Monoterpenoid and phenylethanoid glycosides from Ligustrum pedunculare

The hydroxytyrosol-typed phenylpropanoidglycosides: A phenylpropanoid glycoside family with significant biological activity

Hydroxytyrosol-typed phenylpropanoid glycosides (HPGs), composed of phenylethanol and various complex oligosaccharides, are widespread and abundant in different plant, and have a diverse range of biological activities. All HPGs reported previously have been isolated from natural sources, and most of them showed significant bioactivities, such as anti-inflamatory, anti-cancer, cytoprotection, neuro-protective effects, enzyme-inhibitory, anti-microbial effects, and cardiovascular activity. The goal of this review is to summarize the structures of HPGs reported over the past few decades, as well as to introduce their pharmacological effects. We also introduce the possible relationship between the structures of HPGs and their source plants, as well as the structure-activity relationships of some important activities. This review will serve as a resource for future research into this class of compounds, and demonstrate their potential value.

Phenylethanoid glycosides from Michelia champaca leaves

Chemical investigation on the leaves of Michelia champaca L. (Magnoliaceae) led to the isolation of five previously undescribed phenylethanoid glycosides (PhGs), 4-O-β-d-glucopyranosyl-acteoside (1), 4‴-O-(6-O-E-caffeoyl)-β-d-glucopyranosyl-acteoside (2), 4‴-O-(6-O-E-caffeoyl)-β-d-glucopyranosyl-isoacteoside (3), 6""-O-E-feruloyl-echinacoside (4), and 6""-O-p-E-coumaroyl-echinacoside (5), together with eighteen known PhGs. Their structures were determined by spectroscopic and chemical methods. All the known PhGs except acteoside (8) were not previously reported in the genus. Twenty-one PhGs exhibited more potent DPPH radical scavenging activity and FRAP than l-ascorbic acid (l-AA), and twenty-two PhGs showed better ABTS radical cation scavenging activity than l-AA. In addition, twelve PhGs displayed more potent cellular reactive oxygen species scavenging activity than curcumin. The results revealed that the leaves of M. champaca are a rich source of phenylethanoid glycosides and antioxidants.

Monoterpenoid Glycosides from the Leaves of Ligustrum robustum and Their Bioactivities (II)

Ligustrum robustum has been not only used as a heat-clearing and detoxicating functional tea (Ku-Ding-Cha) but also consumed as a hypotensive, anti-diabetic, and weight-reducing folk medicine. From the leaves of L. robustum, ten new monoterpenoid glycosides named ligurobustosides T10 (1a), T11 (1b), T12 (2a), T13 (2b), T14 (3a), T15 (3b), F1 (4b), T16 (5a), T17 (5b), and E1 (6b), together with five known ones (4a, 6a, 7, 8a, 8b), were separated and identified using the spectroscopic method and chemical method in this research. The results of biological tests exhibited that the fatty acid synthase (FAS) inhibitory action of compound 5 (IC50: 4.38 ± 0.11 μM) was as strong as orlistat (IC50: 4.46 ± 0.13 μM), a positive control; the α-glucosidase inhibitory actions of compounds 1-4 and 7-8, and the α-amylase inhibitory actions of compounds 1-8 were medium; the ABTS radical scavenging capacities of compounds 1-3 and 5-8 (IC50: 6.27 ± 0.23 ~ 8.59 ± 0.09 μM) were stronger than l-(+)-ascorbic acid (IC50: 10.06 ± 0.19 μM) served as a positive control. This research offered a theoretical foundation for the leaves of L. robustum to prevent diabetes and its complications.

Complete biosynthesis of the phenylethanoid glycoside verbascoside

Verbascoside, which was first discovered in 1963, is a well-known phenylethanoid glycoside (PhG) that exhibits antioxidant, anti-inflammatory, antimicrobial, and neuroprotective activities and contributes to the therapeutic effects of many medicinal plants. However, the biosynthetic pathway of verbascoside remains to be fully elucidated. Here, we report the identification of two missing enzymes in the verbascoside biosynthesis pathway by transcriptome mining and in vitro enzymatic assays. Specifically, a BAHD acyltransferase (hydroxycinnamoyl-CoA:salidroside hydroxycinnamoyltransferase [SHCT]) was shown to catalyze the regioselective acylation of salidroside to form osmanthuside A, and a CYP98 hydroxylase (osmanthuside B 3,3'-hydroxylase [OBH]) was shown to catalyze meta-hydroxylations of the p-coumaroyl and tyrosol moieties of osmanthuside B to complete the biosynthesis of verbascoside. Because SHCTs and OBHs are found in many Lamiales species that produce verbascoside, this pathway may be general. The findings from the study provide novel insights into the formation of caffeoyl and hydroxytyrosol moieties in natural product biosynthetic pathways. In addition, with the newly acquired enzymes, we achieved heterologous production of osmanthuside B, verbascoside, and ligupurpuroside B in Escherichia coli; this work lays a foundation for sustainable production of verbascoside and other PhGs in micro-organisms.

Lignans and Phenylethanoid Glycosides from the Aerial Parts of Pogostemon cablin

Two new lignans (1-2) and a new octaketide (12), together with twenty-nine known compounds (3-11, 13-32) were isolated and identified from the aerial part of Pogostemon cablin. Their chemical structures were revealed mainly through NMR and MS data. The absolute configuration of 1 and 2 was deduced by comparing its experimental CD with the calculated ECD spectra. The inhibitory activities of the isolated compounds on LPS-stimulated nitric oxide (NO) production in RAW 264.7 cells were investigated. At a concentration of 25 μM, compounds 1 and 11 showed approximately equal NO inhibitory effects to that of aminoguanidine.

Duranta erecta Linn: A critical review on phytochemistry, traditional uses, pharmacology, and toxicity from phytopharmaceutical perspective

ETHNOPHARMACOLOGICAL RELEVANCE

Duranta erecta Linn. belonging to the Verbenaceae family is widely used in the traditional systems of medicines practiced in Bangladesh, India, Nigeria, the Philippines, and Brazil. The ethnomedicinal application as vermifuge, febrifuge, diuretic, anti-parasitic, and anti-malarial are well documented. D. erecta is also a significant source of phenylethanoid glycoside known as acteoside-a drug in clinical trials for IgA nephropathy patients.

AIM OF THIS REVIEW

This review aims to critically highlight the existing studies on D. erecta, including its botanical authentication, geographical distribution, ethnomedicinal uses, phytochemistry, and pharmacological properties. Critical discussion is focused on the overview and gap in knowledge for future research. Additionally, the clinical significance of its major secondary metabolite, i.e., acteoside, has also been discussed with emphasis on biosynthesis, distribution, pre-clinical, and clinical outcomes.

MATERIALS AND METHODS

Professional research data from 1963 to 2021 appeared in scholarly journals, and books were retrieved from scientific database platforms viz. Sci-Finder, PubMed, CNKI, Science Direct, Web of Science, Wiley, Google Scholar, Taylor and Francis, Springer, and Scopus. The chemical structures for all the phytomolecules were validated using Sci-finder and first-hand references. While plant name and synonyms were corroborated by "The Plant List" (www.theplantlist.org).

RESULTS

D. erecta and its key metabolite acteoside display various biological actions like antimalarial, antimicrobial, antioxidant, anticancer, antinephritic, hepatoprotective, neuroprotective, and antiviral properties. Acteoside literature analysis shows its presence in different stages of clinical trials for anti-nephritic, hepatoprotective, and osteoarthritic activity. The phytochemical review of D. erecta exhibited 64 compounds that have been isolated and identified from D. erecta, such as iridoid glycosides, phenylethanoid glycosides, flavonoids, steroids, phenolics, terpenoids, and saponins. The other significant secondary metabolites responsible for its medicinal properties are acteoside, durantol, pectolinaringenin, repenins, scutellarein, and repennoside.

CONCLUSION

Duranta erecta is one of the Verbenaceae plants, widely used in ethnomedicines having various phytochemicals with understandable pharmacological actions mainly confined at the crude extract level. However, further bioactivity-guided or fingerprint-assisted studies are required to validate the ethnomedicinal uses, concerning cellular and molecular mechanisms, quality standardization, and safety with respect to its bioactive constituent(s). Therefore, the present review identified the gap in the research on scientific validation of Duranta based ethnomedicines and may provide critical information for the development of phytopharmaceuticals/Phyto-cosmeceuticals.

Monoterpenoid Glycosides from the Leaves of Ligustrum robustum and Their Bioactivities

The leaves of Ligustrum robustum have been applied as Ku-Ding-Cha, a functional tea to clear heat, remove toxins, and treat obesity and diabetes, in Southwest China. The phytochemical research on the leaves of L. robustum led to the isolation and identification of eight new monoterpenoid glycosides (1–8) and three known monoterpenoid glycosides (9–11). Compounds 1–11 were tested for the inhibitory activities on fatty acid synthase (FAS), α-glucosidase, α-amylase, and the antioxidant effects. Compound 2 showed stronger FAS inhibitory activity (IC₅₀: 2.36 ± 0.10 μM) than the positive control orlistat (IC₅₀: 4.46 ± 0.13 μM), while compounds 1, 2, 5 and 11 displayed more potent ABTS radical scavenging activity (IC₅₀: 6.91 ± 0.10~9.41 ± 0.22 μM) than the positive control L-(+)-ascorbic acid (IC₅₀: 10.06 ± 0.19 μM). This study provided a theoretical basis for the leaves of L. robustum as a functional tea to treat obesity.

Anticancer effects of acteoside: Mechanistic insights and therapeutic status

Cancer, the uncontrolled proliferation and metastasis of abnormal cells, is a major public health issue worldwide. To date, several natural compounds have been reported with their efficacy in the treatment of different types of cancer. Chemotherapeutic agents are used in cancer treatment and prevention, among other aspects. Acteoside is a phenylethanoid glycoside, first isolated from Verbascum sinuatum, which has demonstrated multiple effects, including antioxidant, anti-epileptic, neuroprotective, anti-inflammatory, antifungal, antihypertensive, and anti-leishmanial properties. This review gathered, analyzed, and summarized the literature on acteoside and its anticancer properties. All the available information about this compound and its role in different types of cancer was collected using different scientific search engines, including PubMed, Scopus, Springer Link, Wiley Online, Web of Science, Scifinder, ScienceDirect, and Google Scholar. Acteoside is found in a variety of plants and has been shown to have anticancer activity in many experimental models through oxidative stress, apoptosis, anti-angiogenesis, anti-invasion, anti-metastasis, synergism with other agents, and anti-proliferative effects through modulation of several pathways. In conclusion, acteoside exhibited potent anticancer activity against different cancer cell lines through modulating several cancer signaling pathways in different non- and pre-clinical experimental models and thus could be a strong candidate for further clinical studies.

Acteoside as a potential therapeutic option for primary hepatocellular carcinoma: a preclinical study

Background

Hepatocellular carcinoma (HCC) is a common malignant tumor with characteristics of poor prognosis, high morbidity and mortality worldwide. In particular, only a few systemic treatment options are available for advanced HCC patients, and include sorafenib and the recently described atezolizumab plus bevacizumab regimen as possible first-line treatments. We here propose acteoside, a phenylethanoid glycoside widely distributed in many medicinal plants as a potential candidate against advanced HCC.

Methods

Cell proliferation, colony formation and migration were analyzed in the three human HCC cell lines BEL7404, HLF and JHH-7. Angiogenesis assay was performed using HUVESs. The BEL7404 or JHH-7 xenograft nude mice model was established to analyze the possible antitumor effects of acteoside. qRT-PCR and western blotting were used to reveal the potential antitumor mechanisms of acteoside.

Results

Acteoside inhibited cell proliferation, colony formation and migration in all the three human HCC cell lines BEL7404, HLF and JHH-7. The prohibition of angiogenesis by acteoside was revealed by the inhibition of tube formation and cell migration of HUVECs. The combination of acteoside and sorafenib produced stronger inhibition of cell colony formation and migration of the HCC cells as well as of angiogenesis of HUVECs. The in vivo antitumor efficacy of acteoside was further demonstrated in BEL7404 or JHH-7 xenograft nude mice model, with an enhancement when combined with sorafenib in inhibiting the growth of JHH-7 xenograft. Further treatment of JHH-7 cells with acteoside revealed an increase in the level of tumor suppressor protein p53 as well as a decrease of kallikrein-related peptidase (KLK1, 2, 4, 9 and 10) gene level with no significant changes of the rest of KLK1–15 genes.

Conclusions

Acteoside exerts an antitumor effect possibly through its up-regulation of p53 levels as well as inhibition of KLK expression and angiogenesis. Acteoside could be useful as an adjunct in the treatment of advanced HCC in the clinic.

Therapeutic potential of phenylethanoid glycosides: A systematic review

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure-activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.

Preparative Separation of Phenylethanoid and Secoiridoid Glycosides from Ligustri Lucidi Fructus by High-Speed Counter-Current Chromatography Coupled with Ultrahigh Pressure Extraction

Three phenylethanoid glycosides, echinacoside (1), salidroside (3), and acteoside (6), and three secoiridoid glycosides, isonuezhenide (2), nuezhenoside G13 (4), and specnuezhenide (5), have been extracted and separated by a combined method of ultrahigh pressure extraction (UPE) and high-speed counter-current chromatography (HSCCC) from Ligustri Lucidi Fructus. For the UPE, the optimal extraction was developed with conditions including solvent of 90% ethanol, sample to solvent ratio of 1:20 g/mL, pressure of 200 MPa, and time of 2 min, which rendered the yields of compounds 4 and 5 were 15.0 and 78.0 mg/g, respectively. For the HSCCC separation, the strategy of changing flow rates between 1.0 and 2.0 mL/min allowed the acquisition for 2.7 mg of compound 1, 4.5 mg of compound 2, 6.8 mg of compound 3, 5.9 mg of compound 4, 11.2 mg of compound 5, and 2.2 mg of compound 6 in one separation run under the solvent system of ethyl acetate:n-butanol:water (2:1:3, v/v) from 200 mg of the UPE extract. The structures of these phenylethanoid and secoiridoid glycosides were elucidated by extensive spectroscopic methods.

Screening of Biological Activities of Ligustrum lucidum Berries: A Comparative Approach

Ligustrum lucidum Aiton including its berries have been used in Chinese Traditional Medicine for around 2000 years. Scientific studies developed on the last decades provided evidence on some biological properties of these products, mostly from particular geographic origins. In the present study, L. lucidium berries harvested in two regions of Portugal were considered. Extracts obtained with 100% ethanol, with 50% ethanol/water (v/v) and in boiled water were prepared and several parameters were assessed: antioxidant activity (using two methodologies), antimicrobial activity and phenolic profile. Results suggest that the different biological activities varied according to the region where samples were collected but also with the extraction methodology. Superior antioxidant potential was observed in water extracts, according to both assays, while for the remaining activities the ethanol 50% extracts had the highest activity. In these regions, the L. lucidum berries showed promising biological activities and may be interesting sources of compounds for the development of new drugs for diseases where oxidant reactive species and enzymatic disruption are believed to play a role as well as adjuvants for current antibiotic therapy.

Attractive but Toxic: Emerging Roles of Glycosidically Bound Volatiles and Glycosyltransferases Involved in Their Formation

Plants emit an overabundance of volatile compounds, which act in their producers either as appreciated attractants to lure beneficial animals or as repellent toxins to deter pests in a species-specific and concentration-dependent manner. Plants have evolved solutions to provide sufficient volatiles without poisoning themselves. Uridine-diphosphate sugar-dependent glycosyltransferases (UGTs) acting on volatiles is one important part of this sophisticated system, which balances the levels of bioactive metabolites and prepares them for cellular and long-distance transport and storage but enables the remobilization of disarmed toxins for the benefit of plant protection. This review provides an overview of the research history of glycosidically bound volatiles (GBVs), a relatively new group of plant secondary metabolites, and discusses the role of UGTs in the production of GBVs for plant protection.

Effects of Phytochemically Characterized Extracts From Syringa vulgaris and Isolated Secoiridoids on Mediators of Inflammation in a Human Neutrophil Model

Aim of the study: The aim of the present study was to investigate the effects of phytochemically characterized extracts connected with the traditional use (infusions and ethanolic extracts) of different parts of Syringa vulgaris (common lilac) on the pro-inflammatory functions of neutrophils. Active compounds were isolated from the most promising extract(s) using bioassay-guided fractionation, and their activity and molecular mechanisms of action were determined.

Methods: The extracts were characterized using a HPLC-DAD- MSⁿ method. The effects on ROS, MMP-9, TNF-α, IL-8, and MCP-1 production by neutrophils were measured using luminol-dependent chemiluminescence and enzyme-linked immunosorbent assay (ELISA) methods. The effects on p38MAPK, ERK1/2, JNK phosphorylation, and NF-kB p65 translocation were determined using western blots.

Results: The major compounds detected in the extracts and infusions belong to structural groups, including caffeic acid derivatives, flavonoids, and iridoids. All extracts and infusions were able to significantly reduce ROS and IL-8 production. Bioassay-guided fractionation led to the isolation of the following secoiridoids: 2″-epiframeroside, oleonuezhenide, oleuropein, ligstroside, neooleuropein, hydroxyframoside, and framoside. Neooleuropein appeared to be the most active compound in the inhibition of cytokine production by attenuating the MAP kinase pathways.

Conclusion: The present study demonstrated that common lilac, which is a traditionally used medicinal plant in Europe, is a valuable source of active compounds, especially neooleuropein.

In Vitro Anti-Inflammatory Activity of Ilex cornuta Extract Mediated by Inhibition of Extracellular Signal-Regulated Kinase Phosphorylation

Ilex cornuta, commonly known as Chinese holly, is an evergreen shrub from the family Aquifoliaceae, and it is widely distributed in Korea and China. In folk medicine, the leaves of I. cornuta are used for treatment of several disorders, including weakness of the waist and knees, arthrodynia, headache, acute conjunctivitis, toothache, urticaria, rheumatic arthralgia, and cardiovascular diseases. In this study, we investigated the anti-inflammatory effects of an I. cornuta leaf ethanol extract (ILE) and its underlying mechanisms of action. The anti-inflammatory activities of ILE were evaluated in murine RAW 264.7 macrophages, using lipopolysaccharide (LPS) stimulation. ILE treatment-related changes in the production of nitric oxide (NO), prostaglandin E₂ (PGE₂), and proinflammatory cytokines were also measured. Finally, the expression of signaling molecules involved in inflammatory reactions was also assessed. Pretreatment of macrophages with ILE attenuated the expression of inducible NO synthase and cyclooxygenase-2, resulting in a decrease in NO and PGE₂ production. The secretion of proinflammatory cytokines such as interleukin (IL)-6 and IL-1β was also reduced. Furthermore, ILE reduced extracellular signal-regulated kinases (ERK) phosphorylation, without affecting the inhibitor of kappa Bα and other mitogen-activated protein kinases. Liquid chromatography-tandem mass spectrometry analysis (LC-MS/MS) demonstrated that 1 g of ILE contains 27 mg of kaempferol, 0.3 mg of vanillic acid, and 21 mg of combined amount of isoquercetin and hyperin, among which isoquercetin and kaempferol significantly suppressed IL-6, IL-1β, and PGE₂ production. Our results demonstrated that ILE possesses anti-inflammatory effects mediated through inhibition of ERK phosphorylation.

Dereplication-Guided Isolation of New Phenylpropanoid-Substituted Diglycosides from Cistanche salsa and Their Inhibitory Activity on NO Production in Macrophage

Dereplication allows for a rapid identification of known and unknown compounds in plant extracts. In this study, we performed liquid chromatography-mass spectroscopy (LC-MS)- based dereplication using data from ESI⁺ QTOF-MS for the analysis of phenylpropanoid-substituted diglycosides, the major active constituents of Cistanche salsa (C. A. Mey.) Beck. Using TOF-MS alone, the substructures of these compounds could be unambiguously confirmed based on the characteristic fragmentation patterns of various product ions. HPLC-MS based profiling of C. salsa also allowed for the detection of new phenylpropanoid-substituted diglycosides from this plant. Of them, five new phenylpropanoid-substituted diglycosides, named cistansalsides A–E (5, 6, 12, 17 and 18), were isolated. Their structures were elucidated through spectroscopic methods including NMR and MS analysis. All the isolates were tested for their inhibitory activity against NO production in RAW 264.7 cells stimulated by LPS. Of the tested compounds, compounds 5, 11, 13 and 18 showed moderate inhibitory activity on inducible NO synthase. Compounds 11, 13 and 18 also inhibited the phosphorylation of NF-κB in macrophages. None of the compounds displayed significant cytotoxicity.

Eucalyptus pollen allergy and asthma in children: a cross-sectional study in South-East Queensland, Australia

Objectives

To investigate Eucalyptus (gum tree) pollen allergy in children in relation to geography, particularly vegetation, and its relationship to asthma.

Methods

Males (n = 180) and females (n = 200) aged 9 to 14 participated. Some were healthy (asymptomatic), some had asthma, and some had other symptoms associated with atopy. School students were from three urban coastal schools and one school from a nearby semi-rural elevated area (range) near Brisbane, Australia. Coastal and range locations featured different distributions of Myrtaceae family vegetation (including Eucalyptus, Melaleuca, Leptospermum species). Skin prick test (SPT) responses to 15 commercial allergens were compared. As well, responses from coast versus range groups, and ‘asthma’ (n = 97) versus ‘healthy’ status (n = 107) groups, were compared.

Results

SPT responses (≥3mm wheal diameter) indicate that children with asthma are 31.1 times more likely to be allergic to Eucalyptus pollen extract (OR: 31.1; 95%CI 4.1- 235.7) compared to healthy children. Dust mite (p = .018), Eucalyptus (p = .046) and cockroach (p = .047) allergen SPT responses (wheals ≥3mm) were significantly greater in participants located on the coast versus range as determined by Fisher’s Exact Test (α .05). For each location, percentage of positive responses (wheals ≥3mm) was greatest for ‘dust mite’ (30.9%-46%), ‘cockroach’ (18.1% -35%) and ‘Bermuda grass’ (10.6%-19.4%).

Conclusions

The results support the hypothesis that proximity to Myrtaceae vegetation is related to positive SPT response and that Eucalyptus is an important allergen for children with asthma. Substantial response to olive allergen, in the absence of olive trees, suggests that the response may be driven by substances in other plants, perhaps Melaleuca quinquenervia, which abounds in coastal areas.

Implications

Response to Eucalyptus allergen indicates that changes in gardening practice in schools and public areas may be appropriate. The findings pose validity questions regarding the use of some commercial allergens due to cross-reactive responses and the sources of those responses.

The advances in research on the pharmacological effects of Fructus Ligustri Lucidi

Fructus Ligustri Lucidi is a well-known invigorator in Chinese materia medica with hepatoprotective effect, anticancer activity, antioxidant activity, and so on. And oleanolic acids are the major pharmacologically active components in Fructus Ligustri Lucidi. So it has great value in medical health, and may be developed to a complementary and alternative medicine through further research. In this paper, the advances in research on pharmacological effects of Fructus Ligustri Lucidi were summarized by reviewing the recent related literature.

Seasonal variations in metabolite profiling of the fruits of Ligustrum lucidum Ait

The metabolite profiling of fruits of the herb Ligustrum lucidum Ait collected during different months has been performed using ultra-performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC/QTOFMS) and multivariate statistical analysis techniques. The markers such as oleuropein acid, neonuezhenide, specnuezhenide, oleuropein and ligustrosidic acid accountable for such variations were identified through the loadings plot of principal component analysis (PCA), and the tentative identification of the markers is completed by comparing the mass spectra and retention times with those of reference compounds and/or tentatively assigned by matching empirical molecular formulae and MS/MS data with those of the known compounds published. Furthermore, one of the chemical markers, such as specnuezhenide, which is water-soluble, biologically active and also the predominant compound in this crude drug, was quantified by ultra-performance liquid chromatography coupled with a tunable UV detector (UPLC-TUV). The developed UPLC method provides good linearity (r(2)=0.9991), repeatability (RSD=2.96%), intra- and inter-day precisions (RSD=0.21%, 0.96%), with accuracies of 99.18-100.26% and a recovery of specnuezhenide of 97.57%. The fruits of L. lucidum Ait collected from August to December were tested. The results clearly show that the fruits of L. lucidum Ait harvested in October have the highest yields of specnuezhenide. It is also noted that the variations of content of specnuezhenide obtained by both methods have a strong correlation. This suggests that the newly proposed strategy is a reliable and simple method for the rapid discrimination of subtle variations, within the same plant species or strains, due to different seasonal collection times.

Comparison of major phenolic constituents and in vitro antioxidant activity of diverse Kudingcha genotypes from Ilex kudingcha, Ilex cornuta, and Ligustrum robustum

A total of seven Kudingcha genotypes from three plant species (Ilex kudingcha, Ilex cornuta, and Ligustrum robustum) with different geographic origins in China were investigated for their major phenolic compounds, individual and total phenolics contents, and in vitro antioxidant properties (ABTS, DPPH, FRAP, and OH assays). LC-PDA-APCI-MS analysis showed that Kudingcha genotypes from Ilex and Ligustrum had entirely different phenolic profiles. Major phenolics in Kudingcha genotypes from two Ilex species were mono- and dicaffeoylquinic acids, whereas those in a Kudingcha genotype from Ligustrum were phenylethanoid and monoterpenoid glycosides. All Kudingcha genotypes of Ilex exhibited significantly stronger antioxidant capacities than that of Ligustrum. Within six Ilex genotypes, great variation existed in their composition of individual phenolic compounds and their antioxidant properties. The comparative data and LC fingerprints obtained in this study may provide useful information for screening and breeding of better Kudingcha genotypes and also for their authentication and quality control.

Astonishing diversity of natural surfactants: 7. Biologically active hemi- and monoterpenoid glycosides

This review article presents 90 hemi- and 188 monoterpenoid glycosides, isolated and identified from plants and microorganisms, that demonstrate different biological activities. These natural bioactive glycosides are good prospects for future chemical preparations from these compounds as antioxidants and as anticancer, antimicrobial, and antibacterial agents. These glycosidic compounds have been subdivided into several groups, including hemiterpenoids; acyclic, monocyclic, and bicyclic monoterpenoids; and iridoid monoterpenoids.

Attenuated endothelium-mediated relaxation by acteoside in rat aorta: Role of endothelial [Ca2+]i and nitric oxide/cyclic GMP pathway

Acteoside and other phenylethanoid glycoside are contained in many plants that are widely used in traditional Chinese herbal medicine. Acteoside possesses multiple biological actions. Its effect on the vascular system is, however, incompletely understood. This study was aimed to investigate the role of endothelial [Ca2+]i, nitric oxide (NO), and cyclic GMP in acteoside-induced inhibition of endothelial NO-mediated relaxation in rat aorta. Acteoside reduced endothelial NO-dependent relaxation induced by acetylcholine (Ach) or A23187. Acteoside inhibited Ach-stimulated increase in tissue content of cyclic GMP in endothelium-intact rings. L-NNA abolished the stimulatory effect of Ach. Treatment with acteoside significantly suppressed bradykinin-induced increase in [Ca2+]i of cultured rat aortic endothelial cells. Acute exposure to acteoside (30 microM) did not affect the expression of eNOS mRNA in endothelium-intact rings. In summary, acteoside impairs endothelial NO-mediated aortic relaxation partially through inhibition of agonist-induced endothelial Ca2+ mobilization and Ca2+-dependent NO production and subsequent suppression of cyclic GMP formation. This novel pharmacological action if occurring in small vessels in vivo, may contribute to the reported anti-inflammatory effect of acteoside against NO-mediated vascular permeability-related acute edema.

Identi?cation and determination of ecdysone and phenylpropanoid glucoside and ?avonoids inLamium maculatum by capillary zone electrophoresis

The simultaneous determination of 20-hydroxy ecdysone (1), 3,7-dimethoxy-quercetin (2), acteoside (3) and rutin (4) in the mixture of leaf and stem, and the flower of Lamium maculatum has been investigated by capillary zone electrophoresis for the first time. With an electrolyte containing 30 mmol/L borate, at pH 9.47 and 20 kV applied voltage, the four active compounds were completely separated within 5 min with satisfactory results. The effects of concentration of borate and electrolyte pH on electrophoretic behavior and separation were studied. Regression equations revealed linear relationships (correlation coefficients 0.9998-0.9999) between the peak area of each analyte and the concentration. The levels of analytes in the different parts of Lamium maculatum were easily determined with recoveries ranging from 98.3 to 105.0%.

Anti-oxidative, anti-inflammatory and hepato-protective effects of Ligustrum robustum

Aqueous extract of processed leaves of Ligustrum robustum could dose-dependently scavenge superoxide radicals, inhibit lipid peroxidation, and prevent AAPH-induced hemolysis of red blood cells. In comparison with green tea, oolong tea and black tea, processed leaves of L. robustum exhibited comparable antioxidant potency in scavenging superoxide radicals and in preventing red blood cell hemolysis. By activity-guided fractionation, a glycoside-rich fraction named fraction B2 was separated and demonstrated to possess strong antioxidant effect. It was evaluated for its anti-inflammatory and hepato-protective activities. A single oral dose of fraction B2 at 0.5 g/kg could provide 51.5% inhibition on the vascular permeability change induced by intraperitoneal injection of acetic acid, but it could not inhibit croton oil-induced ear edema. On the other hand, fraction B2 exhibited moderate hepato-protective effect. Intragastric application of fraction B2 at 1.25, 2.5 or 5 g/kg 6 h after carbon tetrachloride administration could reduce the elevations of serum levels of aminotransferases (AST and ALT). Also, liver integrity was preserved, as liver sections from rats post-treated with fraction B2 showed a milder degree of fatty accumulation and necrosis. These results offer partial support to the traditional uses of the leaves of L. robustum as Ku-Ding-Cha.

Secoiridoid and iridoid glucosides from Syringa afghanica

Phytochemical investigation of the dried leaves of Syringa afghanica, has led to the isolation of nine secoiridoid glucosides, safghanosides A-H and 2"-epi-frameroside, as well as an iridoid glucoside, syringafghanoside along with nineteen known compounds. The structures were elucidated by spectroscopic and chemical means.

Antioxidative glucosides from the fruits of Ligustrum lucidum

The ethanol extract of the fruits of Ligustrum lucidum was shown to have inhibitory effects on the hemolysis of red blood cells induced by 2,2'-azo-bis-(2-amidinopropane) dihydrochloride. Bioassay-guided analysis led to the isolation of ten secoiridoid glucosides. Two of them were new, lucidumosides C and D. Their structures were elucidated by spectroscopic methods. The other eight compounds were identified as oleoside dimethyl ester, ligustroside, oleuropein, nuezhenide, isonuezhenide, neonuezhenide, lucidumoside A and lucidumoside B. Five compounds, oleoside dimethyl ester, oleuropein, neonuezhenide, lucidumoside B and lucidumoside C, exhibited strong antioxidant effect against hemolysis of red blood cells induced by free radicals.

Secoiridoid constituents from the fruits of Ligustrum lucidum

Two secoiridoid glucosides, lucidumosides A and B, as well as six known glucosides, oleoside dimethyl ester, ligustroside, oleuropein, nuezhenide, isonuezhenide, and neonuezhenide, were isolated from the fruits of Ligustrum lucidum. Their structures were elucidated by spectroscopic methods.

Changes in immunomodulatory activity of human mononuclear cells after cultivation with leaf decoctions from the genus Ligustrum L

Leaf decoctions from Ligustrum vulgare (LV) and Ligustrum delavayanum (LD) were studied for candidacidal activity, phagocytic activity studied on human mononuclear cells (MO) and complement activated by the classical pathway. Candidacidal activity was studied on Candida albicans SC 1539 incubated with MO. The decoction of LD increased the candidacidal activity of MO, whereas LV did not show any effect. The phagocytic activity of MO was decreased by the decoction of LV, whereas LD did not change the activity. The phagocytic index of MO incubated with LD decoction was increased, but use of the LV decoction did not show significant changes. Decoctions from LD and LV significantly decreased the haemolytic activity of complement activated by the classical pathway (conc. 0.78 mg/mL).

Triterpenoid saponins from Ilex latifolia

Three new triterpenoid saponins, latifolosides F, G, H were isolated from the leaves of Ilex latifolia. Their structures were elucidated on the basis of chemical and spectral evidence. Latifoloside F was determined to be 3-O-[alpha-L-rhamnopyranosyl(1-2)]-[beta-D-glucopyranosyl(1-3)-]- alpha-L-arabinopyranosyl ilexgenin B 28-O-[alpha-L-rhamnopyranosyl(1-2)]-beta-D-glucopyranoside. Latifoloside G was 3-O-[alpha-L-rhamnopyranosyl(1-2)]-[beta-D-glucopyranosyl(1-3)-]- alpha-L-arabinopyranosyl pomolic acid 28-O-[alpha-L-rhamnopyranosyl(1-2)]-beta-D-glucopyranoside. Latifolioside H(3) was 3-O-[alpha-L-rhamnopyranosyl(1-2)]-[beta-D-glucopyranosyl(1-3)-]- alpha-L-arabinopyranosyl siaresinolic acid 28-O-[alpha-L-rhamnopyranosyl(1-2)]-beta-D-glucopyranoside.

Glycoconjugated aroma compounds: occurrence, role and biotechnological transformation

The present paper reviews the occurrence of glycosidically bound aroma compounds in the plant kingdom and discusses different hypotheses concerning their role in plants. Emphasis is on biotechnological methods for flavor release and flavor enhancement through enzymatic hydrolysis of glycoconjugated aroma substances.

Triterpenes and triterpenoid glycosides from the leaves of Ilex kudincha

Two new triterpenes, alpha- and beta-kudinlactone, and six new triterpenoid glycosides, kudinosides D-G, I and J, were isolated from the leaves of Ilex kudincha. Their structures have been elucidated by spectroscopic and chemical means.