Natural Product Research最新文献

Two new chromones, oleracone H (1) and oleracone I (2), were isolated from Portulaca oleracea L. and identified by UV, IR, UHPLC-ESI-QTOF/MS, 1D NMR, 2D NMR, and CD spectra. In 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical quenching assay, oleracone H (1) and oleracone I (2) presented scavenging activities with IC₅₀ values (half maximal inhibitory concentration) of 16.33 ± 0.20 μM and 22.36 ± 0.41 μM and the abilities of inhibiting the inflammatory factors IL-1β and TNF-α of the two compounds were superior to that of the positive control at 10 μM.

The extract of the stems of Eurya chinensis R. Br. yielded three new terpenes (1-3) including two diterpenes and one triterpene, named euryachins C-E, as well as three known diterpenes (4-6). The structures of these novel compounds were elucidated via spectroscopic analysis, especially IR, NMR spectroscopy and HRESIMS data. Besides, all the isolated compounds were evaluated for antibacterial activity against Escherichia coli, Bacillus cereus, Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA). Additionally, the inhibitive activity of the isolated compounds against COVID-19 was studied in vitro. As a result, compounds 1-6 were endowed with profound antibacterial activity. Especially, the MIC values of compounds 3 and 5 both were 0.78 µg/mL, the same antibacterial activity as Vancomycin. In the anti-COVID-19 assay, the IC₅₀ values of compounds 3-5 were ranging from 4 to 8 µM, which were equivalent to the positive control.

Citronella oil, extracted from Cymbopogon species (winterianus and nardus) is a commercially valuable essential oil used in personal-care products and insect repellents. Routine analysis in gas chromatography is incapable of detecting high-boiling adulterants therein. In this study, an HPTLC technique was developed for the absolute quantification of citronellal (characteristic chemical marker) and triglyceride (main constituent of vegetable oil adulterant) in citronella oil for its quality assessment. It was validated in terms of specificity, linearity, sensitivity, accuracy and precision. Further, the developed method was employed to quantify citronellal and triglyceride in twenty commercial samples. The results showed a wide variation in citronellal content (trace to 30.65% w/w) and could differentiate its two chemotypes. Also, it revealed the possibility of vegetable oil adulteration through the detection and quantification of triglyceride in selected samples. It can be a simple and rapid technique for the quality control of citronella oil.

A preliminary screening test was performed to discover new antihyperlipidaemic active compounds from the leguminous plant Derris eriocarpa How. A new compound, derris-isoflavone F (1), and derrubone dimethyl ether (6), a known synthetic compound of natural origin, were isolated from the stems of D. eriocarpa alongside eight recognised compounds. To our knowledge, this is the first instance of documenting the identification of compounds 1-10 from this plant. The new compound were evaluated for their antihyperlipidemic and antiproliferative properties. Compound 1 evidently reduced the triglyceride (TG) content in oleic acid-treated HepG2 cells, which validated its efficacy as a potential TG-lowering agent.

The present investigation was carried out to characterise bioactive components from G. senegalensis by using Fourier-transform infra-red (FT-IR) spectroscopy, ¹H-nuclear magnetic resonance spectroscopy, and gas chromatography-mass spectrometry (GC-MS). The FTIR analysis confirmed the presence of > CH₂, -CH₃, C = C-C, C-H, C-F, C = C, -C = N-, C-C = N-, and -OH functional groups. The ¹H-NMR spectrum revealed the presence of structures of four bioactive compounds i.e. tetratetracontana derivative, β-carotene, amyrin, and terpineol. GC-MS revealed the presence of different types of high and low molecular weight chemical entities with varying quantities including volatile and essential oil, monoterpenoid, tetraterpenoid, carotenoid, terpenoid, triterpenes, and nortriterpenes. From the results, it could be concluded that G. senegalensis contains various bioactive compounds of biological and pharmacological importance. Overall, this study will provide insight into the characterisation and development of drugs from medicinal plants.

Two new naphthoquinones, 7-hydroxy-2-O-methyldunniol (1) and 7-methoxy-2-O-methyldunniol (2) were isolated from the tubers of Sinningia conspicua (Seem.) G. Nicholson (Gesneriaceae). Nine known compounds were also obtained: 7-methoxydunniol (3), dunniol (4), 7-methoxy-α-dunnione (5), 7-hydroxydunnione (6), 2,4,4',6-tetramethoxychalcone (7), loureirin B (8), allo-calceolarioside A (9), β-sitosterol (10) and stigmasterol (11). This is the first report of compounds 3 and 5 in Sinningia. n-Hexane, ethyl acetate and ethanol extracts, and compounds 1-5 were tested for cytotoxic activity against PC-3 (prostate) and SKMEL 103 (melanoma) human tumour cell lines and also against the 3T3 (fibroblast) non-cancer cell line. All samples were inactive.

Liver cancer is one of the most common lethal malignancy in the world. To treat liver cancer, new cure options are crucial. The use of natural substances along nanosciences may provide healing with lower toxicity and a smaller amount of side properties. In this research, The three-component selenium-silver-chitosan nanocomposite (Se-Ag-CS NCs) were synthesised with the help of ultrasound in a stepwise manner. The as-synthesised Se-Ag-CS NCs were characterised accordingly by applying powder X-Ray diffraction (PXRD), Fourier transforms infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive x-ray analysis (EDX), transmission electron microscopy (TEM), dynamic light scattering (DLS) and potential. The PXRD demonstrated that the NCs were synthesised successfully and the grain sizes of 27.3 were obtained. The FESEM and TEM analyses have shown the NCs have a nano-sized structure with spherical and rod-like morphologies in a coating of CS. The DLS analysis also revealed that NCs were synthesised in nanoscale particles. The NCs' surface charge was also positive due to the presence of chitosan. Different concentrations of NCs (0, 0.125, 0.250, 0.500, and 1 mg/ml) were tested at different times (24, 48, and 72 h) to measure cytotoxicity against liver cancer cells. The results showed at a concentration of 1 mg/mL in 72 h, the most toxicity effects were applied to liver cancer cells. Moreover, the results indicated NCs can inhibit the growth of cancer cells in a dose-dependent manner, while the toxicity of nanocomposite on normal cells was less. It is important to create nanocomposites derived from natural polymers as a new strategy in cancer treatment that can fight cancer cells while having low toxicity for normal cells. Therefore, the present results can be considered in improving cancer-fighting methods.

The past decade has seen increasing interest in plant oils in the food, pharmaceutical, and cosmetic industries due to their diverse functional and nutritional properties, as well as the high levels of consumer acceptance. As a result, there has been a spike in research interest in finding new sources of oils with good potential for industrial use. In this paper, the chemical characterisation (saponification, iodine, acid and ester numbers, as well as fatty acid composition) of nettle seed oil was given. Oil was analysed for its thermooxidative stability by differential scanning calorimetry. The kinetic parameters of oxidation (Ea, A, and k) were also determined. The results showed that nettle seed oil belongs to the group of edible oils of the linoleic type and it is nutritionally highly valuable, it has pronounced thermooxidative stability and could be an alternative source of raw material for the food, cosmetics, and other non-food industries.

Two metal chelates of Dioscorea oppositifolia L. peel polysaccharides (DTP) were prepared: iron chelate (DTP-Fe) and zinc chelate (DTP-Zn). The physicochemical properties of the polysaccharide and its metal chelates were assessed by UV-Vis absorption spectroscopy, Fourier-transform infra-red spectroscopy, scanning electron microscopy, and thermogravimetric analysis. Antioxidant activities were evaluated by DPPH, ABTS + and hydroxyl radical scavenging assays. According to ICP-MS, the iron content of DTP-Fe was 9.47%, while the zinc content of DTP-Zn was 4.02%. The antioxidant capacity of DTP-Fe increased with the increase of concentration, and its overall activity was higher than that of DTP and DTP-Zn. This polysaccharide-iron chelate can be developed and utilised as an antioxidant and multifunctional iron supplement. DTP-Zn showed the potential to be a natural antioxidant and zinc supplement food.

Methanolic extracts of Gleditsia triacanthos L. fruits and Gleditsia caspica Desf. leaves yielded two mono-carbonyl curcumin analogues; (1E,4E)-1,5-bis(4-hydroxy-3-methoxyphenyl)penta-1,4-dien-3-one [1], (1E,4E)-1,5-bis(4-hydroxyphenyl)penta-1,4-dien-3-one [2], in addition to β-sitosterol [3], apigenin [4], quercetin-3`-O-methyl ether [5], rutin [6], quercetin [7], naringenin [8], eriodictyol [9], vitexin [10], isovitexin [11], gleditsin A [12]. The isolation of these compounds was reported here for the first time from the named plants. The separation and identification of curcumin analogues from genus Gleditsia in addition to ¹³C NMR data of compound 2 were reported here for the first time. Compounds 1 and 2 were assayed in two hepatic cancer cells; HepG-2 and Huh-7. Compound 1 showed high cytotoxic activity against HepG-2 with an IC₅₀ value of 14.39 µM, compared with the standard, IC₅₀ = 12.44 μM.