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Background Leaves, flowers and young shoots of yellow Camellia species are often used as a substitute for green tea in Vietnam. Yellow Camellia species contain high levels of polyphenol compounds, and have shown activities such as antioxidant, anticancer, and cytotoxic. Objectives We qualitatively screened phytochemicals, quantified total polyphenols of 70% ethanol (EtOH) extracts of leaves, young shoots, and flowers of Camellia vuquangensis and Camellia hatinhensis in Ha Tinh Province, Vietnam. Furthermore, these extracts have been evaluated for lipid peroxidation inhibitory activities at the in vivo level in the BALB/c mouse model, and in vitro cytotoxic activities. Materials and Methods Chemical methods and thin-layer chromatographic (TLC) analysis were used for the qualitative screening of phytochemicals. High-performance liquid chromatography (HPLC) was used to determine total polyphenols. Cell survival was determined through optical density (OD) measured when the protein composition of the cells was stained with sulforhodamine B (SRB). Inhibition of lipid peroxidation was evaluated by determining the content of malondialdehyde (MDA), which is a product of membrane lipid peroxidation. Results The total polyphenol contents of all parts of the two species were comparable to that of green tea with values between 319.3 and 342.6 mg gallic acid equivalents (GAE/g) dry weight. Extracts of leaves, flowers of C. vuquangensis and C. hatinhensis showed strong lipid peroxidation inhibitory activities (IC50: 7.92–17.45 µg/mL) and moderate cytotoxic activities against cell lines HepG2, A549, MCF7, SK-Mel-2, HT-29, and AGS (IC50: 34.73–80.58 µg/mL). Conclusion These two tea species may be considered as herbal teas with various health benefits.

Cephalotaxus mannii Hook.f is a rare medicinal plant used for the treatment of leukemia, however, its fungal endophytes with antibacterial and anticancer properties have not been exploited yet. In this study, six fungal isolates were recovered from roots of C. mannii collected in Ha Giang province, Vietnam. Among them, ethyl acetate crude extract of strain WQF5 exhibited strong antibacterial activity against 5 tested pathogens with inhibition zones ranging from 13.0 ± 0.5 mm to 20.0 ± 0.4 mm. Sulforhodamine B assay showed that WQF5 extract possessed the most potent cytotoxic activity against lung cancer A549 and breast cancer MCF7 cell lines with IC50 values of 6.9 ± 0.7 µg/mL and 23.1 ± 1.9 µg/mL, respectively. PCR-based molecular marker screening revealed that the positive hits for essential genes encoding 10-deacetylbaccatin III-10-O-acetyltransferase (dbat) and C-13 phenylpropanoyl side chain-CoA acyltransferase (bapt) involved in paclitaxel production were found in the fungal isolate WQF5. In addition, isolate WQF5, identified as Fusarium fujikuroi by morphological and ITS analysis, also produced paclitaxel as shown by HPLC-DAD analysis. This is the first report of bioprospecting endophytic fungi isolated from C. mannii, in which the capability of producing paclitaxel of endophytic fungi was also proved for the first time. These findings addressed a potent candidate for paclitaxel production and provided excellent material for further investigations of how endophytic fungi from non-Taxus plant species synthesize paclitaxel.

Recently, the use of nanomaterials in industrial and technological applications for various fields is quickly growing. The “green” synthesis of metallic nanoparticles has received increasing attention due to the development of eco-friendly technologies. In our previous research, silver nanoparticles have been successfully prepared in gelatin (Ag/Gelatin sample), Gelatin/Chitosan (Ag/Gelatin/Chitosan sample) and chitosan (Ag/Chitosan sample) suspensions using a chemical reducing agent. For this purpose, biological grade gelatin and chitosan were used as reducing and stabilizing agents without special physical conditions. The most advantage of this work is using a renewable material like gelatin as a reducing factor, which is eco-friendly agent. However, one of the most important issues related to those nanofluids is their stability, and it remains as a big challenge to achieve desired applications in future. Thus, all obtained nanosilver samples were characterized by UV-Vis spectroscopy and evaluated the stability of antibacterial activity on Escherichia coli, Staphylococcus aureus. The absorption spectra results of the samples, which were measured after storage for three months, illustrated that the absorption peaks of the silver nanoparticles in Ag/Gelatin and Ag/Chitosan had shifted slightly from 423 to 425 nm and 435 to 440 nm, respectively. Whereas, the absorption peak for the Ag/Gelatin/Chitosan remained the same at 423 nm. In addition, after storage for three months, Ag/Gelatin/Chitosan sample showed antibacterial activity better than the two remaining samples with the reduction of inhibition zones is insignificant at 21.5 ± 0.25 mm while testing on Escherichia coli and at 15.5 ± 0.25 mm on Staphylococus aureus. The results suggested that silver nanoparticles were prepared in Gelatin/Chitosan composition showing promising stability and antibacterial activity which are beneficial for various/diversed/further applications.

Currently, multimode treatment is current therapy for cancer that causes various unwanted side effects and costliness for patients. Therefore, finding new natural ingredients derived from plants of which are less toxic and more targeted, are considered to be urgent for development of potential effective drugs to treat cancer due to safety and economic concerns. Physagulin P (VPA22) was known as a novel structural compound, isolated from the species Physalis angulata of the genus Physalis in Vietnam. This active substance has demonstrated cytotoxic effect on lung cancer cell line (A549) with the IC50 value = 13.47±2.73 µM. In our study, VPA 22 was investigated for apoptotic inducing activity on A549 cells by using Hoechst staining, flowcytometry analysis and caspase-3 colorimetric assay. VPA 22 treatment changed the morphology of A549 tending to apoptotic cells whose percentage ranged from 10.09% to 19.18% at the concentration of 5 µM and 15 µM, respectively. In addition, the active ingredient at concentration of 5 µM to 15 µM also significantly activated caspase-3 in turn from 1.30 folds to 2.59 folds. These results together indicated that VPA 22 activated the caspase pathway to trigger out apoptosis on A549 cells and subsequently resulted in inhibition of cancer cell proliferation.

Gynostemma pentaphyllum (Thunb.) Makino (GpM) is a medicinal plant in traditional medicine throughout Asia for the treatment of several diseases including cancer. GpM plant cell suspension cultures provide a time and cost effective well-controlled means promising a high-yielding biomass production of pharmaceutical compounds. The purpose of the current work is to investigate the effect of GpM cell suspension cultures on human cancer cell lines growth. The biomass was produced by cell suspension culture of GpM callus into 250 mL Erlenmeyer flask containing 50 mL of liquid medium culture. Gypenosides in GpM were confirmed by HPLC. Pharmacological activities of GpM extract were tested on human cancer cell line (HepG2, Huh7, A549 and HL-60) using Sulforhodamine B (SRB) cytotoxicity assay and Tetrazolium (MTT) assay. We successfully produced 5.485 ± 0.223 g GpM fresh biomass per 250 mL Erlenmeyer flask after 18 days culture. Total gypenosides and Rb1 in dry cell suspension were 48.844 ± 3.933 mg/g and 0.041 ± 0.004 mg/g. The crude extract from GpM cell suspension cultures exhibited significant cancerous cell growth inhibition in a dose dependent manner. From the MTT assay and SRB cytotoxicity assay, it is obvious that GpM cell suspension culture extract at 200 μg/mL significantly inhibited the growth of multiple human cancer cells including hepatoma cell lines (HepG2, Huh7), lung carcinoma cell line (A549) and leukemia cell line (HL-60). Anti-cancer cell proliferation properties of GpM cell suspension culture were significantly higher than those of natural plants’ extracts. In this framework, GpM in cell suspension cultures was found to inhibit the proliferation of several human cancer cells. Biomass accumulation of GpM in cell suspension cultures may contribute to the development of efficient strategies for plant-derived anticancer compound production.

Alkaloids are among the most important and best-known secondary metabolites as sources of new drugs from medicinal plants and marine organisms. A phytochemical investigation of whole Crinum asiaticum var. sinicum plants resulted in the isolation of seven alkaloids (1–7), including one new compound (1). Their structures were elucidated using NMR and HR-ESI-MS. The absolute configuration of 1 was established by ECD. A molecular docking and molecular dynamics simulation was carried out for the isolated compounds to screen for acetylcholine (AChE) inhibitory activity. The target compounds were evaluated for their inhibitory effects on AChE activity in vitro. The results suggest that these C. asiaticum alkaloids possess the ability to treat Alzheimer’s disease.

New essential oils (EOs) extracted from different parts of two Luvunga species (L. scandens and L. hongiaoensis) from Vietnam were investigated for their chemical composition, anti-inflammatory and cytotoxic activity. Sixty-nine total compounds were identified in the EOs by GC/MS. The major constituent of the leaf, fruit, and root EOs from L. scandens was β-caryophyllene (71.5%, 63.0%, and 31.5% respectively). The main compounds in L. hongiaoensis EOs were β-elemene (34.3% in leaf oil) and caryophyllene oxide (21.2% in root oil, 19.4% in stem oil). The EO from L. scandens fruits significantly inhibited nitric oxide production on LPS-induced RAW264.7 cells (IC50 = 37.95 ± 2.76 µg/mL). The EOs from L. hongiaoensis roots and L. scandens leaves and fruits exhibited cytotoxic activity against MCF-7, SK-LU-1, and HepG2 (IC50 from 49.74 ± 3.36 to 97.82 ± 8.61 µg/mL). This is the first report on L. hongiaoensis EOs and significantly complements the composition and bioactivity of L. scandens EOs.

Aplydactylonins A-C (1–3), three new sesquiterpenes, were isolated from the Vietnamese sea hare Aplysia dactylomela. Their structures and absolute configurations were elucidated based on spectroscopic analysis, X-ray crystallography, and density functional theory (DFT) calculations of NMR and ECD data. Compound 2 exhibited cytotoxicity against HepG2, DU145 and A549 cells with respective IC50 values of 4.08 ± 0.63, 38.64 ± 1.04 and 12.33 ± 0.95 µM. In addition, HepG2 cells treated with 5 μM compound 2 for 48 h showed a significant increase in early apoptotic cells (P

A phytochemical investigation of methanol extract from leaves of Pachyrhizus erosus (L.) Urban, a leguminous shrub distributed in Vietnam and other tropical and subtropical countries led to the isolation of a new prenylated chalcone, erosusone (1) and a new megastigmane glycoside epimer, 3-episedumoside F1 (9), together with thirteen known compounds including flavonoids (2-6), a 3-benzoxepine lactone (7), a pyridine-4,5-diol derivative (8), megastigmanes and megastigmane glycosides (10-15). Their structures were elucidated by means of high resolution-electrospray ionization (HR-ESI)-MS, one dimensional (1D) and two-dimensional NMR (2D-NMR) spectroscopy as well as comparison with the data reported in the literature. The cytotoxic effects on LU-1 (lung carcinoma), HepG2 (hepatocellular carcinoma), and MCF7 (breast carcinoma) cell lines were assessed. Prenylated chalcones 1-2 and isoflavone 3 exhibited cytotoxicity against all tested cell lines with IC50 values ranging from 22.04 to 45.03 µM.

Sixteen compounds (1-16) were isolated from Impatiens chapaensis. Chemical structures were determined by spectroscopic analyses and comparisons with previously published data. This report is the first to identify compounds 1, 5–7, 10, 12–14, and 16 from the genus Impatiens. Seven chosen isolates (5, 7, 10, 11, 12, 15, and 16) were submitted for α-glucosidase inhibition assays with acarbose as the positive control (IC50 = 227.14 ± 13.71 µM). Flavonoid 5 exhibited a significant inhibitory effect (IC50 = 101.00 ± 9.01 µM).

The first chemical study of the whole

Fluorescence imaging is an important technique used for early diagnosis and effective treatment of some incurable diseases including cancer. Herein, we report novel NaYF4:Yb3+/Er3+@silica-TPGS bio-nano complexes for labeling cancer cells. The NaYF4:Yb3+/Er3+ nanoparticles have been successfully synthesized via a hydrothermal route, further coated with a silica shell, and functionalized with d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). The experimental results indicate that NaYF4:Yb3+/Er3+@silica-TPGS emits stronger upconversion luminescence than NaYF4:Yb3+/Er3+ under an excitation of 980 nm. More significantly, the NaYF4:Yb3+/Er3+@silica-TPGS bio-nano complexes could strongly label MCF-7 breast cancer cells for in vitro experiments detected by a fluorescence microscope. On the other hand, the complex could not typically probe healthy cells, which are HEK-293A human embryonic kidney cells, under the same experimental conditions. Because of their strong upconversion luminescence, good dispersibility, and biocompatibility, NaYF4:Yb3+/Er3+@silica-TPGS bio-nano complexes can be a promising candidate/probe for biomedical labeling and diagnostics.

Prodigiosin (Pg) is a bright red pigment, which is produced by gram negative and gram positive bacteria including Serratia marcescens, Hahella chejuensis, Vibrio psychroerythrus, Streptomyces coelicolor and many other marine bacteria such as Pseudomonas sp., Vibrio sp. Pg induces apoptosis in different kinds of cancer cells with low toxicity on normal cells. In this study, we purified Pg from solid fermentation of S. marcescens M10 strain and assessed its anticancer activity in tumorized mice. The results showed that Pg was purified by running through a silicagel 60 column with a suitable solvent system of n-hexane:toluene at the rate of 1:1 (v/v) combined with toluene:ethyl acetate at the rate of 9:1 (v/v). TLC plate was used to test the presence of active substances with separation solvent n-hexane:ethyl acetate ratio of 1:1 (v/v). The purity of fractions tested by high performance liquid chromatography method showed as 98%. Purified fractions also showed promising anti-tumor activity in Lewis lung carcinoma induced tumors in BALB/c mice. The tumor volumes in Pg treated groups decreased by 34.18% after 28 days of administration.

Black pepper (Piper nigrum) is an autoicous and decorous vine cultivated in many local regions of Gia Lai. Black pepper is one of the most commonly consumed spices, and its pungency is due to the presence of alkaloids, such as piperine. This compound represents diverse biological activities, including anti-inflammatory, anticancer, antiviral, anti-larvicidal, pesticide, anti-alzheimer’s activities, etc. However, due to its poor solubility as well as its toxic effects at high use concentration, piperine is still in limit of pharmaceutical applications. In this study, we have used black pepper seed collected at Chu Se - Gia Lai to extract piperine. The compound extracted efficiency was approximately 18% with 96.7% of purity. Based on the obtained pure piperine, the hybrid nanopiperine-CD133 monoclonal antibody (mAb^CD133) complexes were fabricated with the nanoparticle size of about 170 nm, the polydispersity index (PDI) of 0.23 and the zeta potential of -9.4 mV. The nanocomplex was subjected for growth inhibitory activities against cancer colorectal cells (HT-29 cell line). The results showed that the nanopiperine-mAb^CD133 complex exhibited significant in vitro growth inhibition HT-29 colorectal cancer cells (46.56 ± 2.78%), while the viability of healthy cells remained unaffected (17.77 ± 0.82 %). The nanocomplex could also label 12.17% of HT-29 cells, which was rather higher than 3.83% from mAb^CD133 conjugated phycoerythrin (PE) as positive control. The fabricated nanopiperine-mAb^CD133 complex has proved the enhanced cytotoxic activities against colorectal cancerous cells as well as promising biopharmaceutical potency.