Fractionation, identification of chemical constituents, and biological properties of cashew (Anacardium occidentale L.) leaf extracts.

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.

Physiological responses and antioxidant properties of coriander plants (Coriandrum sativum L.) under different light intensities of red and blue lights.

Coriander (Coriandrum sativum L.) contains abundant antioxidants and essential oils which can provide antibacterial, antifungal, and antioxidant activities in the pharmaceutical, health and food production industry. To improve the economic values of coriander, the relationships between optimal light treatments for maximizing both plant growth and the antioxidant and essential oil content of coriander leaves need to be determined. Plants were exposed to five light-emitting diodes spectral color mixtures, high blue light (BL) intensity induced the levels of reducing power response. The light treatments were then adjusted for the analysis of secondary metabolite compounds of coriander leaves. Among 30 identified compounds, the amounts of decamethyl-cyclopentasiloxane and dodecane were significantly reduced in the R80 + G50 + B50 condition, whereas dodecamethyl-cyclohexasiloxane level was significantly reduced in R50 + G50 + B80 condition. Various light quality and intensity combinations influenced the accumulations of chlorophyll and phytochemical contents, mediated antioxidative properties, and secondary metabolites of coriander leaves, which may be useful in developing a new LED lighting apparatus optimized for coriander production in plant factories.

Bioactive Compounds, Antioxidants, and Health Benefits of Sweet Potato Leaves.

Sweet potato (Ipomoea batatas) is one of the most important food crops worldwide and its leaves provide a dietary source of nutrients and various bioactive compounds. These constituents of sweet potato leaves (SPL) vary among varieties and play important roles in treating and preventing various diseases. Recently, more attentions in health-promoting benefits have led to several in vitro and in vivo investigations, as well as the identification and quantification of bioactive compounds in SPL. Among them, many new compounds have been reported as the first identified compounds from SPL with their dominant bioactivities. This review summarizes the current knowledge of the bioactive compositions of SPL and their health benefits. Since SPL serve as a potential source of micronutrients and functional compounds, they can be further developed as a sustainable crop for food and medicinal industries.

Optimization of Ultrasound-Assisted Extraction of Flavonoids from Celastrus hindsii Leaves Using Response Surface Methodology and Evaluation of Their Antioxidant and Antitumor Activities.

Celastrus hindsii is a potential source of flavonoids with biological activities. This study aimed to develop an ultrasound-assisted technique for extracting flavonoids from leaves of C. hindsii. Response surface methodology was employed to optimize the extraction conditions for maximizing the total flavonoid content (TFC). A maximum TFC of 23.6 mg QE/g was obtained under the extraction conditions of ultrasonic power of 130 W, extraction temperature of 40°C, extraction time of 29 min, and ethanol concentration of 65%. The flavonoid-rich extracts were then studied for their antioxidant and anticancer activities. The results showed that the C. hindsii leaf extract exhibited potent radical scavenging activities against DPPH (IC50 of 164.85 µg/mL) and ABTS (IC50 of 89.05 µg/mL). The extract also significantly inhibited the growth of 3 cancer cell lines MCF7, A549, and HeLa with the IC50 values of 88.1 µg/mL, 120.4 µg/mL, and 118.4 µg/mL, respectively. Notably, the extract had no cytotoxicity effect on HK2 normal kidney cell line. This study suggests that flavonoid-rich extract is a promising antioxidant and anticancer agent and that ultrasound-assisted extraction is an efficient method for extracting flavonoids from C. hindsii leaves.

Liquid lipase-catalyzed hydrolysis of gac oil for fatty acid production: Optimization using response surface methodology.

Fatty acids are valuable products because they have wide industrial applications in the manufacture of detergents, cosmetics, food, and various biomedical applications. In enzyme-catalyzed hydrolysis, the use of immobilized lipase results in high production cost. To address this problem, Eversa Transform lipase, a new and low-cost liquid lipase formulation, was used for the first time in oil hydrolysis with gac oil as a triglyceride source in this study. Response surface methodology was employed to optimize the reaction conditions and establish a reliable mathematical model for predicting hydrolysis yield. A maximal yield of 94.16% was obtained at a water-to-oil molar ratio of 12.79:1, reaction temperature of 38.9 °C, enzyme loading of 13.88%, and reaction time of 8.41 h. Under this optimal reaction condition, Eversa Transform lipase could be reused for up to eight cycles without significant loss in enzyme activity. This study indicates that the use of liquid Eversa Transform lipase in enzyme-catalyzed oil hydrolysis could be a promising and cheap method of fatty acid production. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018.

Biochemical and Physiological Characteristics of Photosynthesis in Plants of Two Calathea Species.

Plants of the genus Calathea possess many leaf colors, and they are economically important because they are widely used as ornamentals for interior landscaping. Physiological performances and photosynthetic capacities of C. insignis and C. makoyana were investigated. The photosynthetic efficiencies of C. insignis and C. makoyana were significantly increased when the photosynthetic photon flux density (PPFD) increased from 0 to 600 µmol photons·m-2·s-1 and became saturated with a further increase in the PPFD. The two Calathea species had lower values of both the light saturation point and maximal photosynthetic rate, which indicated that they are shade plants. No significant differences in predawn Fv/Fm values (close to 0.8) were observed between dark-green (DG) and light-green (LG) leaf sectors in all tested leaves. However, the effective quantum yield of photosystem II largely decreased as the PPFD increased. An increase in the apparent photosynthetic electron transport rate was observed in both species to a maximum at 600 µmol·m-2·s-1 PPFD, following by a decrease to 1500 µmol·m-2·s-1 PPFD. Compared to LG leaf extracts, DG leaf extracts contained higher levels of chlorophyll (Chl) a, Chl b, Chls a + b, carotenoids (Cars), anthocyanins (Ants), flavonoids (Flas), and polyphenols (PPs) in all plants, except for the Ant, Fla and PP contents of C. insignis plants. Calathea insignis also contained significantly higher levels of total protein than did C. makoyana. The adjusted normalized difference vegetation index (NDVI), photochemical reflectance index (PRI), red-green, and flavonol index (FlavI) were significantly correlated to leaf Chls a + b, Cars, Ants, and Flas in C. makoyana, respectively, and can be used as indicators to characterize the physiology of these plants.