Sensomics-assisted analysis unravels the formation of the Fungus Aroma of Fu Brick Tea.

Fu Brick Tea (FBT) is characterized by Fungus Aroma (FA), which determines the quality of FBT products. However, the aroma constituents and their interactive mechanism for FA remain unclear. In this study, the FBT sample with the optimal FA characteristics was selected from 29 FBTs. Then, 19 components with OAV ≥ 1 were identified as the odorants involved in the FA formation. The aroma recombination test suggested that the FA was potentially produced by the synergistic interplay among the 15 key odorants, including (E,E)-2,4-heptadienal, (E,E)-2,4-nonadienal, (E)-2-nonenal, (E,Z)-2,6-nonadienal, (E)-2-octenal, (E)-ß-ionone, 4-ketoisophorone, dihydroactinidiolide, (E)-ß-damascenone, 1-octen-3-ol, linalool, geraniol, heptanal, hexanal, and phenylacetaldehyde. And, the synergistic effects between them were preliminarily studied by aroma omissions, such as modulatory effects, masking effects, compensatory effects, and novelty effects, ultimately contributing to the FA. In all, this work helps us better understand the formation of the FA and provides a basis for the improvement of FBT production technology.

Phytochemical composition of the diethyl ether extract of Artemisia lactiflora Wall. ex DC and its antimetastatic activity in human lung cancer cells.

Artemisia lactiflora Wall. ex DC. is a traditional Chinese medicinal plant used in the treatment of menstrual and hepatic disorders due to its antioxidant and anti-inflammatory properties. However, its anti-metastatic activity, which is the clinical challenge of lung cancer treatment, has not yet been reported. From the diethyl ether extract of Artemisia lactiflora, the four terpenoids, including dihydroactinidiolide, megastigmatrienone, alpha-curcumene, and dehydrovomifoliol, were the most intense peaks observed using LC-MS/MS, whereas bis (2-ethylhexyl) phthalate was a contaminant. In a transwell assay, the A. lactiflora diethyl ether extract (32 µg/ml) and dihydroactinidiolide (250 µg/ml) markedly inhibited the migration and invasion of non-small cell lung cancer (NSCLC) cells, similar to the standard anti-metastatic drug (capmatinib). Western blot analysis revealed that mesenchymal N-cadherin is downregulated in NSCLC cells under the treatment conditions. The potential anti-metastatic property of dihydroactinidiolide is promising as a new candidate anti-metastatic agent for lung cancer treatment.

Behavioral differences among domestic cats in the response to cat-attracting plants and their volatile compounds reveal a potential distinct mechanism of action for actinidine.

BACKGROUND: It has been known for centuries that cats respond euphorically to Nepeta cataria (catnip). Recently, we have shown that Lonicera tatarica (Tatarian honeysuckle), Actinidia polygama (silver vine), and Valeriana officinalis (valerian) can also elicit this "catnip response". The aim of this study was to learn if the behavior seen in response to these plants is similar to the response to catnip. Furthermore, we studied if these responses are fixed or if there are differences between cats. While nepetalactone was identified decades ago as the molecule responsible for the "catnip response", we know that this volatile is found almost exclusively in catnip. Therefore, we also aimed to identify other compounds in these alternative plants that can elicit the blissful behavior in cats. Bioassays with 6 cats were performed in a low-stress environment, where 5 plants and 13 single compounds were each tested for at least 100 and 17 h, respectively. All responses were video recorded and BORIS software was used to analyze the cats' behavior. RESULTS: Both response duration and behavior differed significantly between the cats. While individual cats had preferences for particular plants, the behavior of individual cats was consistent among all plants. About half a dozen lactones similar in structure to nepetalactone were able to elicit the "catnip response", as were the structurally more distinct molecules actinidine and dihydroactinidiolide. Most cats did not respond to actinidine, whereas those who did, responded longer to this volatile than any of the other secondary plant metabolites, and different behavior was observed. Interestingly, dihydroactinidiolide was also found in excretions and secretions of the red fox, making this the first report of a compound produced by a mammal that can elicit the "catnip response". A range of different cat-attracting compounds was detected by chemical analysis of plant materials but differences in cat behavior could not be directly related to differences in chemical composition of the plants. Together with results of, among others, habituation / dishabituation experiments, this indicates that additional cat-attracting compounds may be present in the plant materials that remain to be discovered. CONCLUSIONS: Collectively, these findings suggest that both the personality of the cat and genetic variation in the genes encoding olfactory receptors may play a role in how cats respond to cat-attracting plants. Furthermore, the data suggest a potential distinct mechanism of action for actinidine.

The identification of biotransformation pathways for removing fishy malodor from Bangia fusco-purpurea using fermentation with Saccharomyces cerevisiae.

The yeast Saccharomyces cerevisiae is effective in reducing the fishy malodor of sea products. However, the biotransformation pathways are still unclear. The seaweed B. fusco-purpurea was taken as an example to investigate the chemical transformation pathways for the deodorization process with S. cerevisiae fermentation. Sensory evaluation, GC-MS, GC-MS-O and odor activity value (OAV) analyses showed the fishy odorants were 1-octen-3-ol, (E)-2-nonenal, 2,4-decadienal, 2-pentylfuran, 2-octen-1-ol and nonanal. The removal of fishy malodor was related to the reactions of reduction, dehydrogenation, deformylation-oxygenation and ester syntheses via catalysis of aldehyde dehydrogenase, alcohol dehydrogenases, epoxide hydrolase, aldehyde deformylating-oxygenase, enone reductase, oxidases, dehydrogenases, aldo-keto reductases, ester synthase and acyltransferase. Interestingly, for the first time, it was found that 3,5-octadien-2-one transformed to 6-octen-2-one; and 2-pentylfuran transformed to o-cymene and hexyl acetate. Our findings enrich the knowledge for the removal of fishy malodor from sea products such as seaweeds.

Mitigation of oxidative stress with dihydroactinidiolide, a natural product against scopolamine-induced amnesia in Swiss albino mice.

The present work describes the neuroprotective efficacy of DHAc under escalated oxidative stress condition in scopolamine-induced amnesic mice. During the toxicity test of DHAc in mice, the acute dose (LD50) is found to be 3.468 mg/kg bw and the sub-acute dose is 0.68 mg/kg bw. Improved cognitive and learning abilities are observed in Morris water maze and Y-maze test in 10 days DHAc (0.68 mg/kg bw) treated scopolamine-induced male Swiss albino mice. In the molecular level these changes are monitored as reduced oxidative load followed by significantly lower lipid peroxidation and protein carbonylation, increased superoxide dismutase, catalase, acetylcholinesterase, caspase-3 activity and glutathione content followed by higher expression of anti apoptotic protein bcl-2 in mice brain as compared to scopolamine (1 mg/kg bw) treated mice. Meanwhile real time PCR shows higher expression of brain derived neurotrophic factor (BDNF) and synaptophysin in DHAc pretreated scopolamine treated mice brain. HPLC analysis suggested its possible blood brain barrier crossing ability. Overall DHAc reversed behavioral anomalies in the scopolamine treated mice via oxidative stress quenching, enhancing antioxidative enzyme activity, enhancing BDNF and synaptophysin mRNA levels and reducing expression of apoptotic protein Bax.

Dihydroactinidiolide regulates Nrf2/HO-1 expression and inhibits caspase-3/Bax pathway to protect SH-SY5Y human neuroblastoma cells from oxidative stress induced neuronal apoptosis.

Alzheimer's disease (AD) etiology has been studied for a long time and it is found to be multifaceted involving the accumulation of amyloid ß and tau protein. Oxidative stress is an early event in AD associated neurodegeneration provoking neuronal death through mitochondrial dysfunction and activation of caspase-3. Therefore we tested the efficacy of dihydroactinidiolide (DHAc), a monoterpene lactone against the oxidative load involved in AD like pathological conditions induced by sodium dithionite, glutamate, amyloid ß and colchicine in SH-SY5Y cells. Some of the indicators of neurotoxicity like acetylcholinesterase activity, intracellular reactive oxygen species (ROS), nitrite content, lipid peroxidation, protein carbonylation, nuclear and membrane damage were found to be significantly high in the toxicant treated cells when compared to the control cells while DHAc pretreatment significantly restored the toxicant induced neuronal damage signatures. Caspase-3 activity was found to be increased in the toxicant treated cells while DHAc significantly reduced it. Western blotting and RT-PCR revealed that DHAc significantly increased anti-apoptotic Bcl-2 expression and mRNA levels of Nrf2 and HO-1. Therefore DHAc was found to protect SH-SY5Y cells from neurotoxicant induced oxidative stress and apoptosis by regulating cellular antioxidant defenses and apoptosis related genes.

Understanding colour retention in red chilli pepper fruit using a metabolite profiling approach.

Carotenoids are the pigments responsible for conferring the characteristic deep red colour to chilli pepper. The post-harvest retention of this colour is a key trait that governs the price of the produce. Determining colour retention and the associated underlying biochemical mechanisms are important issues that require investigation. In this present study, the ability of image analysis to determine colour change in ground chilli fruit was evaluated. This method enabled differentiation of extreme retention phenotypes whilst also reducing the duration of storage required to make accurate determinations. The analysis of volatiles indicated different levels of lipid and carotenoid derived volatiles in lines with different retention properties. Metabolite profiling of intermediary metabolism supported these findings, with increased levels of unsaturated fatty acids present in lines with low retention properties. Collectively, these data have led us to propose that in chilli fruit lipid peroxidation is one of the progenitors of carotenoid degradation.

Enzymatic hydrolysis and auto-isomerization during ß-glucosidase treatment improve the aroma of instant white tea infusion.

The aroma changes in instant white tea resulting from ß-glucosidase treatment was investigated by quantitative descriptive analysis (QDA), gas chromatography-mass spectrometry (GC-MS), odour activity value analysis (OAV), aroma reconstruction and omission tests. The grassy, floral and sweet notes increased significantly (P < 0.05), and the roasted note decreased significantly (P < 0.05) upon ß-glucosidase treatment. Quantitative analysis showed that the concentrations of benzaldehyde, benzeneacetaldehyde, (Z)-3-hexen-1-ol, linalool, phenylethyl alcohol, cis-linalool oxide, trans-linalool oxide, hexanol, hotrienol and (E)-2-hexen-1-ol increased significantly (P < 0.05) after treatment; however, (Z)-3-hexen-1-ol isomerized to (E)-2-hexen-1-ol. OAV analysis, aroma reconstruction and the omission test showed that the grassy, floral and sweet notes increased as the (Z)-3-hexen-1-ol, cis/trans-linalool oxide and benzeneacetaldehyde increased, whereas the roasted note declined under the same conditions. The enzymatic hydrolysis of glycosidic precursors and the auto-isomerization of volatile compounds provide new information for understanding how ß-glucosidase treatment improves the aroma of tea products.

Dihydroactinidiolide, a natural product against Aß25-35 induced toxicity in Neuro2a cells: Synthesis, in silico and in vitro studies.

Synthesis of natural products has speeded up drug discovery process by minimizing the time for their purification from natural source. Several diseases like Alzheimer's disease (AD) demand exploring multi targeted drug candidates, and for the first time we report the multi AD target inhibitory potential of synthesized dihydroactinidiolide (DA). Though the activity of DA in several solvent extracts have been proved to possess free radical scavenging, anti bacterial and anti cancer activities, its neuroprotective efficacy has not been evidenced yet. Hence DA was successfully synthesized from ß-ionone using facile two-step oxidation method. It showed potent acetylcholinesterase (AChE) inhibition with half maximal inhibitory concentration (IC50) 34.03 nM, which was further supported by molecular docking results showing strong H bonding with some of the active site residues such as GLY117, GLY119 and SER200 of AChE. Further it displayed DPPH and (.NO) scavenging activity with IC50 value 50 nM and metal chelating activity with IC50 >270 nM. Besides, it significantly prevented amyloid ß25-35 self-aggregation and promoted its disaggregation at 270 nM. It did not show cytotoxic effect towards Neuro2a (N2a) cells up to 24 h at 50 and 270 nM while it significantly increased viability of amyloid ß25-35 treated N2a cells through ROS generation at both the concentrations. Cytotoxicity profile of DA against human PBMC was quite impressive. Hemolysis studies also revealed very low hemolysis i.e. minimum 2.35 to maximum 5.61%. It also had suitable ADME properties which proved its druglikeness. The current findings demand for further in vitro and in vivo studies to develop DA as a multi target lead against AD.

Chemical constituents from leaves of Uncaria rhynchophylla / 中草药

Objective: To study the chemical constituents from the leaves of Uncaria rhynchophylla and their antioxidant activities. Methods: The compounds were isolated by various column chromatography. Their structures were identified by spectroscopic methods including 1H-NMR, 13C-NMR, MS, HR-MS, etc. The antioxidant activities were evaluated by DPPH radical scavenging assay. Results: Seventeen compounds were isolated from the leaves of U. rhynchophylla, and identified as 18, 19-hydroxy- vincosamide (1), α-tocopherol (2), α-tocospiro A (3), dihydroactinidiolide (4), ursolic acid lactone (5), 3, 4-dehydrotheaspirone (6), chakyunglupulin A (7), ursolic acid (8), protocatechuic acid (9), quercetin (10), epicatechin (11), chlorogenic acid ethyl ester (12), quercetin-3-O-robinobioside (13), rutin (14), methyl caffeate (15), strictosamide (16), and vincosamide (17). The anti-oxidative IC50 values of compounds 10, 11, and 13-15 were 7.52, 8.21, 8.14, 2.13, and 5.35 μmol/L, respectively, which were better than the positive control Vit E (IC50 value was 9.53 μmol/L). Conclusion: Compound 1 is a new compound named as vincosamide A, and compounds 2-7, 9, 12, 13, and 15 are isolated from genus Uncaria Schreber nom. cons. for the first time. Moreover, compounds 10, 11, and 13-15 have the certain prospects in the development of natural anti-oxidative agents.

Chemical constituents from aerial parts of Ligusticum sinense cv. chaxiong / 中草药

Objective: To study the chemical constituents from the aerial parts of Ligusticum sinense cv. chaxiong. Methods: The chemical constituents were separated and purified by silica gel, ODS column chromatography, and preparative HPLC. Their structures were determined by various of spectroscopic analyses. Results: Fourteen compounds were isolated from the petrol ester and CH2Cl2 fractions of 95% ethanol extract of the aerial parts of L. sinense cv. chaxiong, and their structures were identified as 5-hydroxy-3- butylphthalide (1), 3-hydroxy-octa-1, 5-dien-7-one (2), umbelliferone (3), pumbinernoid A (4), crocinervolide (5), (3R, 6R, 7E)-3- hydroxy-4, 7-megastignadien-9-one (6), senkyunolide G (7), scopoletin (8), (2Z)-3-(3, 4-dihydroxyphenyl)-2-propenal (9), (3S, 5R, 6S, 7E, 9R)-5, 6-epoxy-3, 9-dihydroxy-7-megastigmene (10), vomifoliol (11), dihydroactinidiolide (12), 7-hydroxy-3-butylphthalide (13), and senkyunolide A (14). Conclusion: Compounds 1-13 are isolated from this plant for the first time, compounds 1, 2, 4-6, and 9-13 are found from the plants of genus Ligusticum L. for the first time, and compound 1 is a new natural product.