Research progress in the phytochemistry and biology of Ilex pharmaceutical resources

Screening candidate genes for fruit size based on QTL-seq in Chinese jujube

Introduction

Fruit size is an important economic trait affecting jujube fruit quality, which has always been the focus of marker-assisted breeding of jujube traits. However, despite a large number of studies have been carried out, the mechanism and key genes regulating jujube fruit size are mostly unknown.

Methods

In this study, we used a new analysis method Quantitative Trait Loci sequencing (QTL-seq) (bulked segregant analysis) to screen the parents 'Yuhong' and 'Jiaocheng 5' with significant phenotypic differences and mixed offspring group with extreme traits of large fruit and small fruit, respectively, and, then, DNA mixed pool sequencing was carried out to further shortening the QTL candidate interval for fruit size trait and excavated candidate genes for controlling fruit size.

Results

The candidate intervals related to jujube fruit size were mainly located on chromosomes 1, 5, and 10, and the frequency of chromosome 1 was the highest. Based on the QTL-seq results, the annotation results of ANNOVAR were extracted from 424 SNPs (single-nucleotide polymorphisms) and 164 InDels (insertion-deletion), from which 40 candidate genes were selected, and 37 annotated candidate genes were found in the jujube genome. Four genes (LOC107428904, LOC107415626, LOC125420708, and LOC107418290) that are associated with fruit size growth and development were identified by functional annotation of the genes in NCBI (National Center for Biotechnology Information). The genes can provide a basis for further exploration and identification on genes regulating jujube fruit size.

Discussion

In summary, the data obtained in this study revealed that QTL intervals and candidate genes for fruit size at the genomic level provide valuable resources for future functional studies and jujube breeding.

A systematic review: Botany, phytochemistry, traditional uses, pharmacology, toxicology, quality control and pharmacokinetics of Ilex rotunda Thunb

ETHNOPHARMACOLOGICAL RELEVANCE

Ilex rotunda Thunb. (I. rotunda) is an Ilex species of Aquifoliaceae, widely distributed in East Asia. Its dried bark is commonly used as a medicinal part in the field of traditional Chinese medicine (TCM), named Ilicis Rotundae Cortex. This medicinal plant is commonly used for clearing heat and removing toxin, draining dampness and relieving pain in TCM to treat tonsillitis, acute gastroenteritis, gastric and duodenal ulcer, rheumatism, traumatic injury, and so on. It also has significant development value on lipid-lowering, hepatoprotection and anti-inflammation, but the potential mechanism needs to be further explored.

AIM OF THE REVIEW

More and more medicinal substances are being discovered in I. rotunda with multiple biological activities, which help to advance the ethno-pharmacological research in I. rotunda. However, to date there is a lack of a systematic summary of research progress on I. rotunda. This review aims to provide a critical summary of the current studies on I. rotunda. The progress in research on botany, phytochemistry, traditional uses, pharmacology, toxicology, quality control and pharmacokinetics of the plant is discussed. It hopes to provide useful references and guidance for the future directions of research on I. rotunda.

MATERIALS AND METHODS

Studies of I. rotunda were collected via Google Scholar and Baidu Scholar, PubMed, ScienceDirect, SciFinder, Web of Science, China National Knowledge Infrastructure (CNKI), WANFANG DATA and libraries. Some local books, official websites, PhD or MS's dissertations were also included. The literature cited in this review covered the period from 1956 to January 2022.

RESULTS

Analysis of the literature indicates that I. rotunda is a potentially valuable herbal medicine for the therapeutic of various diseases. To date, 120 compounds were found and identified in I. rotunda, mainly including triterpenoids, phenylpropanoids, etc. Modern pharmacological studies also found that the plant has the activities of protecting the cardiovascular system, lowering lipids and protecting the liver, as well as being an anti-inflammatory, anti-tumor and antibacterial.

CONCLUSIONS

This review summarizes the results from current studies of I. rotunda. However, the current explanation seems insufficient and unsatisfactory, in terms of the relationships between the traditional uses and the modern pharmacological activities, the mechanisms and the material basis. Thus, a critical and comprehensive evaluation is necessary to explore its future research prospects and development direction.

Assessing Phenotypic Variability in Some Eastern European Insular Populations of the Climatic Relict Ilex aquifolium L

Through its natural or cultivated insular population distribution, Ilex aquifolium L. is a paramount species which is exceptionally suitable for studying phenotypic variability and plasticity through the assessment of morphological, physiological, biochemical and genomic features with respect to acclimation and/or adaptation efficiency. The current study is focused on four insular populations of Ilex aquifolium from Eastern Europe (i.e., in Romania, Hungary, Serbia and Bulgaria), and presents an initial evaluation of phenotypic variability in order to conclude our research on phylogenetic relationships and phytochemical profiles, including several descriptive and quantitative morphological traits. Taken together, the data from different methods in this paper indicate that the Bulgarian and Romanian populations can be distinguished from each other and from Serbian and Hungarian populations, while the latter show a higher level of resemblance with regards to their quantitative morphological traits. It is likely that these morphological traits are determined through some quantitative trait loci implicated in stress responses generated by light, temperature, soil water, soil fertility and salinity conditions that will need to be analysed in terms of their physiological, genomic and metabolomics traits in future studies.

Anatomical Characterization, HPLC Analysis, and Biological Activities of Ilex dipyrena

Ilex dipyrena Wall (Aquifoliaceae), is a traditional medicinal plant abundantly found in India and Pakistan. In the current research work, initially, the anatomical characteristics were recorded through microscopic examination of selected plant parts, such as leaf, petiole, and midrib. Then, the quantitative phytochemical screening was performed using standard tests reported in literature. The whole-plant powdered sample was then soaked in methanol to obtain crude extract, which was then fractionated into solvents of different polarities to obtain ethyl acetate, chloroform, butanol, hexane, and aqueous extracts. The phytochemical composition of the crude ethyl acetate and chloroform extracts (being the most active fractions) was then confirmed through HPLC analyses, where the possible phytochemical present were predicted through comparison of retention time of a given compound peak with the available standards. The extracts were also evaluated for their in vitro antioxidant and ani-lipoxygenase potentials using standard methods. The microscopic examination revealed the presence of anomocytic type stomata on the abaxial side of the leaf as well as unicellular trichrome and calcium oxalate druses crystals in the midrib and petiole, with a single, centered U-shaped collateral arterial bundle, which was directed toward the adaxial and the phloem toward the abaxial sides of the selected plant parts, respectively. Almost all tested representative groups of phytochemicals and essential minerals were detected in the selected plant, whereas five possible phytochemicals were confirmed in crude and chloroform extract and seven in ethyl acetate fraction. As antioxidant, chloroform fraction was more potent, which exhibited an IC₅₀ value of 64.99, 69.15, and 268.52 µg/mL, determined through DPPH, ABTS, and FRAP assays. Ethyl acetate extract was also equally potent against the tested free radicals. Chloroform and ethyl acetate extracts were also potent against lipoxygenase, with IC₅₀ value of 75.99 and 106.11 µg/mL, respectively. Based on the results of biological studies, Ilex dipyrena was found to good inhibitor of free radicals and lipoxygenase that could be further investigated to isolate compounds of medicinal importance.

Biological Potential and Chemical Profile of European Varieties of Ilex

Plants of the genus Ilex are widespread throughout the world, with its best-known representative being Ilex paraguraiensis from South America. The European species Ilex aquifolium shows similarities in its terpenoid, sugar and phenolic acid profiles. Using aqueous extracts of Ilex aquifolium as a supplement in Wistar rats showed that, despite the lack of caffeine, it had strong hypocholesterolemic effects. In addition, a reduction in oxidative lipid degradation and a decrease in hepatic steatosis in histopathological studies were observed. The results of this study suggest that extracts from the European species Ilex aquifolium may have potential as an alternative treatment for hyperlipidemia.

Composition and Antimicrobial Activity of Ilex Leaves Water Extracts

Plants from the Ilex genus are known for properties such as antimicrobial and anti-inflammatory activity, can act as antiobesity agents and thus can be helpful in medicine. Some holly species, such as Ilex paraguariensis (widely known in the form of popular beverage: yerba mate), have been investigated, while others have been partially researched or remain unknown. Therefore, we performed qualitative and quantitative phytochemical analyses and screened antimicrobial properties of lesser-studied species (I. aquifolium L., I. aquifolium ‘Argentea Marginata’ and I. × meserveae ‘Blue Angel’). I. paraguariensis was used as a standard species for comparison purposes. Investigations were performed on water extracts due to their expected activity and composition. Antimicrobial research included evaluating minimal inhibitory, bactericidal (Staphylococcus aureus and Escherichia coli) and fungicidal concentration (Candida albicans, Alternaria alternata, Fusarium oxysporum, and Aspergillus niger) of extracts. The influence of the extracts on the production, eradication, and viability of bacterial biofilms was also analysed. It was established that Ilex paraguariensis possesses the richest profile of hydroxycinnamic acids derivatives in terms of component concentration and diversity. Ilex spp., especially I. × meserveae, contain a slightly higher amount of flavonoids and more different flavonoid derivatives than I. paraguariensis. However, the strongest antibacterial activity was shown by I. aquifolium L. and its cultivar ‘Argentea Marginata’ in terms of minimal inhibitory, bactericidal and fungicidal concentration, and biofilm assays. Extracts from both species significantly reduced the biofilm viability of S. aureus as well, which may be of use in the production of multicomponent lavaseptics, antiseptics, diuretics (supporting urinary tract infection therapy) and, due to their action on fungi, additives to growth media for specific fungi. The significant content of saponins enables Ilex extracts to be used as natural emulsifiers, for example, in cosmetics. Moreover, relatively high chlorogenic acid and rutin content may suggest use of Ilex spp. to treat obesity, digestive problems, in chemoprevention, and as preservatives in the food industry.

In Vitro Free Radical Scavenging Properties and Anti-Inflammatory Activity of Ilex paraguariensis (Maté) and the Ability of Its Major Chemical Markers to Inhibit the Production of Proinflammatory Mediators

Ilex paraguariensis A. St. Hil. (Aquifoliaceae), popularly known as “yerba mate,” has great economic and social significance for the population of Southern Latin America. This study was conducted (1) to investigate the phytochemical composition of four different standardized extracts, (2) to investigate its free radical scavenging properties, and (3) to investigate the anti-inflammatory action of I. paraguariensis and its major chemical markers. The chemical profile was achieved by Folin-Ciocalteu, by LC/DAD, and by LC/MS assays, while the antioxidant and anti-inflammatory properties were investigated, respectively, by DPPH assay and by inhibition of nitric oxide (Griess reaction) and TNF-α (ELISA). Our results demonstrated that the IA (aqueous infusion extract) showed higher amounts of total phenolic contents (266.62 ± 10.85 mg CAE·g⁻¹ DE), the highest amounts of all six chemical markers (theobromine, 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 3-O-caffeoylquinic acid, caffeine, and rutin), and stronger antioxidant activity (EC₅₀ = 54.4 ± 5.14 μg · mL⁻¹). The IA extract also showed the lowest inhibition of NOx secretion (50.10 ± 8.97%) as well as inhibition of TNF-α (83.33 ± 4.01%). Regarding the chemical markers, all compounds showed strong inhibition of NOx secretion, especially theobromine, which was 200x more potent than dexamethasone. Furthermore, TNF-α secretion was also significantly decreased by THEO at 0.033 μM (22.15 ± 6.49%), NCA at 1.97 μM (27.46 ± 3.98%), CCA at 0.35 μM (39.76 ± 5.73%), CGA at 0.56 μM (23.58 ± 5.79%), CAF at 0.52 μM (26.45 ± 5.34%), and RUT at 0.16 μM (40.18 ± 3.70%). Our results suggest that I. paraguariensis and its major chemical markers have strong free radical scavenging properties as well as showed important anti-inflammatory activity and that these compounds in a plant extract may work based on several different mechanisms synergistically, resulting in moderating the immune system.

Four New Triterpenoid Saponins from the Root of Ilex centrochinensis

One new siaresinolic acid saponin (1) and three new rotundic acid saponins (2-4) were isolated from the roots of Ilex centrochinensis. Their structures were confirmed by detailed analysis of standard spectroscopic data (IR, MS, 1D and 2D NMR). Compounds 1-4 exhibited anti-inflammatory activity by inhibiting nitric oxide production in a lipopolysaccharide-induced RAW264.7 cell inflammatory model. However, they showed no significant lipid-lowering activity against the production of triglycerides in the lipid-accumulation model of HepG2 cells induced by oleic acid.

Safety evaluation and hypolipidemic effect of aqueous-ethanol and hot-water extracts from E Se tea in rats

E Se tea, processed by the fresh leaves of Malus toringoides (Rehd.) Hughes, is a traditional herbal tea with various human benefits. The present study was aimed to evaluate the toxicity and hypolipidemic effect of aqueous-ethanol extract (EE) and hot-water extract (WE) from E Se tea. Eight main chemical constituents in EE and WE were respectively identified and quantified by UHPLC-HRMS/MS. EE is rich in TPC and TFC, while WE had higher TPS content. Both EE and WE exhibited strong antioxidant activity with no significant difference. The acute toxicity study revealed that the LD₅₀ values were higher than 5000 mg/kg, while both WE and EE had no significant adverse effect in rats by subacute toxicity assay. However, the triglyceride (TG) content in experiment groups (male) and highest doses groups (female) significantly decreased. Furthermore, the hypolipidemic effect of WE and EE were performed on high fat diet induced hyperlipidemic rats. The result exhibited that either WE or EE could effectively regulate lipid droplet accumulation in liver, and reduce the adipocyte size. These results demonstrated that these two extracts from E Se tea could be regarded as a potential functional dietary supplement in preventing and treating diet induced metabolic diseases.

Evaluation of antinociceptive activity of Ilex dipyrena Wall. in mice

BACKGROUND

In order to find a new natural resource for pain-relief, the analgesic effects of Ilex dipyrena crude extract, fractions, and subfractions were evaluated in in-vivo mouse models with possible mechanism of action.

METHODS

Analgesic effects of crude extract (100 and 200 mg/kg body weight), fractions and subfractions (75 mg/kg body weight) were screened using heat-induced (tail-immersion and hot plate test) and chemical-induced (formalin and acetic acid) nociception models in mice. The samples were also tested for the elucidation of a possible mechanism through opioidergic and GABAergic systems.

RESULTS

The administration of crude extract, fractions and subfractions produced analgesic responses in acetic acid, formalin, tail immersion, and hot plate model for pain similar to those obtained with the standard. Naloxone antagonized the antinociceptive effects of the tested samples, whereas bicuculline showed partial inhibition. Considering the analgesic response, crude extract, fractions, and subfractions demonstrated promising inhibitory activity against all test models for pain, which was further supported by the possible involvement of opioidergic and GABAergic systems.

CONCLUSION

The results suggest that this plant may be useful in the development of new analgesic drugs. Further research with regard to the isolation of bioactive compounds is required to verify these findings.

Network Pharmacology Study to Interpret Signaling Pathways of Ilex cornuta Leaves against Obesity

Ilex cornuta Leaves (ICLs) are a representative and traditional prescription for controlling obesity. Nevertheless, the corresponding therapeutic compounds and related pharmacological mechanisms of such medication remain undocumented. The compounds from ICLs were identified by gas chromatography-mass spectrum (GC-MS), and SwissADME confirmed their physicochemical properties. Next, the target proteins related to compounds or obesity-associated proteins were retrieved from public databases. RPackage constructed the protein–protein interaction (PPI) network, a bubble chart, and signaling pathways–target proteins–compounds (STC) network. Lastly, a molecular docking test (MDT) was performed to evaluate the affinity between target proteins and ligands from ICLs. GC-MS detected a total of 51 compounds from ICLs. The public databases identified 219 target proteins associated with selective compounds, 3028 obesity-related target proteins, and 118 overlapping target proteins. Moreover, the STC network revealed 42 target proteins, 22 signaling pathways, and 39 compounds, which were viewed to be remedially significant. The NOD-like receptor (NLR) signaling pathway was considered a key signaling pathway from the bubble chart. In parallel, the MDT identified three target proteins (IL6, MAPK1, and CASP1) on the NLR signaling pathway and four compounds against obesity. Overall, four compounds from ICLs might show anti-obesity synergistic efficacy by inactivating the NLR signaling pathway.

The complete plastid genome sequence of Ilex suaveolens (H. Lév.) Loes, the most abundant medicinal holly in Mount Huangshan

Holly (Ilex L.) is a woody dioecious genus cultivated as pharmaceutical, ornamentals, and industrial materials. Ilex suaveolens (H. Lév.) Loes is an endemic medicinal holly with a predominant distribution in Mount Huangshan, China. In the present work, the complete plastid genome of I. suaveolens was de novo sequenced by high-throughput sequencing technology. The newly-assembled plastid genome holds 37.6% of the overall GC content and a length of 157,857 bp, comprising a large single-copy (LSC, 87,255 bp), a small single-copy (SSC, 18,398 bp), and a pair of inverted repeat (IRs, 26,102 bp) regions. The plastid genome annotation suggested the presence of a total of 89 protein-encoding genes, 37 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. The plastome-mediated phylogenetic topology revealed that I. suaveolens clustered together with I. szechwanenesis and I. viridis in the same clade, and a strong relationship between clades and biogeography was found. These data contribute to the understanding of genetic diversity and conservation study of Ilex in Mount Huangshan.

Chemical Composition, Bioactivity and Safety Aspects of Kuding Tea-From Beverage to Herbal Extract

Kuding tea (KT) is a bitter-tasting herbal tea that has been commonly used in traditional Chinese medicine (TCM). The large-leaved Ku-Ding-Cha (Aquifoliaceae) is composed of its representative species Ilex latifolia Thunb and Ilex kudingcha C.J. Tseng. Because of its potential lipid-lowering, body weight-reducing and blood-glucose-lowering properties, KT has increasingly been recognised for its importance over the past several decades. KT is no longer used only as a beverage, and various extraction methods have been applied to obtain aqueous and ethanolic KT extracts (KTE) or their fractions, which could potentially be used as dietary supplements. The major bioactive components of KT are triterpene saponins and polyphenols, but the composition of KT differs substantially between and among the different KT species. This in turn might affect the physiological effects of KT. KT exhibits antiobesity properties, possibly partly by affecting the intestinal microbiota. In addition, KT may mediate putative antioxidative, anti-inflammatory and anticancer activities. However, there is evidence that high KTE supplementation can adversely affect liver metabolism. The physiological relevance of KT in humans remains rather unclear since the potential health benefits of KT and its constituents reviewed here are mainly derived on the basis of in vitro and animal studies.

Comparative Survey of Morphological Variations and Plastid Genome Sequencing Reveals Phylogenetic Divergence between Four Endemic Ilex Species

Holly (Ilex L.), from the monogeneric Aquifoliaceae, is a woody dioecious genus cultivated as pharmaceutical and culinary plants, ornamentals, and industrial materials. With distinctive leaf morphology and growth habitats, but uniform reproductive organs (flowers and fruits), the evolutionary relationships of Ilex remain an enigma. To date, few contrast analyses have been conducted on morphology and molecular patterns in Ilex. Here, the different phenotypic traits of four endemic Ilex species (I. latifolia, I. suaveolens, I. viridis, and I. micrococca) on Mount Huangshan, China, were surveyed through an anatomic assay and DNA image cytometry, showing the unspecified link between the examined morphology and the estimated nuclear genome size. Concurrently, the newly-assembled plastid genomes in four Ilex have lengths ranging from 157,601 bp to 157,857 bp, containing a large single-copy (LSC, 87,020–87,255 bp), a small single-copy (SSC, 18,394–18,434 bp), and a pair of inverted repeats (IRs, 26,065–26,102 bp) regions. The plastid genome annotation suggested the presence of numerable protein-encoding genes (89–95), transfer RNA (tRNA) genes (37–40), and ribosomal RNA (rRNA) genes (8). A comprehensive comparison of plastomes within eight Ilex implicated the conserved features in coding regions, but variability in the junctions of IRs/SSC and the divergent hotspot regions potentially used as the DNA marker. The Ilex topology of phylogenies revealed the incongruence with the traditional taxonomy, whereas it informed a strong association between clades and geographic distribution. Our work herein provided novel insight into the variations in the morphology and phylogeography in Aquifoliaceae. These data contribute to the understanding of genetic diversity and conservation in the medicinal Ilex of Mount Huangshan.

Complete chloroplast genome sequence and phylogenetic analysis of Ilex viridis Champ. ex Benth

Ilex viridis Champ. ex Benth. is domestic to southern China. In the present work, the complete chloroplast (cp) genome sequence of Ilex viridis was assembled and characterized by high-throughput sequencing analyses. The chloroplast genome was 157,701 bp in length, consisting of large single-copy (LSC) and small single-copy (SSC) regions of 87,177 bp and 18,394 bp, respectively, which were separated by a pair of 26,065 bp inverted repeat (IR) regions. The genome was predicted to contain 134 genes, including 89 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The overall GC content of the genome is 37.7%. The phylogenetic tree reconstructed using 13 chloroplast genomes reveals that I. viridis is mostly related to Ilex szechwanensis.

The complete plastid genome sequence of Ilex micrococca Maxim

Ilex micrococca Maxim. is a widely distributed species of Aquifoliaceae in Eastern Asia. In this study, the complete chloroplast (cp) genome sequence of I. micrococca was assembled and characterized by high-throughput sequencing data. The entire cp genome was 157,782 bp in length, containing a large single-copy region (LSC) of 87,200 bp, and a small single-copy region (SSC) of 18,434 bp, which were separated by a pair of 26,074 bp inverted repeat (IR) regions. The cp genome contained 134 genes, including 89 protein-coding genes, 37 tRNA genes, and 8 ribosomal RNA genes. Eighteen genes occur in double copies. The overall GC content is 37.6%. The phylogenetic tree reconstructed by 13 chloroplast genomes reveals that I. micrococca is most related with Ilex wilsonii. The complete cp genome provides valuable information for further phylogenetic and cp genetic engineering studies of this important Ilex species I. micrococca.

High Dietary Kuding Tea Extract Supplementation Induces Hepatic Xenobiotic-Metabolizing Enzymes-A 6-Week Feeding Study in Mice

Kuding tea (KT) is a traditional Chinese beverage rich in plant bioactives that may exhibit various health benefits. However, little is known about the safety of KT extract (KTE) when consumed long term at high doses as a dietary supplement. Therefore, in this study, we investigated aspects of the safety of KTE. Male C57BL/6 mice were fed a high-fat, high-fructose, Western-type diet (control) supplemented with either 12.88% γ-cyclodextrin (γCD), 7.12% KTE (comprising 0.15% ursolic acid, UA) encapsulated in 12.88% γCD (KTE-γCD), or 0.15% UA over a 6-week experimental period. The dietary treatments did not affect food intake, body weight or body composition. However, treatment with KTE-γCD, but not γCD and UA, increased liver weight and hepatic fat accumulation, which was accompanied by increased hepatic PPARγ and CD36 mRNA levels. KTE-γCD treatment elevated plasma cholesterol and CYP7A1 mRNA and protein levels compared to those in control mice. KTE-γCD substantially increased the mRNA and protein levels of hepatic CYP3A and GSTA1, which are central to the detoxification of drugs and xenobiotics. Furthermore, we observed a moderate elevation in hepatic CYP3A (5-fold change) and GSTA1 (1.7-fold change) mRNA levels in UA-fed mice. In vitro data collected in HepG2 cells indicated a dose-dependent increase in hepatic cytotoxicity in response to KTE treatment, which may have been partly mediated by UA. Overall, the present data may contribute to the safety assessment of KTE and suggest that KTE encapsulated in γCD affects liver fat storage and the hepatic phase I and phase II responses in mice.

Identification and Quantitation of Ursolic and Oleanolic Acids in Ilex aquifolium L. Leaf Extracts Using 13C and 1H-NMR Spectroscopy

Leaves of Ilex aquifolium L. have been used for their therapeutic properties. In previous studies, components contained in the leaves were first isolated by various chromatographic techniques. Then, quantitation of oleanolic and ursolic acids, which are responsible for the biological and therapeutic activities of the plant, was performed by HPLC, HPTLC, and somewhat by GC-MS. Our objective was to develop a simple method that allows the identification of compounds contained in the leaves of Corsican I. aquifolium and to quantify ursolic and oleanolic acids. Leaves were successively extracted with hexane and dichloromethane. The extracts were chromatographed on silica gel and the fractions of column chromatography submitted to 13C-NMR analysis, following a computerized method developed in the laboratory. 13C-NMR allowed the identification of various triterpenes including ursolic acid and oleanolic acid. Quantitation of both acids was achieved, for the first time, by 1H-NMR after validation of the method (accuracy, precision, linearity, limit of detection and limit of quantitation). Ursolic and oleanolic acids accounted for 55.3% and 20.8% of the dichloromethane extract, respectively. This represents 1.3% and 0.5% of the mass of dried leaves. 1H-NMR spectroscopy appeared as a powerful tool for a rapid quantitation of biologically active compounds from I. aquifolium.

LC-MS Metabolomics and Chemotaxonomy of Caffeine-Containing Holly ( Ilex) Species and Related Taxa in the Aquifoliaceae

Ilex species have been consumed traditionally as medicinal teas worldwide. Though the presence of caffeine has been reported in several species, little is known about secondary-metabolite diversity within and among these taxa. Leaf samples of Ilex guayusa, Ilex paraguariensis, and Ilex vomitoria were analyzed by liquid chromatography-mass spectrometry and comparative metabolite profiling with Ilex cassine and other Ilex species to identify chemotaxonomic markers, delimit species, and provide an assessment of chemodiversity. Purine alkaloids were detected and quantified in I. guayusa, I. paraguariensis, and I. vomitoria. Reports of caffeine for I. cassine were not corroborated, suggesting that I. vomitoria was the traditional source of the Native North American tea yaupon. The tetramethyluric acid, theacrine, was detected for the first time in the genus Ilex as a low-level chemotaxonomic marker in I. vomitoria samples. Chemotaxonomy and metabolomics support a close relationship for caffeine-containing Ilex species.

Antioxidant and anti-inflammatory properties of Ilex guayusa tea preparations: a comparison to Camellia sinensis teas

Ilex guayusa tea preparations are now commercially available as Runa tea. Little is known regarding the antioxidant and anti-inflammatory bioactivities of this tea. The I. guayusa teas had a total polyphenolic content between 54.39 and 67.23 mg GAE per g dry mass and peroxyl radical scavenging capacities between 1773.41 and 2019 μmol TE per g dry mass, nearly half of that for the Camellia sinensis teas. The I. guayusa teas afforded 60-80% protection from oxidative stress in the Caco-2 cellular antioxidant assay, comparable to the C. sinensis teas. The anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7 cells of I. guayusa teas was similarly comparable to the C. sinensis teas with nitric oxide production reduced by 10-30%. Major compounds identified by mass spectrometry were the phenolic mono- and dicaffeoylquinic acid derivatives. I. guayusa teas are a good source of dietary phenolic compounds with cellular antioxidant and anti-inflammatory properties.

Two new 18, 19-seco Triterpenoids from Ilex asprella (Hook. et Arn.) Champ. ex Benth

Two novel 18,19-seco-ursane triterpenoid saponins, ilexasprellanosides J-K (1-2, resp.), 3-O-α-l-Rhamnopyranosyl-(1 → 2)-β-d-xylopyrannosyl-19-O-β-d-glucopyranosyl-16-β-hydroxyl-18,19-seco-13(18)-urs-ene-21, 28-lactone (1), 3-O-β-d-Xylopyrannosyl-19-O-α-l-rhamnopyran osyl-(1 → 2)-α-l-arabinopyranoside-16, 21-epoxy-18, 19-seco-13(18)-urs-ene-28-oic acid (2), five known compounds (3-7) were isolated from the leaves of Ilex asprella (Hook. et Arn.) Champ. ex Benth. (Gangmeiye). The chemical structures of these compounds were elucidated through UV, IR, ESI-MS, ¹H NMR and ¹³C NMR analyses. In MTT and SRB assays, compounds 1-4 presented cytotoxic activities against several human cancer cell lines, namely, the HL-60 human acute promyelocytic leukaemia, Bel 7402 liver cancer, BGC-823 gastric cancer and KB human nasopharyngeal carcinoma cell lines. Compound 1 exhibited weak cytotoxic activities against the human tumour cell lines HL-60, Bel 7402 and KB with inhibition rates of 27.97%, 21.00% and 25.60%, respectively. Compound 2 exhibited weak cytotoxic activities against the human tumour cell lines HL-60, Bel 7402 and BGC-823 with inhibition rates of 19.34%, 7.50% and 4.26%. Respectively, the compounds exerted no statistically different effects on mast cell degranulation in rats. This result indicates that the compounds do not affect mast cell degranulation.

Simultaneous Qualitative and Quantitative Analyses of Triterpenoids in Ilex pubescens by Ultra-High-Performance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry

INTRODUCTION

Ilex pubescens Hook et Arn mainly contains triterpenoids that possess antithrombotic, anti-inflammatory and analgesic effects. Quantitative and qualitative analyses of the triterpenoids in I. pubescens can be useful for determining the authenticity and quality of raw materials and guiding its clinical preparation.

OBJECTIVES

To establish a method for rapid and comprehensive analysis of triterpenoids in I. pubescens using ultra-high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight-mass spectrometry (UPLC-ESI-QTOF-MS), which will also be applied to evaluate the contents of nine triterpenoids among root, root heartwood and root bark of I. pubescens to judge the value of the root bark to avoid wastage.

METHODS

UPLC-ESI-QTOF-MS data from the extracts of I. pubescens in negative mode were analysed using Peakview and Masterview software that provided molecular weight, mass errors, isotope pattern fit and MS/MS fragments for the identification of triterpenoids. The quantification of nine investigated compounds of I. pubescens was accomplished using MultiQuant software.

RESULTS

A total of 33 triterpenoids, five phenolic acids, two lignans and a flavonol were characterised in only 14 min. The total content of the nine compounds in the root bark was generally slightly higher than that of the root and root heartwood, which has not been reported before.

CONCLUSION

The developed UPLC-ESI-QTOF-MS method was proven to be rapid and comprehensive for simultaneous qualitative and quantitative analyses of the characteristic triterpenoids in I. pubescens. The results may provide a basis for holistic quality control and metabolic studies of I. pubescens, as well as serve as a reference for the analysis of other Ilex plants. Copyright © 2017 John Wiley & Sons, Ltd.

Integral Phylogenomic Approach over Ilex L. Species from Southern South America

The use of molecular markers with inadequate variation levels has resulted in poorly resolved phylogenetic relationships within Ilex. Focusing on southern South American and Asian species, we aimed at contributing informative plastid markers. Also, we intended to gain insights into the nature of morphological and physiological characters used to identify species. We obtained the chloroplast genomes of I.paraguariensis and I. dumosa, and combined these with all the congeneric plastomes currently available to accomplish interspecific comparisons and multilocus analyses. We selected seven introns and nine IGSs as variable non-coding markers that were used in phylogenomic analyses. Eight extra IGSs were proposed as candidate markers. Southern South American species formed one lineage, except for I. paraguariensis, I. dumosa and I. argentina, which occupied intermediate positions among sampled taxa; Euroasiatic species formed two lineages. Some concordant relationships were retrieved from nuclear sequence data. We also conducted integral analyses, involving a supernetwork of molecular data, and a simultaneous analysis of quantitative and qualitative morphological and phytochemical characters, together with molecular data. The total evidence tree was used to study the evolution of non-molecular data, evidencing fifteen non-ambiguous synapomorphic character states and consolidating the relationships among southern South American species. More South American representatives should be incorporated to elucidate their origin.

In vitro polyphenol effects on apoptosis: An update of literature data

Polyphenols are secondary plant metabolites which have been studied extensively for their health-promoting properties, and which could also exert pharmacological activities ranging from anti-inflammatory effects, to cytotoxic activity against cancer cells. The main mechanism for programmed cell death is represented by apoptosis, and its dysregulation is involved in the etiopathology of cancer. As such, substances able to induce apoptosis in cancer cells could be used as new anticancer agents. The aim of this paper is to review literature data on the apoptotic effects of polyphenols and the molecular mechanisms through which they induce these effects in cancer cells. In addition, a brief summary of the new delivery forms used to increase the bioavailability, and clinical impact of polyphenols is provided. The studies reported show that many polyphenol rich plant extracts, originating from food and herbal medicine, as well as isolated polyphenols administered individually or in combination, can regulate cell apoptosis primarily through intrinsic and extrinsic mechanisms of action in in vitro conditions. Due to these promising results, the use of polyphenols in the treatment of cancer should therefore be deeply investigated. In particular, because of the low number of clinical trials, further studies are required to evaluate the anticancer activity of polyphenols in in vivo conditions.

Transcriptomic Comparison Reveals Candidate Genes for Triterpenoid Biosynthesis in Two Closely Related Ilex Species

Native to Southern China, Ilex pubescens and Ilex asprella are frequently used in traditional Chinese medicine. Both of them produce a large variety of ursane-type triterpenoid saponins, which have been demonstrated to have different pharmacological effects. However, little is known about their biosynthesis. In this study, transcriptomic analysis of I. pubescens and comparison with its closely related specie I. asprella were carried out to identify potential genes involved in triterpenoid saponin biosynthesis. Through RNA sequencing (RNA-seq) and de novo transcriptome assembly of I. pubescens, a total of 68,688 UniGene clusters are obtained, of which 32,184 (46.86%) are successfully annotated by comparison with the sequences in major public databases (NCBI, Swiss-Prot, and KEGG). It includes 128 UniGenes related to triterpenoid backbone biosynthesis, 11 OSCs (oxidosqualene cyclases), 233 CYPs (cytochrome P450), and 269 UGTs (UDP-glycosyltransferases). By homology-based blast and phylogenetic analysis with well-characterized genes involved in triterpenoid saponin biosynthesis, 5 OSCs, 14 CYPs, and 1 UGT are further proposed as the most promising candidate genes. Transcriptomic comparison between two Ilex species using blastp and OrthoMCL method reveals high sequence similarity. All OSCs and UGTs as well as most CYPs are classified as orthologous genes, while only 5 CYPs in I. pubescens and 3 CYPs in I. asprella are species-specific. One of OSC candidates, named as IpAS1, was successfully cloned and expressed in Saccharomyces cerevisiae INVSc1. Analysis of the yeast extract by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) shows IpAS1 is a mixed amyrin synthase, producing α-amyrin and β-amyrin at ratio of 5:1, which is similar to its ortholog IaAS1 from I. asprella. This study is the first exploration to profile the transcriptome of I. pubescens, the generated data and gene models will facilitate further molecular studies on the physiology and metabolism in this plant. By comparative transcriptomic analysis, a series of candidate genes involved in the biosynthetic pathway of triterpenoid saponins are identified, providing new insight into their biosynthesis at transcriptome level.

Antioxidant and cardioprotective effects of Ilex cornuta on myocardial ischemia injury

Previous studies have indicated that the Ilex genus exhibits antioxidant, neuroprotective, hepatoprotective, and anti-inflammatory activities. However, the pharmacologic action and mechanisms of Ilex cornuta against cardiac diseases have not yet been explored. The present study was designed to investigate the antioxidant and cardioprotective effects of Ilex cornuta root with in vitro and in vivo models. The anti-oxidative effects of the extract of Ilex cornuta root (ICR) were measured by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging and MTT assays as well as immunoassay. Furthermore, a rat model of myocardial ischemia was established to investigate the cardioprotective effect of ICR in vivo. Eight compounds were isolated and identified from ICR and exhibited DPPH free-radical scavenging activities. They also could increase cell viability and inhibit morphological changes induced by H₂O₂ or Na₂S₂O₄ in H9c2 cardiomyocytes, followed by increasing the SOD activities and decreasing the MDA and ROS levels. In addition, it could suppress the apoptosis of cardiomyocytes. In the rat model of myocardial ischemia, ICR decreased myocardial infarct size and suppressed the activities of LDH and CK. Furthermore, ICR attenuated histopathological alterations of heart tissues and the MDA levels, while increasing SOD activities in serum. In conclusion, these results suggest that ICR has cardioprotective activity and could be developed as a new food supplement for the prevention of ischemic heart disease.

Research progress in phytochemistry and biology of Aframomum species

CONTEXT

The African genus Aframomum (Zingiberaceae) is a group of diverse tropical plants frequently collected yet largely neglected taxonomically. The current and unprecedented loss of species due to man-made habitat destruction and climate change adds a desperate urgency not only to understand the phylogenetics, chemotaxonomy and biology, but also to preserve the quickly disappearing species.

OBJECTIVES

The present systematic review reports on the research progress in phytochemistry, pharmacology and toxicology of Aframomum species.

METHODOLOGY

Scientific databases such as MedSci, PubMed, Scopus, Google Scholar and Web of Knowledge were used to retrieve publications (from the year 1990 to 2014) related to Aframomum plants, isolated compounds and their bioactivity, phytochemistry and toxicology. The keywords combinations for the search were: Aframomum; chemotaxonomy, phylogenetics, pharmacology and bioactive metabolites and toxicology. A total of 71 research articles that report on the biological activity of extracts and chemical constituents were recovered and presented in this review.

RESULTS

Most published data related to the potential of Aframomum melegueta, a medicinal plant from West and Central Africa. The potential of phenols and terpenoids isolated from Aframomum plants were generally much better documented than that of arylalkanoids.

CONCLUSION

Aframomum genus represents an enormous resource for novel compounds with a range of medicinal properties. However, these plants are under-researched and their conservation is poor. To unravel their full potential, efforts should be strengthened throughout the continent to establish the taxonomy, preserve the genus and explore novel medicinal properties.

Ilex kaushue and Its Bioactive Component 3,5-Dicaffeoylquinic Acid Protected Mice from Lipopolysaccharide-Induced Acute Lung Injury

Acute lung injury (ALI) is a severe respiratory disease with high mortality rates worldwide. Recent reports suggest that human neutrophil elastase (HNE) plays a key role in the inflammatory response that is characteristic of ALI, which indicates that the development of HNE inhibitors could be an efficient treatment strategy. In the current study, an enzyme-based screening assay was used to identify effective HNE inhibitors from a number of traditional Chinese medicines (TCMs). Among them, a water extract of Ilex kaushue (IKWE) effectively inhibited HNE activity (IC₅₀, 11.37 ± 1.59 μg/mL). Using bioactivity-guided fractionation, one new compound and 23 known compounds were identified. Compound 6 (identified as 3,5-dicaffeoylquinic acid; 3,5-DCQA) exerted the most potent and selective inhibitory effect on HNE activity (IC₅₀, 1.86 ± 0.06 μM). In a cell-based assay, 3,5-DCQA not only directly reduced superoxide generation and elastase activity but also attenuated the Src family kinase (SRKs)/Vav signaling pathway in N-formyl-L-Met-L-Leu-L-Phe (fMLF)-stimulated human neutrophils. In an animal disease model, both 3,5-DCQA and standardized IKWE protected against lipopolysaccharide-induced ALI in mice, which provides support for their potential as candidates in the development of new therapeutic agents for neutrophilic inflammatory diseases.

General and Genetic Toxicology of Guayusa Concentrate (Ilex guayusa)

Tea from the leaves of guayusa (Ilex guayusa) has a long history of consumption by Ecuadorian natives in regions where the plant is indigenous. The tea contains the methylxanthines caffeine and theobromine as well as chlorogenic acids, flavonoids, and sugars. Various studies were performed to evaluate the general and genetic toxicology of a standardized liquid concentrate of guayusa (GC). Guayusa concentrate was found to be negative in in vitro genotoxicity tests including the Ames test and a chromosome aberration study in human lymphocytes. The oral median lethal dose (LD50) of GC was >5,000 mg/kg for female rats. Guayusa concentrate was administered to male and female rats in a 90-day subchronic study at 1,200, 2,500, and 5,000 mg/kg/d of GC and a caffeine-positive control at 150 mg/kg/d corresponding to the amount of caffeine in the high-dose GC group. Effects observed in the GC-treated groups were comparable to those in the caffeine control group and included reductions in body weights, food efficiency, triglycerides values, and fat pad weights and increases in blood chemistry values for serum aspartate aminotransferase, serum alanine aminotransferase, and cholesterol and adaptive salivary gland hypertrophy. No signs of incremental toxicity due to any other components of guayusa were observed. The studies indicate no harmful effects of GC in these test systems.

Crude triterpenoid saponins from Ilex latifolia (Da Ye Dong Qing) ameliorate lipid accumulation by inhibiting SREBP expression via activation of AMPK in a non-alcoholic fatty liver disease model

BACKGROUND

Ilex latifolia Thunb. (Da Ye Dong Qing) is used for weight loss and for its antidiabetic effects. This study aims to investigate the beneficial effects and potential mechanisms of action of crude triterpenoid saponins (CTS) from I. latifolia in a mouse model of high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD).

METHODS

Male C57BL/6 mice (n = 50), were arbitrarily divided into five groups (n = 10 in each group): a control group, HFD group, simvastatin group (10 mg/kg/day), and two CTS treatment groups (100 and 200 mg/kg/day). All mice except those in the control group were fed an HFD for 4 weeks. Animals in the treatment groups were orally administered simvastatin or CTS for 8 weeks. Oral glucose tolerance tests and insulin tolerance tests were performed. At the end of treatment, plasma lipid levels, and oxidative parameters in the liver were measured using commercial test kits. Western blotting was used to evaluate whether CTS induced AMP-activated protein kinase (AMPK) and acetyl CoA carboxylase activation, and the expression of transcription factors and their target genes was evaluated in a quantitative PCR assay.

RESULTS

Compared with the HFD group, the CTS (200 mg/kg/day) treatment group showed significantly decreased plasma lipid parameters (P < 0.001, P = 0.018, and P = 0.005 for triglycerides, total cholesterol and low-density lipoprotein cholesterol, respectively), and improved insulin resistance (P = 0.006). CTS (100 and 200 mg/kg/day) supplementation also reduced hepatic lipids and protected the liver from oxidative stress by attenuating malondialdehyde content (P < 0.001 and P < 0.001, respectively) and restoring aspartate aminotransferase levels (P < 0.001 and P < 0.001, respectively). Moreover, CTS (200 mg/kg/day) reduced lipid accumulation by enhancing AMPK phosphorylation and inhibiting expression of sterol regulatory element-binding proteins (SREBPs) and their target genes SREBP-1c, SREBP-2, fatty acid synthase, and stearoyl-CoA desaturase (P = 0.013, P = 0.007, P = 0.011, and P = 0.014, respectively).

CONCLUSION

CTS from I. latifolia improved insulin resistance and liver injury in HFD-fed mice, and attenuated NAFLD via the activation of AMPK and inhibition of the gene expression of SREBPs and some of their target molecules.

Development of microsatellite markers in Ilex kaushue (Aquifoliaceae), a medicinal plant species

PREMISE OF THE STUDY

Microsatellite markers were developed for Ilex kaushue (Aquifoliaceae), a medicinal plant with extremely small wild populations that exists in fragmented habitats, to assess and protect its genetic diversity.

METHODS AND RESULTS

Using 454 GS FLX Titanium sequencing, 16 microsatellite primer sets were isolated and characterized. Fifteen of these markers were polymorphic. The number of alleles per locus ranged from one to nine across 22 individuals from both cultivated and wild populations. The observed and expected heterozygosity in these two populations ranged from 0.000 to 1.000 and from 0.000 to 0.785, respectively.

CONCLUSIONS

These markers will be useful in studies on genetic diversity of I. kaushue.

Accelerated maturation of processed yerba-mate under the controlled conditions of temperature and humidity

Purpose

– The purpose of this paper was to assess the changes in secondary metabolites and color during yerba-mate aging under controlled conditions. In Uruguay and Paraguay, the yerba-mate matured, in which chlorophyll degradation occurs, is preferred. For the matured product, the yerba-mate is stored for six months to one year.

Design/methodology/approach

– Processed yerba-mate was submitted to 35°C and 80 per cent humidity during 42 days in a climatic chamber. Samples were collected every seven days, and the phenolic compounds/methylxanthines were quantified by ultra-performance liquid chromatography – photodiode array and chlorophylls/phaeophytins by spectrophotometry. L*, a* and b* colorimetric coordinates were measured.

Findings

– The most expressive changes in the color occur in the first 14 days. At this time, 23.161 ± 2.984 per cent of total chlorophyll was degraded, considering that in 42 days, 37.458 ± 0.955 per cent is degraded, according to an exponential model. A positive correlation between theobromine amount and maturation time was found. This was verified by an increase in dicaffeoylquinic acid concentrations and small changes in chlorogenic acid isomers.

Practical implications

– The results indicate that this is a viable accelerated yerba-mate maturation process according to economics and nutraceutics.

Originality/value

– The paper has reported here a novel strategy to promote the yerba-mate maturation using controlled conditions.

Effects of UV light on the physic-chemical properties of yerba-mate

Purpose

– The aim of this paper is to evaluate the effects of ultraviolet (UV) light on the color, secondary metabolites and sensory acceptance of processed yerba-mate.

Design/methodology/approach

– Samples were exposed to UV light for 72 hours. The colorimetric coordinates (L*, a* and b*) were analyzed every 6 hours, while secondary metabolites and sensory acceptance were assessed at the beginning and at the end of the experiment. Methylxanthines and phenolic compounds were quantified by ultra performance liquid chromatography photodiode array detectors and vegetable pigments by UV/visible spectrophotometry.

Findings

– Decreases in methylxanthines, rutin and isomers of chlorogenic acids were found, along with an increase in isomers of dicaffeoylquinic acids. The product showed less sensory acceptance compared to the control. These results show that UV light treatment of yerba-mate accelerates the maturation process.

Practical implications

– UV light can be used in yerba-mate maturation with a reduction time and can ensure microbiological safety with small changes in its phytochemical profile.

Originality/value

– This paper is the first report of a novel strategy to investigate the yerba-mate maturation using UV light.