The potential anti-Alzheimer's activity of Oxalis corniculata Linn. Methanolic extract in experimental rats: Role of APOE4/LRP1, TLR4/NF-κß/NLRP3, Wnt 3/ß-catenin/GSK-3ß, autophagy and apoptotic cues.

ETHNOPHARMACOLOGICAL RELEVANCE: Oxalis corniculata (O. corniculata) is a member of Oxalidaceae family, widely distributed in Asia, Europe, America, and Africa, used extensively as food and its traditional folkloric uses include management of epilepsy, gastric disorders, and neurodegenerative diseases, together with its use in enhancing health. Numerous pharmacological benefits of O. corniculata are linked to its anti-inflammatory and antioxidant abilities. One of the most prevalent neurodegenerative disorders is Alzheimer's disease (AD) in which neuroinflammation and oxidative stress are its main pathogenic processes. AIM OF THE STUDY: Our research aimed to study the neuroprotective effect of the methanolic extract of Oxalis corniculata Linn. (O. corniculata ME), compared to selenium (Se) against AlCl3-induced AD. MATERIALS AND METHODS: Forty male albino rats were allocated into four groups (Gps). Gp I a control group, the rest of the animals received AlCl3 (Gp II-Gp IV). Rats in Gp III and IV were treated with Se and O. corniculata ME, respectively. RESULTS: The chemical profile of O. corniculata ME was studied using ultraperformance liquid chromatography-electrospray ionization-quadrupole time-of-flight mass spectrometry, allowing the tentative identification of sixty-six compounds, including organic acids, phenolics and others, cinnamic acid and its derivatives, fatty acids, and flavonoids. AlCl3 showed deterioration in short-term memory and brain histological pictures. Our findings showed that O. corniculata ME and selenium helped to combat oxidative stress produced by accumulation of AlCl3 in the brain and in prophylaxis against AD. Thus, Selenium (Se) and O. corniculata ME restored antioxidant defense, via enhancing Nrf2/HO-1 hub, hampered neuroinflammation, via TLR4/NF-κß/NLRP3, along with dampening apoptosis, Aß generation, tau hyperphosphorylation, BACE1, ApoE4 and LRP1 levels. Treatments also promoted autophagy and modulated Wnt 3/ß-catenin/GSK3ß cue. CONCLUSIONS: It was noted that O. corniculata ME showed a notable ameliorative effect compared to Se on Nrf2/HO-1, TLR4/NF-κß/NLRP3, APOE4/LRP1, Wnt 3/ß-catenin/GSK-3ß and PERK axes.

A Review on Phyto-pharmacology of Oxalis corniculata.

Oxalis corniculata (Oxalidaceae) is a small decumbent and delicate appearing medicinal herb flourishing in warm temperate and tropical domains such as Pakistan and India. Main bioactive chemical constituents of Oxalis plant include several alkaloids, flavonoids, terpenoids, cardiac glycosides, saponins, and phlobatannins, along with steroids. Due to its polyphenolic, glycosides and flavonoid profile, it is proved to be protective in numerous ailments and exhibit various biological activities such as anti-fungal, anti-cancer, anti-oxidant, antibacterial, anti-diabetic, and cardioprotective. Moreover, bioactive phytochemicals from this plant possess significant wound healing potential. Our current effort intends to emphasize on the immense significance of this plant species, which have not been the subject matter of clinical trials and effective pharmacological studies, even though its favored usage has been stated. This review proposes that Oxalis corniculata possess a potential for the cure of various diseases. However, further researches on isolation and characterization of bioactive compounds along with pre-clinical trials are compulsory to figure out its pharmacological applications.

Antibacterial Potency of Medicinal Plants including Artemisia annua and Oxalis corniculata against Multi-Drug Resistance E. coil.

Antibacterial activity of ethanolic and aqueous extracts of two medicinal plants including Oxalis corniculata (EtOc, AqOc) and Artemisia annua (EtAa, AqAa) as well as A. annua essential oil (EoAa) was investigated on multi-drug resistance (MDR) E. coli. Microdilution and agar well diffusion methods were used to determine the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) as well as the inhibition zone. The phytconstituents of these products were analyzed using Reverse-phase High- performance liquid chromatography (RP-HPLC) and gas chromatography-mass spectrometry (GC-mass). The order of bacteriostatic and bacteriocide rate of the products can be shown as follows: EoAa>AqOc>EtAa = AqAa>EtOc, but the bactericidal effect of A. annua extracts is higher than of O. corniculata based on the MIC/MBC ratio and the order is as follows: EoAa>EtAa = AqAa>EtOc>AqOc. The most potent product, i.e. EoAa with a 56.7% inhibition of all isolates, has the potential to substitute 13 used antibiotics including oxacillin, amoxicillin, ampicillin, amoxicillin-clavulanic acid, tetracycline, streptomycin, ciprofloxacin, ceftriaxone, cefazolin, cefuroxime, cefotaxime, ceftazidime and cefixime (P <0.05). Different terpenoids were detected and measured in EoAa and catechin flavonoids in extracts of both plants, quercetin in extracts of O. corniculata but it was only possible to detect chlorogenic acid polyphenol in AqAa. Due to the antibacterial activities of the studied products, more effective than some antibiotics and their edible consumption, these products can be suggested as an alternative to some antibiotics and food preservatives to fight against MDR E. coli.

Invasive Plants: Turning Enemies into Value.

In this review, a brief description of the invasive phenomena associated with plants and its consequences to the ecosystem is presented. Five worldwide invasive plants that are a threat to Portugal were selected as an example, and a brief description of each is presented. A full description of their secondary metabolites and biological activity is given, and a resume of the biological activity of extracts is also included. The chemical and pharmaceutical potential of invasive species sensu lato is thus acknowledged. With this paper, we hope to demonstrate that invasive species have potential positive attributes even though at the same time they might need to be controlled or eradicated. Positive attributes include chemical and pharmaceutical properties and developing these could help mitigate the costs of management and eradication.

A sustainable approach for graphene-oxide surface decoration using Oxalis corniculata leaf extract-derived silver nanoparticles: their antibacterial activities and electrochemical sensing.

In this work, a facile green synthesis using Oxalis corniculata leaf extract (OCLE) as a biodegradable reducing and capping/stabilizing agent was carried out for the construction of Oxalis corniculata leaf extract-derived silver nanoparticles (OCLE-AgNPs). Moreover, OCLE-AgNPΔGO nanocomposites were fashioned simply by mixing a GO suspension and supernatant OCLE-AgNPs via a one-pot environmentally benign method. The AgNPΔGO nanocomposites are biocompatible materials for potential applications such as antibacterial activities against two different types of bacterial cells, namely Gram-positive Bacillus subtilis and Gram-negative Escherichia coli and selective electrochemical sensing to itraconazole (ITRA) at the fabricated GCE (AgNPΔGO@GCE). AgNPΔGO@GCE sensors gave excellent outcomes for ITRA as higher current response over the bare GCE. Under optimized conditions, the oxidation peak current of ITRA varied linearly with a wide range of the concentration between 26.7 µM and 103.8 µM with a correlation coefficient of 0.997 and a detection limit of 0.1276 µM, for differential pulse anodic stripping voltammetric (DP-ASV) technique. In addition, the possible mechanism for the ITRA oxidation was further verified and explained by single-electron transfer (SET) and proton removal mechanism steps. The developed sensor exhibited good repeatability, reproducibility, and stability. The use of environmentally benign and renewable plant material offers enormous benefits of eco-friendliness applicability.

LC-ESI-QTOF-MS for the Profiling of the Metabolites and in Vitro Enzymes Inhibition Activity of Bryophyllum pinnatum and Oxalis corniculata Collected from Ramechhap District of Nepal.

The objective of this study was to profile the chemical components and biological activity analysis of crude extract of Bryophyllum pinnatum and Oxalis corniculata. Results revealed that the analyzed plant materials encompass the high amount of total phenolic and flavonoids content and have significant antioxidant activities. Furthermore, methanol extracts are the potential source of α-amylase, α-glucosidase, lipase, tyrosinase and elastase inhibitors. High resolution mass spectrometry revealed the presence of diverse metabolites such as quercetin 3-O-α-L-rhamnopyranoside, myricetin 3-rhamnoside, bersaldegenin 1,3,5-orthoacetate, bryophyllin C, syringic acid, caffeic acid, p-coumaric acid, and quercetin in B. pinnatum and isoorientin, swertisin, apigenin 7,4'-diglucoside, vitexin, 4-hydroxybenzoic acid, vanillic acid, ethyl gallate, 3,3',4'-trihydroxy-5,7-dimethoxyflavone, and diosmetin-7-O-ß-D-glucopyranoside in O. corniculata. Our finding suggested that these two plant species have high medicinal importance and are potential source of inhibitors for modern pharmaceuticals, nutraceuticals and cosmetics industries.

Comparison of physicochemical properties of oca (Oxalis tuberosa), potato, and maize starches.

Oca (Oxalis tuberosa) represents a novel source of starch. Starches from the tubers of two commercial oca varieties were studied for various physicochemical properties. One normal potato starch and one normal maize starch were used for comparison. Oca starches showed lower gelatinization temperatures compared to both potato and maize starches. The pasting, flow, and gelation behaviors of oca starches were intermediate between potato and maize starches. Oca starch pastes were more viscous than maize starch paste and more elastic than potato starch paste. The differences in the properties could be largely due to lower amylose content, intermediate contents of phosphate groups (~400 ppm) and granule size (34.6 µm) of oca starches as compared to the other two starches. The internal unit chains of amylopectin such as the amount of fingerprint B-chains and length of B-chains could also partially explain the different physicochemical properties among oca, potato and maize starches.

Vascular effects of a polyphenolic fraction from Oxalis pes-caprae L.: role of α-adrenergic receptors Sub-types.

Oxalis pes-caprae L. is a plant of the Oxalidaceae family, from which several compounds have been previously identified. Recently, we showed that an Oxalis pes-caprae L. extract inhibits the vasopressor effect of noradrenaline. In this work we aimed to explore the mechanisms involved in this effect. The results confirmed that the flavonoid fraction present in the extract inhibits noradrenaline-induced contractions and that this effect is concentration-dependent. Also, a parallel shift to the right in the noradrenaline concentration-response curve was observed, suggesting a decrease in efficacy and also in potency. Together these results support the assumption that the extract could exert a non-competitive antagonism on the α-adrenergic receptors. However, experiments in the presence of competitive antagonists for α-adrenergic receptor sub-types (i.e. prazosin, yohimbine and phentolamine) showed that the effect may not be directly mediated by α-adrenergic receptors. Thus, the interaction of this extract with the adrenergic system remains to be confirmed.

Extract of Averrhoacarambola L. (Oxalidaceae) roots ameliorates carbon tetrachloride-induced hepatic fibrosis in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The root of Averrhoa carambola L. (Oxalidaceae), a traditional Chinese medicine, was mainly used in ancient times in the treatment of urinary calculi, recurrent headache and joint pain. AIM OF THE STUDY: Our aims were to explore the potential therapeutic effect of the extract of Averrhoa carambola L. (Oxalidaceae) roots (EACR) against hepatic fibrosis in CCl4-treated rats and to understand the underlying molecular mechanism. MATERIALS AND METHODS: Six groups of male Sprague Dawley rats were treated as follows: vehicle (olive oil), CCl4 alone, CCl4+colchicine, CCl4+EACR 1.0 g/kg, CCl4+EACR 0.5 g/kg and CCl4+EACR 0.25 g/kg. At the end of the 12th week, biomarkers of liver function, liver fibrosis, hepatic oxidative stress and antioxidant status were assayed, and histopathological and immunohistochemical evaluation of liver tissue were conducted to investigate the liver damage and fibrosis degree. Furthermore, expressions of COL-1a1, α-SMA, TGF-ß1, Smad2, smad3, Smad4 and TIMP2 were examined by qPCR and/or western blot. The expressions of apoptosis-related proteins were also detected using western blot analysis. RESULTS: EACR treatment markedly reduced the CCl4-induced elevation of serum aminotransferase activities, liver fibrosis indexes, and the extent of oxidative stress. EACR treatment also significantly reduced the accumulation of collagen and the immunostaining of α-SMA, TGF-ß1 and Smad2, 4 and 7 in the liver of CCl4 treated rats. In addition, EACR treatment markedly reversed the CCl4-induced increase in mRNA expression of COL-1a1, α-SMA, TIMP2, TGF-ß1, Smad2 and Smad4 and suppressed the expressions of α-SMA, TIMP2, TGF-ß1, smad2, 3 and 4, BAX and cleaved caspase-3 proteins. Meanwhile, EACR treatment also significantly elevated the mRNA expression of Smad7 and the protein expression of Smad7 and Bcl-2. CONCLUSION: These results suggest that EACR has protective activity against liver fibrosis. The anti-fibrotic activity of EACR in vivo is associated with enhanced antioxidant, apoptosis-inhibition and increased MMP-2/TIMP-2 expression ratio, and with modulation of TGF-ß1/Smad signaling pathway.

Antibacterial and In Vitro Growth Inhibition Study of Struvite Urinary Stones Using Oxalis corniculata Linn. Leaf Extract and its Biofabricated Silver Nanoparticles.

BACKGROUND: Herbal drugs are gaining exponential scientific recognition due to their distinct advantages. In the last 2-3 decades, a gradual increase in worldwide patents on herbal nanoformulations has been noted to address the solubility and bioavailability issues of phytoceuticals. Struvite or ammonium magnesium phosphate hexahydrate (NH4MgPO4.6H2O) is among the important urinary infection stones causing painful urological ailment. These smaller stones may bind together to form bigger staghorn calculus. Urinary tract infections caused by some gram positive and gram negative bacteria further enhance the chance of formation of such stones. Oxalis corniculata Linn. is an edible plant, traditionally used in the treatment of bacterial infections and kidney stones. However, there is no scientific evidence to relate the use of O. corniculata against struvite kidney stones. Hence, the antibacterial and struvite stones inhibition activity of the aqueous extract of Oxalis corniculata Linn. leaves and its biofabricated silver nanoparticles (AgNPs) was studied. METHODS: The aqueous extract of O. corniculata was prepared by Soxhlet extraction. AgNPs were synthesized using green technique and were characterized using UV and IR spectroscopy, XRD, TEM, DLS and zeta potential studies. Antibacterial activity of the aqueous extract and the silver nanoparticles was tested against E. coli (gram negative) and S. aureus (gram positive) species. Struvite stones were grown in a gel medium by in vitro single diffusion gel growth technique and its inhibition study was carried out using the extract and its biofabricated nanoparticles. RESULTS: The aqueous extract and its biofabricated AgNPs exhibited potent antibacterial activity against both gram positive and gram negative strains of bacteria. The aqueous extract also effectively repressed the growth of struvite stones and led to the dissolution of stones, but the inhibitory effect was further enhanced by its biofabricated AgNPs. CONCLUSION: The present work confirms the inhibitory activity of the aqueous extract of edible O. corniculata and its biofabricated silver nanoparticles against urinary tract infection (UTI) causing bacteria and urolithiasis. Therefore, the consumption of O. corniculata in our daily diet may reduce the risk of UTI and urolithiasis.

Polyphenolic characterisation and bioactivity of an Oxalis pes-caprae L. leaf extract.

The present work is focused on the characterisation of the polyphenolic content of an Oxalis pes-caprae L. leaf extract and on the evaluation of its bioactivity with particular interest on its vascular activity and antioxidant potential. The polyphenolic content was characterised by HPLC-DAD and LC-MS/MS. The vascular activity was evaluated according to the influence on the serotonergic and adrenergic systems of the human internal mammary artery (HIMA). Antioxidant and neuroprotective studies were also conducted. Several luteolin and apigenin derivatives were identified as main constituents of the extract, which did not present any contractile effect nor had any effect on the serotonergic system of HIMA. However, it showed antagonistic effect on the adrenergic system, inhibiting the contraction to noradrenaline (reduction of 58.44% of maximum contraction). The extract showed antioxidant activity and standardised luteolin and apigenin derivatives showed neuroprotective potential, particularly homoorientin.

In vitro larvicidal and in vivo anthelmintic effects of Oxalis tetraphylla (Oxalidaceae) hydroalcoholic extract against Haemonchus contortus in lambs.

The in vitro larvicidal and in vivo anthelmintic effects of Oxalis tetraphylla hydroalcoholic extract (HE), against Haemonchus contortus in experimentally infected lambs, were assessed. We used a microtitration plate method, comprising the following two stages. Stage 1: 20 µl of water containing 200 sheathed H. contortus infective larvae (ShHcl) were deposited in every well of three series; then, the series 2 and 3 wells were treated with 80 µl 1% ivermectin and O. tetraphylla HE at 20 mg/ml, respectively. Stage 2: the same procedure was performed replacing the ShHcl with exsheathed larvae (ExShHcl). Evaluations were performed after 24 and 48 h. The total numbers of dead and live larvae were counted. A second experiment evaluated the reduction in nematode egg populations in the faeces of lambs treated orally with the O. tetraphylla HE. The 27 lambs used were divided into Groups 1, 2 and 3 (n = 9), which were administered water (positive control), levamisole 1 m (7.5 mg/kg body weight (BW), as a unique dose) and O. tetraphylla HE (20 mg/kg BW), respectively. The plant HE was administered daily for 8 days. The in vitro assay showed 80.9% and 86.5% larval mortality of ShHcl after 24 and 48 h, respectively, while the corresponding mortality values for ExShHcl were 97 and 99%, respectively. The in vivo assay showed variability in the eggs/gram of faeces (epg) values; however, at the end of the trial, the average reduction in the epg values of the O. tetraphylla HE group was 45.6% (P < 0.05). Oxalis tetraphylla HE contains compounds that belong to the flavonol group with anthelmintic activity.

Unexpected formation of gold nanoflowers by a green synthesis method as agents for a safe and effective photothermal therapy.

Star fruit (Averrhoa carambola) juice rich in vitamin C and polyphenolic antioxidants was used to synthesize branched gold nanoflowers. These biocompatible and stable gold nanoflowers show strong near-infrared absorption. They are successfully demonstrated to be highly efficient for both in vitro and in vivo photothermal therapy by using an 808 nm laser.

Biological and life table parameters of Typhlodromus laurentii and Iphiseius degenerans (Acari, Phytoseiidae) fed on Panonychus citri and pollen of Oxalis pes-caprae under laboratory conditions.

Typhlodromus laurentii and Iphiseius degenerans are two generalist phytoseiid mites, broadly spread in the Mediterranean area, especially in citrus orchards. In the present work we report results on various biological and life table parameters of the two phytoseiids, fed on pollen of Oxalis pes-caprae and various stages of the tetranychid Panonychus citri. Iphiseius degenerans had the shortest post embryonic development (6.53 days), the highest oviposition rate (1.83 eggs/female/day) and the shortest mean time between eggs laid (0.55 day) on Oxalis pollen, whereas the two food types did not influence these parameters in T. laurentii. However, Oxalis pollen showed a positive effect on the survivorship of the latter phytoseiid, with a median life time (LT50) of 44.51 days, which was two times longer than that registered on prey with the same phytoseiid, and on both food types with I. degenerans. This latter species had a better performance on the pollen (rm = 0.243, λ = 1.275, Ro = 22.88, DT = 2.85) than on prey (rm = 0.182, λ = 1.199, Ro = 17.43, DT = 3.81). On the other hand, the pollen influenced the net reproductive rate (25.43 females/female) of T. laurentii positively but showed the same effect as the prey on the other demographic parameters. Our results improve knowledge on the feeding behaviour of the above mentioned phytoseiids on two food sources that could represent the main possibility to maintain a consistent population of these predators during winter. Moreover, both phytoseiids were shown to be good biocontrol candidates of P. citri populations.

Antiplasmodial, anti-complement and anti-inflammatory in vitro effects of Biophytum umbraculum Welw. traditionally used against cerebral malaria in Mali.

ETHNOPHARMACOLOGICAL RELEVANCE: Biophytum umbraculum Welw. (Oxalidaceae) is a highly valued African medicinal plant used for treatment of cerebral malaria, a critical complication of falciparum malaria. AIM OF THE STUDY: To provide additional information about traditional use of B. umbraculum and to test plant extracts and isolated compounds for in vitro activities related to cerebral malaria. MATERIALS AND METHODS: The traditional practitioners were questioned about indication, mode of processing/application, dosage and local name of B. umbraculum. Organic extracts and some main constituents of the plant were investigated for anti-malaria, anti-complement activity and inhibition of NO secretion in a RAW 264.7 cell line. RESULTS: Treatment of cerebral malaria was the main use of B. umbraculum (fidelity level 56%). The ethyl acetate extract showed anti-complement activity (ICH50 5.7±1.6µg/ml), inhibition of macrophage activation (IC50 16.4±1.3µg/ml) and in vitro antiplasmodial activity (IC50 K1 5.6±0.13µg/ml, IC50 NF54 6.7±0.03µg/ml). The main constituents (flavone C-glycosides) did not contribute to the activity of the extract. CONCLUSION: Inhibition of complement activation and anti-inflammatory activity of B. umbraculum observed in this study might be possible targets for adjunctive therapy in cerebral malaria together with its antiplasmodial activity. However, clinical trials are necessary to evaluate the activity due to the complex pathogenesis of cerebral malaria.

Anticancer activity of Cynodon dactylon and Oxalis corniculata on Hep2 cell line.

Bioactive chemicals isolated from plants have attracted considerable attention over the years and overwhelmingly increasing laboratory findings are emphasizing on tumor suppressing properties of these natural agents in genetically and chemically induced animal carcinogenesis models. We studied in vitro anticancer activity of organic extracts of Cynodon dactylon and Oxalis corniculata on Hep2 cell line and it was compared with normal human corneal epithelial cells (HCEC) by using MTT assay. Real Time PCR was conducted for p53 and PTEN genes in treated cancer cell line. DNA fragmentation assay was also carried out to note DNA damaging effects of the extracts. The minimally effective concentration of ethanolic extract of Cynodon dactylon and methanolic extract of Oxalis corniculata that was nontoxic to HCEC but toxic to Hep2 was recorded (IC50) at a concentration of 0.042mg/ml (49.48 % cell death) and 0.048mg/ml (47.93% cell death) respectively, which was comparable to the positive control. Our results indicated dose dependent increase in cell death. P53 and PTEN did not show significant increase in treated cell line. Moreover, DNA damaging effects were also not detected in treated cancer cell line. Anticancer activity of these plants on the cancer cell line showed the presence of anticancer components which should be characterized to be used as anticancer therapy.

Antioxidant films based on cross-linked methyl cellulose and native Chilean berry for food packaging applications.

Development of antioxidant and antimicrobial active food packaging materials based on biodegradable polymer and natural plant extracts has numerous advantages as reduction of synthetic additives into the food, reduction of plastic waste, and food protection against microorganisms and oxidation reactions. In this way, active films based on methylcellulose (MC) and maqui (Aristotelia chilensis) berry fruit extract, as a source of antioxidants agents, were studied. On the other hand, due to the high water affinity of MC, this polymer was firstly cross-linked with glutaraldehyde (GA) at different concentrations. The results showed that the addition of GA decreased water solubility, swelling, water vapor permeability of MC films, and the release of antioxidant substances from the active materials increased with the concentration of GA. Natural extract and active cross-linked films were characterized in order to obtain the optimal formulation with the highest antioxidant activity and the best physical properties for latter active food packaging application.

High-resolution hyaluronidase inhibition profiling combined with HPLC-HRMS-SPE-NMR for identification of anti-necrosis constituents in Chinese plants used to treat snakebite.

Inhibition of the necrotizing hyaluronidase, phospholipase A2 and protease enzymes in four snake venoms by crude water and ethanol extracts of 88 plant species used against snakebites in traditional Chinese medicine was measured. High-resolution hyaluronidase inhibition profiles were constructed for the 22 plants showing highest hyaluronidase inhibition, and the results were used to guide subsequent structural analysis towards specific hyaluronidase inhibitors. Structural analysis was performed by high-performance liquid chromatography, high-resolution mass spectrometry, solid-phase extraction and nuclear magnetic resonance spectroscopy, i.e., HPLC-HRMS-SPE-NMR. This allowed identification of four non-tannin inhibitors, i.e., lansiumamide B (6) from Clausena excavata Burm.f., myricetin 3-O-ß-D-glucopyranoside (7) from Androsace umbellata (Lour.) Merr., and vitexin (8) and 4',7-dihydroxy-5-methoxyflavone-8-C-ß-D-glucopyranoside (9) from Oxalis corniculata L. Absolute configuration of 2,3-dihydroxy-N-methyl-3-phenyl-N-[(Z)-styryl]propanamide (1) was determined using the Mosher method, which revealed two enantiomers, i.e., (2S,3R)-2,3-dihydroxy-N-methyl-3-phenyl-N-[(Z)-styryl]propanamide and (2R,3S)-2,3-dihydroxy-N-methyl-3-phenyl-N-[(Z)-styryl]propanamide with a ratio of 7:3.

Effect of the Total Extract of Averrhoacarambola (Oxalidaceae) Root on the Expression Levels of TLR4 and NF-κB in Streptozotocin-Induced Diabetic Mice.

BACKGROUND: Averrhoacarambola L., which is a folk medicine used in diabetes mellitus (DM) in ancient China, has been reported to have anti-diabetic efficacy. AIMS: The aim of this study was to evaluate the hypoglycemic effect of the extract of Averrhoacarambola L. root (EACR) on the regulation of the Toll-like receptor 4 (TLR4)-Nuclear-factor kappa B (NF-κB) pathway in B) pathway in streptozotocin (STZ)-induced diabetic mice. METHODS: the mice were injected with STZ (120 mg/kg body weight) via a tail vein. After 72 h, the mice with FBG ≥ 11.1 mmol/L were confirmed as having diabetes. Subsequently, the mice were treated intragastrically with EACR (300, 600, 1200 mg/kg body weight/d) and metformin (320 mg/kg body weight/d) for 14 days. RESULTS: As a result the serum fasting blood glucose (FBG), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) levels were decreased following EACR administration. Immunohistochemical analysis revealed that the pancreatic tissue expression levels of TLR4 and NF-κB were downregulated after EACR administration. EACR suppressed pancreatic mRNA expression level of TLR4 and blocked the downstream NF-κB pathway in the pancreas. According to Western blot analysis EACR suppressed pancreatic TLR4 and NF-κB protein expression levels. Histopathological examination of the pancreas showed that STZ-induced pancreas lesions were alleviated by the EACR treatment. CONCLUSION: These findings suggest that the modulation of the IL-6 and TNF-α inflammatory cytokines and the suppression of the TLR4-NF-κB pathway are most likely involved in the anti-hyperglycemic effect of EACR in STZ-induced diabetic mice.

Structural characterization of a rhamnogalacturonan I-arabinan-type I arabinogalactan macromolecule from starfruit (Averrhoa carambola L.).

A structural characterization of polysaccharides obtained from edible tropical fruit named starfruit (Averrhoa carambola L.) was carried out. After fractionation by freeze-thaw and Fehling precipitation, a pectic polysaccharide was obtained. It was composed of rhamnose, arabinose, galactose and uronic acid in the 5.0:72.5:12.1:10.4 molar ratios, respectively. A combination of monosaccharide, GPC, methylation and NMR analysis and enzymatic hydrolysis with endo-ß-(1→4)-D-galactanase showed the presence of a rhamnogalacturonan I to which a branched arabinan and a type I arabinogalactan are attached. The arabinan moiety was formed by (1→5)-linked α-L-Araf units in the backbone, branched only at O-3 by (1→2)- and (1→3)-linked α-L-Araf units, while the type I arabinogalactan was formed by (1→4)- and (1→4,6)-linked ß-D-Galp units in the backbone with (1→5)-, (1→3,5)- and (1→3)-linked α-L-Araf units as side chains.