Parasitic Chytrids Upgrade and Convey Primary Produced Carbon During Inedible Algae Proliferation.

Microbial parasites have only recently been included in planktonic food web studies, but their functional role in conveying dietary energy still remains to be elucidated. Parasitic fungi (chytrids) infecting phytoplankton may constitute an alternative trophic link and promote organic matter transfer through the production of dissemination zoospores. Particularly, during proliferation of inedible or toxic algal species, such as large Cyanobacteria fostered by global warming, parasites can constitute an alternative trophic link providing essential dietary nutrients that support somatic growth and reproduction of consumers. Using phytoplankton-parasites associations grown under laboratory controlled conditions we assessed the fatty acids and biochemical composition of species with different nutritional quality and followed the metabolic pathway from the algal host and their parasites zoospores using compound-specific stable isotope analysis. This study demonstrated that chytrids are trophic upgraders able to retain essential nutrients that can be transferred to upper trophic levels both in terms of organic matter quantity and nutritional quality. Through the production of zoospores, nutritionally important long-chain polyunsaturated fatty acids that can be consequently assimilated by consumers. We conclude that parasitism at the base of aquatic food webs may represent a crucial trophic link for dietary nutrients and essential biomolecules alternative to herbivory or bacterivory, which can be particularly crucial during the proliferation of inedible or nutritionally inadequate algal species fostered by climate change.

Metabolic Activity of Anthocyanin Extracts Loaded into Non-ionic Niosomes in Diet-Induced Obese Mice.

PURPOSE: Anthocyanins (ACNs) are polyphenols that might reduce pathological processes associated with type 2 diabetes mellitus and other chronic diseases, but their bioavailability is still controversial. In this study, the metabolic activity of oral delivery of ACN-loaded niosomes was investigated and evaluated in a diet-induced obesity (DIO) mice model. METHODS: ACNs extracted from Vaccinium Meridionale by the supercritical fluid extraction method were loaded in niosomes. The niosomal formulation was physically characterized and further administrated in drinking water to obese, insulin resistant mouse. We evaluated the effect of ACN loaded niosomes on hyperglycemia, glucose and insulin intolerance and insulin blood levels in C57BL/6 J mice fed with a high-fat diet. RESULTS: The ACN-loaded particles were moderately monodisperse, showed a negative surface charge and 57% encapsulation efficiency. The ACN-loaded niosomes ameliorated the insulin resistance and glucose intolerance in the DIO mice model. Additionally, they reduced animal weight and plasma insulin, glucose, leptin and total cholesterol levels in obese mice. CONCLUSION: ACN-loaded niosomes administration, as a functional drink, had a beneficial effect on the reversal of metabolic abnormalities associated with obesity.

Preventive Effect and Mechanism of Ethyl Acetate Extract of Sceptridium ternatum in Monocrotaline-Induced Pulmonary Arterial Hypertension.

OBJECTIVE: To observe the effect and molecular mechanism of ethyl acetate extract of Sceptridium ternatum (STE) on the monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). METHODS: The main chemical components of Sceptridium ternatum were determined, and the effects in PAH rats were observed. A total of 140 Sprague Dawley rats were randomly and equally divided into the normal group, the model group, the Bosentan group, and the STE groups (2.5, 5, 10 g/kg) by the random number table method. The characteristic indicators of PAH were measured, and immunohistochemistry was used to observe the lung tissue of rats. Morphological changes of the lung tissue were observed under the light microscope. RESULTS: Compared with the normal group, rats in the model group showed a significant increase in right ventricular free wall thickness (RVFWT), mean pulmonary arterial pressure (mPAP), mean right ventricular pressure (mRVP), max right ventricular pressure (max RVP), weight of right ventricle (RV), and lung index (LI), while a significant decrease in pulmonary artery acceleration time (PAAT, P<0.01). Compared with the model group, rats treated with STE had a significant decrease of RVFWT, mPAP, mRVP, max RVP, and RV, while a significant increase of PAAT (P<0.01). After injection of MCT, nuclear factor- κB (NF- κB) p65 and α -smooth muscle actin (α -SMA) expression levels were up-regulated, and on the contrary, the treatment groups showed a significant down-regulation without dose-dependent trend. CONCLUSIONS: STE can relieve the PAH in rats. STE may relieve pulmonary vascular disease and pulmonary injury by down-regulating the expression of NF- κB p65 and α -SMA.

Flavonoids induce cell death in Leishmania amazonensis: in vitro characterization by flow cytometry and Raman spectroscopy.

Leishmaniasis comprises a group of infectious diseases with worldwide distribution, of which both the visceral and cutaneous forms are caused by Leishmania parasites. In the absence of vaccines, efficacious chemotherapy remains the basis for leishmaniasis control. The available drugs are expensive and associated with several secondary adverse effects. Due to these limitations, the development of new antileishmanial compounds is imperative, and plants offer various perspectives in this regard. The present study evaluated the in vitro leishmanicidal activity of flavonoids isolated from Solanum paludosum Moric. and investigated the mechanisms of cell death induced by them. These compounds were evaluated in vitro for their antileishmanial activity against Leishmania amazonensis promastigotes and they showed prominent leishmanicidal activity. The EtOAc fraction, gossypetin 3,7,8,4'-tetra-O-methyl ether (1), and kaempferol 3,7-di-O-methyl ether (3) were selected to be used in an in vitro assay against L. amazonensis amastigotes and cell death assays. The flavonoids (1) and (3) presented significant activity against L. amazonensis amastigotes, exhibiting the IC50 values of 23.3 ± 4.5 µM, 34.0 ± 9.6 µM, and 10.5 ± 2.5 µM for the EtOAc fraction, (1), and (3), respectively, without toxic effects to the host cells. Moreover, (1) and (3) induced blocked cell cycle progression at the G1/S transition, ultimately leading to G1/G0 arrest. Flavonoid (3) also induced autophagy. Using Raman spectroscopy in conjunction with principal component analysis, the biochemical changes in the cellular components induced by flavonoids (1) and (3) were presented. The obtained results indicated that the mechanisms of action of (1) and (3) occurred through different routes. The results support that the flavonoids derived from S. paludosum can become lead molecules for the design of antileishmanial prototypes.

Effects of salts and sucrose on the rheological behavior, thermal stability, and molecular structure of the Pereskia aculeata Miller mucilage.

The rheological behavior, thermogravimetric analysis (TGA), and atomic force microscopy (AFM) of the Pereskia aculeata Miller (OPN) mucilage treated with sodium chloride (NaCl), calcium chloride (CaCl2), and sucrose were evaluated. The experimental design was divided in a fractional factorial 25-1 for the screening of factors (OPN, sucrose, NaCl, CaCl2, and pH) and then in a 5 × 3 × 3 full factorial (OPN, sucrose, and NaCl). The model solutions used for the screening of factors presented shear-thinning behavior and the OPN mucilage concentrations were the factors that had significant effect on the apparent viscosity. Sucrose addition increased the thermal stability of the OPN mucilage solutions. OPN mucilage, sucrose, and NaCl were the variables with significant effect on thermogravimetric responses. The samples presented Newtonian behavior in 0-1.25% OPN mucilage concentrations and non-Newtonian behavior adjusted by power-law in 2.50-5.00% OPN mucilage concentrations with predominance of elastic behavior, contributing to the formation of stronger gels. The presence of sucrose in the systems containing OPN mucilage changed their rheological properties and salt additions caused reduction in viscosity. The AFM results provided a better understanding of the mechanism of OPN mucilage interactions in different solutions that justify the changes in viscosities.

Cytotoxic constituents from Penicillium concentricum, an endophytic fungus from Trichocolea tomentella.

In our continuing effort to identify bioactive secondary metabolites from natural sources, the antiproliferative activity of 23 compounds, previously isolated from Penicillium concentricum, was assessed using the sulforhodamine B assay. The cytotoxic effect was determined against HeLa cervical, HT-29 colon, MDA-MB-321 breast, PC-3, and DU-145 prostate cancer cell lines. Compounds were also tested in the mitochondrial transmembrane potential (MTP) and nuclear factor kappa B (NF-κB) target-based assays. The results showed that 2-bromogentisyl alcohol (2) and 3-hydroxy-benzenemethanol (8) exhibited the highest cytotoxic activity against different cancer cell lines. Epoxydon (14) showed selectivity against DU-145 prostate cancer cells [inhibitory concentration 50 (IC50)=1.2 µmol/l]. Compounds 2, 8, 14, 18, 21 also induced damage of MTP (IC50=0.1, 0.2, 7.0, 9.6, and 1.8 µmol/l, respectively). In the NF-κB assay, only compound 8 exhibited potent inhibition (IC50=0.3 µmol/l). Compounds 2 and 14 showed cytotoxic activity and induction of damage in mitochondrial membrane potential while compound 8 inhibited NF-κB and MTP damage. Additionally, compound 14 with selectivity against DU-145 prostate cancer cells induced cell cycle arrested in G2/M phase. Thus, compounds 2, 8, and 14 could be useful leads in the development of new anticancer agents from natural sources.

Nectandra grandiflora By-Products Obtained by Alternative Extraction Methods as a Source of Phytochemicals with Antioxidant and Antifungal Properties.

Nectandra grandiflora Nees (Lauraceae) is a Brazilian native tree recognized by its durable wood and the antioxidant compounds of its leaves. Taking into account that the forest industry offers the opportunity to recover active compounds from its residues and by-products, this study identifies and underlines the potential of natural products from Nectandra grandiflora that can add value to the forest exploitation. This study shows the effect of three different extraction methods: conventional (CE), ultrasound-assisted (UAE) and microwave-assisted (MAE) on Nectandra grandiflora leaf extracts (NGLE) chemical yields, phenolic and flavonoid composition, physical characteristics as well as antioxidant and antifungal properties. Results indicate that CE achieves the highest extraction phytochemical yield (22.16%), but with similar chemical composition to that obtained by UAE and MAE. Moreover, CE also provided a superior thermal stability of NGLE. The phenolic composition of NGLE was confirmed firstly, by colorimetric assays and infrared spectra and then by chromatographic analysis, in which quercetin-3-O-rhamnoside was detected as the major compound (57.75-65.14%). Furthermore, the antioxidant capacity of the NGLE was not altered by the extraction methods, finding a high radical inhibition in all NGLE (>80% at 2 mg/mL). Regarding the antifungal activity, there was observed that NGLE possess effective bioactive compounds, which inhibit the Aspergillus niger growth.

[Determination and principal component analysis of mineral elements based on ICP-OES in Nitraria roborowskii fruits from different regions].

The content of elements in fifteen different regions of Nitraria roborowskii samples were determined by inductively coupled plasma-atomic emission spectrometry(ICP-OES), and its elemental characteristics were analyzed by principal component analysis. The results indicated that 18 mineral elements were detected in N. roborowskii of which V cannot be detected. In addition, contents of Na, K and Ca showed high concentration. Ti showed maximum content variance, while K is minimum. Four principal components were gained from the original data. The cumulative variance contribution rate is 81.542% and the variance contribution of the first principal component was 44.997%, indicating that Cr, Fe, P and Ca were the characteristic elements of N. roborowskii.Thus, the established method was simple, precise and can be used for determination of mineral elements in N.roborowskii Kom. fruits. The elemental distribution characteristics among N.roborowskii fruits are related to geographical origins which were clearly revealed by PCA. All the results will provide good basis for comprehensive utilization of N.roborowskii.

Biological evaluation of a halogenated triterpenoid, 2α-bromo-dihydrobelulonic acid as inhibitor of human topoisomerase IIα and HeLa cell proliferation.

BACKGROUND: The pentacyclic lupane-type (6-6-6-6-5 type) triterpenoid, Betulinic acid (BA) is a potent inhibitor of topoisomerases and is of immense interest as anticancer drugs. However, the compound being highly lipophilic, has limited in vivo uptake capacity. BA derivatives with halogen substituent at C-2 have improved membrane permeability and cytotoxicity against cancer cells. AIM: The halogenated triterpenoid, 2α-bromo-dihydrobetulonic acid (B1) was synthesized from betulinic acid (BA) isolated from Bischofia javanica. Aim of the study was to determine whether B1 could act as a more efficient inhibitor of Topo IIα activity and HeLa cell proliferation, in comparison to BA. RESULT: B1 displayed efficient inhibition of DNA relaxation activity of topoisomerase IIα and the inhibitory effect was markedly improved upon pre-incubation of the compound with enzyme. Topoisomerase IIα inhibition by B1 was relieved in presence of increasing concentrations of DNA suggesting the compound as a reversible catalytic inhibitor. Subsequent UV and fluorescence spectroscopy studies indicated that B1 interacts and intercalates with DNA at concentrations signicantly greater than that required for topoisomerase IIα inhibition. The compound showed cytotoxic activity against HeLa cells with significantly lower IC50 value (7.5 µM) as compared to that of BA (30 µM) and had very low damaging/cytotoxic effect on normal cells. Treatment of B1 impaired HeLa cell proliferation by inducing Go-G1 arrest through lowered expression of cyclin D1 and PCNA polypeptides, and enhanced expression of p21. B1 treatment also increased the accumulation of early and late apoptotic cells in a concentration dependent manner as indicated by annexin V-FITC/PI binding assay.

Cyclombandakamines A1 and A2, Oxygen-Bridged Naphthylisoquinoline Dimers from a Congolese Ancistrocladus Liana.

Cyclombandakamines A1 (1) and A2 (2), both with an unprecedented pyrane-cyclohexenone-dihydrofuran sequence and six stereocenters and two chiral axes, are the first oxygen-bridged dimeric naphthylisoquinoline alkaloids. They were isolated from the leaves of an as yet unidentified Congolese Ancistrocladus species. Their stereostructures were established by spectroscopic, chemical, and chiroptical methods in combination with DFT and TDDFT calculations. They apparently originate from a cascade of oxidative cyclization reactions of "open-chain" naphthylisoquinoline dimers and exhibit significant antiprotozoal activities.

Control of cytokinin and auxin homeostasis in cyanobacteria and algae.

BACKGROUND AND AIMS: The metabolism of cytokinins (CKs) and auxins in vascular plants is relatively well understood, but data concerning their metabolic pathways in non-vascular plants are still rather rare. With the aim of filling this gap, 20 representatives of taxonomically major lineages of cyanobacteria and algae from Cyanophyceae, Xanthophyceae, Eustigmatophyceae, Porphyridiophyceae, Chlorophyceae, Ulvophyceae, Trebouxiophyceae, Zygnematophyceae and Klebsormidiophyceae were analysed for endogenous profiles of CKs and auxins and some of them were used for studies of the metabolic fate of exogenously applied radiolabelled CK, [3H]trans-zeatin (transZ) and auxin ([3H]indole-3-acetic acid (IAA)), and the dynamics of endogenous CK and auxin pools during algal growth and cell division. METHODS: Quantification of phytohormone levels was performed by high-performance or ultrahigh-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-MS/MS, UHPLC-MS/MS). The dynamics of exogenously applied [3H]transZ and [3H]IAA in cell cultures were monitored by HPLC with on-line radioactivity detection. KEY RESULTS: The comprehensive screen of selected cyanobacteria and algae for endogenous CKs revealed a predominance of bioactive and phosphate CK forms while O- and N-glucosides evidently did not contribute greatly to the total CK pool. The abundance of cis-zeatin-type CKs and occurrence of CK 2-methylthio derivatives pointed to the tRNA pathway as a substantial source of CKs. The importance of the tRNA biosynthetic pathway was proved by the detection of tRNA-bound CKs during the course of Scenedesmus obliquus growth. Among auxins, free IAA and its oxidation catabolite 2-oxindole-3-acetic acid represented the prevailing endogenous forms. After treatment with [3H]IAA, IAA-aspartate and indole-3-acetyl-1-glucosyl ester were detected as major auxin metabolites. Moreover, different dynamics of endogenous CKs and auxin profiles during S. obliquus culture clearly demonstrated diverse roles of both phytohormones in algal growth and cell division. CONCLUSIONS: Our data suggest the existence and functioning of a complex network of metabolic pathways and activity control of CKs and auxins in cyanobacteria and algae that apparently differ from those in vascular plants.

Formation of lipid bodies and changes in fatty acid composition upon pre-akinete formation in Arctic and Antarctic Zygnema (Zygnematophyceae, Streptophyta) strains.

Filamentous green algae of the genus Zygnema (Zygnematophyceae, Streptophyta) are key components of polar hydro-terrestrial mats where they face various stressors including UV irradiation, freezing, desiccation and osmotic stress. Their vegetative cells can develop into pre-akinetes, i.e. reserve-rich, mature cells. We investigated lipid accumulation and fatty acid (FA) composition upon pre-akinete formation in an Arctic and an Antarctic Zygnema strain using transmission electron microscopy and gas chromatography coupled with mass spectrometry. Pre-akinetes formed after 9 weeks of cultivation in nitrogen-free medium, which was accompanied by massive accumulation of lipid bodies. The composition of FAs was similar in both strains, and α-linolenic acid (C18:3) dominated in young vegetative cells. Pre-akinete formation coincided with a significant change in FA composition. Oleic (C18:1) and linoleic (C18:2) acid increased the most (up to 17- and 8-fold, respectively). Small amounts of long-chain polyunsaturated FAs were also detected, e.g. arachidonic (C20:4) and eicosapentaenoic (C20:5) acid. Pre-akinetes exposed to desiccation at 86% relative humidity were able to recover maximum quantum yield of photosystem II, but desiccation had no major effect on FA composition. The results are discussed with regard to the capability of Zygnema spp. to thrive in extreme conditions.

Erythronium japonicum attenuates histopathological lung abnormalities in a mouse model of ovalbumin-induced asthma.

Asthma is a chronic lung condition that can induce mucus hypersecretion and pulmonary obstruction and may even cause death, particularly in children and older individuals. Erythronium japonicum (E. japonicum) is a traditional herb used in Korea and East Asian countries that has been found to exert free radical scavenging activity and anti-proliferative effects in human colorectal carcinoma cells. In the present study, we evaluated the anti-asthmatic effects of an extract of E. japonicum in a mouse model of ovalbumin (OVA)­induced asthma. Female BALB/c mice were sensitized with an intraperitoneal injection of OVA and aluminum hydroxide hydrate on days 1 and 8 and then received the following treatments on days 21 to 25: i) control (no treatment), ii) sterilized tap water (given orally), iii) 1 mg/kg/day dexamethasone (administered orally), iv) 60 mg/kg/day E. japonicum extract, and v) 600 mg/kg/day E. japonicum extract. On the same days, all the mice except those in the control group were challenged 1 h later with nebulized 5% OVA for 30 min. We found that treatment with E. japonicum extract suppressed the OVA-induced increase in the number of white blood cells and decreased the IgE level in the bronchoalveolar lavage fluid samples obtained from the mice. Histopathological analysis of the lung tissues revealed that E. japonicum attenuated the asthma-related morphological changes in the mouse lung tissue, including the increased secretion of mucus in the bronchioles, eosinophil infiltration around the bronchioles and vessels, and goblet cell and epithelial cell hyperplasia. Immunohistochemical analysis revealed that treatment with E. japonicum extract suppressed the OVA-induced proliferation of T helper cells (CD4+) and B cells (CD19+) in the mouse lung tissue. Furthermore, treatment with E. japonicum extract modulated the expression of both T helper 2 cell-related factors [GATA binding protein 3 (GATA-3), tumor necrosis factor-α (TNF­α), interleukin (IL)-4, IL-5, IL-6 and IL-13], as well as that of T helper 1 cell-related factors [(interferon-γ (IFN-γ), IL-12p35 and IL-12p40]. These findings suggest that E. japonicum may potentially be used as an anti-asthmatic treatment.

Fermented Acanthopanax koreanum Root Extract Reduces UVB- and H2O2-Induced Senescence in Human Skin Fibroblast Cells.

The present study assessed the effects of an aqueous extract of Acanthopanax koreanum root (AE) and of AE following fermentation by lactic acid bacteria (Lactobacillus plantarum and Bifidobacterium bifidum) (AEF) on human skin fibroblast HS68 cells exposed to ultraviolet B (UVB) irradiation and oxidative stress. AEF effectively antagonized the senescence-associated ß-galactosidase staining and upregulation of p53 and p21(Cip1/WAF1) induced by UVB or H2O2 treatment in HS68 cells. It also exhibited excellent antioxidant activities in radical scavenging assays and reduced the intracellular level of reactive oxygen species induced by UVB or H2O2 treatment. The antioxidant and antisenescent activities of AEF were greater than those of nonfermented A. koreanum extract. AEF significantly repressed the UVB- or H2O2-induced activities of matrix metalloproteinase (MMP)-1 and -3, overexpression of MMP-1, and nuclear factor κB (NF-κB) activation. This repression of NF-κB activation and MMP-1 overexpression was attenuated by a mitogen-activated protein kinase activator, suggesting that this AEF activity was dependent on this signaling pathway. Taken together, these data indicated that AEF-mediated antioxidant and anti-photoaging activities may produce anti-wrinkle effects on human skin.

The regulatory mechanism of ion permeation through a channelrhodopsin derived from Mesostigma viride (MvChR1).

The five glutamate (E) residues of transmembrane (TM)-2 of channelrhodopsin (CrChR)-2 are conserved among several members of the ChR family. A point mutation of one of them, E97, to a nonpolar alanine (E97A) reduced the photocurrent amplitude without influencing other photocurrent properties. The charge at this position is also the determinant of the Gd(3+)-dependent block of the channel. It has thus been suggested that E97 interacts with hydrated cations to facilitate their permeation and that these residues are the primary binding sites of Gd(3+). However, the counterpart of this position is alanine for MvChR1 from Mesostigma viride. Here we investigated the ion permeation and the Gd(3+)-dependent channel block of MvChR1. We found that the high-affinity binding site of Gd(3+) was absent in MvChR1, but was dependent on the negativity at this position. However, the ion permeation through the channel was markedly interfered with a negative charge at this position. Based on these findings, it is proposed that the ions can pass through the pore with minimal interaction with this position.

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)-ß-D-glucuropyranosyl-23-aldehyde-30-norolean-12, 20 (29)-dien-28-oic acid-28-O-ß-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.

Further Study on Chemical Constituents of Parnassia wightiana Wall: Four New Dihydro-ß-agarofuran Sesquiterpene Polyesters.

Four new (1-4), along with six known (5-10) dihydro-ß-agarofuran sesquiterpene polyesters were isolated from the whole plants of Parnassia wightiana. The new compounds were structurally elucidated through spectroscopic analysis including UV (Ultraviolet Spectrum), IR (Infrared Spectrum), ¹H-NMR (¹Hydrogen-Nuclear Magnetic Resonance), ¹³C-NMR (¹³Carbon-Nuclear Magnetic Resonance), DEPT (Distortionless Enhancement by Polarization Transfer), ¹H-¹H COSY (¹H-¹H Correlation Spectroscopy), HSQC (Heteronuclear Single Quantum Coherence), HMBC (Heteronuclear Multiple Bond Correlation), NOESY (Nuclear Overhauser Enhancement Spectroscopy) and HR-MS (High Resolution Mass Specttrum) and their absolute configurations were proposed by comparison of NOESY spectra and specific optical rotations with those of known compounds and biosynthesis grounds. Compound 2 is the first sesquiterpene alkaloid isolated from this plant. New compounds 1-4 exhibited some cytotoxic activities against NB4, MKN-45 and MCF-7 cells at 20 µM and of which 4 showed the highest activity against NB4 and MKN-45 cells with inhibition rates of 85.6% and 30.5%, respectively.

Cellular Anti-Melanogenic Effects of a Euryale ferox Seed Extract Ethyl Acetate Fraction via the Lysosomal Degradation Machinery.

The aim of this study was to investigate the effect of ethyl acetate fraction of Euryale ferox seed extracts (Efse-EA) on melanogenesis in immortalized mouse melanocyte cell line, melan-a. Efse-EA showed strong dose-dependent mushroom tyrosinase inhibitory activity. Treatment of melan-a cells with 30 µg/mL Efse-EA produced strong inhibition of cellular tyrosinase and melanin synthesis. Efse-EA significantly reduced the levels of melanogenesis-related proteins, such as tyrosinase, tyrosinase-related proteins 1 and 2, and microphthalmia-associated transcription factor. Because Efse-EA treatment reduced tyrosinase protein levels without changing its mRNA expression, we investigated whether this decrease was related to proteasomal or lysosomal degradation of tyrosinase. We found that chloroquine, a lysosomal proteolysis inhibitor, almost completely abolished both the down-regulation of tyrosinase and the inhibition of melanin synthesis induced by Efse-EA. These results suggested that Efse-EA may contribute to the inhibition of melanogenesis by altering lysosomal degradation of tyrosinase, and that this extract may provide a new cosmetic skin-whitening agent.

Antibacterial oleanane-type triterpenoids from pericarps of Akebia trifoliata.

Three new oleanane triterpenoids, 2α,3ß,29-trihydroxyolean-12-en-28-oic acid (1), 2α,3ß-dihydroxy-23-oxo-olean-12-en-28-oic acid (2) and 2α,3ß,21ß,22α-tetrahydroxyolean-12-en-28,29-dioic acid (3), and ten known ones, maslinic acid (4), arjunolic acid (5), oleanolic acid (6), 3-epi-oleanolic acid (7), stachlic acid A (8), serratagenic acid (9), gypsogenic acid (10), 2α,3ß-dihydroxyol-ean-13(18)-en-28-oic acid (11), mesembryanthemoidigenic acid (12) and 12α-hydroxy-δ-lactone (13), were isolated from the pericarps of Akebia trifoliata, a new valued fruit crop in China. Their structures were elucidated on the basis of extensive spectroscopic analysis. Compounds 8, 10, 11 and 13 were isolated for the first time from the genus Akebia. All the compounds were tested for their antimicrobial activity against five bacterial strains. Compounds 4, 6 and 11 showed significant antibacterial activity toward all the assayed microorganisms with MIC values ranging from 0.9 to 15.6µg/mL, which were close or even more potent than the reference compound Kanamycin (MIC values ranging from 1.9 to 3.9µg/mL).

Pharmacology and phytochemistry of the Nitraria genus (Review).

Plants from the Nitraria genus, members of the Zygophyllaceae family, grow naturally in Europe, Africa, Australia and the central Asian desert. Previous pharmacological research has provided evidence that members of the Nitraria genus have numerous beneficial effects. In the present review, the pharmacological and phytochemical studies of Nitraria were presented and assessed. The review was written using information published between 1968 and 2013 from a number of reliable sources, including ScienceDirect, Springer, PubMed, EMBASE and CNKI. Numerous compounds, such as alkaloids and flavonoids have been isolated from the plants of this genus in the past, and multiple members of these constituents have been demonstrated to exert antitumor or anti-oxidative activities. The extracts of plants of the Nitraria genus possess antitumor, antiproliferative, anti-oxidative, antifatigue, anti-mutagenic, antimicrobial, hypotensive, hepatoprotective, lipid-lowering and hypoglycemic effects. However, the possible active components in the fraction and the molecular mechanisms require further investigation prior to their use in clinical practice.