Non-Volatile Component and Antioxidant Activity: A Comparative Analysis between Litsea cubeba Branches and Leaves.

Litsea cubeba, which is found widely distributed across the Asian region, functions as both an economic tree and a medicinal plant with a rich historical background. Previous investigations into its chemical composition and biological activity have predominantly centered on volatile components, leaving the study of non-volatile components relatively unexplored. In this study, we employed UPLC-HRMS technology to analyze the non-volatile components of L. cubeba branches and leaves, which successfully resulted in identifying 72 constituents. Comparative analysis between branches and leaves unveiled alkaloids, organic acids, and flavonoids as the major components. However, noteworthy differences in the distribution of these components between branches and leaves were observed, with only eight shared constituents, indicating substantial chemical variations in different parts of L. cubeba. Particularly, 24 compounds were identified for the first time from this plant. The assessment of antioxidant activity using four methods (ABTS, DPPH, FRAP, and CUPRAC) demonstrated remarkable antioxidant capabilities in both branches and leaves, with slightly higher efficacy observed in branches. This suggests that L. cubeba may act as a potential natural antioxidant with applications in health and therapeutic interventions. In conclusion, the chemical composition and antioxidant activity of L. cubeba provides a scientific foundation for its development and utilization in medicine and health products, offering promising avenues for the rational exploitation of L. cubeba resources in the future.

A New Blend of Litsea cubeba, Pinus mugo, and Cymbopogon winterianus Essential Oil Active as an Anti-tyrosinase Ingredient in Topical Formulations.

Tyrosinase is a target enzyme to be inhibited in order to reduce excessive melanin production and prevent typical age-related skin disorders. Essential oils are complex mixtures of volatile compounds, belonging mainly to monoterpenoids and sesquiterpenoids, which have been relatively little studied as tyrosinase inhibitors. Among the monoterpenoids, citral (a mixture of neral and geranial) is a fragrance compound in several essential oils that has shown interesting tyrosinase inhibitory activity. Although citral is listed as an allergen among the 26 fragrances in Annex III of the Cosmetics Directive 2003/15/EC, it can be safely used for the formulation of topical products in amounts that are not expected to cause skin sensitization, as shown by various commercially available products.The aim of this work was to evaluate two different formulations (oil/water emulsion, oily solution) containing a new combination of essential oils (Litsea cubeba, Pinus mugo, Cymbopogon winterianus) applied to the skin both in nonocclusive and partially occlusive modes. The blend is designed to reduce the concentration of citral to avoid potential skin reactions while taking advantage of the inhibitory activity of citral. Specifically, the amount of citral and other bioactive compounds (myrcene, citronellal) delivered through the skin was studied as a function of formulation and mode of application.The results show that an oil/water emulsion is preferable because it releases the bioactive compounds rapidly and minimizes their evaporative loss. In addition, semi-occluded conditions are required to prevent evaporation, resulting in higher availability of the bioactive compounds in viable skin.

Inhaled Litsea glaucescens K. (Lauraceae) leaves' essential oil has anxiolytic and antidepressant-like activity in mice by BDNF pathway activation.

ETHNOPHARMACOLOGICAL RELEVANCE: Litsea glaucescens K. (Lauraceae) is a small tree from the Mexican and Central American temperate forests, named as "Laurel". Its aromatic leaves are ordinarily consumed as condiments, but also are important in Mexican Traditional Medicine, and among the most important non wood forest products in this area. The leaves are currently used in a decoction for the relief of sadness by the Mazahua ethnic group. Interestingly, "Laurel" has a long history. It was named as "Ehecapahtli" (wind medicine) in pre-Columbian times and applied to heal maladies correlated to the Central Nervous System, among them depression, according to botanical texts written in the American Continent almost five centuries ago. AIM OF THE STUDY: Depression is the first cause of incapacity in the world, and society demands alternative treatments, including aromatherapy. We have previously demonstrated the antidepressant-like activity of L. glaucescens leaves' essential oil (LEO), as well as their monoterpenes linalool, and beta-pinene by intraperitoneal route in a mice behavioral model. Here we now examined if LEO and linalool exhibit this property and anxiolytic activity when administered to mice by inhalation. We also investigated if these effects occur by BDNF pathway activation in the brain. MATERIALS AND METHODS: The LEO was prepared by distillation with water steam and analyzed by gas chromatography-mass spectrometry (GC-MS). The monoterpenes linalool, eucalyptol and ß-pinene were identified and quantified. Antidepressant type properties were determined with the Forced Swim Test (FST) on mice previously exposed to LEO or linalool in an inhalation chamber. The spontaneous locomotor activity and the sedative effect were assessed with the Open Field Test (OFT), and the Exploratory Cylinder (EC), respectively. The anxiolytic properties were investigated with the Elevated Plus Maze Apparatus (EPM) and the Hole Board Test (HBT). All experiments were video documented. The mice were subjected to euthanasia, and the brain hippocampus and prefrontal cortex were dissected. RESULTS: The L. glaucescens essential oil (LEO) contains 31 compounds according to GC/MS, including eucalyptol, linalool and beta-pinene. The LEO has anxiolytic effect by inhalation in mice, as well as linalool, and ß-pinene, as indicated by OFT and EC tests. The LEO and imipramine have antidepressant like activity in mice as revealed by the FST; however, linalool and ketamine treatments didn't modify the time of immobility. The BDNF was increased in FST in mice treated with LEO in both areas of the brain as revealed by Western blot; but did not decrease the level of corticosterone in plasma. The OFT indicated that LEO and imipramine didn't reduce the spontaneous motor activity, while linalool and ketamine caused a significant decrease. CONCLUSION: Here we report by the first time that L. glaucescens leaves essential oil has anxiolytic effect by inhalation in mice, as well as linalool, and ß-pinene. This oil also maintains its antidepressant-like activity by this administration way, similarly to the previously determined intraperitoneally. Since inhalation is a common administration route for humans, our results suggest L. glaucescens essential oil deserve future investigation due to its potential application in aromatherapy.

Litsea glaucescens Kuth possesses bactericidal activity against Listeria monocytogenes.

Background: Litsea glaucencens Kuth is an aromatic plant used for food seasoning food and in Mexican traditional medicine. Among, L. glaucencens leaves properties, it has proven antibacterial activity which can be used against opportunistic pathogens like Listeria monocytogenes, a foodborne bacteria that is the causal agent of listeriosis, a disease that can be fatal in susceptible individuals. The aim of this work was to investigate the antibacterial activity of L. glaucescens Kuth leaf extracts against L. monocytogenes and to identify its bioactive components. Material and Methods: L. glaucences leaves were macerated with four solvents of different polarity (n-hexane, dichloromethane, ethyl acetate, and methanol). To determine the capacity to inhibit bacterial proliferation in vitro, agar diffusion and microdilution methods were used. Next, we determined the minimal bactericidal concentration (MBC). Finally, we determined the ratio of MBC/MIC. Metabolites present in the active methanolic extract from L. glaucescens Kuth (LgMeOH) were purified by normal-phase open column chromatography. The structure of the antibacterial metabolite was determined using nuclear magnetic resonance (1H, 13C, COSY, HSQC) and by comparison with known compounds. Results: The LgMeOH extract was used to purify the compound responsible for the observed antimicrobial activity. This compound was identified as 5,7-dihydroxyflavanone (pinocembrin) by analysis of its spectroscopic data and comparison with those described. The MIC and MBC values obtained for pinocembrin were 0.68 mg/mL, and the ratio MBC/MIC for both LgMeOH and pinocembrin was one, which indicates bactericidal activity. Conclusion: L. glaucences Kuth leaves and its metabolite pinocembrin can be used to treat listeriosis due the bactericidal activity against L. monocytogenes.

Chemical Composition of Litsea pungens Essential Oil and Its Potential Antioxidant and Antimicrobial Activities.

Litsea pungens is a plant with medicinal and edible properties, where the fruits are edible and the leaves have medicinal properties. However, there is limited research on the chemical and pharmacological activities of the plant. In this study, essential oils were extracted by steam distillation and their antioxidant and antibacterial activities were further evaluated. Gas chromatography-mass spectrometry (GC-MS) was used to identify the chemical components of L. pungens fresh fruit essential oil (FREO) and L. pungens fresh flower essential oil (FLEO), rapeseed oil (RO) and commercial Litsea oil (CEO). The results showed that 12 chemical components were identified in FREO. Twelve chemical components were identified from FLEO, four chemical components were identified from CEO, and thirteen chemical components were identified from RO. Except for RO, the other three oils were mainly composed of terpenes, among which limonene is the main chemical component. In terms of antioxidant activity, FREO, FLEO, CEO and RO have antioxidant capacity, mainly reflected in the scavenging DPPH free radicals and the iron ion chelating ability, and the antioxidant activity shows a certain dose effect, but the antioxidant activity of FLEO is the weakest among the four oils. Meanwhile, under the stress of hydrogen peroxide, CEO demonstrated a significant antioxidant protective effect on cells. It is worth mentioning that compared with the positive control, the FREO exhibited a better antibacterial rate. When the concentration of essential oil is 20 mg/mL, the bacteriostatic rate can reach 100%. Therefore, it could be a promising candidate among medicinal and edible plants.

Comparison of Chemical Compositions and Antioxidant Activity of Essential Oils from Litsea Cubeba, Cinnamon, Anise, and Eucalyptus.

The purpose of this study was to compare the antioxidant activity of litsea cubeba oil (LCO), cinnamon oil (CO), anise oil (AO), and eucalyptus oil (EUC) in vitro. The chemical compositions of the essential oils (EOs) were analyzed using gas chromatography-mass spectrometry (GC-MS). The antioxidant activity of the four EOs was evaluated through scavenging DPPH free radicals, chelating Fe2+, scavenging hydroxyl free radicals, and inhibiting yolk lipid peroxidation. The results showed that the major compounds found in LCO, CO, AO, and EUC are citral (64.29%), cinnamaldehyde (84.25%), anethole (78.51%), and 1,8-cineole (81.78%), respectively. The four EOs all had certain antioxidant activity. The ability to scavenge DPPH radical was ranked in the order of LCO > CO > AO > EUC. The hydroxyl radical scavenging ability was ranked in the order of EUC > CO > LCO > AO. The chelating Fe2+ capacity was ranked in the order of EUC > AO > CO > LCO. The yolk lipid peroxidation inhibition ability was ranked in the order of CO > AO > EUC > LCO. In different antioxidant activity assays, the antioxidant activity of the EOs was different. It was speculated that the total antioxidant activity of an EO may be the result of the joint action of different antioxidant capacities.

Deciphering antidiarrheal effects of Meda pata (Litsea glutinosa (Lour.) C.B.Rob.) leaf extract in chemical-induced models of albino rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Diarrhea is one of the leading causes of preventable death in developing countries, mainly caused by bacterial infections and traditional therapies are very common in diarrheal incidences. Meda Pata (Litsea glutionsa) has a long history of use as traditional medicine for diarrhea, dysentery, and spasm in Bangladesh, India, and some other Asian countries. AIM OF THE STUDY: This research reports the antidiarrheal effects of Meda Pata (Litsea glutinosa leaf extract, LGLEx) in animal models. The work has been supported by in silico molecular docking study to verify the effects. MATERIALS AND METHODS: The antidiarrheal effect of LGLEx was investigated in castor oil-induced diarrhea, magnesium sulfate-induced diarrhea, and gastrointestinal motility test models. Antidiarrheal effects were supported by a molecular docking study through an interaction between LGLEx's GC-MS analyzed imidazole-containing compounds and muscarinic acetylcholine receptor (PDB: 4U14) and 5-HT3 receptor (PDB: 5AIN). RESULTS: LGLEx potentially reduced the diarrheal incidences in in vivo assays reducing gastrointestinal motility. The maximum diarrheal inhibition was obtained in the castor oil-induced model (62.63%) and and BaSO4-induced model (73.14%), which were statistically significant (P < 0.05) when compared to the reference drug loperamide. In the castor-oil and BaSO4-induced models, peristaltic movement was reduced by 25.96% and 32.17%, respectively. Biochemical markers particularly IgE, C-reactive proteins, and serum electrolytes were significantly (P < 0.0) restored in treated groups. A Molecular docking analysis revealed that two compounds (1-Ethyl-2-hydroxymethylimidazole and 1,6-Anhydro-beta-D-glucofuranose demonstrated the highest binding affinity with target receptors muscarinic acetylcholine receptor (PDB: 4U14) and 5-HT3 receptor (PDB: 5AIN) confirming their drug likeliness. The findings indicate a high potential antidiarrheal impact that warrants further investigation for its therapeutic application.

Hepatoprotective potency of Litsea glutinosa (L.) C.B. Rob. leaf methanol extract on H2O2-induced toxicity in HepG2 cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Leaves of Litsea glutinosa (L.) (Lauraceae) are traditionally used to treat hepatitis and liver injury by Bangladeshi folks. However, the hepatoprotective study of leaves of L. glutinosa has not been supported by any research. AIM OF THE STUDY: To evaluate the antioxidant and hepatoprotective effects of leaves of methanol extract of L. glutinosa using the HepG2 cell line. Phytochemicals were identified with the help of a GC-MS study followed by In-silico docking of the promising compounds to justify our hepatoprotective effect. MATERIALS & METHODS: The dried leaves of L. glutinosa (LGAO) were extracted by Soxhlet using methanol as solvent. Antioxidant effects were investigated using Superoxide dismutase (SOD), Reduced glutathione (GSH), Glutathione peroxidase (GPx), and Malondialdehyde (MDA) in HepG2 cells against H2O2 intoxicated group. The In-vitro hepatoprotective effect of LGAO (100 µg/ml) was determined in HepG2 cells as compared with the Silymarin-treated standard group (100 µg/ml) along with morphological changes of cells. Twelve numbers of phytochemicals were identified by GC-MS study. In-silico studies are performed for their inhibitory effects against Peroxisome proliferator-activated receptor alpha (PPAR-α) and Transforming growth factor-beta1 (TGF-ß1) using AUTODOCK Tools-1.5.6 and Discovery studio 4.0. RESULTS: Methanol extract of L. glutinosa possesses (LGAO) significant (p < 0.0001) increase in SOD, GSH, and GPx levels and a decrease in MDA as compared with the control one. MTT assay in HepG2 cells showed a significant (p < 0.0001) increase in the percentage of cell viability in LGAO and Silymarin-treated group i.e., 71.98%, 88.59% respectively as compared with the H2O2 intoxicated group alone i.e., 22.74%. Restoration of cell architecture in HepG2 cells was obtained by the LGAO and Silymarin-treated group treated with H2O2. Further, the In-silico study of Neophytadiene compound showed the highest docking score -10.2 and -8.6 towards receptors. CONCLUSION: Methanol extract of leaves of L. glutinosa showed potential hepatoprotective effect In-vitro which justified our traditional claim. The presence of phytochemical Neophytadiene may be responsible for the said effect. Furthermore, molecular docking scores were consistent with the In-vitro results. They targeted the substantial inhibitory effects of Litsea glutinosa against receptors to establish the correlation between experimental and theoretical results.

Phytochemical Analysis and Understanding the Antioxidant and Anticancer Properties of Methanol Extract from Litsea glutinosa: In Vitro and In Vivo Studies.

Litsea glutinosa (L. glutinosa) is considered an evidence-based medicinal plant for the treatment of cancer, the leading cause of death worldwide. In our study, the in vitro antioxidant and in vivo anticancer properties of an essential ethno-medicinal plant, L. glutinosa, were examined using non-toxic doses and a phytochemical analysis was executed using gas-chromatography-mass-spectrometry. The in vitro antioxidant study of the L. glutinosa methanolic extract (LGBME) revealed a concentration-dependent antioxidant property. The bark extract showed promising antioxidant effects in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. The strongest antioxidant activity was demonstrated at the maximum concentration (50 µg/mL). The IC50 values of the LGBME and BHT were 5.51 and 5.01 µg/mL, respectively. At the same concentration, the total antioxidant capacity of the LGBME was 0.161 µg/mL and the ferric reducing antioxidant power assay result of the LGBME was 1.783 µg/mL. In the cytotoxicity study, the LD50 of the LGBME and gallic acid were 24.93 µg/mL and 7.23 µg/mL, respectively. In the in vivo anticancer-activity studies, the LGBME, particularly at a dose of 150 mg/kg/bw, showed significant cell-growth inhibition, decreased tumor weight, increased mean survival rate, and upregulated the reduced hematological parameters in EAC (Ehrlich's ascites carcinoma)-induced Swiss albino mice. The highest cell-growth inhibition, 85.76%, was observed with the dose of 150 mg/kg/bw. Furthermore, the upregulation of pro-apoptotic genes (p53, Bax) and the downregulation of anti-apoptotic Bcl-2 were observed. In conclusion, LGBME extract has several bioactive phytoconstituents, which confirms the antioxidant and anticancer properties of L. glutinosa.

Diverse sesquiterpenoids from Litsea lancilimba Merr. with potential neuroprotective effects against H2O2-induced SH-SY5Y cell injury.

Five undescribed sesquiterpenoids (1-5), and nine known sesquiterpenoids (6-14) were obtained from the fruits of Litsea lancilimba Merr. by LC-MS/MS molecular networking strategies. Litsemene A (1) possessed a unique 8-member ring through unexpected cyclization of the methyl group on C-10 of guaiane. Their structures were elucidated by spectroscopic techniques including IR, UV, NMR, HR-ESI-MS, and their absolute configurations were assigned by ECD calculations. All isolated sesquiterpenoids were analyzed by bioinformatics and evaluated for their neuroprotective effects against H2O2-induced injury in human neuroblastoma SH-SY5Y cells.

Litsea cubeba Essential Oil: Component Analysis, Anti-Candida albicans Activity and Mechanism Based on Molecular Docking.

The antifungal mechanism of plant essential oil has always been a concern in the agriculture and forestry science field. In this investigation, besides the evaluation of inhibitory activities of twenty-three essential oils against Candida albicans in vitro, identification and quantification of the chemical composition of Litsea cubeba essential oil by gas chromatography-mass spectrometry were investigated. Further development, we assessed the mechanism of L. cubeba essential oil against C. albicans by molecular docking. Litsea cubeba essential oil displayed the strongest inhibitory activity among these oils and the diameter of the circle against C. albicans was more than 50 mm. Maximum three components were identified with trans-citral (33.6%), cis-citral (30.3%), d-limonene (8.2%). Secretory aspartate protease (SAP5) and ß-1,3-glucan synthase (ß-1,3-GS) are two key enzyme proteins that inhibit the growth of C. albicans. Molecular docking studies reveal chemical binding forces of cis-citral, trans-citral and d-limonene to SAP5 are -21.76 kJ/mol, -22.18 kJ/mol and -24.27 kJ/mol, to ß-1,3-GS are -23.01 kJ/mol, -25.52 kJ/mol and -23.85 kJ/mol, respectively. The most preferable binding mechanism was observed against SAP5 and ß-1,3-GS due to hydrophobic interaction, as well as hydrogen bonding between citral molecules. The research results suggest the mechanism of chemical components in L. cubeba essential oil inhibits the growth of C. albicans, which provides a reference to the development and utilization of essential oil.

Small Molecule Accurate Recognition Technology accelerated isolation of structurally diverse sesquiterpenes from Litsea lancilimba Merr.

Four undescribed sesquiterpenes (1-4) and 20 known sesquiterpenes (5-24) were obtained from the fruits of Litsea lancilimba Merr. by Small Molecule Accurate Recognition Technology (SMART). The gross structures and the relative configurations of the new compounds were deduced by spectroscopic data analysis. The absolute configurations were defined by comparison of their experimental and calculated electronic circular dichroism (ECD) spectra data. All compounds were screened for their neuroprotective effects against H2O2-induced SH-SY5Y cells injury. Compounds 2, 3, 7, 8 and 13 exhibited comparable neuroprotective activity to the positive trolox at 50 µM.

Bioactive sesquineolignans from the twigs of Litsea cubeba.

In a continuing search for biological natural products with structure diversity from traditional Chinese herbs, five new sesquineolignans (1-5) were isolated from an ethyl acetate extract of the twigs of Litsea cubeba. Their structures were elucidated based on MS, 1D and 2D NMR spectroscopic data, as well as experimental electronic circular dichroism (ECD) spectra. Compounds 1-5 showed moderate inhibitory effects against LPS-induced NO production in RAW264.7 macrophages, with IC50 values of 16.2, 20.2, 22.1, 15.1, and 16.6 µmol·L-1, respectively.

Ameliorating Effect on Aß-Induced Alzheimer's Mice by Litsea cubeba Persoon Powder.

Alzheimer's disease (AD) is caused by excessive oxidative damage and aging. The objective of this study was to investigate the anti-dementia effect of LCP fruit powder on amyloid ß (Aß)-induced Alzheimer's mice. The composition of LCP essential oil was determined by gas chromatography/mass spectrometry. In addition, the water maze was used to evaluate the learning and memorizing abilities of the mice. The concentrations of malondialdehyde (MDA), protein carbonyl, phosphorylated τ-protein, and the deposition of Aß plaques in mouse brains were also assessed. The results showed that the main components of essential oils in LCP and d-limonene, neral, and geranial contents were 14.15%, 30.94%, and 31.74%, respectively. Furthermore, oral administration with different dosages of LCP significantly decreased the escape time (21.25~33.62 s) and distance (3.23~5.07 m) in the reference memory test, and increased the duration time (26.14~28.90 s) and crossing frequency (7.00~7.88 times) in the target zone of probe test (p < 0.05). LCP also inhibited the contents of MDA and the phosphor-τ-protein from oxidative stress, reduced the brain atrophy by about 3~8%, and decreased the percentage of Aß plaques from 0.44 to 0.05%. Finally, it was observed that the minimum dosage of LCP fruit powder (LLCP, 30.2 mg/day) could prevent oxidative stress induced by Aß and subsequently facilitate memory and learning deficits in Aß-induced neurotoxicity and cognitively impaired mice.

Transcriptomic Analysis of Drug-Resistance Acinetobacter baumannii under the Stress Condition Caused by Litsea cubeba L. Essential Oil via RNA Sequencing.

Litsea cubeba L. essential oil(LCEO) can affect the growth of drug-resistance bacteria. However, research on stress response of drug-resistant A. baumannii under sub-lethal LCEO concentrations had been limited so far. Therefore, transcriptomic analysisof A. baumannii under 1/2 minimum inhibitory concentration (MIC, 0.54 mg/mL) of LCEO was performed. Results of transcriptomic analysis showed that 320/352 genes were significantly up/down-regulated, respectively, in LCEO-treated A. baumannii. Both up and down-regulated genes were significantly enriched in three GO terms (oxidation-reduction process; oxidoreductase activity; oxidoreductase activity, acting on the CH-CH group of donors), which indicated that the redox state of A. baumannii was significantly affected by LCEO. LCEO may also inhibit aerobic respiration, synthesis of ketone bodies and the metabolism of some amino acids while, meanwhile, promoting fatty acid degradation of A. baumannii according to Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. The permeability and the stress of cell membrane of A. baumannii were significantly affected by LCEO. After crystal violet dyeing, the biofilm formation of A. baumannii was promoted/inhibited by extremely low/relatively high concentration of LCEO, respectively. LCEO and chloramphenicol have synergistic growth inhibitory effect against A. baumannii according to the Fractional Inhibitory Concentration Index (FICI) value = 0.375. Our results indicate that the growth of A. baumannii was inhibited by LCEO, and give insights into the stress response of A. baumannii under sub-lethal concentrations of LCEO. These results provided evidence that A. baumannii was inhibited by LCEO, and expanded knowledges of stress response of A. baumannii under sub-lethal concentration of LCEO.

An Overview on Total Valorization of Litsea cubeba as a New Woody Oil Plant Resource toward a Zero-Waste Biorefinery.

With the increasing global demand for edible oils and the restriction of arable land minimum in China, woody oil plants have gradually become the optimal solution to cover the shortage of current edible oil supply and to further improve the self-sufficiency rate. However, due to the lack of knowledge and technique, problems like "how to make full use of these plant resources?" and "how to guide consumers with reasonable data?" limit the development of woody oilseed industry towards a sustainable circular economy. In this review, several emerging unique woody oil plants in China were introduced, among which Litsea cubeba as a new woody oil plant was highlighted as a reference case based on its current research progress. Unlike other woody oil plants, essential oil rather than oil from Litsea cubeba has always been the main product through the years due to its interesting biological activities. Most importantly, its major component, citral, could be the base for other synthesized perfume compounds with added value. Moreover, the sustainable biorefinery of large amounts of waste residual after Litsea cubeba essential oil processing is now technically feasible, which could inspire a total valorization pathway for other woody oil plants to make more competitive plant-based products with both economic, social, and ecological benefits.

Effects of Thai Local Ingredient Odorants, Litsea cubeba and Garlic Essential Oils, on Brainwaves and Moods.

The functional food market is growing with a compound annual growth rate of 7.9%. Thai food recipes use several kinds of herbs. Lemongrass, garlic, and turmeric are ingredients used in Thai curry paste. Essential oils released in the preparation step create the flavor and fragrance of the famous tom yum and massaman dishes. While the biological activities of these ingredients have been investigated, including the antioxidant, anti-inflammatory, and antimicrobial activities, there is still a lack of understanding regarding the responses to the essential oils of these plants. To investigate the effects of essential oil inhalation on the brain and mood responses, electroencephalography was carried out during the non-task resting state, and self-assessment of the mood state was performed. The essential oils were prepared in several dilutions in the range of the supra-threshold level. The results show that Litsea cubeba oil inhalation showed a sedative effect, observed from alpha and beta wave power reductions. The frontal and temporal regions of the brain were involved in the wave alterations. Garlic oil increased the alpha wave power at lower concentrations; however, a sedative effect was also observed at higher concentrations. Lower dilution oil induced changes in the fast alpha activity in the frontal region. The alpha and beta wave powers were decreased with higher dilution oils, particularly in the temporal, parietal, and occipital regions. Both Litsea cubeba and turmeric oils resulted in better positive moods than garlic oil. Garlic oil caused more negative moods than the others. The psychophysiological activities and the related brain functions require further investigation. The knowledge obtained from this study may be used to design functional food products.

Plant-derived bioactive compounds produced by Streptomyces variabilis LCP18 associated with Litsea cubeba (Lour.) Pers as potential target to combat human pathogenic bacteria and human cancer cell lines.

To date, endophytic actinomycetes have been well-documented as great producers of novel antibiotics and important pharmaceutical leads. The present study aimed to evaluate potent bioactivities of metabolites synthesized by the strain LCP18 residing in the Vietnamese medicinal plant Litsea cubeba (Lour.) Pers towards human pathogenic bacteria and human cancer cell lines. Endophytic actinomycete strain LCP18 showed considerable inhibition against seven bacterial pathogens and three human tumor cell lines and was identified as species Streptomyces variabilis. Strain S. variabilis LCP18 was phenotypically resistant to fosfomycin, trimethoprim-sulfamethoxazole, dalacin, cefoxitin, rifampicin, and fusidic acid and harbored the two antibiotic biosynthetic genes such as PKS-II and NRPS. Further purification and structural elucidation of metabolites from the LCP18 extract revealed five plant-derived bioactive compounds including isopcrunetin, genistein, daidzein, syringic acid, and daucosterol. Among those, isoprunetin, genistein, and daidzein exhibited antibacterial activity against Salmonella typhimurium ATCC 14,028 and methicillin-resistant Staphylococcus epidermidis ATCC 35,984 with the MIC values ranging from 16 to 128 µg/ml. These plant-derived compounds also exhibited cytotoxic effects against human lung cancer cell line A549 with IC50 values of less than 46 µM. These findings indicated that endophytic S. variabilis LCP18 can be an alternative producer of plant-derived compounds which significantly show potential applications in combating bacterial infections and inhibition against lung cancer cell lines.

Deep eutectic solvent-homogenate based microwave-assisted hydrodistillation of essential oil from Litsea cubeba (Lour.) Pers. fruits and its chemical composition and biological activity.

As an important natural product, the sufficient separation of plant essential oil (EO) is helpful to improve its utilization value. In this work, deep eutectic solvent-homogenate based microwave-assisted hydrodistillation (DES-HMAHD) was developed and applied to isolate EO from the fruits of Litsea cubeba (Lour.) Pers. Different types of DES were investigated in terms of the EO kinetics and composition, among which oxalic acid/choline chloride (OA/ChCl) had obvious advantages. Following, molar ratio of OA and ChCl (1:1), water content (50%), liquid-solid ratio (12.5:1 mL/g), homogenate time (2 min), and microwave power (700 W) were found to be the optimum conditions. Gas chromatography-mass spectrometer (GC-MS) analysis showed that the EO isolated from DES-HMAHD contained a large proportion of m-cymene and trans-linalool oxide, which were quite different from the conventionally reported L. cubeba EO. In addition, the proposed DES-HMAHD resulted in higher separation efficiency and economic value, as well as lower environmental impact, as compared with other techniques. Afterwards, the EO isolated by different methods was evaluated from the perspective of biological activity. The EO obtained by DES-HMAHD showed higher antioxidant activity (DPPH and ABTS) but lower antifungal activity, which was related to its chemical composition. In general, DES-HMAHD produced a kind of L. cubeba EO with different components, which provided a scientific foundation for the sufficient isolation of plant EO and its application in the natural products.

In Vitro Antioxidant Activity of Litsea martabanica Root Extract and Its Hepatoprotective Effect on Chlorpyrifos-Induced Toxicity in Rats.

In Thailand, people in the highland communities whose occupational exposure to pesticides used the root of Litsea martabanica as a detoxifying agent. However, the scientific data to support the traditional use of this plant are insufficient. This study aimed to evaluate the antioxidant activity and anti-pesticide potential of L. martabanica root extract. Antioxidant properties were investigated by 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay, superoxide radicals scavenging assay, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay, ferric reducing antioxidant power (FRAP), and total phenolic content determination. In all assays, L. martabanica extracts and their fractions exhibited high antioxidant activities differently. The water extract is traditionally used as a detoxifying agent. Therefore, it was chosen for in vivo experiments. The rats received the extract in a way that mimics the traditional methods of tribal communities followed by chlorpyrifos for 16 days. The results showed that acetylcholinesterase activity decreases in pesticide-exposed rats. Treatment with the extract caused increasing acetylcholinesterase activity in the rats. Therefore, L. martabanica extract may potentially be used as a detoxifying agent, especially for the chlorpyrifos pesticide. The antioxidant properties of L. martabanica may provide a beneficial effect by protecting liver cells from damage caused by free radicals. Histopathology results revealed no liver cell necrosis and showed the regeneration of liver cells in the treatment group. L. martabanica extract did not cause changes in behavior, liver weight, hematological and biochemical profiles of the rats.