Knowledge Mapping of Opuntia Milpa Alta Since 1998: A Scientometric Analysis

Opuntia Milpa Alta is a cactus cultivated, domesticated, hybridized and selected from the plant Opuntia ficus-indica by Mexican agricultural experts, which can be used as fruit and vegetable. Opuntia Milpa Alta leaves and fruit are superior to wild varieties and suitable for storage and transportation. In 1998, Opuntia Milpa Alta was introduced to China from Mexico by the Quality Product Development Center of the Ministry of Agriculture of China. Up to now, the Opuntia Milpa Alta has been cultivated on a certain scale in China. This study aims to identify the research progress and development trends of Opuntia Milpa Alta in China. Papers published between 1998 to 2019 from two major Chinese academic databases (CNKI and Wangfang) with a topic search related to Opuntia Milpa Alta were collected. The research progress and development trends were analyzed based on CiteSpace software of text mining and visualization. The analysis found that Opuntia Milpa Alta has gone through three obvious research phases after being introduced to China. In the first phase, the researchers paid attention to its cultivation method. Subsequently, researchers began to use extraction methods to extract some of its components, such as polysaccharides and flavonoids. Finally, these extracted ingredients began to be used in some biomedical research.     

Antioxidant,Anti-Skin-Aging,Anti-Inflammatory,and Anti-Acetylcholinesterase Activities of Rourea oligophlebia Extracts

The objective of this study was to evaluate the antioxidant, anti-skin-aging, anti-inflammatory, and anti-acetylcholinesterase activities of the hexane (n-hex), AcOEt, BuOH, MeOH, and aqueous extracts from R. oligophlebia roots. The total phenolic and flavonoid contents (TPC and TFC) were determined using Folin-Ciocalteu and AlCl₃ colorimetric assays. The antioxidant capacity was examined by reducing power (RP), ferric reducing antioxidant power (FRAP), ABTS⋅⁺, and DPPH⋅⁺ radical cation assays. All extracts potentially exhibited antioxidant activity with IC₅₀ values ranging from 2.93 to 5.73 μg/mL for ABTS⋅⁺ and from 5.69 to 7.65 μg/mL for DPPH⋅⁺ except the n-hex extract. The BuOH, MeOH, and aqueous extract possess promising anti-skin-aging activities, as observed by an attenuation of UV-A toxicity on human keratinocytes. We proposed that these anti-skin-aging properties are possibly due to direct scavenging activity against reactive oxygen species and upregulate cellular antioxidant machinery. Moreover, we found that the antioxidant capacity was well correlated with anti-inflammatory capacity against nitric oxide (NO) production in terms of the n-hex, AcOEt, and BuOH extracts with IC₅₀ values from 23.21 to 47.1 μg/mL. In contrast, these activities were found to be poorly correlated with AchE activity. To the best of our knowledge, this is the first report of the antioxidant, anti-skin-aging, anti-inflammatory, and anti-acetylcholinesterase activities of the extracts of R. oligophlebia roots. These findings indicated that this species could be a potential source of natural antioxidant, anti-aging, and anti-inflammatory agents. Consequently, it may be suggested as a medicinal plant that prevents diseases related to oxidative stress and inflammatory responses.     

Hypoglycemic effect of polysaccharides produced by submerged mycelial culture of Laetiporus sulphureus on streptozotocininduced diabetic rats

The hypoglycemic effect of the crude extracellular polysaccharides (EPS) produced from submerged mycelial culture of an edible mushroom Laetiporus sulphureus var. miniatus in streptozotocin (STZ)-induced diabetic rat was investigated. Hypoglycemic effect of EPS was evaluated in STZ-induced diabetic rats, and its possible mechanism was suggested by the results of western blot analysis and immunohistochemical staining. The results revealed that orally administrated EPS, when given 48 h after STZ treatment exhibited an excellent hypoglycemic effect, lowering the average plasma glucose level in EPS-fed rats to 43.5% of STZ-treated rats. The plasma levels of total cholesterol and triglyceride were significantly increased upon STZ treatment and they were markedly reduced by oral administration of EPS to near-normal levels. The results of immunohistochemical staining of the pancreatic tissues showed that EPS treatment considerably increased the insulin antigenesity of diabetic islet β-cells, suggesting the possibility of β-cell proliferation or regeneration by EPS therapy. Moreover, immunoblotting study revealed that protein levels of iNOS was increased and SOD2, catalase, GPx were significantly increased after EPS treatments, suggesting alleviated oxidative stress mediated by STZ. Orally administrated EPS exhibited considerable hypoglycemic effect in STZ-induced diabetic rats and that these EPS may be useful for the management of diabetes mellitus.     

Characterization of Polar and Non‐Polar Compounds of House Edible Bird's Nest (EBN) from Johor,Malaysia

This work investigated the polar (PC: protein, amino acid and metabolite) and non‐polar (NPC: fatty acid) compounds and bioactivity characteristics of the EBN harvested from the state of Johor in Malaysia. The electrophoretic gels exhibited 15 protein bands (16–173 kD) with unique protein profile. Amino acids analysis by AccQ?Tag method revealed 18 types of amino acids in EBN. Metabolite profiling was performed using High‐Performance Liquid Chromatography coupled with Quadrupole Time‐of‐Flight Mass Spectrometer (HPLC‐QTOF/MS) technique and a total of 54 compounds belonging to different groups were detected and identified. These findings help to uncover the relation of therapeutic activity of EBN. The EBN was further extracted with AcOEt and BuOH. The AcOEt extract was fractionated into three fractions (F₁?F₃), and the high triglyceride content in F₂ was verified by gC‐FID. The three groups of fatty acids discovered in EBN are 48.43 % of poly‐unsaturated (PUFA), 25.35 % of saturated fatty acids (SFA) and 24.74 % of mono‐unsaturated fat (MUFA). This is the first time to report results ofEBN, BuOH, and AcOEt extracts and of fraction F₂ (TEBN) on their analysis for their antioxidant activities by DPPH, ABTS and catalase assay and for their paraoxonase and anti‐tyrosinase activities. The results showed that TEBN exhibited the significant bioactivity in all assays. These findings suggest that TEBN is a good source for natural bioactive compounds in promoting body vigor. Current work widened the content of EBN especially on the triglyceride and also marked the content of specific location (Johor, Malaysia) of EBN origin.     

Biochemical effects of Citrullus colocynthis in normal and diabetic rats

Diabetes mellitus is one of the most common endocrine diseases. In UAE many traditional plants such as the Citrullus colocynthis (Handal) are used as antidiabetic remedies. The aim of this study was to examine the effect of the aqueous extract of the seed of C. colocynthis on the biochemical parameters of normal and streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by a single intraperitoneal (60 mg/kg body wt¹) injection of STZ. Normal and diabetic rats were fed with the plant extract daily by oral intubation for 2 weeks. Blood sample were collected at the beginning and end of the experiment for the measurement of biochemical parameters. The plasma level of alanine aminotranferase (ALT), alkaline phosphatase (ALP), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), lactic dehydrogenase (LDH) increased significantly after the onset of diabetes. Oral administration of the plant extract reduced the plasma level of AST and LDH significantly. However, the plant extract failed to reduce the increased blood level of GGT and ALP in diabetic rats. Blood urea nitrogen (BUN) increased significantly after the onset of diabetes. No significant difference was observed in the blood creatinine, K⁺, Na⁺, Ca²⁺ and P levels of normal and diabetic rats. The plant extract did not have any effect on BUN level, however, it caused an increase in the level of K⁺, Na⁺ in diabetic rats. In conclusion, oral administration of the aqueous extract of the C. colocynthis can ameliorate some of the toxic effects of streptozotocin. (Mol Cell Biochem 261: 143–149, 2004)     

Inhibition of endogenous glucose production accounts for hypoglycemic effect of Spergularia purpurea in streptozotocin mice.

The purpose of this study was to determine the underlying mechanism of the hypoglycemic activity of the aqueous extract perfusion of Spergularia purpurea (SP) in diabetic mice and streptozotocin-induced diabetic rats. The aqueous extract was administered intravenously and the blood glucose levels were determined within 4 hours after starting the treatment. Plasma insulin concentrations and endogenous glucose production were also determined. The aqueous extract at a dose of 10 mg/kg produced a significant decrease in blood glucose levels in normal rats (P < 0.05), and even more in diabetic rats (P < 0.001). This hypoglycemic effect might be due to an extra-pancreatic action of the aqueous extract of SP, since the basal plasma insulin concentrations were unchanged after SP treatment. In diabetic mice, a similar effect was observed and the results showed that aqueous extract of SP caused a potent inhibitor effect on basal endogenous glucose production (p < 0.001). We conclude that aqueous extract perfusion of SP inhibits endogenous glucose production in mice. This inhibition is at least one mechanism explaining the observed hypoglycemic activity of this plant in diabetic animals.     

Hypoglycemic effect of Sclerocarya birrea {(A. Rich.) Hochst.} [Anacardiaceae] stem-bark aqueous extract in rats

This study was undertaken to evaluate the hypoglycemic effect of Sclerocarya birrea [(A. Rich.) Hochst.] subspecies caffra (Sond.) Kokwaro [family: Anacardiaceae] stem-bark aqueous extract in normal (normoglycemic) and in streptozotocin (STZ)-treated, diabetic Wistar rats. In one set of experiments, graded doses of S. birrea stem-bark aqueous extract (SB, 100-800 mg/kg p.o.) were separately administered to groups of fasted normal and fasted diabetic rats. In another set of experiments, a single dose of the plant aqueous extract (SB, 800 mg/kg p.o.) was used. The hypoglycemic effect of this single dose (SB, 800 mg/kg p.o.) of S. birrea stem-bark aqueous extract was compared with that of chlorpropamide (250 mg/kg p.o.) in both fasted normal and fasted diabetic rats. Following acute treatment, relatively moderate to high doses of S. birrea stem-bark extract (SB, 100-800 mg/kg p.o.) produced dose-dependent, significant reductions (P < 0.05-0.001) in the blood glucose concentrations of both fasted normal and fasted diabetic rats. Chlorpropamide (250 mg/kg p.o.) also produced significant reductions (P < 0.05-0.001) in the blood glucose concentrations of the fasted normal and fasted diabetic rats. Administrations of the single dose of S. birrea stem-bark aqueous extract (SB, 800 mg/kg p.o.) significantly reduced (P 0.01 < 0.001) the blood glucose levels of both fasted normal (normoglycemic) and fasted STZ-treated, diabetic rats. The results of this experimental animal study indicate that aqueous extract of Sclerocarya birrea possesses hypoglycemic activity, and thus lend credence to the suggested folkloric use of the plant in the management and/or control of adult-onset, type-2 diabetes mellitus in some African communities.     

Characterization of Secondary Metabolites in Flowers of Sanguisorba officinalis L. by HPLC‐DAD‐MSn and GC/MS

The investigations reported here focus on an in‐depth characterization of the secondary metabolite profile of Sanguisorba officinalis flowers. For this purpose, fresh flowers were extracted with MeOH/H₂O and EtOH/H₂O and the resulting crude extracts fractionated using CH₂Cl₂, AcOEt, and BuOH. Individual compounds were characterized by high performance liquid chromatography and gas chromatography coupled with mass spectrometric detection (HPLC‐DAD‐MSⁿ and GC/MS). MeOH/H₂O extraction and LC/MSⁿ investigations revealed the occurrence of flavonoid glycosides (quercetin, kaempferol), ellagitannin glycosides and four anthocyanins. Among the latter, two components, i. e., cyanidin‐malonyl‐glucose and cyanidin‐galloyl‐hexose, have not been reported for S. officinalis so far. Furthermore, phenylethylamine was characterized for the first time in Sanguisorba by pH value dependent extraction with CH₂Cl₂. In addition, AcOEt and BuOH extracts were analyzed by GC/MS both prior to and after acid hydrolysis of secondary metabolites. For this purpose, the extracts were treated with 1 n HCl solution (105 °C, 1 h) and derivatized with BSTFA. Analyses revealed the occurrence of several classes of phenolic compounds, such as gallic acid, hydroxybenzoic acid, hydroxycinnamic acid and ellagic acid derivatives. Additionally, the most prominent ursane‐type triterpenoid (ziyu‐glycoside I) from Sanguisorba and its corresponding aglycone isomers were detected and assigned based on their characteristic fragmentation patterns.     

Management of Citrus sinensis peels for protection and treatment against gastric ulcer induced by ethanol in rats

Abstract

Introduction: Stomach ulcer is one of the most prevalent disorders worldwide. The study was aimed to isolate and characterize the major polymethoxylated flavonoids in Citrus sinensis peels petroleum ether extract and investigate its protective and curative effect on gastric ulcer.

Material and methods: Some spectral analyses were used for identification of the isolated compounds from the petroleum ether extract of Citrus sinensis peels. One oral dose (0.5?ml/100?g b.wt.) of absolute ethanol was orally given to rats after starvation for 24?h to induce gastric ulcer. To explore the protective and curative role of the plant extract, it was orally (250?mg/kg b.wt.) given for 1 week either before or post-ulcer induction. A reference drug, ranitidine (100?mg/kg b.wt.), was also evaluated. Stomach acidity, gastric volume, lesion counts, glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), acid phosphatase (AP), interlukin-10 (IL-10) and prostaglandin E2 (PGE2) were estimated. Stomach histopathological features were monitored.

Results: Nine polymethoxy flavonoids were identified from the extract. Treatment with C. sinensis peels extract recorded amelioration in all parameters.

Conclusion: Citrus sinensis petroleum ether peels extract had protective and curative effects against gastric ulcer. Therefore, the extract recorded anti-secretory, anti-ulcerative, anti-inflammatory, and antioxidant effects. Its healing action exceeded its protective role due to its richness in polymethoxylated flavonoids     

Chemical Constituents from the Stems of Daphne holosericea (Diels) Hamaya

Two new compounds, one flavanol dimer dapholosericol A ( 1 ) and one tigliane diterpene dapholosericin A ( 2 ), together with ten known ones, were isolated from the AcOEt extract of Daphne holosericea (Diels ) Hamaya . Their structures were elucidated by their spectroscopic data analysis. Compounds 1 and 2 showed moderate activities against acetylcholinesterase with inhibition ratio of 36% and 29% at a concentration of 100 μmol/l, respectively.     

Hypoglycemic activity of leaf organic extracts from Smallanthus sonchifolius: Constituents of the most active fractions

The aim of the present study was to determine the in vivo hypoglycemic activity of five organic extracts and enhydrin obtained from yacon leaves. The main constituents of the most active fraction were identified. Five organic extracts and pure crystalline enhydrin were administered to normoglycemic, transiently hyperglycemic and streptozotocin (STZ)-diabetic rats. The fasting and post-prandial blood glucose, and serum insulin levels were estimated and an oral glucose tolerance test (OGTT) was performed for the evaluation of hypoglycemic activity and dose optimization of each extract.We found that the methanol, butanol and chloroform extracts showed effective hypoglycemic activity at minimum doses of 50, 10 and 20 mg/kg body weight, respectively, and were selected for further experiments. Oral administration of a single-dose of each extract produced a slight lowering effect in the fasting blood glucose level of normal healthy rats, whereas each extract tempered significantly the hyperglycemic peak after food ingestion. Daily administration of each extract for 8 weeks produced an effective glycemic control in diabetic animals with an increase in the plasma insulin level. Phytochemical analysis of the most active fraction, the butanol extract, showed that caffeic, chlorogenic and three dicaffeoilquinic acids were significant components. Additionally, enhydrin, the major sesquiterpene lactone of yacon leaves, was also effective to reduce post-prandial glucose and useful in the treatment of diabetic animals (minimum dose: 0.8 mg/kg body weight).The results presented here strongly support the notion that the phenolic compounds above as well as enhydrin are important hypoglycemic principles of yacon leaves that could ameliorate the diabetic state.     

In vitro toxicity and antidiabetic activity of a newly developed polyherbal formulation (MAC-ST/001) in streptozotocin-induced diabetic Wistar rats

The present study was designed to investigate the hypoglycemic effect of an aqueous extract of MAC-ST/001 (a new polyherbal formulation) which was given once daily to rats at different doses. The animals were divided into diabetic and nondiabetic control groups. The duration of each experiment lasted from 1 week to 1 month, and the results were compared with that of the standard hypoglycemic drug glibenclamide (10 mg/kg), which was given once daily. In this study, biochemical and histopathological parameters were studied in streptozotacin (STZ) (single intraperitoneal injection of 55 mg/kg)-induced diabetic rats. The diabetic rats showed a significant (p?<?0.05 and p?<?0.01) decrease in their body weight and serum amylase with marked elevation in blood glucose, serum cholesterol, blood urea nitrogen, creatinine, alkaline phosphatase, and serum transaminases (AST and ALT) after 1 week till the 28th day of diabetes. Cytotoxicity of MAC-ST/001 formulation was also studied on C2C12, 3T3-L1, and HepG2 cells through MTT assay. Histological examination of the liver and pancreas of normal control, diabetic control, and drug-treated rats revealed significant results. Finally, it was concluded that administration of this MAC-ST/001 extract reversed most blood and tissue changes caused by STZ-induced diabetes in rats.     

A Comparative Study on Hulled Adlay and Unhulled Adlay through Evaluation of Their LPS‐Induced Anti‐Inflammatory Effects,and Isolation of Pure Compounds

Coicis semen (=the hulled seed of Coix lacryma‐jobi L. var. ma‐yuen (Rom.Caill. ) Stapf ; Gramineae), commonly known as adlay and Job's tears, is widely used in traditional medicine and as a nutritious food. Bioassay‐guided fractionation of the AcOEt fraction of unhulled adlays, using measurement of nitric oxide (NO) production on lipopolysaccharide (LPS)‐stimulated RAW 264.7 macrophage cells, led to the isolation and identification of two new stereoisomers, (+)‐(7′S,8′R,7″S,8″R)‐guaiacylglycerol β‐O‐4′‐dihydrodisinapyl ether ( 1 ) and (+)‐(7′S,8′R,7″R,8″R)‐guaiacylglycerol β‐O‐4′‐dihydrodisinapyl ether ( 2 ), together with six known compounds, 3 – 8 . Compounds 3 and 4 exhibited inhibitory activities on LPS‐induced NO production with IC₅₀ values of 1.4 and 3.7 μM , respectively, and suppressed inducible nitric oxide synthase (iNOS) and cyclooxygenase‐2 (COX‐2) protein expressions in RAW 264.7 macrophage cells. Simple high‐performance liquid chromatography with ultraviolet detection (HPLC/UV) was used to compare the AcOEt fraction of unhulled adlays responsible for the anti‐inflammatory activity in RAW 264.7 cells and the inactive AcOEt fraction of hulled adlays.     

Combination of HPLC chromatogram and hypoglycemic effect identifies isoflavones as the principal active fraction of Belamcanda chinensis leaf extract in diabetes treatment

In previous study, we demonstrated the hypoglycemic effect of aqueous extract of Belamcanda chinensis leaves in rats. Here, we separated the aqueous extract of B. chinensis leaves and investigated the spectrum-effect relationships between HPLC chromatograms and hypoglycemic activities of different isolates from B. chinensis leaf extract. Sequential solvent extraction with petroleum ether, chloroform, acetic ester and n-butanol provided several isolates showing similar hypoglycemic activities, making it difficult to discriminate the active fractions. Stepwise elution through HP20 macroporous resin by water, 40% and 95% ethanol provided isolates with distinct hypoglycemic activities, representing a simple, rapid and efficient preparative separation method. Combination of HPLC chromatogram and pharmacological effect targeted a hypoglycemic activity-related region in HPLC chromatogram. Each peak in this region was analyzed by UV spectrum scan. Most of them were flavonoids in which tectoridin and swertisin were known flavonoids with anti-diabetic activities. In together, this work provides a general model of combination of HPLC chromatography and pharmacological effect to study the spectrum-effect relationships of aqueous extract from B. chinensis leaves, which can be used to find principle components of B. chinensis on pharmacological activity.     

In vitro evaluation of the efficacy of plant and callus extracts of Cardiospermum halicacabum L. on important phytopathogenic fungi

The aqueous and different solvent extracts viz., petroleum ether, chloroform, methanol and ethanol extracts of leaf and leaf derived callus of Cardiospermum halicacabum L. (Sapindaceae) at different concentrations were screened in vitro for antifungal activity by the poisoned food technique against a wide array of seed-borne phytopathogenic fungi. The test organisms include Aspergillus flavus, A. niger, Curvularia lunata, Drechslera halodes, Fusarium moniliforme, F. solani, and F. oxysporum, which are frequently associated with sorghum [Sorghum bicolor (L.) Moench], maize (Zea mays L.) and paddy (Oryza sativa L.) seeds. Aqueous leaf extracts of C. halicacabum showed significant inhibition was observed at 50% concentration particularly in Aspergillus species. With regard to the comparative efficiency of leaf and leaf derived callus extracts, aqueous leaf extract was found to be more effective than callus extract. Among the different solvent extracts, it was observed that at 3000 ppm concentration methanol extract of C. halicacabum leaf recorded the highest degree of activity and percentage inhibition was more, but in petroleum ether and chloroform extracts did not show any significant activity. C. halicacabum leaf derived callus at 3000 ppm methanol extract showed significant antifungal activity on Fusarium species. Leaf of C. halicacabum aqueous and methanol extract showed significant antifungal activity against all the tested fungi. C. halicacabum has significant medicinal value, hence the results of the present investigation indicate that it could be exploited in the management of seed-borne pathogenic fungi.     

Antiparkinsonian Effects of Aqueous Methanolic Extract of Hyoscyamus niger Seeds Result From its Monoamine Oxidase Inhibitory and Hydroxyl Radical Scavenging Potency

Hyoscyamus species is one of the four plants used in Ayurveda for the treatment of Parkinson’s disease (PD). Since Hyoscyamus niger was found to contain negligible levels of L-DOPA, we evaluated neuroprotective potential, if any, of characterized petroleum ether and aqueous methanol extracts of its seeds in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD in mice. Air dried authenticated H. niger seeds were sequentially extracted using petroleum ether and aqueous methanol and were characterized employing HPLC-electrochemistry and LCMS. Parkinsonian mice were treated daily twice with the extracts (125–500 mg/kg, p.o.) for two days and motor functions and striatal dopamine levels were assayed. Administration of the aqueous methanol extract (containing 0.03% w/w of L-DOPA), but not petroleum ether extract, significantly attenuated motor disabilities (akinesia, catalepsy and reduced swim score) and striatal dopamine loss in MPTP treated mice. Since the extract caused significant inhibition of monoamine oxidase activity and attenuated 1-methyl-4-phenyl pyridinium (MPP⁺)-induced hydroxyl radical (·OH) generation in isolated mitochondria, it is possible that the methanolic extract of Hyoscyamus niger seeds protects against parkinsonism in mice by means of its ability to inhibit increased ·OH generated in the mitochondria.     

Phytochemical Profiling by UPLC-ESI-QTOF-MS of Kalaharia uncinata (Schinz) Moldenke,Widely Used in Traditional Medicine in DR Congo

Kalaharia uncinata (Schinz) Moldenke, is a tropical erect bushy shrub or subshrub of the Lamiaceae family. It is an endemic plant species of Southern Africa, widely used in the pharmacopoeia against upper respiratory tract infections. A previously conducted ethnobotanical survey revealed that it is believed to contain bioactive substances. However, no relevant phytochemical information was available. This study aimed to perform a phytochemical characterization of K. uncinata and also to discuss the potential bioactivity of the identified phytochemical constituents based on documented data. Ultra-performance liquid chromatography with electrospray ionization quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) was used for profiling and identification of the main phytochemical constituents from leaf extracts (MeOH 90 %, DCM, AcOEt, BuOH, hexane and residue) of K.uncinata. Twenty-four constituents, representing mainly flavonoids (14), followed by phenylethanoid glycosides (7), phenolic acids (2), and an iridoid glycoside (1) were tentatively identified. Most of the identified compounds are documented to have antiviral and anti-inflammatory properties, which could possibly be the rationale behind the use of K. uncinata against upper respiratory tract infections.     

纳米级南瓜肌醇提取物的制备及其降血糖作用研究

本文通过制备纳米级南瓜肌醇提取物(Nanoscale pumpkin inositol extract,NPIE),观察其对链脲佐菌素诱导的糖尿病模型C57小鼠的血糖调节作用,并与普通南瓜肌醇提取物(Common pumpkin inositol extract,CPIE)的降血糖作用比较。高、低剂量CPIE组和NPIE组分别灌胃500 mg/kg、250 mg/kg的CPIE和NPIE水溶液,阳性药组灌服250 mg/kg的盐酸二甲双胍水溶液,模型对照组灌服等体积的双蒸水,实验周期均为30 d。结果显示所制备的南瓜肌醇提取物含肌醇3.12%,多糖53.21%,其中NPIE粒度平均小于500 nm;经动物实验,各给药组对正常小鼠无明显急性降糖作用,对糖尿病小鼠体重也无影响;但NPIE高剂量组对糖尿病小鼠的随机血糖和空腹血糖均具有明显降低效果,并对其糖耐量有一定改善作用,整体降糖效果较阳性药物组略弱,较CPIE强。     

Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds

In vitro antioxidant activities of three selected Indian red seaweeds - viz., Euchema kappaphycus, Gracilaria edulis and Acanthophora spicifera were evaluated. Total phenolic content and reducing power of crude methanol extract were determined. The antioxidant activities of total methanol extract and five different solvent fractions (viz., petroleum ether (PE), ethyl acetate (EA), dichloromethane (DCM), butanol (BuOH) and aqueous) were also evaluated. EA fraction of A. spicifera exhibited higher total antioxidant activity (32.01 mg ascorbic acid equivalent/g extract) among all the fractions. Higher phenolic content (16.26 mg gallic acid equivalent/g extract) was noticed in PE fraction of G. edulis. Reducing power of crude methanol extract increased with increasing concentration of the extract. Reducing power and hydroxyl radical scavenging activity of E. kappaphycus were higher compared to standard antioxidant (alpha-tocopherol). The total phenol content of all the seaweeds was significantly different (P<0.05). In vitro antioxidant activities of methanol extracts of all the three seaweeds exhibited dose dependency; and increased with increasing concentration of the extract.     

New procedure for isolation of amino acids based on selective hydrolysis of trimethylsilyl derivatives

A rapid procedure for the isolation of amino acids from physiological fluids by class separation suitable for gas chromatographic and gas chromatographic—mass spectrometric analysis is described. A physiological fluid such as plasma is adjusted to pH 2 and extracted with diethyl ether to remove organic acids and neutrals. After precipitation of proteins with trichloroacetic acid, the aqueous plasma is dried and derivatized by trimethylsilylation. Organic compounds like sugars and amino acids are rendered soluble in petroleum ether leaving inorganic salts when the soluble layer is transferred. Separation of sugars from amino acids is achieved by taking advantage of the different rates of aqueous hydrolysis of the trimethylsilyl (TMS) derivatives. Mixing the petroleum ether extract with a small volume of water results in two phases. The petroleum ether layer contains TMS-sugar constituents of plasma and the aqueous layer contains free amino acids and amines. This procedure was used to isolate L-dopa, 3-O-methyldopa and tyrosine from human plasma in a quantitation assay using ¹⁵O-labelled amino acids and gas chromatography—mass spectrometry.