Evaluation of novel antioxidant triterpenoid saponins from the halophyte Salicornia herbacea

Effect of Saponin on Methylene Blue (MB) Photo-Antimicrobial Activity Against Planktonic and Biofilm Form of Bacteria

Bacterial resistance has led to the spread of bacterial infections such as chronic wound infections. Finding solutions for combating resistant bacteria in chronic wounds such as Staphylococcus aureus and Pseudomonas aeruginosa became an attractive theme among researchers. P. aeruginosa is a gram negative opportunistic human pathogenic bacterium that is difficult to treat due to its high resistance to antibiotics. S. aureus (gram negative bacterium) also has a high antibiotic resistance, so that it is resistant to vancomycin (VRSA), tetracycline, fluoroquinolones and beta-lactam antibiotics including penicillin and methicillin (MRSA). In particular, S. aureus and P. aeruginosa have intrinsic and acquired antibiotic resistance, making the clinical management of infection a real challenge, especially in patients with comorbidities. aPDT can be proposed as a new method in the treatment of multi-drug resistant bacteria in chronic wound infection conditions. In this study, the effect of saponin (100 μg/mL) on photodynamic inactivation on planktonic and biofilm forms of P. aeruginosa (ATCC 27853) and S. aureus (ATCC 25923) strains and on Human Dermal Fibroblast (HDF) cells was investigated. Methylene blue (MB) was used as photosensitizer (0, 10, 50, 100 μg/mL). The light source was a red LED source (660 nm; power density: 20 mW/cm2) which is related to the maximum absorption of MB. The results showed that the use of saponin in combination with MB-aPDT (Methylene Blue-antibacterial photodynamic therapy) reduces the phototoxic activity of MB due to decreasing the monomer form of MB. This result was obtained by spectrophotometric study. Also, the result of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay showed that 8 min of irradiation (660 nm) at 10 μg/mL concentration of alone MB had the lowest phototoxic effect on HDF cells. Due to reduced phototoxic properties of MB in this method, detergents containing saponins not recommended to applied at the same time with MB-aPDT in wound infection area.

Saponins from Momordica charantia exert hypoglycemic effect in diabetic mice by multiple pathways

The antidiabetic activity of saponins extracted from Momordica charantia (MCS) on streptozotocin-induced diabetic mice was investigated in order to elucidate the mechanism of MCS for exerting hypoglycemic effects. Saponins were first extracted from M. charantia L. and their composition was analyzed. The diabetic Kunming mice were fed low-dose saponins from M. charantia L. and high-dose MCS, using normal mice and diabetic mice as controls. Body weight, blood glucose level, oral glucose tolerance, serum C-peptide level, hepatic antioxidant capacity, hepatic glycogen and hexokinase in liver tissues, serum blood lipid level, and alpha-glucosidase activity in small intestines were measured, and microstructure of pancreatic islet was analyzed. The results showed that the total content of seven triterpenoid compounds in MCS was 18.24 μg/mg, with Momordicoside K having the highest content at 11.66 μg/mg. Diabetic mice treated with MCS at 100 and 200 mg/kg body weight daily for 30 days showed a maximum glucose reduction (p < .05) of 12.63% and 26.47%, respectively. MCS significantly decreased levels of postprandial hyperglycemia, serum lipid, α-glucosidase activity, and liver malondialdehyde. Additionally, levels of serum C-peptide and liver glycogen, as well as hexokinase and antioxidant enzyme activity, were significantly increased compared to the diabetic control groups. Histopathological results showed that MCS markedly reduced degenerative changes in islet β-cells. It is concluded that MCS exerts antidiabetic effects by improved hypoglycemic, hypolipidemic, and antioxidant effects, increased hexokinase activity and glycogen synthesis, and enhanced reparative effects on the histological architecture and insulin secretion function of the pancreas.

Water Extract of Desalted Salicornia europaea Inhibits RANKL-Induced Osteoclast Differentiation and Prevents Bone Loss in Ovariectomized Mice

Osteoporosis, which is often associated with increased osteoclast activity due to menopause or aging, was the main focus of this study. We investigated the inhibitory effects of water extract of desalted Salicornia europaea L. (WSE) on osteoclast differentiation and bone loss in ovariectomized mice. Our findings revealed that WSE effectively inhibited RANKL-induced osteoclast differentiation, as demonstrated by TRAP staining, and also suppressed bone resorption and F-actin ring formation in a dose-dependent manner. The expression levels of genes related to osteoclast differentiation, including NFATc1, ACP5, Ctsk, and DCSTAMP, were downregulated by WSE. Oral administration of WSE improved bone density and structural parameters in ovariectomized mice. Dicaffeoylquinic acids (DCQAs) and saponins were detected in WSE, with 3,4-DCQA, 3,5-DCQA, and 4,5-DCQA being isolated and identified. All tested DCQAs, including the aforementioned types, inhibited osteoclast differentiation, bone resorption, and the expression of osteoclast-related genes. Furthermore, WSE and DCQAs reduced ROS production mediated by RANKL. These results indicate the potential of WSE and its components, DCQAs, as preventive or therapeutic agents against osteoporosis and related conditions.

Sarcocornia perennis: A Salt Substitute in Savory Snacks

Salt is the primary source of sodium in the human diet, and it is associated with hypertension and increased risk of heart disease and stroke. A growing interest in halophyte plants and food products containing this type of ingredient have been observed, to reduce the NaCl daily intake. In the present work, Sarcocornia perennis was incorporated as a food ingredient into crackers to replace the salt (NaCl) and to evaluate its impact on physical properties, water activity, nutritional composition, mineral profile, total phenolic compounds, antioxidant activity, and sensory evaluation. Concentrations of powder dried S. perennis from 1 to 10% were tested by replacing the initial salt content and adjusting the flour incorporation to the initial formulation. The incorporation of S. perennis had no relevant impact on cracker firmness, but it induced an increase in their crispness. Furthermore, the incorporation of this halophyte originated darker crackers, which was revealed by a decrease of L* and an increase of b* values. In terms of nutritional composition, the incorporation of S. perennis leads to the improvement of the snack's nutritional profile, namely in terms of phenolic compounds, antioxidant activity, and minerals, highlighting the high content in potassium, magnesium, and phosphor. Crackers with a content of 5% of S. perennis were sensorily well accepted and this level should be considered the limit of incorporation accepted by the panelists. However, by substituting 1% NaCl for an equal amount of S. perennis, it is possible to obtain a 70% reduction in sodium content, which is an important contribution to reducing the overall salt content of the diet.

Dammarane-type saponins from Gynostemma pentaphyllum and their cytotoxicities

Heat-processed Gynostemma pentaphyllum has shown strong activity against human lung carcinoma A549 cells. In this study, two dammarane-type saponins together with two known compounds were isolated from the ethanol extract of the heat-processed leaves of G. pentaphyllum. They were identified as 2α,3β,12β-trihydroxydammar-20(22),24-diene-3-O-β-D-glucopyranoside (1, namely damulin E), 2α,3β,12β-trihydroxydammar-20,24-diene-3-O-β-D-glucopyranoside (2, namely damulin F), damulin A (3) and damulin B (4), respectively, using NMR and mass spectra. Damulin E and damulin F showed moderate activity against A549, H1299, T24, SH-SY5Y and K562 cell lines in vitro using CCK-8 assay.

SARS-CoV-2 main protease inhibition by compounds isolated from Luffa cylindrica using molecular docking

In this study, chemical investigation of methanol extract of the air-dried fruits of Luffa cylindrica led to the identification of a new δ‐valerolactone (1), along with sixteen known compounds (2–17). Their chemical structures including the absolute configuration were elucidated by extensive spectroscopic analysis and electronic circular dichroism analysis, as well as by comparison with those reported in the literature. For the first time in literature, we have examined the binding potential of the isolated compounds to highly conserved protein, M^pro of SARS-CoV-2 using the molecular docking technique. We found that the isolated saponins (14–17) bind to the substrate‐binding pocket of SARS-CoV-2 M^pro with docking energy scores of –7.13, –7.29, –7.47, and –7.54 kcal.mol⁻¹, respectively, along with binding abilities equivalent to an already claimed N3 protease inhibitor (–7.51 kcal.mol⁻¹).

Chemical Structure and Biological Activities of Secondary Metabolites from Salicornia europaea L

Salicornia europaea L. is a halophyte that grows in salt marshes and muddy seashores, which is widely used both as traditional medicine and as an edible vegetable. This salt-tolerant plant is a source of diverse secondary metabolites with several therapeutic properties, including antioxidant, antidiabetic, cytotoxic, anti-inflammatory, and anti-obesity effects. Therefore, this review summarizes the chemical structure and biological activities of secondary metabolites isolated from Salicornia europaea L.

Microbial biocatalysis of quercetin-3-glucoside and isorhamnetin-3-glucoside in Salicornia herbacea and their contribution to improved anti-inflammatory activity

Salicornia herbacea (glasswort) is a traditional Asian medicinal plant which exhibits multiple nutraceutical and pharmaceutical properties. Quercetin-3-glucoside and isorhamnetin-3-glucoside are the major flavonoid glycosides found in S. herbacea. Multiple researchers have shown that flavonoid glycosides can be structurally transformed into minor aglycone molecules, which play a significant role in exerting physiological responses in vivo. However, minor aglycone molecule levels in S. herbacea are very low. In this study, Bifidobacterium animalis subsp. lactis AD011, isolated from infant feces, catalyzed >85% of quercetin-3-glucoside and isorhamnetin-3-glucoside into quercetin and isorhamnetin, respectively, in 2 h, without breaking down flavonoid backbones. Functionality analysis demonstrated that the quercetin and isorhamnetin produced showed improved anti-inflammatory activity vs. the original source molecules against lipopolysaccharide induced RAW 264.7 macrophages. Our report highlights a novel protocol for rapid quercetin and isorhamnetin production from S. herbacea flavonoids and the applicability of quercetin and isorhamnetin as nutraceutical molecules with enhanced anti-inflammatory properties.

Protective effects of mung bean (Vigna radiata L.) and pea (Pisum sativum L.) against high-fat-induced oxidative stress

Hyperlipidemia is closely related to oxidative stress, and it has been proved that the intake of legumes can protect the body from chronic diseases related to oxidative stress. In this study, we investigated the protective effects of mung beans and peas against high-fat-diet-induced rats. It was found that, with 50% addition of mung beans or peas, the intake of mung beans and peas could significantly restore the levels of serum total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol. Liver staining also showed that high-fat diet (HFD) led to liver lesions, whereas whole-grain intake could significantly relieve these symptoms. Compared with the HFD group, the antioxidant defense system and antioxidant gene expression in administered legume groups improved markedly. Furthermore, the antioxidant activities of the two legume extracts were determined. Characterization showed that the ethanol extracts of mung beans and peas possessed high antioxidant activities, for their ability to scavenge ABTS and DPPH, reduce Fe3+ and their antilipid peroxidation capacity. Treatments with ethanol extracts at different doses could restore the levels of intracellular lipid, malondialdehyde, and antioxidant enzyme activities in oleic acid-induced HepG2 cells. All these results suggested that mung beans and peas or their extracts may be utilized as good candidates of natural antioxidant agents.

Preparative mass-spectrometry profiling of minor concentrated metabolites in Salicornia gaudichaudiana Moq by high-speed countercurrent chromatography and off-line electrospray mass-spectrometry injection

Salicornia species have just been introduced to the European market as a vegetable named 'samphire', 'green asparagus', or 'sea asparagus'. Due to its increasing attention, and associated value, minor compounds of Salicornia gaudichaudiana Moq were investigated. The use of countercurrent chromatography and mass spectrometry enabled the search for known, as well as potentially novel natural products. Their identification was achieved based on molecular weights and mass-spectrometric fragmentation data. Low detection limits enabled the visualization of all compounds with their identification in almost real time close to the preparative countercurrent chromatography experiment. A list of known natural products from Salicornia genus guided the identification process of compounds occurring in Salicornia gaudichaudiana Moq by tandem mass spectrometry fragment comparison. The natural product classes were divided into four groups: chlorogenic acid derivatives; flavonoid derivatives; pentacyclic triterpenoid saponins; and other compounds.

Crude extract and solvent fractions of Calystegia soldanella induce G1 and S phase arrest of the cell cycle in HepG2 cells

The representative halophyte Calystegia soldanella (L) Roem. et Schult is a perennial vine herb that grows in coastal dunes throughout South Korea as well as in other regions around the world. This plant has long been used as an edible and medicinal herb to cure rheumatic arthritis, sore throat, dropsy, and scurvy. Some studies have also shown that this plant species exhibits various biological activities. However, there are few studies on cytotoxicity induced by C. soldanella treatment in HepG2 human hepatocellular carcinoma cells. In this study, we investigated the viability of HepG2 cells following treatment with crude extracts and four solvent-partitioned fractions of C. soldanella. Of the crude extract and four solvent fractions tested, treatment with the 85% aqueous methanol (aq. MeOH) fraction resulted in the greatest inhibition of HepG2 cell proliferation. Flow cytometry showed that the 85% aq. MeOH fraction induced a G0/G1 and S phase arrest of the cell cycle progression. The 85% aq. MeOH fraction arrested HepG2 cells at the G0/G1 phase in a concentration-dependent manner, and resulted in decreased expression of cyclin D1, cyclin E, cyclin-dependent kinase (CDK)2, CDK4, CDK6, p21, and p27. Additionally, the 85% aq. MeOH fraction treatment also arrested HepG2 cells in the S phase, with decreased expression of cyclin A, CDK2, and CDC25A. Also, treatment with this fraction reduced the expression of retinoblastoma (RB) protein and the transcription factor E2F. These results suggest that the 85% aq. MeOH fraction exhibits potential anticancer activity in HepG2 cells by inducing G0/G1 and S phase arrest of the cell cycle.

The Quality Characteristics and Antioxidant Properties of Sun-dried Venison Jerky with Green Tea Powder during Storage

This study was conducted to compare the physicochemical, microbiological and antioxidant activities of sun-dried venison amended with green tea powder (T1-3: 0, 0.5, and 1%) and Hanwoo beef jerky. Sliced beef and venison shank were marinated and sun-dried at 28-30℃ and 30-35% RH for 3.5 h. The venison jerky had a higher ash and protein content, and lower moisture and fat content than the control (p<0.05). T3 (venison+green tea powder 1%) showed a lower a_w than all other samples during storage for 10 and 20 d (p<0.05). Hunter’s color a* and b* values of T2 and T3 were lower than those of T1 and the control at day 0 (p<0.05). Saturated fatty acid was significantly higher in T1, while PUFA was higher in T2 and T3 (p<0.05). Overall sensory scores of venison jerky were lower than those of the control, except for T2, which had a similar color, flavor, saltiness and acceptability as the control. T2 and T3 showed a significant decrease in TPCs after storage for 20 d (p<0.05). The TBARS values of T3 jerky were lower than those of other jerky samples (p<0.05).

Neurobehavioral and Antioxidant Effects of Ethanolic Extract of Yellow Propolis

Propolis is a resin produced by bees from raw material collected from plants, salivary secretions, and beeswax. New therapeutic properties for the Central Nervous System have emerged. We explored the neurobehavioral and antioxidant effects of an ethanolic extract of yellow propolis (EEYP) rich in triterpenoids, primarily lupeol and β-amyrin. Male Wistar rats, 3 months old, were intraperitoneally treated with Tween 5% (control), EEYP (1, 3, 10, and 30 mg/kg), or diazepam, fluoxetine, and caffeine (positive controls) 30 min before the assays. Animals were submitted to open field, elevated plus maze, forced swimming, and inhibitory avoidance tests. After behavioral tasks, blood samples were collected through intracardiac pathway, to evaluate the oxidative balance. The results obtained in the open field and in the elevated plus maze assay showed spontaneous locomotion preserved and anxiolytic-like activity. In the forced swimming test, EEYP demonstrated antidepressant-like activity. In the inhibitory avoidance test, EEYP showed mnemonic activity at 30 mg/kg. In the evaluation of oxidative biochemistry, the extract reduced the production of nitric oxide and malondialdehyde without changing level of total antioxidant, catalase, and superoxide dismutase, induced by behavioral stress. Our results highlight that EEYP emerges as a promising anxiolytic, antidepressant, mnemonic, and antioxidant natural product.

Four New Dicaffeoylquinic Acid Derivatives from Glasswort (Salicornia herbacea L.) and Their Antioxidative Activity

Four new dicaffeoylquinic acid derivatives and two known 3-caffeoylquinic acid derivatives were isolated from methanol extracts using the aerial parts of Salicornia herbacea. The four new dicaffeoylquinic acid derivatives were established as 3-caffeoyl-5-dihydrocaffeoylquinic acid, 3-caffeoyl-5-dihydrocaffeoylquinic acid methyl ester, 3-caffeoyl-4-dihydrocaffeoylquinic acid methyl ester, and 3,5-di-dihydrocaffeoylquinic acid methyl ester. Their chemical structures were determined by nuclear magnetic resonance and electrospray ionization-mass spectroscopy (LC-ESI-MS). In addition, the presence of dicaffeoylquinic acid derivatives in this plant was reconfirmed by LC-ESI-MS/MS analysis. The isolated compounds strongly scavenged 1,1-diphenyl-2-picrylhydrazyl radicals and inhibited cholesteryl ester hydroperoxide formation during rat blood plasma oxidation induced by copper ions. These results indicate that the caffeoylquinic acid derivatives may partially contribute to the antioxidative effect of S. herbacea.

Salicornia: evaluating the halophytic extremophile as a food and a pharmaceutical candidate

Food insecurity is a major issue in current scenario where a large section of mankind is at risk of insufficient diet. As food productivity has its limits, the prospecting of unutilized or underutilized flora as food candidates is collectively recognized as a sustainable option. In the past decade, a number of obscure plants have been identified to be rich in dietary components and deemed fit for integration into the food platter. This review discusses a candidate Salicornia, belonging to family Amaranthaceae. This halophyte has a broad geographical distribution, and phytochemical profiling has indicated its food relevance. An array of functional nutrients as fibers, polyphenols, and flavonoids have been detected in Salicornia. Though high salt, oxalate and saponin content in the plants are anti-nutrients, they can be removed to justify usage of Salicornia as a ‘sea vegetable’. Apart from culinary relevance, medicinal attributes like immunomodulatory, lipid-lowering, antiproliferative, osteoprotective, and hypoglycemic render this lesser-known marsh plant significant for phytochemical studies. This appraisal is expected to be useful towards further research and popularization of this extremophile halophyte.

Adipogenesis inhibitory effects of Limonium tetragonum in mouse bone marrow stromal D1 cells

Unbalanced differentiation of bone marrow cells into adipocytes rather than osteoblasts causes severe bone-related disorders, such as osteoporosis. Natural products that can act against unbalanced differentiation are targeted for development of functional dietary supplements. Limonium tetragonum, a halophyte known for anti-oxidant constituents, was studied for beneficial effects in prevention of adipogenesis of bone marrow stromal D1 cells in vitro. Solvent-partitioned extract fractions of L. tetragonum prevented differentiating D1 cells from accumulating lipids. Expression of the key adipogenic markers PPARγ, SREBP1c, and C/EBPα were inhibited at mRNA and protein levels. Suppressed protein levels of the phosphorylated MAPK-related factors ERK, JNK, and p-38 indicated inhibition of PPARγ pathway-linked adipogenesis in D1 cells. The n-BuOH fraction was the most effective fraction for bioactive substances. L. tetragonum inhibited adipogenesis in D1 bone marrow stromal cells due to the presence of bioactive flavonoids.

Inhibition of MMP-2 and MMP-9 Activities by Limonium tetragonum Extract

Matrix metalloproteinases (MMPs) are crucial extracellular matrices degrading enzymes that take important roles in metastasis of cancer progression as well as other significant conditions such as oxidative stress and hepatic fibrosis. Natural products are on the rise for their potential to provide remarkable health benefits. In this context, halophytes have been of interest in the nutraceutical field with reported instances of isolation of bioactive compounds. In this study, Limonium tetragonum, an edible halophyte, was studied for its ability to inhibit MMP-2 and -9 using HT1080 fibrosarcoma cells. Results showed that L. tetragonum extract was able to inhibit the enzymatic activity and mRNA expression of MMP-2 and -9 according to gelatin zymography and RT-PCR assays, respectively, but it was not able to significantly change the MMP pathway related factors such as tissue inhibitors of metalloproteinases. Also, Mitogen-activated protein kinases pathway-related protein levels and their phosphorylation were assayed. While the phosphorylated p38 levels were decreased, extracellular signal-regulated kinase and c-Jun N-terminal kinase were not affected by L. tetragonum treatment. In conclusion, it was suggested that L. tetragonum contains substances acting as MMP inhibitors on enzymatic activity rather than intracellular pathway intervention, which could be useful for further utilization of L. tetragonum as a source for anti-MMP agents.

Production of novel vinegar having antioxidant and anti-fatigue activities from Salicornia herbacea L

BACKGROUND

Salicornia herbacea L. is a halophyte that grows in salt marshes and contains significant amounts of salts and minerals. Because it is known as a folk medication to treat diseases, various processed products such as powder, globular type of powder, laver and extract have been developed. However, it is difficult to process as a drink because of its high salinity. In the present study, glasswort vinegar (GV) containing high amounts of organic acids and minerals was developed via two-step fermentation with unpolished rice substrates and investigated its antioxidant and anti-fatigue activities.

RESULTS

GV showed various free radical scavenging effects, reducing power, oxidized-LDL inhibition and superoxide dismutase-like activities. Compared with the control group (orally administered 7 g kg(-1) distilled water), the GV supplementation group showed increased running endurance and had higher glycogen accumulation in liver and muscles of rats exhausted by exercise. Furthermore, the GV-administered group demonstrated significantly elevated lactate and ATP metabolism, promoting enzyme activities such as muscle creatine kinase and lactate dehydrogenase, whereas serum fatigue biomarkers such as ammonia, lactate and inorganic acid were markedly decreased.

CONCLUSION

These results indicate that GV can be used as a functional food for the development of a dietary beverage to alleviate fatigue.

Phytochemical distribution in hull and cotyledon of adzuki bean (Vigna angularis L.) and mung bean (Vigna radiate L.), and their contribution to antioxidant, anti-inflammatory and anti-diabetic activities

Total saponin content, total phenolics content, total flavonoids content, condensed tannin content in hull, cotyledon and whole grain of both adzuki bean and mung bean were determined by colorimetric methods. Vitexin and isovitexin contents in mung bean were determined by HPLC. Antioxidant effects were evaluated with DPPH scavenging activity and ferric reducing antioxidant power assay. In vitro anti-inflammatory and anti-diabetic effects of beans were evaluated by protease and aldose reductase inhibitory assays, respectively. The results indicated that the bean hulls were the most abundant in phytochemicals and largely contributed antioxidant activities, anti-inflammatory effects and anti-diabetic effects of whole grains. The result showed that mung bean hull was the most abundant with vitexin at 37.43 mg/g and isovitexin at 47.18 mg/g, respectively. Most of the phytochemicals and bioactivities were most predominantly contributed by the bean hulls with exception for condensed tannin of mung bean; which was more abundant in the cotyledon than its hull.

Flavanones and Chromones from Salicornia herbacea Mitigate Septic Lethality via Restoration of Vascular Barrier Integrity

Salicornia herbacea is an annual halophytic glasswort that has been employed as a culinary vegetable, salad, and traditional medicinal resource. Chemical investigation of the aerial parts of S. herbacea led to the isolation of two new (1, 2) and known (3) flavanones as well as a new nature-derived (4) and two known chromone derivatives (5, 6). These purified compounds were evaluated for their suppressive potentials against the release of high-mobility group box 1 protein (HMGB1), which has captured attention as a viable target for alleviating serious septic manifestations or septicemia. The phenolic compounds improved the survival rates of cecal ligation and puncture operation (CLP) in murine models, simulating severe septic shock and its related complications, to 40-60%. These results collectively validate that flavanone- and chromone-based secondary metabolites may serve as prospective prodrugs or food additives that may be commercialized for the control of septic complications and lethality.

Triterpenoids from the Herbs of Salicornia bigelovii

A new nortriterpene saponin, 3-O-β-d-glucuronopyranosyl-30-norolean-12,20(29)-dien-23- oxo-28-oic acid, namely bigelovii D (11), was isolated from the hydroalcoholic extract of herbs of Salicornia bigelovii along with 10 known saponins (1-10). Their chemical structures were identified on the basis of spectroscopic analyses including two-dimensional NMR and a comparison with literature data. Some of these compounds showed potent antifungal activities in vitro. Compounds 3, 4, 5, 6, 7, 10 and 11 demonstrated potent inhibitory activities against Colletotrichum gloeosporioides and compound 11 displayed broad-spectrum inhibitory activity against Alternaria alternata, A. solani, Botrytis cinerea, C. gloeosporioides, Fusarium graminearum, F. verticilloides, Thanatephorus cucumeris and Sclerotinia sclerotiorum, with EC50 values ranging from 13.6 to 36.3 μg/mL.

Isolation, identification and cytotoxicity of a new noroleanane-type triterpene saponin from Salicornia bigelovii Torr

Salicornia bigelovii Torr. has been consumed not only as a popular kind of vegetable, but also as a medicinal plant to treat hypertension, cephalalgia, scurvy and cancer. The present study was designed to investigate its chemical components and cytotoxic activity. A new noroleanane-type triterpene saponin, bigelovii C (1), was separated and purified from Salicornia bigelovii Torr., along with four known triterpene saponins 2-5. The structure of bigelovii C was elucidated as 3-O-(6-O-butyl ester)-β-D-glucuropyranosyl-23-aldehyde-30-norolean-12, 20 (29)-dien-28-oic acid-28-O-β-D-glucopyranoside, according to various spectroscopic analysis and chemical characteristics. Besides Compounds 3 and 5, bigelovii C had potent cytotoxicity against three human cancer cell lines, MCF7 (breast cancer), Lovo (colon cancer) and LN229 (glioblastoma), especially MCF7. Bigelovii C inhibited the growth of MCF7 cells in dose- and time-dependent manners. Flow cytometry analysis revealed that the percentage of apoptotic cells significantly increased upon bigelovii C treatment. Rh123 staining assay indicated that bigelovii C reduced the mitochondrial membrane potential. The mechanism of cell death by bigelovii C may be attributed to the downregulation of Bcl-2 and upregulation of Bax, cleaved caspase-9, caspase-7 and PARP. These results suggested that bigelovii C may impart health benefits when consumed and should be regarded as a potential chemopreventative agent for cancer.

Solvent system selectivities in countercurrent chromatography using Salicornia gaudichaudiana metabolites as practical example with off-line electrospray mass-spectrometry injection profiling

For the development of an efficient two-stage isolation process for high-speed countercurrent chromatography (HSCCC) with focus on principal metabolites from the ethyl acetate extract of the halophyte plant Salicornia gaudichaudiana, separation selectivities of two different biphasic solvent systems with similar polarities were evaluated using the elution and extrusion approach. Efficiency in isolation of target compounds is determined by the solvent system selectivity and their chronological use in multiple separation steps. The system n-hexane-ethyl acetate-methanol-water (0.5:6:0.5:6, v/v/v/v) resulted in a comprehensive separation of polyphenolic glycosides. The system n-hexane-n-butanol-water (1:1:2, v/v/v) was less universal but was highly efficient in the fractionation of positional isomers such as di-substituted cinnamic acid quinic acid derivatives. Multiple metabolite detection performed on recovered HSCCC tube fractions was done with rapid mass-spectrometry profiling by sequential off-line injections to electrospray mass-spectrometry (ESI-MS/MS). Selective ion traces of metabolites delivered reconstituted preparative HSCCC runs. Molecular weight distribution of target compounds in single HSCCC tube fractions and MS/MS fragment data were available. Chromatographic areas with strong co-elution effects and fractions of pure recoverable compounds were visualized. In total 11 metabolites have been identified and monitored. Result of this approach was a fast isolation protocol for S. gaudichaudiana metabolites using two solvent systems in a strategic sequence. The process could easily be scaled-up to larger lab-scale or industrial recovery.

Triterpenoids

This review covers the isolation and structure determination of triterpenoids reported during 2012 including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes, isomalabaricanes and saponins; 348 references are cited.

21-O-angeloyltheasapogenol E3, a novel triterpenoid saponin from the seeds of tea plants, inhibits macrophage-mediated inflammatory responses in a NF-κB-dependent manner

21-O-Angeloyltheasapogenol E3 (ATS-E3) is a triterpenoid saponin recently isolated from the seeds of the tea tree Camellia sinensis (L.) O. Kuntze. ATS-E3 has several beneficial properties including anti-inflammatory, antidiabetic, antiatherosclerotic, and anticancer effects. Unlike other phenolic compounds isolated from tea plants, there are no studies reporting the pharmacological action of ATS-E3. In this study, we therefore aimed to explore the cellular and molecular inhibitory activities of ATS-E3 in macrophage-mediated inflammatory responses. ATS-E3 remarkably diminished cellular responses of macrophages such as FITC-dextran-induced phagocytic uptake, sodium nitroprusside- (SNP-) induced radical generation, and LPS-induced nitric oxide (NO) production. Analysis of its molecular activity showed that this compound significantly suppressed the expression of inducible NO synthase (iNOS), nuclear translocation of nuclear factor- (NF-) κB subunits (p50 and p65), phosphorylation of inhibitor of κB kinase (IKK), and the enzyme activity of AKT1. Taken together, the novel triterpenoid saponin compound ATS-E3 contributes to the beneficial effects of tea plants by exerting anti-inflammatory and antioxidative activities in an AKT/IKK/NF-κB-dependent manner.

Novel dammarane saponins from Gynostemma pentaphyllum and their cytotoxic activities against HepG2 cells

Two new dammarane saponins, 2α,3β,12β-trihydroxydammar-20(22),24-diene-3-O-[β-D-glucopyranoxyl(1→2)-β-D-6″-O-acetylglucopyranoside (1, namely damulin C) and 2α,3β,12β-trihydroxydammar-20(21),24-diene-3-O-[β-D-glucopyranoxyl(1→2)-β-D-6″-O-acetylglucopyranoside (2, namely damulin D), were isolated from the ethanol extract of Gynostemma pentaphyllum, which had been heat processed by steaming at 125 °C. The NMR spectroscopic data of the novel saponins were completely assigned by using a combination of 2D NMR experiments including (1)H-(1)H COSY, HSQC, and HMBC. Their cytotoxic activities of human liver adenocarcinoma HepG2 cells were evaluated in vitro. They showed cytotoxicities against HepG2 cell line with IC50 of 40±0.7 and 38±0.5 μg/ml, respectively.

Two new noroleanane-type triterpene saponins from the methanol extract of Salicornia herbacea

Two new noroleanane-type triterpene saponins, Salbige A (1) and Salbige B (2), have been isolated from the aerial parts of Salicornia herbacea together with five other known compounds, including echinocystic acid (3), gypsogenin (4), pheophorbide a (5), (13(2)S)-hydroxy-pheophorbide a (6) and (13(2)S)-hydro-pheophorbide-lactone a (7). The chemical structures of these compounds were elucidated by extensive spectroscopic analysis and on the basis of their chemical reactivity. This work represents the first recorded example of the isolation of these compounds from S. herbacea. Compounds 1 and 2 exhibited potent antiproliferative activities and high levels of selectivity towards A549 cancer cells, with IC50 values of 52.35 and 79.39 μM, respectively, whereas compound 5 showed high levels of inhibitory activity against A549 and HepG2 cancer cells with IC50 values of 6.15 and 17.56 μM, respectively. None of these compounds exhibited antioxidant activities except for compound 7, which showed weak antioxidant activity.

Dammarane-type saponins from heat-processed Gynostemma pentaphyllum show fortified activity against A549 cells

An ethanol extract from heat-processed Gynostemma pentaphyllum showed more potent cytotoxic activity against human lung adenocarcinoma A549 cells than that of raw G. pentaphyllum. Four constituents were isolated from heat-processed G. pentaphyllum using resin HP-20, silica gel and reversed ODS column chromatography. They were identified by mass and NMR spectra as damulin A and damulin B, gypenoside L and gypenoside LI, respectively. To evaluate the efficacy of these four constituents, the MTT cytotoxicity assay was performed using A549 cells. Based on the structure of these four constituents, the results indicate that the hydroxyl group in C-2 and double bond in C20(21) and C20(22) positions are of importance in inhibition of A549 cell proliferation.

Pentadecyl ferulate, a potent antioxidant and antiproliferative agent from the halophyte Salicornia herbacea

An investigation of the chemical constituents of Salicornia herbacea has led to the isolation of one new natural product, pentadecyl ferulate (6), together with 11 known compounds, including phytol (1), stearolic acid (2), γ-linolenic acid (3), (3Z,6Z,9Z)-tricosa-3,6,9-triene (4), linoleic acid (5), stigmasterol (7), ergosterol (8), dioctyl phthalate (9), dibutyl phthalate (10), vanillic aldehyde (11), and scopoletin (12). The chemical structures of these materials were elucidated mainly by spectroscopic analysis. This work represents the first recorded example of the isolation of compounds 1, 2, 3, 4, 9, 10, and 11 from S. herbacea. The antioxidant experiments revealed that compound 6 possessed strong hydroxy radical and superoxide anion scavenging activities and was the principle antioxidant ingredient in the ethyl acetate extract. The antiproliferative results exhibited that compound 1 selectively inhibited HepG2 cells, whereas compounds 3 and 6 showed potent antiproliferative activities against HepG2 and A549 cells.