8 ) were isolated from the rhizomes of Kaempferia roscoeana . The structures of all compounds were elucidated by analysis of spectroscopic data, and the absolute configurations were assigned by a comparison of the theoretical and experimental electronic circular dichroism (ECD) spectra and a comparison with literature values. The unreported compound 5 is an ether-linked dimer of roscoeanane B ( 2 ). Most of the isolated compounds were tested for their nitric oxide inhibitory effects in lipopolysaccharide-activated RAW264.7 cells. Among them, roscoeanane A ( 1 ) was found to reduce NO levels in murine macrophage cells with an IC 50 value of 3.58 ± 0.95 μM and exhibited low cytotoxicity (IC 50 > 50 μM).

Nitrophenols (NPs) have significant impacts on human health, climate, and atmospheric chemistry. Despite numerous measurements of particulate NPs, still little is known about their gaseous atmospheric abundances, sources, and fate. Here, four gaseous NPs [2,4-dinitrophenol (2,4-DNP), 4-nitrophenol (4-NP), 2-nitrophenol (2-NP), and 2-Methyl-4-nitrophenol (2-Me-4-NP)] were continuously monitored during late Spring at an urban site in Houston, Texas. Among the four NPs, 4-NP showed the highest abundance, followed by 2-Me-4-NP, 2-NP, and 2,4-DNP with average concentrations of 1.07 ± 0.19 ppt, 0.47 ± 0.12 ppt, 0.41 ± 0.16 ppt, and 0.27 ± 0.09 ppt, respectively. The positive matrix factorization (PMF) model identified seven sources: industrial NPs, secondary formation, phenol sources, acetonitrile source, natural gas/crude oil, traffic, and petrochemical industries/oil refineries. A zero-dimensional photochemical box model was used to simulate the observed 2-NP and 2,4-DNP. A 50.0% and 70.0% jNO 2 was found to be consistent with the measured 2-NP and 2,4-DNP. This yields a nitrous acid (HONO) production of 7.5 ± 2.5 ppt/h from 06:00 to 18:00 Central Standard Time (CST) from both NPs. An extrapolation including other known NPs suggests a maximum HONO formation of 13.8 ppt/h. The results of this study suggest that using PMF analysis supplemented by photochemical box model provides identification of the NPs sources and their atmospheric implication to HONO formation., Competing Interests: Declaration of competing interest The authors declare that they have no competing personal relationships or financial interests that could have appeared to influence the work reported in this current paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Two new cassane diterpenoids, 14β-hydroxycassa-11(12),13(15)-dien-12,16-olide ( 1 ) and 6'-acetoxypterolobirin B ( 3 ), together with a known analogue, identified as 12α,14β-dihydroxycassa-13(15)-en-12,16-olide ( 2 ), were isolated from the fruits of Pterolobium macropterum . Compound 1 is a cassane diterpenoid with a Δ 11(12) double bond conjugated with an α,β-butenolide-type, whereas compound 3 is a dimeric caged cassane diterpenoid with unique 6/6/6/6/6/5/6/6/6 nonacyclic ring system. The structures of 1 and 3 were characterized by extensive spectroscopic analysis combined with computational ECD analyses. The α-glucosidase inhibitory activity of isolated compounds was evaluated, and compounds 1 and 3 showed significant α-glucosidase inhibitory activity with IC 50 values of 66 and 44 μM., (Copyright © 2023, Cheenpracha et al.)

Marginaols G-M, a series of undescribed isopimarane diterpenoids, together with four known analogs were isolated from the rhizomes of Kaempferia marginata. The structures of these isolated compounds were characterized using high-resolution mass spectrometry and extensive 1D- and 2D-nuclear magnetic resonance (NMR) analyses. In addition, the absolute configurations of marginaol G and H were determined by X-ray crystallographic analysis and comparison with the literature values. When compared to the standard drug dexamethasone (IC 50 4.7 μM), marginaol G, H, and 6β-acetoxysandaracopimaradien-1α,9α-diol had an intriguing anti-inflammatory effect on NO inhibition in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages, with IC 50 values ranging from 4.5 to 7.3 μM and being less cytotoxic to the cells. The anti-inflammatory action of these isopimarane diterpenoids from K. marginata supports the use of Thai traditional medicine for inflammation treatment., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The isopimarane diterpene, 1α,11α-dihydroxyisopimara-8(14),15-diene (1), is the major constituents from the rhizomes of Kaempferia marginata (Zingiberaceae), a Thai medicinal plant. The microbial transformation of parent compound 1 by the fungus Cunninghamella echinulata NRRL 1386 gave five new metabolites, 7α,11α-dihydroxy-1-oxoisopimara-8(14),15-diene (2), 3β,7α,11α-trihydroxy-1-oxoisopimara-8(14),15-diene (3), 7β,11α-dihydroxy-1-oxoisopimara-8(14),15-diene (4), 7α-hydroxy-1,11-dioxoisopimara-8(14),15-diene (5) and 1α,7β,11α-trihydroxyisopimara-8(14),15-diene (6), together with three known metabolites, 7-9. The structures of the new metabolites were elucidated by spectroscopic techniques. The known compounds were identified by comparison of the spectroscopic and physical data with those of reported values. The parent compound 1 and the metabolites have been neuroprotective activities evaluated against Aβ 25-35 -induced damage in human neuroblastoma cells (SK-N-SH). Among them, compounds 1-3, 5 and 7-9 had significant neuroprotective activities at a concentration of 2.5 μM. The results demonstrated that these compounds might be worth for further development into therapeutic agents for the treatment of neurodegenerative diseases., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Six new isopimarane diterpenes, marginaols A-F ( 1 - 6 ), along with eight known compounds ( 7 - 14 ), were isolated from the rhizomes of Kaempferia marginata . The structures and absolute configurations of 1 - 6 were established on the basis of spectroscopic methods and the experimental and calculated ECD data as well as comparison with the literature values. Most of the isolated compounds were tested for their nitric oxide (NO) inhibitory effects in lipopolysaccharide-activated RAW264.7 cells. Among them, marginaol B ( 2 ) was found to reduce NO levels in murine macrophage cells with an IC 50 value of 28.1 ± 1.7 μM.

The diterpene isocoronarin D ( 1 ) is a bioactive major constituent of labdane diterpene from the aerial parts of Curcuma comosa Roxb. (Zingiberaceae), the Thai medicinal plant. Microbial transformation of 1 was performed by the fungus Cunninghamella echinulata NRRL 1386 to yield three new metabolites, 3 β -hydroxyisocoronarin D ( 2 ), 6 α -hydroxyisocoronarin D ( 3 ) and 3 β ,7 α -dihydroxyisocoronarin D ( 4 ). The structures of the new compounds were elucidated by spectroscopic techniques.

Simple simultaneous determination of iron and manganese by sequential injection spectrophotometry using astilbin extracted from Smilax china L. root is proposed. It is based on the kinetic difference of the complexation of the ions and astilbin. With a simple sequential injection system, the simultaneous determination can be performed at pH 10 and can be followed at a wavelength of 440 nm. A throughput of 12 samples per hour was obtained with detection limits (3σ) of 0.05 mg L -1 iron(III) and 0.20 mg L -1 manganese(II), respectively. Application of the proposed system to real ground water sample was demonstrated. The results agreed with that of the atomic absorption spectrophotometric reference method., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Acacia pennata subsp insuavis, or Cha-om in Thai, is a common vegetable found in Thailand. It has been used as a medicinal herb for a long time. From the literature, antinociceptive, anti-inflammatory, antimicrobial, and anti-helminthic activities were reported. In this study, we investigated two new actions of this plant: larvicide and pupicide. The crude ethanolic and fractionated extracts of A. pennata shoot tips were tested against aquatic stages of the dengue virus vector, Aedes aegypti mosquito. The 1st-4th instar larvae and pupae of Ae. aegypti were subjected for bioassays by following the standard protocol of WHO. The larval and pupal mortalities were observed after 24- and 48-hour exposure times. The bioassays demonstrated that stronger efficacy was found from the fractionated extracts than the crude extracts. The LC50 values against the 3rd instar larvae were 39.45-50.75 mg/l (fractionated extracts) and 244.50 mg/l (crude extracts). It also effects the pupae with the LC50 values of 44.10-53.73 mg/l and 87.27 mg/l for the fractionnated and the crude extracts, respectively. The bioassays demonstrated the effective mosquito larvicide and pupicide of A. pennata extracts. It could be an alternative candidate for the development of phytotoxin for controlling mosquito vectors.

The use of insecticides can cause adverse effects in vector control, a plant bio-insecticide is an advantageous substitute. Currently, the promising mosquito larvicidal activity from plant extracts has been reported worldwide, including Thailand. In this study, the endocarp of Pereskia bleo (Kunth) DC. fruit was extracted with distilled water and ethanol. Crudes and fractionated groups of the extracts were evaluated for their larvicidal efficacy against the 3rd instar larvae of Aedes aegypti. At 48 hours of exposure, it was found that the activities of the extracts were higher than 24-hour's. The ethanolic extracts showed stronger activities than the aqueous ones, indicating the lower LC50 values of both crude and fractionated group extracts. The most toxic activity was found in a fractionated group of the ethanolic extract, E-Gr3, with significantly lowest LC50 values of 707.94 and 223.12 ppm for 24- and 48-hour detection times, respectively. The bioassay results indicated the larvicidal property against the Ae. aegypti mosquito of the P. bleo plant extracts. A safety for non-target organisms or an action on other mosquito vectors of this plant, should be further investigated.

We report a novel system to analyze atmospheric nitrophenols (NPs). Rain or air sample extracts (1 mL) are preconcentrated on a narrow bore (2 mm) aliphatic anion exchanger. In the absence of strong retention of NPs exhibited by aromatic ion exchangers, retained NPs are eluted as a plug by injection of 100 microL of 0.1 M Na(2)SO(4) on to a short (2 x 50 mm) reverse phase C-18 column packed with 2.2 mum particles. The salt plug passes through the C-18 column unretained while the NPs are separated by an ammonium acetate buffered methanol-water eluent, compatible with mass spectrometry (MS). The eluted NPs are measured with a long path Teflon AF-based liquid core waveguide (0.15 x 1420 mm) illuminated by a 403 nm light emitting diode and detected by a monolithic photodiode-operational amplifier. The waveguide is rendered chemically active by suspending it over concentrated ammonia that permeates into the lumen. The NPs ionize to the yellow anion form (lambda(max) approximately 400 nm). The separation of 4-nitrophenol, 2,4-dinitrophenol, 2-methyl-4-nitrophenol, 3-methyl-4-nitrophenol, and 2-nitrophenol (these are the dominant NPs, typically in that order, in both rain and air of Houston and Arlington, TX, confirmed by tandem MS) takes just over 5 min with respective S/N = 3 limits of detection (LODs) of 60, 12, 30, 67, and 23 pg/mL compared to MS/MS LODs of 20, 49, 11, 20, and 210 pg/mL. Illustrative air and rain data are presented.

Alkaline phosphatase (ALP) has been used as one of the biomarkers for bone resorption and liver diseases. Normally, total alkaline phosphatase is quantified along with other symptoms to determine the releasing source of the alkaline phosphatase. A semi-automated flow injection-bead injection system was proposed to conveniently and selectively assay bone alkaline phosphatase (BALP) based on its specific binding to wheat germ coated beads. Amount of BALP in serum was determined from the intensity of the yellow product produced from bound BALP on the retained beads and its substrate pNPP. The used beads were discarded and the fresh ones were introduced for the next analysis. The reaction cell was designed to be opened and closed using a computer controlled solenoid valve for a precise incubation time. The performance of the proposed system was evaluated by using it to assay BALP in human serum. The results were compared to those obtained by using a commercial ELISA kit. The system is proposed to be an easy and cost effective system for quantification of BALP as an alternative to batch wise wheat germ specific binding technique.

A simple spectrophotometric flow injection (FI) procedure for the determination of Cr(III) using ethylenediaminetetraacetic acid (EDTA) was developed. An FI system with a column packed with Amberlite IR-120(H) was employed for sample pretreatment. This leads to the possibility of a single standard calibration. A linear calibration in a range of 10-27 microg Cr(III) was obtained with a detection limit of 1 microg Cr(III) and RSD of 2% (18 microg Cr(III), n=12). The proposed procedure was applied for determination of Cr(III) in leachate and dietary supplement samples. The results agreed with those obtained by the standard methods.