Rhus Verniciflua Research Articles

Performance of Drying Oil Modified Chinese Lacquer and Its Gilding Effect

This study explores the modification of traditional Chinese lacquer by incorporating boiled tung oil (BTO), boiled linseed oil (BLO), and turpentine oil (TO) to enhance its properties for gold leafing applications. Current traditional lacquers are limited by slow drying times and inconsistent surface quality, making their performance suboptimal for decorative gilding. The research addresses these gaps by investigating how varying oil types and concentrations (10%, 30%, and 50%) affect the lacquer’s drying time, viscosity, leveling properties, and overall gilding performance. Results indicate that TO-modified lacquer exhibits the best overall performance, showing the fastest drying time, highest glossiness, and smallest color variation, while BTO provides the smoothest surface and BLO ensures the best adhesion. These results demonstrate that the careful selection of oil type and concentration significantly improves lacquer’s functionality for gold leafing, offering a more efficient and aesthetically superior alternative to unmodified lacquers. This study provides valuable insights for optimizing traditional lacquer formulations for modern applications in gilding and decorative finishes.

Fustin, a Potent Phytochemical, Attenuates Scopolamine-induced Memory Impairment and Neurodegeneration by Modulating Neuroinflammation and Neurotransmitters.

Fustin, a photogenic flavanol found in the plant Rhus verniciflua Stokes, has been involved in multiple disease ailments and has a beneficial pharmacological effect and a history of use in traditional medicine. The present research aimed to study the impact of fustin on scopolamine (SCOP)-induced memory impairment and neurodegeneration by modulating neuroinflammation and neurotransmitters in rats. A total of 30 healthy Wistar rats were allocated into five groups (n=6). Group I- served as control and received saline solution (1mL/kg i.p.), group -II- fustin (100 mg/kg, orally), group -III -SCOP (1 mg/kg, i.p.), and group -IV and V were given fustin (50 and 100 mg/kg/p.o.) with SCOP (1 mg/kg, i.p.) for 14-days. After 14 days, 2 hours after SCOP injection, the Y-maze and Morris water maze (MWM) tests were performed. After behavioral tests rats were subsequently euthanized, and brain supernatants were used to estimate choline-acetyltransferase (ChAT), acetylcholinesterase (AChE), antioxidant [superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH)], and total protein, oxidative stress markers [nitrate and malondialdehyde (MDA)], pro-inflammatory markers [tumor necrosis factor (TNF-α), and Interleukins-1β (IL-1β) and IL-6]. Also, neurotransmitters such as serotonin (5-HT), dopamine (DA), ϒ-amino butyric acid (GABA), acetylcholine (Ach), and noradrenaline (NA) contents were performed. Fustin exhibited substantial behavioral improvement in the Y-maze measures spontaneous alterations percentage (SA%) and decreased latency time following the acquisition and prolonged time spent in the probe trial in the MWM test. Moreover, fustin inhibits enhanced neuroinflammatory cytokines and oxidative stress markers and improves the neurotransmitters. The findings of this study suggest that fustin inhibits SCOP impact on cognitive abilities in rats. The present investigation demonstrates that fustin, a potent phytochemical, effectively mitigated the behavioral and physiological changes induced by SCOP in rats. This was primarily achieved by modulating the levels of inflammatory response and neurotransmitters.

Multiple Omics Analyses Reveal Activation of Nitrogen Metabolism and Flavonoid Glycosylation in Toxicodendron vernicifluum Under High Temperature

Lacquer trees (Toxicodendron vernicifluum), economically vital, face high-temperature stress in summer. Transcriptomic, proteomic, and metabolomic analyses were employed to investigate the mechanisms by which lacquer trees respond to high temperatures. High-temperature treatment led to notable metabolite changes with 224 upregulated and 69 downregulated. Indole-3-acetic acid remained stable while abscisic acid decreased, with increases in jasmonic acid and jasmonoyl-L-isoleucine indicating complex hormonal responses. JAR1 and ABA 8′-hydroxylase encoding genes were upregulated. The rise in JAs boosted the alkaloid content and activated nitrogen transport. High temperatures also increased specific amino acids and upregulated aminotransferase and protease-encoding genes. Metabolomic analysis showed elevated flavonoid glycosides and the upregulation of glycosyltransferase genes. WPCNA found 35 protein modules involved in secondary metabolite biosynthesis, protein phosphorylation, and signal transduction. Protein–protein interaction analysis revealed MYC6’s link with flavonoid biosynthesis, indicating its role in promoting flavonoids.

Simplified Chinese Lacquer Techniques and Style Decoration on Luso-Asian Objects from the Late Sixteenth or Early Seventeenth Centuries

Simplified Chinese Lacquer Techniques and Style Decoration on Luso-Asian Objects from the Late Sixteenth or Early Seventeenth Centuries

Targeting insulin resistance: myricetin and isorhamnetin from Hardwickia binata, and luteolin from Hedysarum alpinum enhance glucose uptake and AMPK signaling in HepG2 cells

This study examined five plants (Xylopia aethiopica, Agave sisalana, Hardwickia binata, Hedysarum alpinum, and Toxicodendron vernicifluum) for their potential to address insulin resistance in type 2 diabetes. In-vitro assays showed that H. binata leaves and H. alpinum flowers inhibited α-glucosidase and α-amylase while enhancing glucose uptake in normal and insulin-resistant HepG2 cells. Phytochemical screening and SPE purification identified the key constituents responsible for the effects. The chromatographic and spectral analysis confirmed flavonoids in H. binata (myricetin, isorhamnetin, quercetin, kaempferol, and catechin) and H. alpinum (luteolin, quercetin, kaempferol, and apigenin). Myricetin, isorhamnetin, and luteolin significantly increased glucose uptake, enhanced hexokinase and pyruvate kinase activities, and promoted IRec and IRS-1 phosphorylation, modulating insulin signalling. They activated AMPK and Akt, with molecular docking confirming strong AMPK binding. These findings suggest that H. binata, H. alpinum, and their flavonoids are promising candidates for managing insulin resistance and type 2 diabetes, warranting further research.

Transcriptome and Metabolomic Analyses Reveal Tissue-Specific Glycosylation of Phenylpropanoids and Flavonoids in Toxicodendron vernicifluum.

Toxicodendron vernicifluum (Stokes) F. A. Barkley is a tree species used primarily for lacquer production. Our study utilized transcriptome and metabolomic analysis to investigate the biosynthesis of phenylpropanoids and flavonoids, specifically the glycosylated forms, in T. vernicifluum roots, stems, and leaves. HPLC-QTOF-MS/MS identified 186 compounds, with tissue-specific distributions revealed by PCA. Flavonoids and phenylpropanoids glycosides were significantly more abundant in leaves compared with roots and stems. Full-length sequencing uncovered 17,266 transcripts in T. vernicifluum. Gene expression analysis showed higher activity of phenylpropanoid and flavonoid biosynthesis pathways in leaves. Certain genes, such as CYP73A, 4CL, CRR, CYP84A/F5H, and CYP93C, displayed associations with compound content distributions. Root tissue exhibited a higher concentration of isoflavones. Notably, glycosyltransferase expression demonstrated significant correlations with glycosylated compounds' content. Biochemical validation confirmed the involvement of TvPB_c0_g2904, encoding a UDP-glucosyltransferase, in genistin biosynthesis in T. vernicifluum.

In vitro propagation of triploid Toxicodendron vernicifluum (Stokes) F. A. Barkl

AbstractTriploid lacquer trees have a higher yield of raw lacquer and greater stress resistance; however, it is challenging to develop efficient and rapid seedling culture techniques because of the influence of metabolites with raw lacquer. In this study, the stem segments of a triploid lacquer tree were used to investigate the effects of explant sterilization treatment, different combinations of exogenous hormone concentrations on the induction of axillary buds, seedling development, and rooting, as well as transplanting substrate ratios. The results showed that the optimal combination of disinfection treatment for triploid Toxicodendron vernicifluum (Stokes) F. A. Barkl explants involves 75% alcohol immersion for 10 s, followed by 2.0% benzalkonium chloride treatment for 1 min and 0.1% HgCl2 treatment for 4 min. The suitable medium for axillary bud induction was Murashige and Skoog (MS) containing 0.1 mg•L−1 zeatin (ZT) and 0.1 mg•L−1 6-benzylaminopurine (6-BA), resulting in a high induction rate of 95.0%. Use of 1/2 MS supplemented with 0.5 mg•L−1 6-BA and 0.3 mg•L−1 2,4-dichlorophenoxyacetic acid (2,4-D) was the most effective for axillary bud proliferation. The combination of 1/2 MS containing 0.1 mg•L−1 6-BA, 0.5 mg•L−1 2,4-D, 0.5 mg•L−1 indole-3-butyric acid (IBA), and 0.2% activated carbon (AC) was an optimum for hardening-off. With woody plant medium (WPM) supplemented with 0.5 mg•L−1 naphthaleneacetic acid (NAA) and 0.5 mg•L−1 2,4-D and 0.5 g•L−1 AC as a rooting medium, the rooting rate was 67.8%. Also, the appropriate transplanting substrate ratio for triploid Toxicodendron vernicifluum (Stokes) F. A. Barkl was grass charcoal:laterite:humus = 1:1:1. Collectively, the results provided the technical assurance for seedling scale multiplication and propagation, facilitating its application in production.

Magnetic bio-based Fe3O4@urushiol-Fe polymeric nanoparticles for efficient photothermal sterilization

Many advantages of photothermal sterilization make it very promising in the field of sterilization. Biomass micro-nanoparticles with photothermal properties are considered worthy of development as photothermal sterilization materials. Urushiol, the main component of natural sap from lacquer tree, was applied to react with green-vitriol by the adjusted the concentrations of ferrous ion through the chemical synthesis method to prepare a novel magnetic composite nanoparticle with Fe3O4 as the central core wrapped by urushiol-Fe chelate polymer. Under 808 nm near-infrared irradiation (0.12 W cm−2), the Fe3O4@urushiol-Fe polymeric nanoparticles were rapidly heated up to a maximum temperature of 104.9 ℃, implying good photothermal conversion performance. The nanoparticles were applied for the effective inactivation of bacteria such as Escherichia coli and Staphylococcus aureus. The optimal dose and irradiation power for sterilization were 0.5 mg and 1 W cm−2, respectively. The composite nanoparticles exhibited good photothermal conversion stability even after multiple photothermal heating and photothermal sterilization. The biomass magnetic composite Fe3O4@urushiol-Fe polymer nanoparticles had the advantages of simple preparation, high efficiency of photothermal conversion, significant sterilization effect, and easy collection, which demonstrated a broad application prospect in the field of photothermal sterilization.

Effects of Laccase and Transglutaminase on the Physicochemical and Functional Properties of Hybrid Lupin and Whey Protein Powder.

Plant-based protein is considered a sustainable protein source and has increased in demand recently. However, products containing plant-based proteins require further modification to achieve the desired functionalities akin to those present in animal protein products. This study aimed to investigate the effects of enzymes as cross-linking reagents on the physicochemical and functional properties of hybrid plant- and animal-based proteins in which lupin and whey proteins were chosen as representatives, respectively. They were hybridised through enzymatic cross-linking using two laccases (laccase R, derived from Rhus vernicifera and laccase T, derived from Trametes versicolor) and transglutaminase (TG). The cross-linking experiments were conducted by mixing aqueous solutions of lupin flour and whey protein concentrate powder in a ratio of 1:1 of protein content under the conditions of pH 7, 40 °C for 20 h and in the presence of laccase T, laccase R, or TG. The cross-linked mixtures were freeze-dried, and the powders obtained were assessed for their cross-linking pattern, colour, charge distribution (ζ-potential), particle size, thermal stability, morphology, solubility, foaming and emulsifying properties, and total amino acid content. The findings showed that cross-linking with laccase R significantly improved the protein solubility, emulsion stability and foaming ability of the mixture, whereas these functionalities were lower in the TG-treated mixture due to extensive cross-linking. Furthermore, the mixture treated with laccase T turned brownish in colour and showed a decrease in total amino acid content which could be due to the enzyme's oxidative cross-linking mechanism. Also, the occurrence of cross-linking in the lupin and whey mixture was indicated by changes in other investigated parameters such as particle size, ζ-potential, etc., as compared to the control samples. The obtained results suggested that enzymatic cross-linking, depending on the type of enzyme used, could impact the physicochemical and functional properties of hybrid plant- and animal-based proteins, potentially influencing their applications in food.

Decorative art of Russian painted spinning wheels and the art of painted lacquer products in China during the Warring States of Qi Lien

The article is devoted to the comparison of Mezen painted spinning wheels actively produced in Arkhangelsk province (Russia) in the XIX century and objects of Chinese art of Qi Lien painting of the Warring Kingdoms period. In this era, the skill of creating Chinese lacquer products was very developed, and the spinning wheel industry of the XIX century became the basis for the existence of a vital craft for Russian people. The spinning wheels were decorated with colored paintings with repetitive plots. The subjects of the study represent the most important part of the folk art of the two cultures, reflecting at the same time the aesthetic and spiritual preferences of the population. Their prevalence in both cases made it possible to identify the commonality of artistic techniques used by folk craftsmen. Scientific work assigns an important role to the techniques of manufacturing household items that demonstrate the prevailing artistic environment at the time of their regular use. The leading method of research is formal stylistic analysis, revealing characteristic compositional features. Comparative analysis makes it possible to identify similarities and differences in the works of DPI, which make it possible to hypothesize a paradoxical objective community. Considerable attention is also paid to the coloristic analysis and symbolic meaning of the murals. The scientific novelty of the study is due to the presence of a very limited number of sources mentioning the possible similarity of the two fields of folk art, none of which is fully devoted to the formal and stylistic features of objects created by unknown masters. The article closes this gap, aiming to discover specific unifying features. Its tasks become a detailed study of plots, compositions, techniques and materials used. The research allows us to come to the conclusion that the work of both Russian and Chinese artists reflected the main artistic aspirations of contemporaries, who often endowed objects and phenomena with symbolic meaning. There is a noticeable interest in the use of wood, the use of warm shades and the embedding of patterns in compositions. There is a similarity in the desire to reflect reality when including plant and animal motifs in their works. Also, the decorative and planar nature of the painting combines the rich details of the product. The relevance of the research is due to the convergence of Russian and Chinese cultures, so that the study of the issue can contribute to finding new points of spiritual contact.

Characterization and identification of an archaeological “lacquer” pipe

A pipe with red coating on the surface was excavated from an archaeological site in Sweden, which is supposed to be a lacquer ware imported from China due to the admiration and pursue of lacquer wares from Asia by Europeans during sixteenth to eighteenth centuries. However, materials such as shellac and resins were often used to imitate lacquer during that time in Europe. To determine whether the pipe was Chinese lacquer ware or not, attenuated total reflection of fourier transform infrared spectroscopy (ATR-FTIR), thermally-assisted hydrolysis and methylation pyrolysis gas chromatography-mass spectrometry (THM-Py-GC/MS) were conducted. The detection of significant amount of aleuritic acid, laccijalaric acid, laccishellolic acid, shellolic acid and jalaric acid represents that shellac is the main material used for the pipe coating rather than Chinese lacquer. Long chain fatty alcohols were found in the sample, indicating that the shellac is un-dewaxed. In addition, pine resin and turpentine were also found as additives in the pipe coating. Furthermore, pigments in the coating were determined as cinnabar and carbon black by scanning electron microscopy with element energy dispersive spectroscopy (SEM–EDS) and Raman spectroscopy. The results could definitely support the conservation of the pipe, and also provide the evidence of the cultural exchange between Europe and Asia.

中國古代 住居文化에 나타나는 風水觀念

In this paper, the Fengshui idea(風水觀念) of the housing culture in the Chinese Pre-Qin era was examined by referring to classics and books of philosophers. As humans lead their lives in a particular space after birth, everyone adapts to spaces. The first living place changed from a natural cave to Amdong(岩洞, a rock valley), Sogeo(巢居, a tree house), Hyeolgeo(穴居, a cave), Bonggeo(蓬居, a house with a roof of mugwort stalks) and etc. Particularly in case of Bonggeo, it had the same dwelling condition as today's tents, which has great implications. It shows that human race had already understood science as a type of environment satisfying basic life they deserved to enjoy, and that, by understanding the progress of applied technology, they improved the quantity and quality of their residence and therefore solved the problem of their survival. In addition, the ecological environment is presented in accordance with the characteristics of the region. Momul(毛物) refers to mammals, Rinmul(鱗物) fish, Wumul(羽物) poultry, Gaemul(介物) turtles, animals without fur shellfish, plants of Jomul(皂物) oaks or chestnut trees, Gomuk(膏物) royal foxglove trees or lacquer trees, Heulmul(覈物) peaches or plum trees, Hyeopmul(莢物) herbs like shepherd's purse, and Chongmul(叢物) plants like ramie and reeds. Like this, each geographical environment reflects the weight of life of the people or animals and plants living there as it is.

Vortex-blending matrix solid-phase dispersion and UPLC-Q-TOF/MS were proposed to extract and examine the urushiols from Toxicodendron vernicifluum bark

Toxicodendron vernicifluum bark has been used for many years as a component in foods and as a traditional herbal medication. Unfortunately, the presence of urushiols, which induce allergies, limits its application. This study used a vortex-blending matrix solid-phase dispersion microextraction technique to extract urushiols from Toxicodendron vernicifluum bark. HPLC was used to evaluate the amounts of the extracted urushiols (15:0, 15:1, 15:2, and 15:3). The modified magnetic adsorbent was prepared through an in situ coprecipitation method and characterized using a variety of techniques. The optimized extraction conditions are as follows: using magnetic Zeolite Socony Mobil-Five as an adsorbent, a 1:2 sample/adsorbent ratio, 2.5 min of vortex-blending time, 4 mL of 0.1% (V/V) trifluoroacetic acid-methanol as the elution solvent and 8 min of ultrasound time. There was good linearity and high repeatability in the method. Furthermore, the limits of detection for the urushiols ranged from 0.20 to 0.50 μg/mL. Under the optimized conditions, 50 compounds were identified by ultra high performance liquid chromatography and quadrupole time-of-flight mass spectrometry. These compounds included 8 phenolic acids, 9 monomeric urushiols, 11 urushiol dimers, 10 other components, and 11 flavonoids. The suggested approach, which has the advantages of few stages and high extraction efficiency over existing extraction procedures, is a potentially useful method for obtaining and evaluating urushiols in raw materials or extracts.

Introduction of Chinese Lacquer from the Perspective of Chemistry: Popularizing Chemistry in Lacquer and Inherit Lacquer Art

Introduction of Chinese Lacquer from the Perspective of Chemistry: Popularizing Chemistry in Lacquer and Inherit Lacquer Art

Quantitative Detection of Thitsiol and Urushiol as Markers from the Gluta usitata Lacquer Tree Using HPLC.

Lacquer sap has been traditionally used in coatings and artwork. Suitable types of lacquer are required to preserve and restore artifacts. Recently, unsuitable cashew nut shell liquid (CNSL) has often been mixed with lacquer sap, so it is necessary to identify the characteristics of lacquer sap by the production area. However, research is still focused on urushiol and laccol. In this study, Myanmarese lacquer sap collected from Gluta usitata, which contains thitsiol as the main component, was analyzed by HPLC to quantify thitsiol using the standards 3-(10-phenyldecyl) benzene-1,2-diol (thitsiol 16) and 3-(8Z,11Z-pentadecadienyl)-benzenediol (urushiol 15:2) as markers, and calibration curves were plotted. The coefficients of determination (R2) for thitsiol 16 and urushiol 15:2 were 0.9985 and 0.9983, respectively. In addition, a blind test was conducted to confirm that accurate quantitative analysis was possible even when Myanmarese lacquer was mixed with lacquer from another production area, which contained urushiol as the main component, and CNSL, which contained cardol, a completely different catechol. Quantitative analysis of thitsiol 16 and urushiol 15:2 in Myanmarese lacquer using HPLC can be used to evaluate the quality of lacquer sap and for more sophisticated activities such as restoration by classifying differences in lacquer sap by the production area.

A Comparative Aesthetics Analysis on Song Dynasty Lacquer Dish in the Form of Plum Blossoms with a Red-brushed Pattern of Two Phoenixes

The Chinese artcraft in Song and Ming Dynasty set a standard that is understood as both unique and influential. Through comparative research, the lacquered Artcraft in East Asia and Europe would provide a holistic view of how Chinese lacquer art craft transferred through dynasties. Two Chinese crafts, Ming Yongle red-painted tea flower round plate and the Song dynasty Lacquer dish in the form of plum blossoms with a red-brushed pattern of two phoenixes are illustrated. It then presents a gilt-bronze inlaid lacquer vessel from France in the reign of Louis XV, made by the Japanese and European Lacquer Bureau, and one can see the great difference between it and the two previous ones made in China. It is inlaid on the top surface with figures, carriages, and horses, as well as with figures of mountains, rocks, and trees, with most of the figures concentrated on the left side, while the right side is left relatively empty of white space. It is argued that from several aspects, the comparison is worthwhile.

Environmental-friendly biomass-based Janus ink/urushiol modified cotton fabric for efficient solar-driven interfacial evaporation

Much attention has been paid to the interfacial solar-thermal conversion method for water resource purification. According to the hydrophilicity of ink carbon particles and the amphiphilicity of urushiol molecules (the main compound of Chinese lacquer), a novel environmentally friendly biomass Janus ink/urushiol modified cotton fabric was successfully prepared and exhibited one hydrophilic side and one hydrophobic side through simple immersion and spraying treatments. The Janus fabric displayed excellent water transport behavior, mechanical stability, thermal conductivity, and photothermal conversion performance. Under one stimulated solar radiation, the temperature of the Janus fabric increased to 85 °C in 2 min. Additionally, a photothermal vapor device prepared using a polyethylene ring and the Janus fabric demonstrated a high conversion efficiency of 94.3% with an impressive evaporation rate of 1.64 kg m−2h−1, which was 3.35 times the rate of water evaporation in the absence of the modified fabric. The Janus fabric showed satisfactory resistance to ultraviolet radiation and pH values. After 8 cycles (every 10 h) of exposure to outdoor sunlight, the modified fabric showed a slightly decreased evaporation rate, which could be restored to the previous level by re-spraying ink on the modified fabric. In the concentrated salt solutions, the solar-driven evaporator displayed excellent salt rejection capacity. During the desalination of high-concentration saline water, the Janus fabric showed acceptable diurnal correspondence. After desalination, the water quality reached the required standards for drinking water. In particular, the B3+ content droppingto 0.33 mg L−1(below the thresholdof 0.5 mg L−1). The solar steam generator also showed remarkable purifying capabilities for wastewater containing heavy metals and organic dyes. The Janus ink/urushiol fabric, prepared in an easy way, has a wide range of applications in seawater desalination and sewage treatment, which can be applied for mitigation of freshwater crises and environmental remediation.

Systematic Investigation into Evolution of Materials and Techniques Used in Lacquer Lian from the Warring States Period to the Yuan Dynasty

In order to investigate the evolution of Chinese lacquering techniques, seven pieces of lacquer Lian from the Warring States Period to the Yuan Dynasty (475 BC–1368 AD) were analyzed by means of cross-section observation, Raman spectroscopy (RS), and thermally assisted hydrolysis and methylation pyrolysis coupled with gas chromatography/mass spectroscopy (Py-GC/MS). The results revealed that the lacquer Lian consisted of a three-layer structure, encompassing a pigment layer on the surface, an undercoat layer in the middle, and a ground layer. The red mineral pigment utilized was cinnabar, while a combination of Chinese lacquer and drying oil served as the primary organic material. Although lacquering techniques had undergone minimal changes from the Warring States Period to the Yuan Dynasty, the species of drying oil had changed, based on the fact that boiled tung oil was found in the ground layer of lacquerware from the Song Dynasty and the Yuan Dynasty. The present research provides direct evidence for the inheritance and development of Chinese lacquer technology.

Evaluation of the Antifungal Effect of Rhus verniciflua Stokes Extract for Oral Application Potential.

Background and Objectives: This study confirms the possibility of using Rhus verniciflua Stokes (RVS) extract as a natural treatment for oral candidiasis. Materials and Methods: RVS was extracted with 70% ethanol to examine the antioxidant activity through polyphenol, flavonoid content, and DPPH (1,1-diphenyl-2-picrylhydrazyl). To evaluate the antifungal effect against Candida albicans (C. albicans; KCTC 7965/ATCC 10231) and evaluate the stability of RVS, a water-soluble tetrazolium salt (WST-1) assay was performed in human keratinocytes (HaCaT). Results: The findings revealed that RVS extract has fairly high antioxidant activity. The clear zones of the RVS extract against C. albicans increased in diameter due to the inhibition of fungal growth at higher concentrations. Treatment with the 1.25 mg/mL RVS extract had a more than 99% antifungal effect against C. albicans, and the 20 mg/mL RVS extract had a 100% antifungal effect. The WST-1 assay showed that the RVS extract induced low cell viability in the HaCaT cells, which inhibited their proliferation, and the RVS extract is also toxic to normal cells. Conclusions: Although the RVS extract with high antioxidant activity showed clear antifungal activity against C. albicans, it exhibited a low survival rate. Therefore, the development of a safe natural antibiotic is necessary.

Polysaccharide metabolism in Anacardiaceae (Asian lacquer) cross-linked polymers elucidated using in situ trimethylsilylation pyrolysis-gas chromatography–mass spectrometry

Carbohydrates from polysaccharides in natural thermoset Anacardiaceae polymers of Gluta usitata, Toxicodendron succedaneum and Toxicodendron vernicifluum were identified using pyrolysis-gas chromatography–mass spectrometry with in situ trimethylsilylation. Pyrolysates resulting from the pyrolytic intermolecular chain scission of the polysaccharides were used to elucidate monomeric units. Polysaccharides, dispersed in the phenolic lacasse catalysed cross-linked macromolecules, showed to be metabolised through various catabolic and anabolic routes. Galactose functionalities, abundantly present in the polysaccharides were determined to be enzymatically converted to glucose-6-phosphate, followed by conversion via glycolysis and pentose phosphate pathways. Determination of specific routes of carbohydrate modification via glycolysis and pentose phosphate pathways facilitated differentiating G. usitata, T. succedaneum and T. vernicifluum polymers, based on the carbohydrate content. It was also found that uronic type acids, present as end groups of the branched polysaccharide structure, were biochemically converted to aldonic acids. Following the pentose phosphate and glycolysis routes, carbohydrates in G. usitata and T. vernicifluum polymers showed to be further modified via shikimate and cinnamate pathways to produce phenylpropanoid compounds. Parent molecules and pyrolysis products thereof were verified using analytical standards of high purity. The mass spectra and Kovats retention indices were compiled in an AMDIS library, which can be made available on request.