RESUMO
The Korean mountains are home to the Korean red pine (Pinus densiflora). Pine needle oil has been used as a food additive and a traditional herbal medicine; however, any health-related properties of its trunk oil remain unknown. Herein, we assessed antibacterial and antiviral properties of essential oil extracted from the trunk of P. densiflora. Th extracted oil was hydrodistilled using a Clevenger apparatus and analyzed using gas chromatography-mass spectrometry. The antimicrobial activity of the oil was tested using the microbroth dilution technique against 10 bacterial species (6 g-positive and 4 g-negative) and fungi. The extract exerted strong antimicrobial activity against Vibrio parahaemolyticus, Bacillus cereus, Listeria monocytogenes, Propionibacterium acnes, and Malassezia furfur (minimum inhibitory concentration = 10 mL/L). Additionally, it exhibited dose-dependent activity against influenza virus A and feline coronavirus. Furthermore, among 20 identified constituents accounting for 98.7% of the oil contents, the major components included 3-cyclohexene-1-methanol (10.12%), 2-(4-methylcyclohexyl)-2-propanol (9.09%), fenchone (8.14%), O-isopropyltoluene (6.35%), and isothymol methyl ether (6.14%). The P. densiflora trunk essential oil showed antibacterial and antiviral activities that depended on its chemical composition and the microbial strains tested herein. The essential oil can be used as an antimicrobial agent and disinfectant.
RESUMO
Platycosides, saponins contained in balloon flower, which have been used as food health supplements for respiratory diseases, have diverse pharmacological effects. Platycosides exhibit better pharmacological activity by hydrolyzing their own sugars. However, to date, there have been no studies on the production of deglucosylated platycodin D suitable for food applications. In this study, Pluszyme 2000P, which was derived from Aspergillus niger, a food-grade microorganism, was used to completely convert platycoside E into deglucosylated platycodin D. For an efficient and economical production of deglucosylated platycodin D, the productivity was improved approximately 2.4 times by application of high hydrostatic pressure and the discarded balloon flower leaf was used as a substrate. As a result, deglucosylated platycodin D was produced with the highest concentration (3.49 mg/mL) and productivity (581.7 mg/L/h) reported so far. Our results contribute to functional saponin production and the related food industries.
RESUMO
Petasites japonicus have been used since a long time in folk medicine to treat diseases including plague, pestilential fever, allergy, and inflammation in East Asia and European countries. Bioactive compounds that may prevent and treat infectious diseases are identified based on their ability to inhibit bacterial neuraminidase (NA). We aimed to isolate and identify bioactive compounds from leaves and stems of P. japonicas (PJA) and elucidate their mechanisms of NA inhibition. Key bioactive compounds of PJA responsible for NA inhibition were isolated using column chromatography, their chemical structures revealed using 1 H NMR, 13 C NMR, DEPT, and HMBC, and identified to be bakkenolide B (1), bakkenolide D (2), 1,5-di-O-caffeoylquinic acid (3), and 5-O-caffeoylquinic acid (4). Of these, 3 exhibited the most potent NA inhibitory activity (IC50 = 2.3 ± 0.4 µM). Enzyme kinetic studies revealed that 3 and 4 were competitive inhibitors, whereas 2 exhibited non-competitive inhibition. Furthermore, a molecular docking simulation revealed the binding affinity of these compounds to NA and their mechanism of inhibition. Negative-binding energies indicated high proximity of these compounds to the active site and allosteric sites of NA. Therefore, PJA has the potential to be further developed as an antibacterial agent for use against diseases associated with NA.
Assuntos
Clostridium perfringens/enzimologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Neuraminidase/antagonistas & inibidores , Petasites/química , Extratos Vegetais/farmacologia , Ácido Quínico/análogos & derivados , Sesquiterpenos/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Cinética , Estrutura Molecular , Neuraminidase/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ácido Quínico/química , Ácido Quínico/isolamento & purificação , Ácido Quínico/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificaçãoRESUMO
OBJECTIVES: To optimize conversion of rutin to isoquercetin by commercial α-L-rhamnosidase using high hydrostatic pressure (HHP). RESULTS: The de-rhamnosylation activity of α-L-rhamnosidase for isoquercetin production was maximal at pH 6.0 and 50 °C using HHP (150 MPa). The enzyme showed high specificity for rutin. The specific activity for rutin at HHP was 1.5-fold higher than that at atmospheric pressure. The enzyme completely hydrolysed 20 mM rutin in tartary buckwheat extract after 2 h at HHP, with a productivity of 10 mM h(-1). The productivity and conversion were 2.2- and 1.5-fold higher at HHP than at atmospheric pressure, respectively. CONCLUSIONS: This is the first report concerning the enzymatic hydrolysis of isoquercetin in tartary buckwheat at HHP.
Assuntos
Fagopyrum/química , Glicosídeo Hidrolases/metabolismo , Quercetina/análogos & derivados , Rutina/química , Cromatografia Líquida de Alta Pressão , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise , Pressão Hidrostática , Quercetina/análise , Quercetina/isolamento & purificação , Sementes/químicaRESUMO
A recombinant enzyme from Lysinibacillus fusiformis was expressed, purified, and identified as an oleate hydratase because the hydration activity of the enzyme was the highest for oleic acid (with a k (cat) of 850 min(-1) and a K (m) of 540 µM), followed by palmitoleic acid, γ-linolenic acid, linoleic acid, myristoleic acid, and α-linolenic acid. The optimal reaction conditions for the enzymatic production of 10-hydroxystearic acid were pH 6.5, 35 °C, 4% (v/v) ethanol, 2,500 U ml(-1) (8.3 mg ml(-1)) of enzyme, and 40 g l(-1) oleic acid. Under these conditions, 40 g l(-1) (142 mM) oleic acid was converted into 40 g l(-1) (133 mM) 10-hydroxystearic acid for 150 min, with a molar yield of 94% and a productivity of 16 g l(-1) h(-1), and olive oil hydrolyzate containing 40 g l(-1) oleic acid was converted into 40 g l(-1) 10-hydroxystearic acid for 300 min, with a productivity of 8 g l(-1) h(-1).
Assuntos
Bacillaceae/enzimologia , Hidroliases/metabolismo , Ácido Oleico/metabolismo , Óleos de Plantas/metabolismo , Ácidos Esteáricos/metabolismo , Sequência de Bases , Clonagem Molecular , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Cromatografia Gasosa-Espectrometria de Massas , Hidroliases/química , Hidroliases/genética , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Peso Molecular , Azeite de Oliva , Reação em Cadeia da PolimeraseRESUMO
The optimal temperature and pH for retinal production using metabolically engineered Escherichia coli in a 7-l fermentor were found to be 30°C and 7.0, respectively. The agitation speed was a critical factor for retinal production. The optimal agitation speed was 400 rpm (oxygen transfer coefficient, k(L)a, = 92 1/h) in batch culture and 600 rpm (k(L)a=148 1/h) in a fed-batch culture of glycerol. Span 80 was selected as a surfactant for retinal production in metabolically engineered E. coli because Span 80 had proven the most effective for increased retinal production among the tested surfactants. Under the optimal conditions in the fed-batch culture with 5 g/l Span 80, the cell mass and the concentration, content, and productivity of retinal were 24.7 g/l, 600 mg/l, 24.3mg/g-cells, and 18 mg l(-1)h(-1) after 33 h, respectively. They were 1.2-, 2.7-, 2.3-, and 2.7-fold higher than those in the fed-batch culture without Span 80, respectively. The concentration and productivity of retinal in this study were the highest ever reported. The hydrophilic portion of Span 80 (sorbitan) did not affect cell growth and retinal production, but the hydrophobic portion (oleic acid) stimulated cell growth. However, oleic acid plus sorbitan did not stimulate retinal production. Thus, Span 80, as a linked compound of oleic acid and sorbitan produced by esterification, proved to be an effective surfactant for the enhancement of retinal production.
Assuntos
Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Hexoses/farmacologia , Microbiologia Industrial/métodos , Retinaldeído/biossíntese , Tensoativos/farmacologia , Técnicas de Cultura Celular por Lotes , Meios de Cultura , Glucose , Oxigênio , TemperaturaRESUMO
The immobilized endo- and exo-arabinanases from Caldicellulosiruptor saccharolyticus produced continuously an average of 16.5 gl(-1)l-arabinose from 20 gl(-1) sugar beet arabinan at pH 5.0 and 75°C for 216 h, with a productivity of 9.9 gl(-1)h(-1) and a conversion yield of 83%.
Assuntos
Arabinose/biossíntese , Beta vulgaris/química , Glicosídeo Hidrolases/metabolismo , Bactérias Gram-Positivas/enzimologia , Polissacarídeos/metabolismo , Reatores Biológicos , Enzimas Imobilizadas/metabolismo , Concentração de Íons de Hidrogênio , Cinética , TemperaturaRESUMO
In the fed-batch culture of glycerol using a metabolically engineered strain of Escherichia coli, supplementation with glucose as an auxiliary carbon source increased lycopene production due to a significant increase in cell mass, despite a reduction in specific lycopene content. L-Arabinose supplementation increased lycopene production due to increases in cell mass and specific lycopene content. Supplementation with both glucose and L-arabinose increased lycopene production significantly due to the synergistic effect of the two sugars. Cell growth by the consumption of carbon sources was related to endogenous metabolism in the host E. coli. Supplementation with L-arabinose stimulated only the mevalonate pathway for lycopene biosynthesis and supplementation with both glucose and L-arabinose stimulated synergistically only the mevalonate pathway. In the fed-batch culture of glycerol with 10 gl(-1) glucose and 7.5 gl(-1) L-arabinose, the cell mass, lycopene concentration, specific lycopene content, and lycopene productivity after 34 h were 42 gl(-1), 1,350 mgl(-1), 32 mg g cells(-1), and 40 mgl(-1)h(-1), respectively. These values were 3.9-, 7.1-, 1.9-, and 11.7-fold higher than those without the auxiliary carbon sources, respectively. This is the highest reported concentration and productivity of lycopene.