ABSTRACT
The current study aimed to identify the chemical constituents and bioactivities of the crude ethanolic extract (CEE) and its fractions (ethyl acetate (EAF), hexane (HEF), and aqueous (AEF)) from leaves of cashew (Anacardium occidentale L.) grown in Vietnam. A total of 31 compounds which belong to alkanes, hydrocarbons, iodine, terpenoids, phenolics, and flavonoids were determined by a gas chromatography-mass spectrometry (GC-MS) analysis, with bis(2-ethylhexyl) phthalate being the most prevailing compound. The highest total phenolic and flavonoid contents were obtained in the EAF, followed by HEF, CEE, and AQF. All samples showed promising in vitro antibacterial activity, enzyme inhibition, and anticancer activity. Among the samples tested, the EAF exhibited the highest enzyme inhibition activity against α-amylase and α-glucosidase (IC50 values of 51.24 µg/mL and 99.29 µg/mL, respectively), cytotoxicity activity against HeLa cells (IC50 value of 79.49 µg/mL), and antibacterial activity against Bacillus subtilis and Escherichia coli with MIC values of 5 mg/mL and 2.5 mg/mL, respectively. These findings suggest that the leaves of A. occidentale cultivated in Vietnam are a promising source of bioactive components and that EAF is a promising bioactive material warranting further pharmaceutical investigation.
ABSTRACT
Serevenia buxifolia is an evergreen citrus plant and has attracted considerable attention due to its bioactive components and biological activities. In the present study, the essential oil (EO) from S. buxifolia cultivated in Vietnam was demonstrated to exhibit the in vitro antioxidant, thrombolytic, anti-hemolysis, anti-inflammatory, and antidiabetic activities. Briefly, the gas chromatography coupled to mass spectrometry analysis revealed that the leaf EO of S. buxifolia was composed of 33 components, with the main constituents being ß-carypphyllene (32.5%), and elixene (9.8%). The extracted oil possessed a fairly high free radical scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH), with an IC50 value of 190.7 µg/mL compared with positive control, α-tocopherol, IC50 value of 42.6 µg/mL. The EO also exhibited thrombolytic activity: the percentage of inhibition was found to be 70.75% at 100 µL, in comparison with 87.2% for the positive control, streptokinase. For hemolytic activity, the percentage of inhibition of the EO was from 27.4% to 59.6% at concentrations from 10 to 100 µg/mL, respectively. The results of in vitro anti-inflammatory activity indicated that the EO of S. buxifolia leaves effectively protects the heat-induced denaturation, with an IC50 value of 40.25 µg/mL. The EO also exhibited antidiabetic potential, with IC50 values of 87.8 and 134.9 µg/mL against α-amylase and α-glucosidase, respectively. It is noteworthy that the potent biological activities of the obtained S. buxifolia oil increased in a dose-dependent manner. The results achieved show that the EO of S. buxifolia leaves can be a potential source for oxidative stress, inflammatory, and diabetic management.
ABSTRACT
Severinia buxifolia (Rutaceae) is often used as a traditional medical plant. The present study was carried out to estimate the effects of solvents (petroleum ether and hexane: ethyl acetate) used in liquid-liquid extraction to total terpenoid content (TTC) and in vitro anti-inflammatory activity of the extracts obtained from S. buxifolia bark. The results showed that solvent fractionation increased the TTC compared with crude extracts. The hexane: ethyl acetate bark extract fraction (HEF) had the highest TTC (731.48 µg/ml) in comparison with the petroleum ether bark extract fraction (PEF) (564.81 µg/ml) and the crude extract (CE) (184.26 µg/ml). In addition, one of composition of terpenoid of S. buxifolia, namely ursolic acid, was determined by HPLC method from the crude CE and the fractions PEF and HEF: 2.44 µg/g DW, 3.56 µg/g DW and 5.04 µg/g DW, respectively. The samples had an in vitro anti-inflammatory activity comparable with that of two reference standards (aspirin and indomethacin). Particularly, the HEF fraction had the highest in vitro anti-inflammatory activity (i.e., albumin denaturation: IC50 = 147.91 µg/mL, heat-induced hemolysis: IC50 = 159.91 µg/mL, proteinase inhibition: IC50 = 117.72 µg/mL, and lipoxygenase activity: IC50 = 90.45 µg/mL). Besides, the preliminary experiments of this study were conducted to determine the influences of maceration factors (solvent type, temperature, and time) for S. buxifolia bark extract. The TTC ranged from 453.70 to 842.59 mg linalool/g DW, and the extraction yield from 2.40% to 5.120% in all extracts. Based on TTC and EY, the hexane: acetone mixture is recommended as the optimal solvent to obtain the crude bark extract (CE) at 46°C for 24 hr of maceration. Extracts of S. buxifolia bark are a promising source for the treatment of inflammatory diseases.
ABSTRACT
OBJECTIVE: To evaluate the impact of plant growth regulators including kinetin (KN), benzyl adenine and naphthalene acetic acid, yeast extract and casein hydrolyzate on biomass accumulation of Vietnamese ginseng Panax vietnamensis (P. vietnamensis) in cell suspension culture. METHODS: Cell suspension cultures were established from friable calluses derived from leaves and petioles of 3-year-old in-vitro P. vietnamensis plants. The cell suspension cultures were grown in Murashige and Skoog basal media supplemented with various concentrations of KN, benzyl adenine, naphthalene acetic acid, and yeast extract and casein hydrolyzate. RESULTS: All tested factors generated an increase in the cell biomass of P. vietnamensis in suspension culture, but the impact of each varies depended on the factor type, concentration, and incubation period. Addition of 2.0 mg/L KN resulted in the largest biomass increase after 24 d, (57.0 ± 0.9) and (3.1 ± 0.1) mg/mL fresh and dry weight, respectively, whereas addition of benzyl adenine or naphthalene acetic acid produced optimum levels of Panax cell biomass at 1.0 and 1.5 mg/L, respectively. Addition of the elicitor yeast extract led to a 1.4-2.4 fold increase in biomass of P. vietnamensis, while addition of casein hydrolyzate enhanced biomass accumulation 1.8-2.6 fold. CONCLUSIONS: The addition of each factor causes significant changes in biomass accumulation of P. vietnamensis. The largest biomass accumulation is from cultures grown in MS media containing 2.0 mg/L KN for 24 d. The outcome of the present study provides new insights into the optimal suspension culture conditions for studies on the in vitro cell biomass production of P. vietnamensis.
ABSTRACT
The literature presents a growing body of evidence demonstrating the positive effect of probiotics on health. Probiotic consumption levels are rising quickly in the world despite the fluctuation of their viability and functionality. Technological methods aiming at improving probiotic characteristics are thus highly wanted. However, microbial metabolic engineering toolbox is not available for this kind of application. On the other hand, basic microbiology teaches us that bacteria are able to exhibit adaptation to external stresses. It is known that adequately applied sub-lethal stress, i.e., controlled in amplitude and frequency at a given stage of the culture, is able to enhance microbial robustness. This property could be potentially used to improve the viability of probiotic bacteria, but some technical challenges still need to be overcome before any industrial implementation. This review paper investigates the different technical tools that can be used in order to define the proper condition for improving viability of probiotic bacteria and their implementation at the industrial scale. Based on the example of Bifidobacterium bifidum, potentialities for simultaneously improving viability, but also functionality of probiotics will be described.
Subject(s)
Bacteria/metabolism , Metabolic Engineering , Probiotics , Adaptation, Biological , Bacteria/genetics , Environment , Fermentation , Food Microbiology , Microbial Viability , Quantitative Trait, Heritable , Stress, PhysiologicalABSTRACT
The effect of combined abiotic and biotic factors on plant volatile organic compound (VOC) emissions is poorly understood. This study evaluated the VOC emissions produced by Arabidopsis thaliana (L.) Col-0 subjected to 3 temperature regimes (17, 22, and 27°C) in the presence and absence of Plutella xylostella larvae over 2 time intervals (0-4 and 4-8 h), in comparison to control plants. The analyses of VOCs emitted by Arabidopsis plants were made by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS). It was found that certain volatile groups (e.g., alcohols, ketones, aldehydes, and terpenes) are induced by both single factors (temperature or larval infestation) and combined factors (temperature and larvae interactions), whereas other volatile groups (e.g., isothiocyanates [ITCs] and nitrile) were specific to the experimental conditions. ITCs (mainly 4-methylpentyl isothiocyanate) were emitted from plants subjected to larval infestation at 17 and 27°C after the 2 time intervals. The proportions of sulfides (mainly dimethyl disulfide) and 4-(methylthio) butanenitrile were significantly higher on herbivore-infested plants at 22°C compared to the other treatments. Overall, our findings indicate that changes in all experimental conditions caused significant changes to the VOC emissions of Arabidopsis plants. Therefore, the interaction between temperature and larval feeding may represent an important factor determining the variability of volatile emissions by plants subjected to multiple simultaneous factors.
