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Novel natural products (NPs) and their derivatives are important sources for drug discovery, which have been broadly applied in the fields of agriculture, livestock, and medicine, making the synthesis of NPs and their derivatives necessarily important. In recent years, biosynthesis technology has received increasing attention due to its high efficiency in the synthesis of high value-added novel products and its advantages of green, environmental protection, and controllability. In this review, the technological advances of biosynthesis strategies in the discovery of novel NPs and their derivatives are outlined, with an emphasis on two areas of host engineering and in vitro enzymatic synthesis. In terms of hosts engineering, multiple microorganisms, including Streptomyces, Aspergillus, and Penicillium, have been used as the biosynthetic gene clusters (BGCs) provider and host strain for the expression of BGCs to discover new compounds over the past years. In addition, the use of in vitro enzymatic synthesis strategy to generate novel compounds such as triterpenoid saponins and flavonoids is also hereby described. [ABSTRACT FROM AUTHOR]

Plants make different defense mechanisms in response to different environmental stresses. One common way is to produce secondary metabolites. Temperature is the main environmental factor that regulates plant secondary metabolites, especially flavonoids and terpenoids. Stress caused by temperature decreasing to 4–10 °C is conducive to the accumulation of flavonoids and terpenoids. However, the accumulation mechanism under cold stress still lacks a systematic explanation. In this review, we summarize three aspects of cold stress promoting the accumulation of flavonoids and terpenoids in plants, that is, by affecting (1) the content of endogenous plant hormones, especially jasmonic acid and abscisic acid; (2) the expression level and activity of important transcription factors, such as bHLH and MYB families. This aspect also includes post-translational modification of transcription factors caused by cold stress; (3) key enzyme genes expression and activity in the biosynthesis pathway, in addition, the rate-limiting enzyme and glycosyltransferases genes are responsive to cold stress. The systematic understanding of cold stress regulates flavonoids, and terpenoids will contribute to the future research of genetic engineering breeding, metabolism regulation, glycosyltransferases mining, and plant synthetic biology. [ABSTRACT FROM AUTHOR]

Fungi, organisms of high nutritional value with significant bioactive compound content, are considered to be nutraceuticals, mycotherapeutics, cosmeceuticals and useful for the production of functional foods. Their cultivation allows the sustainable management of agro-industrial wastes and generates good income with low inputs, constituting a good opportunity for the development of economically depressed rural areas. There are also many possible uses for the spent substrate in various sectors. provide an overview of the nutritional value of mushrooms and the cultivation of edible and medicinal mushrooms cultivation and uses in Italy. [ABSTRACT FROM AUTHOR]

Soil–rock mixtures is a special engineering geological material and often used as a roadbed filler. Based on the orthogonal experimental method, a series of large-scale triaxial tests of soil–rock mixtures under the freeze–thaw cycle environment was designed with five factors including rock content, compaction degree, moisture content, number of freeze–thaw cycles and freezing temperature at four experimental levels, respectively. Then, the effect of each orthogonal experimental factor and the effect of the confining pressure on the statics mechanical characteristics of the soil–rock mixtures were statistically investigated by range and variance analysis. Research results showed that the static stress of the soil–rock mixtures is linearly positively correlated with the confining pressure; for different confining pressures, the most crucial factors to affect the static stress are different; for the shear strength, the most crucial factors to affect the cohesive force and friction angle are correspondingly number of freeze–thaw cycles and rock content. The study of the crucial influence factors at different confining pressures after freeze–thaw cycles can provide guidance for design and protection of soil–rock mixtures under different environment. [ABSTRACT FROM AUTHOR]

Triterpenoid saponins are structurally diverse secondary metabolites. They are the main active ingredient of many medicinal plants and have a wide range of pharmacological effects. Traditional production of triterpenoid saponins, directly extracted from cultivated plants, cannot meet the rapidly growing demand of pharmaceutical industry. Microorganisms with triterpenoid saponins production ability (especially Agrobacterium genus) and biotransformation ability, such as fungal species in Armillaria and Aspergillus genera and bacterial species in Bacillus and Intestinal microflora, represent a valuable source of active metabolites. With the development of synthetic biology, engineering microorganisms acquired more potential in terms of triterpenoid saponins production. This review focusses on potential mechanisms and the high yield strategies of microorganisms with inherent production or biotransformation ability of triterpenoid saponins. Advances in the engineering of microorganisms, such as Saccharomyces cerevisiae, Yarrowia lipolytica, and Escherichia coli, for the biosynthesis triterpenoid saponins de novo have also been reported. Strategies to increase the yield of triterpenoid saponins in engineering microorganisms are summarized following four aspects, that is, introduction of high efficient gene, optimization of enzyme activity, enhancement of metabolic flux to target compounds, and optimization of fermentation conditions. Furthermore, the challenges and future directions for improving the yield of triterpenoid saponins biosynthesis in engineering microorganisms are discussed. [ABSTRACT FROM AUTHOR]

Dioscorea oppositifolia (Chinese yam) (DO) and Dioscorea hamiltonii (DH) are the plants of the genus Dioscorea and they are used as health food and traditional Chinese medicine. In order to development of the available DO and DH source, a comparative study of principal components and activities were carried on. DO and DH was qualitatively and quantitively profiled, and we comparatively evaluated their antioxidant (reducing power assay), anti-inflammatory (xylene-induced ear oedema test) and nonspecific immune regulating (carbon clearance test) activities. The 42 and 38 compounds were detected from DO and DH by the method UPLC-DAD-Q-TOF-MS/MS, respectively, as well as 14 compounds are quantified by HPLC and the methodology was examined. This is the first study of the composition and activities of DH, it also indicates that DO and DH consumption would be beneficial to the health. They may be useful in the production of functional food containing an efficacious dose. [ABSTRACT FROM AUTHOR]

Context: Aquilariae Lignum Resinatum (ALR), the dry rhizome of Aquilaria agallocha R. (Thymelaeaeeae), has been widely used to treat emesis, stomachache and gastrointestinal dysfunction. Objective: This study evaluates the effects of ALR methanol extract on gastrointestinal motility (GIM) and possible mechanisms of the action involved. Materials and methods: In vivo, the study evaluated the effects of ALR (200-800 mg/kg) on gastric emptying and small intestinal motility in normal and neostigmine-induced adult KM mice. The in vitro effects of ALR (0.2-1.6 mg/mL) on GIM were performed on isolated jejunum of Wistar rats, pretreated with acetylcholine (ACh), KCl, CaCl2, and pre-incubation with L-NAME (a selective inhibitor of the nitric oxide synthase). Results: In vivo, ALR (800 mg/kg) decreased gastric emptying (70.82 ± 9.81%, p < 0.01, compared with neostigmine group 91.40 ± 7.81%), small intestinal transit (42.82 ± 3.82%, p < 0.01, compared with neostigmine group 85.53 ± 5.57%). In vitro, ALR concentration dependently decreased the contractions induced by ACh (10−5 M) and KCl (60 mM) with respective EC50 values of 0.35 and 0.32 mg/mL. The Ca2+ concentration-response curves were shifted by ALR to the right, similar to that caused by verapamil (the positive). The spasmolytic activity of ALR was inhibited by pre-incubation with L-NAME. Discussion and conclusions: ALR played a spasmolytic role in GIM, which is probably mediated through inhibition of muscarinic receptors, blockade of Ca2+ influx and NO release. This is the first study presenting a comprehensive description of the effects of ALR on GIM. [ABSTRACT FROM AUTHOR]

Eleven compounds were isolated from the rhizomes of Paris polyphylla Smith var. yunnanensis. Their structures were elucidated on the basis of rigorous 1D and 2D NMR experiments as well as comparison with the literature data. To the best of our knowledge, compound 1 was only predicted by UPLC/Q-TOF MSE and the NMR spectroscopic data was given for the first time. The cytotoxic activities of all compounds on mouse B16 cells were evaluated. Among the tested molecules, compounds 6–9 showed strong cytotoxicities, while compound 1 did not show significant effect. [ABSTRACT FROM AUTHOR]

Ferulic acid (FA) acts as a powerful antioxidant against various age-related diseases. To investigate the effect and underlying mechanism of FA against d-galactose(d-gal)-induced memory deficit, mice were injected with d-gal to induce memory impairment and simultaneously treated with FA and donepezil. The behavioral results revealed that chronic FA treatment reversed d-gal-induced memory impairment. Further, FA treatment inhibited d-gal-induced AChE activity and oxidative stress via increase of superoxide dismutase activity and reduced glutathione content, as well as decrease of malondialdehyde and nitric oxide levels. We also observed that FA significantly inhibits inflammation in the brain through reduction of NF-κB and IL-1β by enzyme-linked immunosorbent assay. Additionally, FA treatment significantly reduces the caspase-3 level in the hippocampus of d-gal-treated mice. Hematoxylin and eosin and Nissl staining showed that FA prevents neurodegeneration induced by d-gal. These findings showed that FA inhibits d-gal-induced AChE activity, oxidative stress, neuroinflammation and neurodegeneration, and consequently ameliorates memory impairment. [ABSTRACT FROM AUTHOR]

Context:Folium Eriobotryae(FE), the dry leaf ofEriobotrya japonica(Thunb.) Lindl. (Rosaceae), has been widely used to treat respiratory disorders. Objective:To examine the bronchodilatory activity of FE and the potential mechanisms involved. Materials and methods:The effects of ethyl acetate fraction of FE (EFE) (0.05–0.3 mg/mL) on the isolated tracheal strips, and ursolic acid (UA) (5–30 μg/mL) that was the main constituent of EFE, were testedin vitro. Meanwhile, acetylcholine (Ach) and histamine (His)-induced bronchospasm were conductedin vivoin guinea pig. Furthermore, mechanisms of relaxant effects of EFE and UA were evaluated in the absence and presence of specific inhibitors. Results:Within vitrostudies, the contractile response evoked by Ach or His (EC50 = 0.21 and 0.16 mg/mL) was decreased by EFE, and UA caused a concentration-dependent relaxation precontracted by His (EC50 = 23.2 μg/mL). Within vivostudies, EFE strongly prolonged preconvulsive time similar to isoprenalin. The bronchodilator effects of EFE could be blocked by propranolol (1 μM),NG-nitro-l-arginine methyl ester (l-NAME) (100 μM) and 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one (ODQ) (1 μM). EFE also inhibited the contraction in Ca2+-free medium and produced rightward parallel displacement of CaCl2curves. In addition, the relaxant effects of UA could only be blocked byl-NAME and ODQ. Discussion and conclusion:These results suggest that bronchodilator activities of EFE were related to activation of β-adrenoceptor and NO/cGMP pathway. Blockage of Ca2+ channels and inhibition of IP3R-mediated internal Ca2+ release were also involved. Additionally, UA produced relaxant effects by the NO/cGMP pathway. [ABSTRACT FROM AUTHOR]

The chemometric approach was used to study the relationship between chemical compositions and antioxidative activity ofZiziphus jujubaMill. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging activity and reducing power were investigated, and the contents of total phenolics, flavonoids, anthocyanins, saponins, sugars, cAMP, and cGMP were also measured. Significant differences were found in 20 varieties of Chinese jujube. By principal component analysis, the highest chemical contents were exhibited byZiziphus jujubacv. Shandongchangzao. Simple correlation and partial correlation analysis indicated that total flavonoids and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity showed significant correlation; total phenolics and reducing power showed significant correlation (p < 0.05). [ABSTRACT FROM AUTHOR]

Context: Radix Aucklandiae, the dry rhizome of Aucklandia lappa Decne (Asteraceae), enjoyed traditional popularity for its antidiarrheal effects. Although there are many investigations on its chemical constituents and pharmacologic actions, few studies explaining its activity and mechanism in gastrointestinal disorders are available. Objective: In this paper, we focused on the effects of the methanol extract of R. Aucklandiae (RA ext) on gastrointestinal tract, so as to assess some of the possible mechanisms involved in the clinical treatment. Materials and methods: In vivo, in neostigmine-induced mice and normal mice, after intragastric administration, RA ext (100, 200, 300, and 400 mg/kg) was studied on gastrointestinal transit including gastric emptying and small intestinal motility. Meanwhile, in vitro, the effect of it (0.1, 0.2, 0.3, and 0.4 mg/mL) on the isolated tissue preparations of rat jejunum was also investigated , as well as costunolide and dehydrocostuslactone which were the main constituents. Results: In vivo, the gastric emptying increased and intestinal transit decreased after the administration of RA ext in normal mice. However, RA ext inhibited the gastric emptying and the intestinal transit throughout the concentrations in neostigmine-induced mice. In vitro, RA ext caused inhibitory effect on the spontaneous contraction of rat-isolated jejunum in a dose-dependent manner ranging from 0.1 to 0.4 mg/mL, and it also relaxed the acetylcholine chloride (Ach, 10−5 M), 5-hydroxytryptamine (5-HT, 200 μM)-induced, and K+ (60 mM)-induced contractions. RA ext shifted the Ca2+ concentration-response curves to right, similar to that caused by verapamil (0.025 mM). The Ca2+ concentration-response curves were shifted by costunolide (CO) (5.4, 8.1, and 10.8 μg/mL), dehydrocostuslactone (DE) (4.6, 6.9, and 9.2 μg/mL), costunolide-dehydrocostuslactone (CO-DE) (5.4-4.6, 8.1-6.9, and 10.8-9.2 μg/mL) to the right, similar to that caused by verapamil (0.01 mM). Discussion and conclusion: These results indicate that RA ext played a spasmolytic role in gastrointestinal motility, which is probably mediated through the inhibition of muscarinic receptors, 5-HT receptors, and calcium influx. The presence of cholinergic and calcium antagonist constituents may be the compatibility of CO and DE. All these results provide a pharmacological basis for its clinical use in the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Context. Paris bashanensis Wang et Tang (Liliaceae) is widely used in traditional Chinese medicine for the treatment of injuries, fractures and hemorrhage in Hubei and Sichuan Province. Objective: The n-BuOH extract of Paris bashanensis was investigated for hemostatic activity and chemical constituents in order to provide a basis for the application in folk use. Materials and methods: The n-BuOH extract of P. bashanensis was divided into three eluents (30, 50 and 70% EtOH) by macroporous adsorptive resin D101. The bleeding time of breaking tail hemostasis and clotting time of capillary and slide method in mice were used extensively to screen the hemostasis properties after repetitive administration of these three fractions (100 mg/kg, 50 mg/kg) for 5 days (total of 5 times, once per day). The chemical compounds were analyzed by HPLC-UV. Results: The inhibition rates in the bleeding time of 70, 50 and 30% n-BuOH ext. were 45, 32 and 21%, respectively. Using the slide method the decreasing rate of the clotting time of 70, 50 and 30% n-BuOH ext. were 71, 65 and 32% and in the experiment of capillary method, the inhibition rates were 43, 31 and 24%, respectively. A total of 70% n-BuOH ext. showed a high content of the pennogenin-type saponins by HPLC-UV. Discussion and conclusions: The 70% n-BuOH ext. of P. bashanensis was found to contain high levels of pennogenin saponins , which may lead to a higher hemostatic activity. Combined with the hemostatic test, P. bashanensis could be used as a resource of hemostatic drug. [ABSTRACT FROM AUTHOR]

Context: Saponins are active compounds in natural products. Many researchers have tried to find the method for knowing their concentration in herbs. Some methods, such as solid-liquid extraction and solvent extraction, have been developed. However, the extraction methods of the steroidal saponins from Paris polyphylla Smith var. yunnanensis (Liliaceae) are not fully researched. Objective: To establish a simple extraction method for the separation of steroidal saponins from the rhizomes of P. polyphylla Smith var. yunnanensis. Materials and methods: Macroporous adsorption resins were used for the separation of steroidal saponins. To select the most suitable resins, seven kinds of macroporous resins were selected in this study. The static adsorption and desorption tests on macroporous resins were determined. Also, we optimized the temperature and the ethanol concentration in the extraction method by the contents of five kinds of saponins. Then, we compared the extraction method with two other methods. Results: D101 resin demonstrated the best adsorption and desorption properties for steroidal saponins. Its adsorption data fits best to the Freundlich adsorption model. The contents of steroidal saponins in the product were 4.83-fold increased with recovery yields of 85.47%. Discussion and conclusion: The process achieved simple and effective enrichment and separation for steroidal saponins. The method provides a scientific basis for large-scale preparation of steroidal saponins from the Rhizoma Paridis and other plants. [ABSTRACT FROM AUTHOR]

Context: Currently, famous traditional Chinese medicine formulas have undergone re-evaluation and development in China. Wei-Chang-An-Wan (WCAW) as one of them has been used for treating various gastrointestinal diseases for several decades. The secondary development of WCAW is in progress so as to interpret the effective material basis or find new pharmacological activity. Objective: To evaluate the antinociceptive effect of methanol extract of WCAW (ME) as well as four fractions (P.E., EtOAc, n-BuOH, H2O) and obtain information on the correlation between the contents of the fractions and antinociceptive effect. Materials and methods: ME was divided into four parts extracted by petroleum ether, ethyl acetate and n-butanol. Antinociceptive activity was evaluated by three models of acetic acid-induced writhing, formalin and hot-plate test in mice after repetitive administration of ME at 200, 400 or 800 mg/kg, P.E. 132 mg/kg, EtOAc 106 mg/kg, n-BuOH 176 mg/kg and H2O 176 mg/kg for six days. The chemical compounds were analyzed by HPLC-ESI-MS. Results: ME at 800 mg/kg inhibited acid-induced writhing by 84.69%, and reduced the licking time of second phase in formalin test by 53.23%. The inhibition rates in acid-induced writhing of P.E., EtOAc, n-BuOH and H2O were 27.79, 33.85, 38.97 and 37.69%, respectively, and in formalin test about 50%. They had no effect on the hot-plate test. HPLC-ESI-MS analysis showed that 68 chemical compounds were detected and 41 compounds were identified from ME. Discussion and conclusion: The results obtained herein indicate that WCAW possesses the antinociceptive activity that provides a new aspect in clinical application. [ABSTRACT FROM AUTHOR]

Conclusion. The results obtained in this study indicate that NG-nitro-L-arginine methyl ester (L-NAME) protects cochlear damage from acoustic trauma through reducing the production of nitric oxide (NO). Objectives. This study aimed to explore whether NO synthase inhibitor L-NAME could reduce cochlear damage in acoustic trauma. Materials and methods. Seventy guinea pigs (300-350g) were divided randomly into four groups (n=20 in groups I, III, and IV; n=10 in group II). Two days consecutively and 30min before noise exposure (4kHz octave band, 115dB SPL 5h), subjects received an injection of 5ml saline/kg (groups I and III) or 10mg/kg L-NAME (groups II and IV). Sham-exposed guinea pigs were listed as groups I and II. Protection was assessed physiologically by the change in auditory brainstem response (ABR) threshold and histologically by survival of outer hair cells (OHCs). NO level of cochlear tissue was assayed 3days after noise exposure. Results. Group III showed significantly greater OHC loss, threshold shifts and NO level compared with group I and group IV. Compared with group III, noise-induced elevation in NO level in the cochlea was significantly attenuated by L-NAME (p<0.001). [ABSTRACT FROM AUTHOR]

Abstract Natural products of plant origin are of high interest and widely used, especially in the food industry, due to their low toxicity and wide range of bioactive properties. Compared to other plant components, the safety of polysaccharides has been generally recognized. As dietary fibers, plant-derived polysaccharides are mostly degraded in the intestine by polysaccharide-degrading enzymes secreted by gut microbiota, and have potential prebiotic activity in both non-disease and disease states, which should not be overlooked, especially in terms of their involvement in the treatment of intestinal diseases and the promotion of intestinal health. This review elucidates the regulatory effects of plant-derived polysaccharides on gut microbiota and summarizes the mechanisms involved in targeting gut microbiota for the treatment of intestinal diseases. Further, the structure-activity relationships between different structural types of plant-derived polysaccharides and the occurrence of their prebiotic activity are further explored. Finally, the practical applications of plant-derived polysaccharides in food production and food packaging are summarized and discussed, providing important references for expanding the application of plant-derived polysaccharides in the food industry or developing functional dietary supplements. [ABSTRACT FROM AUTHOR]