Canarium Album Research Articles

Phenylpropanoid metabolism may dominate the black spot resistance of Chinese olive (Canarium album)

Phenylpropanoid metabolism may dominate the black spot resistance of Chinese olive (Canarium album)

Transcriptomic and Metabolomic Analysis Reveals the Potential Roles of Polyphenols and Flavonoids in Response to Sunburn Stress in Chinese Olive (Canarium album).

Sunburn stress is one of the main environmental stress factors that seriously affects the fruit development and quality of Chinese olive, a tropical and subtropical fruit in south China. Therefore, the understanding of the changes in physiological, biochemical, metabolic, and gene expression in response to sunburn stress is of great significance for the industry and breeding of Chinese olive. In this study, the different stress degrees of Chinese olive fruits, including serious sunburn injury (SSI), mild sunburn injury (MSI), and ordinary (control check, CK) samples, were used to identify the physiological and biochemical changes and explore the differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) by using transcriptomics and metabolomics. Compared with CK, the phenotypes, antioxidant capacity, and antioxidant-related enzyme activities of sunburn stress samples changed significantly. Based on DEG-based KEGG metabolic pathway analysis of transcriptomics, the polyphenol and flavonoid-related pathways, including phenylpropanoid biosynthesis, sesquiterpenoid, and triterpenoid biosynthesis, monoterpene biosynthesis, carotenoid biosynthesis, isoflavonoid biosynthesis, flavonoid biosynthesis, were enriched under sunburn stress of Chinese olive. Meanwhile, 33 differentially accumulated polyphenols and 99 differentially accumulated flavonoids were identified using metabolomics. According to the integration of transcriptome and metabolome, 15 and 8 DEGs were predicted to regulate polyphenol and flavonoid biosynthesis in Chinese olive, including 4-coumarate-CoA ligase (4CL), cinnamoyl-CoA reductase (CCR), cinnamoyl-alcohol dehydrogenase (CAD), chalcone synthase (CHS), flavanone-3-hydroxylase (F3H), dihydroflavonol 4-reductase (DFR), and anthocyanidin synthase (ANS). Additionally, the content of total polyphenols and flavonoids was found to be significantly increased in MSI and SSI samples compared with CK. Our research suggested that the sunburn stress probably activates the transcription of the structural genes involved in polyphenol and flavonoid biosynthesis in Chinese olive fruits to affect the antioxidant capacity and increase the accumulation of polyphenols and flavonoids, thereby responding to this abiotic stress.

Structure Characteristics, Variation of Main Quantitative Traits, and Probability Grading of Chinese Olive (Canarium album) Seeds

In order to comprehensively describe and evaluate Chinese olive seeds, this study examined 33 varieties (strains) of Chinese olive seeds to address the limitations of previous research on quantitative trait variation and grading among Chinese olive seed varieties (strains). The research specifically focused on evaluating the morphological characteristics, seed locule structure, embryo composition, and phenotypic quantitative traits of Chinese olive seeds. The results indicated that Chinese olive seeds consisted of a core, seed coat, and embryo. Typically, the core contained two to four locules, with each locule containing zero to one embryos. Eight distinct structural variations were identified, with the number of locules per seed ranging from two to four and the number of embryos ranging from one to four. The most common structural types were ‘3-locule 1-embryo’ and ‘3-locule 2-embryo’, each occurring in 100% of the varieties (strains) studied. These two structural types also had a high average proportion within each variety (line), accounting for 50.17% and 42.06%, respectively. The average dimensions of a seed were 31.20 mm in length and 10.89 mm in width, with a shape index of 2.89 and weighing 1.55 g. These quantitative traits displayed significant variation, with the coefficient of variation being highest for single seed weight (19.35%) and lowest for seed length (9.39%). Normality tests revealed that seed width, seed length, and single seed weight followed a normal distribution. These traits were categorized into five levels based on specific points, with probabilities of occurrence approximately 10%, 20%, 40%, 20%, and 10%, respectively. The findings of this study are crucial for understanding and utilizing Chinese olive seed traits and provide valuable insights for the establishment of seed trait standards and data normalization.

Identification of MYB Transcription Factor, a Regulator Related to Hydrolysable Tannin Synthesis in Canarium album L., and Functional Analysis of CaMYBR04.

Hydrolysed tannins (HTs) are polyphenols, which are related to the astringency, flavour, colour, stability, medicinal value and other characteristics of many fruits and vegetables. The biosynthetic mechanism of the majority of HTs remains unknown, and many biosynthetic pathways of HTs are speculative conclusions that have not been confirmed. The fruit of Canarium album L. (Chinese olive), which is notable for its pharmacological and edible properties, is rich in HTs. The fruit has a distinctive bitter and astringent taste when initially consumed, which mellows to a sweet sensation upon chewing. HTs serve as the primary material basis for the formation of the Chinese olive fruit's astringent quality and pharmacological effects. In this study, the fruit of C. album Changying was utilised as the research material. The objective of this study was to provide a theoretical basis for the quality control of Chinese olive fruit and the application and development of its medicinal value. In addition, the study aimed to identify and screen related MYB transcription factors involved in the synthesis of HTs in the fruit and to clarify the mechanism of MYBs in the process of synthesis and regulation of HTs in Chinese olive fruit. The principal findings were as follows. A total of 83 differentially expressed Chinese olive MYB transcription factors (CaMYBs) were identified, including 54 1R-MYBs (MYB-related), 25 2R-MYBs (R2R3-MYBs), 3 3R-MYBs, and 1 4R-MYB. Through trend analysis and correlation analysis, it was found that CaMYBR04 (Isoform0032534) exhibited a significantly higher expression (FPKM) than the other CaMYBs. The full-length cDNA sequence of CaMYBR04 was cloned and transformed into strawberry. The results demonstrated that CaMYBR04 significantly enhanced the fruit's hydrolysable tannin content. Consequently, this study elucidated the function of CaMYBR04, a regulator of the Chinese olive fruit hydrolysable tannin synthesis pathway, and established a theoretical foundation for the synthesis and regulation of fruit HTs.

Diaporthe arecae is a new pathogen causing Chinese olive (Canarium album) dieback in China

Chinese olive (Canarium album Raeusch.) is an economically important fruit crop with a long history in China as a medicinal plant. However, it is prone to fungal pathogens. In recent survey, Chinese olive trees showing shoot and twigs dieback, and in severe cases, leaf defoliation and branches withered, were observed in the field. These symptoms were never observed in Chinese olive and can be considered a novel dieback disease. The responsible pathogen was isolated and purified from shoot and twigs samples of dieback diseased Chinese olive collected from in Fujian Province, and was identified as Diaporthe arecae based on morphological characteristics and multi-genes phylogenetic analysis. Subsequent pathogen inoculations on detached leaves and branches and in seedlings confirmed its pathogenicity in Chinese olive causing dieback disease, in accordance to Koch's postulates. This is the first report of dieback disease caused by D. arecae in Chinese olive worldwide.

Study on Dormant and Germination Characteristics of Chinese Olive (Canarium album) Seeds

This study aimed to determine the dormancy type of Chinese olive seeds and improve their germination rate. The water permeability and germination-inhibiting substances of Chinese olive seeds were assessed. Low-temperature stratification and soaking in a GA3 solution were implemented to measure the time lag, initial time, germination rate, and germination potential of the seeds. The findings revealed that the seed coat exhibited poor water permeability, which negatively influenced the germination rate. Additionally, Chinese olive seeds contained substances that inhibited germination. The duration of low-temperature stratification (at 4 ± 1 °C) gradually diminished the dormancy of Chinese olive seeds, resulting in early and rapid germination. The germination rate significantly increased, with the percentage of seed germination rising from 0% to 42.33% within 60 days of stratification. Furthermore, combining low-temperature stratification with different concentrations of GA3 notably enhanced the germination rate. The optimal concentrations of gibberellins for 40 and 60 days of stratification were determined to be 300 and 100 mg/L, respectively. These results indicate that Chinese olive seeds possess non-deep physiological dormancy.

First report of Botryosphaeria dothidea causing fruit rot on Chinese olive (Canarium album Raeusch.) in Guangdong province of China.

Chinese olive (Canarium album Raeusch.) is a traditional Chinese medicinal plant, mainly cultivated in Guangdong and Fujian provinces in China (Lai et al. 2022). In October 2023, Chinese olive fruit spots were observed in all the Chinese olive orchards surveyed in Chaozhou city (23.75°N, 116.67°E) of Guangdong, with an incidence up to 15%. Early disease symptoms on fruits appeared as circular or irregular, dark brown to black spots with yellowish lesions, and later the spots slowly coalesced to form large necrotic areas, which seriously affected the fruit marketability. To isolate the causal agent, small pieces (~0.3 mm2) of fruit tissue were excised from the lesion margins, and surface-disinfested with 75% (v/v) ethanol for 1 min, followed by 1% NaClO for 3 min, and rinsed three times with sterile water. The pieces were then placed on potato-dextrose-agar (PDA) and incubated at 27°C. Ultimately, four fungal isolates were obtained with similar morphology phenotypes, colonies initially appeared white with irregular margins and after 4-6 days turned dark gray gradually with dense aerial myceliu. Microscopy revealed conidia were single-celled, hyaline, aseptate, fusiform to subclavate, and measured 18.1-22.5 μm × 6.4-9.3 μm (19.8 × 7.4 m on average, n = 30), which were consistent with those descriptions of Botryosphaeria dothidea (Vasić et al. 2013; Zhang et al. 2023). To further identity the isolates, partial sequences of ribosomal transcribed spacer (ITS), translation elongation factor 1-α (TEF1-α), and β-tubulin (TUB2) genes were amplified using primers ITS1/ITS5, TEF-F/R, TUB2-F/R, respectively (Xu et al., 2023; Hong et al. 2006). The sequences of four isolates were identical, and those of representative strain GDCZ-1 were deposited in GenBank (ITS, OR584295; TEF1-α, OR685157; TUB2, OR685158). Using Neighbor-Joining algorithm, phylogenetic tree based on concatenated sequences of ITS, TEF1-α, and TUB2 showed that GDCZ-1 clustered with B. dothidea. To fulfill Koch's postulates, pathogenicity tests were performed on healthy Chinese olive fruits using the needle-prick inoculation method. The fruits were wounded with a sterile needle at the equatorial area (depth of 3-4 mm), and inoculated with 10 µL of spore suspension (106 /mL). The control fruits were inoculated with sterile water. Inoculated fruits were placed in sterile plastic containers to maintain high relative humidity (almost 100%) and incubated at 27°C. After 4 days, the inoculated fruits showed similar symptoms with those observed in the field infected fruits, while the control remained asymptomatic. Pathogen re-isolated from the inoculated fruits showed identical morphological characteristics to the original isolate GDCZ-1. As far as we know, fruit rot caused by Alternaria alternata has been recently reported on C. album in China (Shao et al. 2024). To our knowledge, this is the first report of B. dothidea causing fruit rot disease on C. album in Guangdong. Our report will provide crucial information for studying the epidemiology and management of this disease.

De Novo Transcriptome Analysis by PacBio SMRT-Seq and Illumina RNA-Seq Provides New Insights into Polyphenol Biosynthesis in Chinese Olive Fruit

Polyphenols play a crucial role in fruit flavor. To elucidate the mechanism of fruit polyphenol metabolism, we constructed a transcriptome atlas through PacBio single-molecule real-time (SMRT) sequencing and Illumina next-generation sequencing (NGS) using Canarium album (Lour.) Raeusch., which is a fantastic fruit rich in polyphenolic compounds. In this work, PacBio full-length transcriptome assembly generated 135,439 isoforms with an average length of all isoforms of 2687.94 bp and an N50 length of 3224 bp. To gain deeper insights into the molecular mechanisms of polyphenol biosynthesis in C. album, we constructed twelve RNA-Seq libraries from four developmental stages of the fruits. We identified a total of 28,658 differentially expressed genes (DEGs). We found that many DEGs were involved in metabolic pathways, biosynthesis of secondary metabolites, biosynthesis of antibiotics, starch and sucrose metabolism, and plant hormone signal transduction. Here, we report the expression profiles of 215 DEGs encoding 27 enzymes involved in the polyphenol biosynthesis pathway in C. album. In addition, 285 differentially expressed transcription factors (TFs) continuously down-regulated in four developmental periods of C. album fruit, which may indicate their potential role in the response to polyphenol metabolism and phenylpropanoid biosynthesis pathways. This report will help us understand polyphenol biosynthesis’s functions and metabolic mechanism in C. album. The transcriptome data provide a valuable resource for genetic and genomics research. They will facilitate future work exploiting C. album and other fruits used as medicine and food.

The composition of phenolic compounds in Chinese olive (Canarium album L.) cultivars and their contribution to the anti-inflammatory properties of the cultivars.

This study aimed to explore the phenolic compounds (PCs) present in three Chinese olive (Canarium album L.) cultivars and the contribution of these PCs to the anti-inflammatory activities of the cultivars. Ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap/mass spectrometry (UPLC-Q-Exactive/MS) was used to identify and quantify the PCs present in three Chinese olive cultivars, "Na zhong," "Tan xiang," and "Xiang zhong". 2,2-diphenyl-1-picrylhydrazyl (DPPH); 2,2'-azinobis (3-ethylbenzothiazoline 6-sulfonate) (ABTS); and oxygen radical absorption capacity (ORAC) assays were used to assess the antioxidant activities of the PCs. Furthermore, we analyzed the anti-inflammatory action of these PCs using lipopolysaccharide (LPS)-induced RAW264.7 cells. A total of 44 PCs were identified in the three cultivars. Of these, 17 PCs were previously unidentified in Chinese olive. Among the cultivars, the free phenolics (FPs) of "Tan xiang" showed the strongest antioxidant activity. All cultivars have shown significant inhibition of TNF-α and IL-6 production. Clustering correlation analysis showed galloyl-bis-HHDP-glucose and paeonol have significant anti-inflammatory ability in FPs. Quininic, galloylquinic acid, 4-hydroxycinnamic acid and gallic acid hexoside have shown significant inhibition of IL-6 production in BPs. Furthermore, gallic acid, catechin, syringic acid, and nobiletin exhibit negative correlation in FPs and positive correlation in BPs of cytokine production, while corilagin and methyl ellagic acid pentoside exhibited opposite correlation. In summary, this study contributed to the literature on PCs in Chinese olives and the potential health benefits of FPs and BPs.

Alleviation of chilling injury in cold-stored Chinese olive (Canarium album Lour.) fruit by γ-aminobutyric acid treatment in relation to ROS metabolism

Chinese olives are susceptible to chilling injury (CI) during refrigeration. Exploring economical and convenient approaches to suppress CI development is important for preserving fruit quality and prolonging postharvest shelf-life of Chinese olives. In this study, the effects of 1.0 mM γ-aminobutyric acid (GABA) treatment on CI development and ROS metabolism in cold-stored Chinese olives at 2 °C for 100 d were evaluated. The results demonstrated that, compared to control Chinese olives, GABA treatment observably alleviated CI development, remarkably suppressed the increased CI index, O2−. production rate, and MDA amount, but retained higher SOD, CAT and APX activities, higher values of GSH and AsA, higher abilities of scavenging DPPH radical, and higher reducing power. On the last day of storage (day 100), CI index, O2−. production rate, and MDA content in control Chinese olives were 2.06-, 1.28, 1.48-fold higher compared with those of GABA-treated fruits. In contract, SOD, CAT and APX activities in GABA-treated fruits were 1.54-, 3.24, 1.57-fold higher than in that of control Chinese olives. The GSH and AsA contents, DPPH scavenging ability and reducing power were 64.7%, 128.4%, 51.8% and 35.0% higher in GABA-treated olives, as compared to control fruits. Together, these findings indicate that 1.0 mM GABA shows a potential application in improving antioxidant capacity and alleviating CI development of Chinese olives during cold storage.

Analysis and identification of phenolic compounds with antiproliferative activity from Chinese olive (Canarium album L.) fruit extract by HPLC-DAD-SPE-TT-NMR.

Chinese olives (Canarium album L.) are rich in phenolic compounds, exhibiting a broad spectrum of potential clinical applications. This study is the first report on the isolation and elucidation of bioactive compounds with high antiproliferative activity from the ethyl acetate fraction of a Chinese olive fruit methanolic extract (CO-EtOAc). We used the WST-1 assay to determine which subfractions of CO-EtOAc had significant antiproliferative activity using the murine colon cancer cell line CT26. Subsequently, the functional compounds were characterized by the hyphenated technique and high-performance liquid chromatography-diode array detector-solid phase extraction-transfer tube-nuclear magnetic resonance (HPLC-DAD-SPE-TT-NMR). Thirteen phenolic constituents were identified from the antiproliferation-enhancing subfractions of CO-EtOAc, including two new compounds, 2,4-didehydrochebulic acid 1,7-dimethyl ester (5) and 1-hydroxybrevifolin (7), which were further purified and found to exhibit marked antiproliferative activity. Chebulic acid dimethyl ester (2), which was isolated from C. album for the first time, also possessed antiproliferative activity.

Chinese olive (Canarium album Rauesch.): a critical review on its nutritional value, phytochemical composition, health benefits, and practical applications

Chinese olive is a popular fruit with a long history of cultivation and consumption. As a fruit with edible, nutritional, and even medicinal value, the Chinese olive has attracted increased interest from both nutrition researchers and health-conscious consumers. Chinese olive is a rich nutrient source, including essential and non-essential amino acids, various fatty acids, organic acids, vitamins, microelements, and high-quality dietary fibers. It is also an important natural source of phytochemicals such as phenolic acids, flavonoids, phenylpropanoids, and other bioactive compounds. The nutritional and phytochemical compounds obtained from the Chinese olive exhibit unique and potent biological activities, explaining its various benefits to human health, including anti-Helicobacter pylori, anti-influenza, anti-diabetes, anti-inflammatory, anti-tumor effects, among others. This review focuses on recent studies on Chinese olives and aims to summarize the major advances in their nutritional value, phytochemical composition, health benefits, and practical applications. It provides a reference for further research on Chinese olives and their properties and the development of novel functional products.

Respiratory and energy metabolisms participate in the disease occurrence of fresh Chinese olive caused by Pestalotiopsis microspora

Pestalotiopsis microspora (P. microspore) is the primary pathogen causing postharvest rot and spoilage in Chinese olive (Canarium album L.). This study investigated P. microspore-induced disease development in postharvest Chinese olives in relation to respiratory and energy metabolism. Results suggested that P. microspore-inoculated Chinese olives had higher fruit disease index, fruit disease diameter, and fruit respiration rate, but a lower energy charge. Furthermore, P. microspore-inoculated Chinese olives displayed higher respiratory metabolism-related enzymes (RMREs) activities, higher levels of NAD(H), and lower levels of NADP(H). Additionally, P. microspore-inoculated Chinese olives had lower ATPase activities, as well as lower ATP and ADP contents but higher AMP content. These findings suggest that P. microspore infection exacerbates disease development in postharvest Chinese olives by increasing respiration metabolism and causing energy deficiency.

Evidence that Chinese white olive (Canarium album (Lour.) DC.) fruits are solids of revolution

ABSTRACT Although many fruit geometries resemble a solid of revolution, this assumption has rarely been rigorously examined. To test this assumption, 574 fruits of Canarium album (Lour.) DC. which appear to have an ellipsoidal shape, were examined to determine the validity of a general avian-based egg-shape equation, referred to as the explicit Preston equation (EPE). The assumption that the C. album fruit geometry is a solid of revolution is tested by applying the volume formula for a solid of revolution using the EPE. The goodness of fit of the EPE was assessed using the adjusted root-mean-square error (RMSEadj). The relationship between the observed volume (V obs) of each fruit, as measured by water displacement in a graduated cylinder, and the predicted volumes (V pre) based on the EPE was also evaluated using the equation V pre = slope * V obs. All the RMSEadj values were smaller than 0.05, which demonstrated the validity of the EPE based on C. album fruit profiles. The 95% confidence interval of the slope of V pre vs. V obs included 1.0, indicating that there was no significant difference between V pre and V obs. The data confirm that C. album fruits are solids of revolution. This study provides a new approach for calculating the volume and surface area of geometrically similar fruits, which can be extended to other species with similar fruit geometries to further explore the ontogeny and evolution of angiosperm reproductive organs.

Identification of Scoparone from Chinese Olive Fruit as a Modulator of Macrophage Polarization

Chinese olive (Canarium album L.) has been highlighted for its remarkable health benefits. We previously showed that the ethyl acetate fraction of Chinese olive (COE) is an effective anti-inflammatory agent. In this study, we used a luciferase-based RAW 264.7 cell platform to detect the transcriptional activity of NF-κB, a key mediator of inflammation, and the promoter activity of its downstream target, COX-2. Through functional-oriented screening using these platforms, we further divided COE into several subfractions. Subsequently, we used silica gel column chromatography for purification, and the active compounds were separated and isolated by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The structure of the resulting compound with high anti-inflammatory activity was then identified as scoparone. Our results showed that scoparone not only inhibited lipopolysaccharide (LPS)-induced secretion of nitric oxide and suppressed M1 macrophage markers (iNOS, Il-6, Ccl2, and Tnf-α) but also markedly decreased the production of pro-inflammatory cytokines (IL-6, CCL2, and TNF-α). Treatment with scoparone significantly reduced the protein level of TNF-α in LPS-treated bone-marrow-derived macrophages (BMDMs). In addition, scoparone promoted macrophages toward an M2 anti-inflammatory phenotype, as determined by the significantly increased gene expression of M2 macrophage markers (Arg1, Ym1, Mrc1, Il-10, and Cd206) and the protein level of Arg1. This study indicates that COE fruit has high therapeutic potential for various inflammatory diseases as a result of switching the macrophage phenotype from pro-inflammatory M1 to anti-inflammatory M2.

Accumulation of Polyphenolics and Differential Expression of Genes Related to Shikimate Pathway during Fruit Development and Maturation of Chinese Olive (Canarium album)

Phenolics in the Chinese olive (Canarium album (Lour.) Raeusch) fruit significantly affect its flavor and quality. The shikimate pathway is a bridge connecting primary metabolism and secondary metabolism through which fixed carbon can be transformed into phenolics. In this study, we aimed to reveal the relationship between the shikimate pathway and phenolic compound biosynthesis. Three Chinese olive fruits (cv. Tanxiang (TX), Changying (CY) and Lingfeng (LF)) with distinct flavor were utilized as materials. The results of this study showed that the synthesis and accumulation of quinate and gallate were active in the Chinese olive fruit. The accumulation amount of phenolic compounds was significantly different among the three cultivars. TX contained the highest content of ellagate, (iso)corilagin, conjugated quercetin and conjugated kaempferol; CY contained the highest content of conjugated luteolin; and LF contained the lowest content of ellagate, conjugated gallate, hyperin, conjugated quercetin, conjugated kaempferol and conjugated luteolin during fruit development. The expression of 3-dehydroquinate/shikimate dehydrogenase gene-4 (DHD/SDH-4), 3-dehydroquinate synthase gene (DHQS), chorismate synthase gene (CS) and Chorismate mutase gene-1 (CM-1) and shikimate content increased with the maturing of fruit. The gene 3-Deoxy-D-arabino-heptulosonate-7-phosphate synthase gene-1 (DAHPS-1) was most expressed in TX, while barely expressed in LF during fruit development. The expression of CM-1 was highest in CY. Chorismate mutase gene-2 (CM-2) expression was higher in TX and CY during late fruit development. The cultivars with higher expression of DAHPS-1 and Chorismate mutase genes (CMs) accumulated more phenolic compounds in fruit. DAHPS-1 and CMs are proposed as key genes for polyphenolic synthesis in the Chinese olive fruit. These results proved that shikimate metabolism had a positive effect on the phenols’ synthesis. Our study provides new insight into the regulatory mechanism of the biosynthesis and accumulation of phenolic compounds in the fruit of Chinese olive.

Urolithin M5 from the Leaves of Canarium album (Lour.) DC. Inhibits Influenza Virus by Targeting Neuraminidase.

Ganlanye (GLY), the leaf of Canarium album (Lour.) DC., is a traditional Chinese medicinal herb for warm disease treatment. We found that its aqueous extract could inhibit the influenza A virus. To find and characterize anti-influenza virus phytochemicals from GLY, we performed (1) bioassay-guided isolation, (2) a cell and animal assay, and (3) a mechanism study. Bioassay-guided isolation was used to identify the effective components. Influenza virus-infected MDCK cell and BALB/c mouse models were employed to evaluate the anti-influenza virus activities. A MUNANA assay was performed to find the NA inhibitory effect. As a result, urolithin M5 was obtained from the crude extract of GLY. It inhibited influenza virus activities in vitro and in vivo by suppressing the viral NA activity. In the MDCK cell model, urolithin M5 could inhibit an oseltamivir-resistant strain. In a PR8-infected mouse model, 200 mg/kg/d urolithin M5 protected 50% of mice from death and improved lung edema conditions. GLY was recorded as a major traditional herb for warm disease treatment. Our study identified GLY as a potent anti-influenza herb and showed urolithin M5 as the active component. We first report the in vivo activity of urolithin M5 and support the anti-influenza application of GLY.

Blending Canarium Flavor (Canarium album L.) for Soft Candy from Natural Materials in Vietnam

Aim and Objectives: The aim of this study is to create Canarium flavor with the main ingredient (Body note) being Canarium album (Lour.) Raeusch essential oil and natural essential oils found in Vietnam for soft candy product.
 Materials and Methods: All the materials for making the Canarium flavor were from natural sources in Vietnam. Materials for making soft candy such as gelatin, sugar, and lemon juice were purchased in Vietnam market.
 Flavor assessment experiment was conducted by olfactory. The created flavor of Canarium was tested on soft candy with 0.3% by weight.
 Results: After the experiment, the flavors SC1, SC2 and SC3 having the ideal taste and smell for soft candy, were selected. The structure of flavors SC1, SC2 and SC3 included Grassy note, Green note, Fruity note, Woody note, Spicy note, Floral note, Sweete note and Spicy note. Flavors SC1, SC2 and SC3 had the same composition of 80% by weight, of which the main ingredient was Canarium oil (Canarium album L.) accounting for 50% by weight.
 Conclusions: The flavors SC1, SC2 and SC3 were created from natural materials in Vietnam for soft candy product. Flavors SC1 and SC2, SC3 had natural, gentle and attractive scent. Flavor SC1 featured a Canarium odor and a Lemon leaf flavor. Flavor SC2 contained the characteristic aroma of Canarium and the sweet-spicy flavor of Cinnamon bark. Flavor SC3 was made up of Canarium odor and the spicy-hot flavor of ginger. The flavor and taste of SC1, SC2 and SC3 were very suitable for soft candy.

Integrated Metabolomic and Transcriptomic Analysis Reveals Differential Flavonoid Accumulation and Its Underlying Mechanism in Fruits of Distinct Canarium album Cultivars.

Canarium album fruit has great potential to be consumed as a raw material not only for food but also medicine. The diverse active metabolites composition and content of C. album fruits greatly affect their pharmacological effects. However, up to now, there has been no report on the global metabolome differences among fruits from distinct C. album cultivars. In our present study, by using non-targeted metabolomics techniques, we identified 87 DAMs (differentially accumulated metabolites) including 17 types of flavonoids from fruits of four different C. album cultivars. KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway enrichment analysis revealed that the flavone and flavonol biosynthesis- and flavonoid biosynthesis-related DAMs were major factors determining their metabolome differences. Comparative transcriptomic analysis revealed that 15 KEGG pathways were significantly enriched by genes of the identified 3655 DEGs (differentially expressed genes) among different C. album cultivars. Consistent with the metabolome data, flavonoid biosynthesis-related DEGs, including eight key structural genes (such as FLS, CCoAOMT, CHI, C4H, DFR, LAR, and C3′H, etc.) and several regulatory transcription factor (TF) genes (including 32 MYBs and 34 bHLHs, etc.), were found to be significantly enriched (p < 0.01). Our study indicated that the differential expression of flavonoid biosynthesis-related genes and accumulation of flavonoids played dominant roles in the various metabolome compositions of fruits from different C. album cultivars.

Integrated SRNA-Seq and RNA-Seq Analysis Reveals the Regulatory Roles of miRNAs in the Low-Temperature Responses of Canarium album

Chinese olive (Canarium album), a characteristic fruit tree in tropical and subtropical areas, suffers greatly from low-temperature stress (LTS). The regulatory roles of microRNA (miRNA) in plant LTS responses have been confirmed in many plant species but not in C. album. In this study, a cold-tolerant cultivar ‘Rui’an 3′ (RA) and a susceptible cultivar ‘Qinglan 1’ (QL) treated at 25 °C (control, CK) and −3 °C (cold temperature treatment, CT) were subjected to small RNA (sRNA) and transcriptome sequencing for the exploration of the cold responses of C. album. Comparative sRNA sequencing analysis identified much fewer LTS-responsive, differentially expressed miRNAs (DEMs) in RA (4 DEMs) than in QL (23 DEMs). Cal-miR482-22 was found to be specifically induced by LTS in RA. Cal-miR397-3 was upregulated, while cal-miR398_2-3 and cal-undef-190 were downregulated after LTS only in QL. However, when compared with QL, a higher basic expression of cal-miR397-3, and lower expression of cal-miR398_2-3 and cal-undef-190 were found in RA, suggesting that they may contribute to the cold tolerance of RA. Comparative transcriptome analysis showed that the number of LTS-responsive differentially expressed genes (DEGs) identified in QL was larger than that in RA, and some DEGs were also predicted as the target genes of the identified DEMs, forming multiple differentially expressed miRNA–target gene pairs, such as cal-miR397-3_laccase 2, 4, 17, cal-miR482-22_suppressor of npr1-1, etc. Quantitative real time PCR results showed that the expression changes of DEGs and DEMs in different samples were generally consistent with the sequencing results. Our study indicated that the basic expression levels of some miRNAs (especially the cal-miR397-3, cal-miR398_2-3, and cal-miR482-22), and their target genes contribute greatly to the cold-tolerance characteristics of C. album. Our study is helpful for understanding the roles of miRNAs in the cold resistance and responses of C. album.