Intracerebroventricular administration of the (1→6)-β-d-glucan (lasiodiplodan) in male rats prevents d-penicillamine-induced behavioral alterations and lipoperoxidation in the cortex

Context: Lasiodiplodan, an exocellular (1→6)-β-d-glucan of molecular weight >1.4?×?10⁶?Da produced by MMPI strain of Lasiodiplodia theobromae (Pat.) Griffon &; Maubl. (Brotyosphaeriaceae) is known to exhibit anti-proliferative activity on breast cancer cells (MCF-7), anticoagulant activity when sulfonylated, and reduction in transaminase activity when administered in rats.

Objective: The effect of intracerebroventricular (I.C.V) injection of lasiodiplodan on neurotoxicity and behavioural changes induced by d-penicillamine was investigated.

Materials and methods: Twenty-four male Wistar rats were initially separated in groups of six and treated with 0.15?μmol/μL of NaCl (Groups Ct and d-Pen) and 0.01?μg/μL of lasiodiplodan (Groups Las and Las?+?d-Pen). After 15?min, they received 6?μmol/μL of NaCl (Groups Ct and Las) and 2?μmol/μL of d-penicillamine (Groups d-Pen and Las?+?d-Pen). The animal behavior was observed in an open-field test for 60?min. Twenty-four h later, the animals were sacrificed and histopathological analysis and Thiobarbituric acid reactive substances (TBARS) production measurements were performed.

Results: Lasiodiplodan prevented neurotoxicity induced by d-penicillamine significantly reducing the production of TBARS (308%; p?Discussion and conclusion: The reduction of TBARS production and convulsive episodes suggests that the protector effect provided by lasiodiplodan passes thought an antioxidant path, possibly interfering in a cascade of neurochemical events, triggering cell death and convulsive episodes. These results demonstrated that lasiodiplodan can be effective in treating neurotoxicity, and reducing damage triggered by convulsions in neuropathies related to GABAergic system.     

Flavonoids,cytotoxic, antioxidant and antibacterial activities of Evax pygmaea

Context: Phytochemical study and biological potential of Evax pygmaea (L.) Brot. (Asteraceae) are reported for the first time.

Objective: To identify the secondary metabolites of Evax pygmaea and to determine its antioxidant, antibacterial and cytotoxic activities.

Materials and methods: Dried aerial parts (1?kg) were macerated in 70% MeOH (5?L) during 72?h. The concentrated hydromethanolic extract was subjected to extractions with chloroform (3?×?300?mL), ethyl acetate (3?×?300?mL) and n-butanol (3?×?300?mL), successively. VLC of combined ethyl acetate (EAEP) and n-butanol (BEP) fractions was followed by column purifications. Antioxidant activity was investigated using DPPH, CUPRAC, and metal chelating, β-carotene/linoleic acid and ABTS assays. Agar method was used in the antibacterial study. Cytotoxic activity was determined by Brine shrimp lethality test in DMSO and ethanol, at varying concentrations (2, 1 and 0.2%) and (1, 0.2 and 0.1%) successively.

Results: Quercetin (1), isorhamnetin 3-O-β-d-xyloside (2), isorhamnetin 3-O-β-d-glucoside (3), quercetin 3-O-β-d-glucoside (4), quercetin 7-O-β-D-glucoside (5), patuletin 3-O-β-d-glucoside (6) were isolated from for the first time from Evax genus. The EAEP was the most active in ABTS (IC₅₀: <3.125?μg/mL) assay whereas the BEEP exhibited the highest activity in the β-carotene/linoleic acid assay (IC₅₀: <3.125?μg/mL). The EAEP and BEP exhibited good antibacterial activity (MIC: 40–80 µg/mL). The plant did not show any toxicity (LD₅₀>80 µg/mL).

Discussion and conclusions: Six flavonoids were isolated for the first time from Evax pygmaea which exhibited good antioxidant and antibacterial activities.     

Compounds from the pods of Astragalus armatus with antioxidant,anticholinesterase, antibacterial and phagocytic activities

Context: The phytochemical study and biological activities of Astragalus armatus Willd. subsp. numidicus (Fabaceae) pods, an endemic shrub of Maghreb, are reported.

Objective: This study isolates the secondary metabolites and determines the bioactivities of Astragalus armatus pods.

Materials and methods: The chloroform, ethyl acetate and n-butanol extracts of hydro-ethanolic extracts were studied. Antioxidant activity was investigated using DPPH and ABTS radical scavenging, CUPRAC and ferrous chelating assays at concentrations ranging from 3 to 200?μg/mL. Anticholinesterase activity was determined against acetylcholinesterase and butyrylcholinesterase enzymes at 50, 100 and 200?μg/mL. Antibacterial activity was performed according to minimum inhibitory concentration (MIC) method. Carbon clearance method in albino mice was used for the phagocytic activity at concentrations 50, 70 and 100?mg/kg body weight. Spectroscopic techniques were used to elucidate the compounds.

Results: Ethyl acetate extract afforded a flavonoid (1) while the n-butanol extract gave four flavonoids (2–5), a cyclitol (6) and a cycloartane-type saponin (7). The ethyl acetate extract exhibited highest antioxidant activity in DPPH (IC₅₀: 67.90?±?0.57?μg/mL), ABTS (IC₅₀: 11.30?±?0.09?μg/mL) and CUPRAC (A_0.50: 50.60?±?0.9?μg/mL) assays. The chloroform extract exhibited the best antibacterial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, each with 80?μg/mL MIC values. The n-butanol extract enhanced phagocytic activity.

Discussion and conclusion: Isorhamnetin (1), isorhamnetin-3-O-α-l-rhamnopyranosyl-(1 → 6)-β-d-galactopyranoside (2), isorhamnetin-3-O-β-d-apiofuranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-galactopyranoside (3), kaempferol-3-O-(2,6-di-O-α-l-rhamnopyranosyl)-β-d-galactopyranoside (4), kaempferol-3-O-(2,6-di-O-α-l-rhamnopyranosyl)-β-d-glucopyranoside (5), pinitol (6) and cyclomacroside D (7) were isolated whereas 1, 2, 6 and 7 are reported for the first time from A. armatus.     

Protein tyrosine phosphatase 1B (PTP1B) inhibitory activity and glucosidase inhibitory activity of compounds isolated from Agrimonia pilosa

Context: Despite phytochemical studies of Agrimonia pilosa Ledeb. (Rosaceae), the antidiabetic effects of this plant are unknown.

Objective: This study characterizes the isolated compounds from the aerial parts of A. pilosa and evaluates their PTP1B and α-glucosidase inhibitory properties.

Materials and methods: Ethanol extract of A. pilosa was found to inhibit 64% PTP1B activity at 30?μg/mL. The ethanol extract was partitioned with methylene chloride, ethyl acetate, n-butanol, and water fractions. Among these, the ethyl acetate fraction displayed the most potent PTP1B activity. The ethyl acetate extract was separated by chromatographic methods to obtain flavonoids and triterpenoids (1–11); which were evaluated for their inhibitory effects on PTP1B activity with p-nitrophenyl phosphate (p-NPP) as a substrate, and also α-glucosidase enzyme.

Results: Compounds 1–11 were identified as apigenin-7-O-β-d-glucuronide-6″-methyl ester, triliroside, quercetin-7-O-β-d-glycoside, quercetin-3-O-β-d-glycoside, kaempferol, kaempferol-3-O-α-l-rhamnoside, β-sitosterol, ursolic acid, tormentic acid, methyl 2-hydroxyl tricosanoate, and palmitic acid. Compounds 8, 9, and 11 displayed inhibitory effects on PTP1B activity with IC₅₀ values of 3.47?±?0.02, 0.50?±?0.06, and 0.10?±?0.03?μM, respectively. Compounds 3, 4, 6, and 9 exhibited inhibition of the α-glucosidase activity with IC₅₀ values of 11.2?±?0.2, 29.6?±?0.9, 28.5?±?0.1, and 23.8?±?0.4?μM, respectively.

Discussion and conclusion: As major ingredients of A. pilosa, compounds 1, 6, 8, and 9 showed the greatest inhibitory potency on PTP1B activity. Compounds 3, 6, 8, and 9 also showed potent inhibitory effects on α-glucosidase enzyme. This result suggested the potential of these compounds for developing antidiabetic agents.     

Antimicrobial and antioxidant effects of phenolic constituents from Klainedoxa gabonensis

Bioassay-guided fractionation of the methanol extract of the stem bark of Klainedoxa gabonensis Pierre ex Engl. (Irvingiaceae) afforded 12 compounds, namely, ellagic acid (1), ellagic acid 3,3′-dimethylether (2), gallic acid (3), methyl gallate (4), lupeol (5), β-amyrin (7), erythrodiol (8), oleanolic acid (9), betulinic acid (6), hederagenin (10), bayogenin acid (11), and stigmasterol-3-O-β-d-glucopyranoside (12). Compounds 1-3 and 7-12 were isolated for the first time from this genus. The structures were established on the basis of 1D/2D NMR experiments and mass spectrometric data. Crude extract, fractions (A, B, C and D) and pure compounds were tested for their antimicrobial activity using paper disk agar diffusion assay. The test delivered a range of low to high activities for phenolic compounds 1-4, low or missing activities for terpenoid compounds 5-11, and impressive very high antibacterial/antifungal values for two fractions C and D probably due to synergistic effects of compounds. The broth microdilution assay revealed MICs of 15.4-115.1?μg/mL for phenolic compounds, MICs higher than 1?mg/mL for terpenoids and MICs of 4.5-30.3?μg/mL for fractions C and D. The determination of the radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay gave high antioxidant values for the methanol extract and fraction D (IC₅₀ 10.45 and 5.50?μg/mL) as well as for the phenolic compounds 1-4 (IC₅₀ 45.50-48.25?mM) compared to the standard 3-t-butyl-4-hydroxyanisole (BHA) (IC₅₀ 44.20?mM).     

Bioactivity-guided isolation and identification of anti-adipogenic compounds from Sanguisorba officinalis

Context: Sanguisorba officinalis Linne (Rosaceae) is a medicinal plant used traditionally for the treatment of inflammatory and metabolic diseases in Korea, China, and Japan. In our previous study, a 50% ethanol extract inhibited fat accumulation in 3T3-L1 adipocytes.

Objective: This study investigates bioassay-guided fractionation, isolation, and identification of anti-adipogenic bioactive compounds in S. officinalis.

Materials and methods: The bioassay-guided fractionation was conducted using effective differentiation of 3T3-L1 cells into adipocytes (with 50?μg/mL test material for 8 days) to isolate the inhibitory compounds from ethyl acetate fraction of S. officinalis 50% ethanol extract. The cytotoxicity of each fraction and isolated compound was tested using MTT assay (with 25–300?μg/mL test material). Structures of the isolated active compounds were elucidated using ¹H NMR, ^13?C NMR, HSQC, HMBC, FT-IR, and MS.

Results: An active ethyl acetate fraction obtained with solvent partition of the extract inhibited lipid accumulation (44.84%) on 3T3-L1 cells without cytotoxicity (102.3%) at the concentration of 50?μg/mL. The ethyl acetate fraction was determined to be mainly composed by isorhamnetin-3-O-d-glucuronide (1) and ellagic acid (2). Pure isorhamnetin-3-O-d-glucuronide (IC₃₀ is 18.43?μM) and ellagic acid (IC₃₀ is 19.32?μM) showed lipid accumulation inhibition on 3T3-L1 cells without cytotoxicity (117.5% and 104.3%) at the concentration of 20?μM, respectively.

Discussion and conclusions: These results suggested that S. officinalis is a potential natural ingredient for the prevention of obesity, which may due to bioactive compounds such as isorhamnetin-3-O-d-glucuronide and ellagic acid.     

Phytolacacinoside A,a new triterpenoid saponin from Phytolacca acinosa Roxb

Phytolacacinoside A (1), a novel triterpenoid saponin, together with the seven known compounds, was isolated from 75% ethanol extract of the root of Phytolacca acinosa Roxb (Phytolaccaceae). Their structures were elucidated on the basis of analysis of spectroscopic data and physicochemical properties as 3-O-β-[(β-d-glucopyranosyl-(1 → 4)-O-β-d-xylopyranosyl)]-11β-methoxy-jaligonic acid 30-methyl ester 28-O-β-d-glucopyranoside (1), 3-O-β-[(β-d-glucopyranosyl-(1 → 4)-O-β-d-xylopyranosyl)]-jaligonic acid 30-methyl ester 28-O-β-d-glucopyranoside (2, esculentoside G), 3-O-β-[(β-d-glucopyranosyl-(1 → 4)-O-β-d-xylopyranosyl)]-jaligonic acid 30-methyl ester (3, phytolaccoside E), 3-O-β-d-xylopyranosyl-jaligonic acid 30-methyl ester (4, phytolaccoside B), hypaphorine (5), palmitic acid monoglyceride (6), β-sitosterol (7), and daucosterol (8).     

Calendula officinalis ameliorates l-arginine-induced acute necrotizing pancreatitis in rats

Context: Calendula officinalis L. (Asteraceae) has been traditionally used in treating inflammation of internal organs, gastrointestinal tract ulcers and wound healing.

Objective: The present study investigates the effect of ethanol extract (95%) of Calendula officinalis flowers in l-arginine induced acute necrotizing pancreatitis in rats.

Materials and methods: Rats were divided into four groups: normal control, l-arginine control, Calendula officinalis extract (COE) treated and melatonin treated (positive control), which were further divided into subgroups (24?h, day 3 and 14) according to time points. Two injections of l-arginine 2?g/kg i.p. at 1?h intervals were administered in l-arginine control, COE and melatonin-treated groups to produce acute necrotizing pancreatitis. Biochemical parameters [serum amylase, lipase, pancreatic amylase, nucleic acid content, total proteins, transforming growth factor-β1 (TGF-β1), collagen content, lipid peroxidation, reduced glutathione and nitrite/nitrate] and histopathological studies were carried out.

Results: COE treatment (400?mg/kg p.o.) was found to be beneficial. This was evidenced by significantly lowered histopathological scores (2 at day 14). Nucleic acid content (DNA 21.1 and RNA 5.44?mg/g pancreas), total proteins (0.66?mg/mL pancreas) and pancreatic amylase (1031.3 100 SU/g pancreas) were significantly improved. Marked reduction in pancreatic oxidative and nitrosative stress; collagen (122 μmoles/100?mg pancreas) and TGF-β1 (118.56?pg/mL) levels were noted. Results obtained were comparable to those of positive control.

Discussion and conclusion: The beneficial effect of COE may be attributed to its antioxidant, antinitrosative and antifibrotic actions. Hence, the study concludes that COE promotes spontaneous repair and regeneration of the pancreas.     

A new eudesmane sesquiterpene glycosides from Liriope muscari

A new eudesmane sesquiterpene glycoside, ophiopogonoside B (1), along with five known compounds, ophiopogonoside A (2), ruscogenin-1-O-[β-d-glucopyranosyl (1 → 2)]-[β-d-xylopyranosyl (1 → 3)]-β-d-fucopyranoside (3), palmitic acid (4), palmitic acid glyceride (5), and β-sitosterol-d-glucopyranoside (6),was isolated from the tuberous roots of Liriope muscari (Decn.) Bailey (Liliaceae). Their structures were confirmed by 1D and 2D NMR spectroscopy. Among them, compounds 1, 2, 4, and 5 were the first reported from the genus Liriope. Ophiopogonoside B (1) showed moderate inhibitory activity to glycogen phosphorylase a.     

Chlorogenic acid protects d-galactose-induced liver and kidney injury via antioxidation and anti-inflammation effects in mice

Context Oxidative stress and inflammation are implicated in the aging process and its related hepatic and renal function decline. Chlorogenic acid (CGA) is one of the most abundant polyphenol compounds in the human diet. Recently, CGA has shown in vivo and in vitro antioxidant properties.

Objective The current study investigates the effects of protective effects of chlorogenic acid (CGA) on d-galactose-induced liver and kidney injury.

Materials and methods Hepatic and renal injuries were induced in a mouse model by subcutaneously injection of d-galactose (d-gal; 100?mg/kg) once a day for 8 consecutive weeks and orally administered simultaneously with CGA included in the food (200?mg/kg of diet). The liver and renal functions were examined. Histological analyses of liver and kidney were done by haematoxylin and eosin staining. The oxidative stress markers and pro-inflammatory cytokines in the liver and the kidney were measured.

Results CGA significantly reduced the serum aminotransferase, serum creatinine (SCr) and blood urea nitrogen (BUN) levels in d-gal mice (p?<0.05). CGA also restored superoxide dismutase, catalase, and malondialdehyde levels and decreased glutathione content in the liver and kidney in d-gal mice (p?<0.05). Improvements in liver and kidney were also noted in histopathological studies. CGA reduced tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) protein levels in the liver and kidney in d-gal mice (p?<0.05).

Discussion and conclusion These findings suggest that CGA attenuates d-gal-induced chronic liver and kidney injury and that this protection may be due to its antioxidative and anti-inflammatory activities.     

Isolation of major phenolics from Launaea spinosa and their protective effect on HepG2 cells damaged with t-BHP

Context: Some Launaea species (Asteraceae) are used traditionally to treat liver oxidative stress.

Objective: The present study investigates the protective effects of isolated compounds from Launaea spinosa Sch. Bip. (Asteraceae) against oxidative stress on t-BHP-induced HepG2 cells.

Materials and methods: Major phenolic content from flowering aerial parts of L. spinosa was isolated and identified. The protective effects of isolated compounds (10 and 20?μM) against oxidative stress induced by tert-butyl hydroperoxide (t-BHP) in HepG2 cells were investigated through the measurement of aspartate aminotransferase (AST), alanine transaminase (ALT), and superoxide dismutase (SOD) levels.

Results: A new phenolic compound identified as 2,3-diferulyl R,R-(+) methyl tartrate (6), in addition to five known metabolites, esculetin (1), esculetin-7-O-d-glucoside (cichoriin) (2), fertaric acid (3), acacetin-7-O-d-glucoside (4), and acacetin-7-O-d-glucuronic acid (5), were isolated. Oxidant-induced damage by 200?μM t-BHP in HepG2 cells was inhibited by compounds 1, 4, and 5 (10 and 20?μM), or quercetin (10?μM; positive control). The protective effects of compounds 1, 4, and 5 were associated with decreasing in AST, ALT, and SOD levels. Compound 4 (20?μM) decreased the AST level from 128.5?±?13.9 to 7.9 ±1.8?U/mL. Meanwhile, compound 1 (20?μM) decreased ALT activity from 20.3?±?7.0 to 7.6?±?2.4?U/mL, while compound 5 decreased SOD levels from 41.6?±?9.0 to 28.3?±?3.4?mU/mg.

Conclusion: The major phenolic compounds isolated from L. spinosa displayed a significant cytoprotective effect against oxidative stress, leading to maintenance of the normal redox status of the cell.     

In vitro and in vivo antidiabetic potential of extracts and a furostanol saponin from Balanites aegyptiaca

Context: Balanites aegyptiaca Del. (Zygophyllaceae) fruits are well-known antidiabetic drug in Egyptian folk medicine. Nevertheless, its mechanism of action is still unclear.

Objectives: Searching for the possible mechanisms of action of the plant and identification of its bioactive compounds.

Materials and methods: A bio-guided protocol based on the evaluation of α‐glucosidase (AG) and aldose reductase (AR) inhibitory activities was adopted to isolate the biologically active compounds from the methanol extract (MeEx). An in vivo antidiabetic study was conducted for the active extract, fraction and compound using streptozotocin-induced diabetic male albino Wistar rats at two dose levels (100 and 200?mg/kg.b/wt) for 2 weeks.

Results: Three compounds were isolated and identified: a sterol, (1) stigmasterol-3-O-β-d-glucopyranoside; a pregnane glucoside, (2) pregn-5-ene-3β,16β,20(R)-trio1-3-O-β-d-glucopyranoside; a furostanol saponin, (3) 26-(O-β-d-glucopyranosyl)-22-O-methylfurost-5-ene-3β,26-diol-3-O-β-d-glucopyranosyl-(1 → 4)-[α-l-rhamnopyranosyl-(1 → 2)]-β-d-glucopyranoside. Only compound 3 possessed significant AG and AR inhibitory activities (IC₅₀?=?3.12?±?0.17 and 1.04?±?0.02?μg/mL, respectively), while compounds 1 and 2 were inactive. The in vivo antidiabetic study revealed that MeEx and furostanol saponin 3 possessed significant activities at a dose of 200?mg/kg through reducing the fasting plasma glucose level by 46.14% and 51.39%, respectively, as well as reducing the total cholesterol by 24.44% and 31.90%, respectively. Compound 3 also caused increment in insulin and C-peptide levels by 63.56% and 65%, respectively.

Discussion and conclusions: We presented a scientific base for using Balanites aegyptiaca, and shed the light on one of its saponins, as an antidiabetic agent in fasting and postprandial hyperglycaemia along with the improvement of diabetic complications.     

A new kaempferol trioside from Silphium perfoliatum

A new apiose-containing kaempferol trioside, kaempferol-3-O-α-l-rhamnosyl-(1? → 6″)-O-β-d-galactopyranosyl-7-O-β-d-apiofuranoside, along with 16 known compounds, were isolated from 50% acetone extract of Silphium perfoliatum L. Their structures were elucidated by acid hydrolysis and spectroscopic techniques including UV, IR, MS, ¹H, ¹³C, and 2D-NMR. In addition, the pharmacological activity of compound 1 was tested with HepG2 and Balb/c mice (splenic lymphocytes and thymic lymphocytes) in vitro, and it exhibited inhibitory effect on the proliferation of HepG2 cells and showed the immunosuppressive activity.     

Two new compounds from Urena lobata L.

Two new compounds 1 and 2 have been isolated from the aerial parts of Urena lobata L. The structures of the two new compounds were established as ceplignan-4-O-β-d-glucoside (1) and 2,5-dihydroxy benzoic acid-7-(2,6-dimethyl-6-hydroxy-2,7-octadienoic acid) anhydride-5-O-β-d-apiofuranosyl(1 → 2)-β-d-glucoside (urenoside A) (2), on the basis of chemical and spectral evidence, including 1D and 2D NMR spectroscopic data as well as mass spectrometry (HR-ESI-MS).     

PTP1B inhibitors from Ardisia japonica

In bioassay-directed isolation from the whole plant of Ardisia japonica, sixteen known compounds: chrysophanol (1), physcion (2), oleanolic acid (3), euscaphic acid (4), tormentic acid (5), quercetin (6), quercitrin (7), myricitrin (8), kaempferol 3-O-α-l-rhamnopyranoside (9), cyclamiretin A 3-O-α-l-rhamnopyranosyl(1→4)-β-d-glucopyranosyl(1→2)-[β-d-glucopyranosyl(1→4)]-α-l-arabinopyranoside (10), (7E)-9-hydroxymegastigma-4, 7-dien-3-on-9-O-β-d-glucopyranoside (11), bergenin (12), norbergenin (13), rutin (14), kaempferol 3,7-O-α-l-dirhamnopyranoside (15), (?)-epigallacatechin 3-O-gallate (16) were obtained. Compounds 1–5, 9, 11 and 14–16 have not been reported previously from this plant. Among these isolates, 2, 3, 6 and 12 showed moderate bioactivity against PTP1B in vitro with IC₅₀ values of 121.50, 23.90, 28.12 and 157?μM, respectively.     

Pregnane glycosides from Solanum nigrum

Two new pregnane saponins, solanigroside A (1) and solanigroside B (2), along with two known compounds (3 and 4), were isolated from 60% ethanolic extract of the dried herb of Solanum nigrum L. The structures of 1 and 2 were elucidated as 5α-pregn-16-en-3β-ol-20-one 3-O-β-d-xylopyranosyl-(1 → 3)-O-[α-l-arabinopyranosyl-(1 → 2)]-O-β-d-glucopyranosyl-(1 → 4)-O-[α-l-rhamnopyranosyl-(1 → 2)]-O-β-d-galactopyranoside (1) and 5α-pregn-16-en-3β-ol-20-one 3-O-β-d-glucopyranosyl-(1 → 2)-O-[β-d-glucopyranosyl-(1 → 3)]-O-β-d-glucopyranosyl-(1 → 4)-O-β-d-galactopyranoside (2), respectively, on the basis of extensive spectroscopic analysis as well as comparison with reported spectroscopic data of related compounds. This paper deals with the isolation and structural characterisation of pregnane glycosides from S. nigrum L.     

Antioxidant and cytotoxic activity of polyphenolic compounds isolated from the leaves of Leucenia leucocephala

Context: Cancer is a serious clinical problem to the health care system. Anticancer drugs have been extracted from plants containing phenolic compounds. Leucenia species (Fabaceae) contain a variety of bioactive components of numerous biological and pharmacological properties.

Objective: This study explored the constitutive polyphenols of Leucenia leucocephala Lam. growing in Egypt and evaluated the antioxidant and cytotoxic activity.

Materials and methods: Chemical structures of the isolated compounds from the leaves of L. leucocephala were established by spectral techniques (UV, ¹H, and ¹³C NMR, MS).

Results: Chromatographic separation of 80% MeOH extract of the leaves of L. leucocephala have resulted in a novel flavonoid-galloyl glycoside [myricetin 3-O-(2′,3′4′-tri-O-galloyl)-α-l-rhamnopyranoside] with three known polyphenolic compounds isolated for the first time from this species (apigenin 7-O-β-d-glucuronopyranoside methyl ester, luteolin 7-O-β-d-glucuronopyranoside methyl ester, and 1,3,6-tri-O-galloyl-β-d-glucopyranose) and seven known previously isolated compounds. Also, 80% methanol extract exhibited high antioxidant activity (SC₅₀?=?3.94 µg/ml), which is correlated with its phenolic content. The extract also showed cytotoxic activity against Hep G2 (IC₅₀ value 1.41 µg/ml) confirming its anticancer activity against hepatocellular carcinoma. Among the tested compounds (4–8) for antioxidant property, compound 7 was the most active compound (SC₅₀?=?2.49 µg/ml). Also compounds 7 and 8 exhibited high cytotoxic activity (IC₅₀?=?2.41 and 2.81 µg/ml, respectively).

Discussion and conclusion: These findings demonstrate that the leaves of L. leucocephala contain a considerable amount of polyphenolic compounds with high antioxidant properties, thus it has great potential as a source for natural health products.     

Compounds from Sedum caeruleum with antioxidant,anticholinesterase, and antibacterial activities

Context: This is the first study on the phytochemistry, antioxidant, anticholinesterase, and antibacterial activities of Sedum caeruleum L. (Crassulaceae).

Objective: The objective of this study is to isolate the secondary metabolites and determine the antioxidant, anticholinesterase, and antibacterial activities of S. caeruleum.

Materials and methods: Six compounds (1–6) were isolated from the extracts of S. caeruleum and elucidated using UV, 1D-, 2D-NMR, and MS techniques. Antioxidant activity was investigated using DPPH^?, CUPRAC, and ferrous-ions chelating assays. Anticholinesterase activity was determined against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes using the Ellman method. Antibacterial activity was performed according to disc diffusion and minimum inhibitory concentration (MIC) methods.

Results: Isolated compounds were elucidated as ursolic acid (1), daucosterol (2), β-sitosterol-3-O-β-d-galactopyranoside (3), apigenin (4), apigetrin (5), and apiin (6). The butanol extract exhibited highest antioxidant activity in all tests (IC₅₀ value: 28.35?±?1.22?µg/mL in DPPH assay, IC₅₀ value: 40.83?±?2.24?µg/L in metal chelating activity, and IC₅₀ value: 23.52?±?0.44?µg/L in CUPRAC), and the highest BChE inhibitory activity (IC₅₀ value: 36.89?±?0.15?µg/L). Moreover, the chloroform extract mildly inhibited (MIC value: 80?µg/mL) the growth of all the tested bacterial strains.

Discussion and conclusion: Ursolic acid (1), daucosterol (2), β-sitosterol-3-O-β-d-galactopyranoside (3), apigenin (4), apigetrin (5), and apiin (6) were isolated from Sedum caeruleum for the first time. In addition, a correlation was observed between antioxidant and anticholinesterase activities of bioactive ingredients of this plant.     

New acylated flavonoid glycosides from flowers of Aerva javanica

Chromatographic purification of ethyl acetate soluble fraction of the methanolic extract of the flowers of Aerva javanica yielded three new acylated flavone glycosides: kaempferol-3-O-β-d-[4?-E-p-coumaroyl-α-l-rhamnosyl(1 → 6)]-galactoside (1), kaempferol-3-O-β-d-[4?-E-p-coumaroyl-α-l-rhamnosyl(1 → 6)]-(3″-E-p-coumaroyl)galactoside (2), and kaempferol-3-O-β-d-[4?-E-p-coumaroyl-α-l-rhamnosyl(1 → 6)]-(4″-E-p-coumaroyl)galactoside (3), along with p-coumaric acid (4), caffeic acid (5), gallic acid (6), eicosanyl-trans-p-coumarate (7), hexadecyl ferulate (8), and hexacosyl ferulate (9). The compounds 1–9 were characterized using 1D (¹H, ¹³C) and 2D NMR (HMQC, HMBC, and COSY) spectroscopy and mass spectrometry (EI-MS, HR-EI-MS, FAB-MS, and HR-FAB-MS) and in comparison with the reported data in the literature. Compound 1 showed weak inhibitory activity against enzymes, such as acetylcholinesterase, butyrylcholinesterase, and lipoxygenase with IC₅₀ values 205.1, 304.1, and 212.3 μM, respectively, whereas compounds 2 and 3 were only weakly active against the enzyme acetylcholinesterase.     

A novel oligosaccharide ester from Syringa pubescens

Pubescenside A (1), a novel oligosaccharide ester, has been isolated from the flowers of Syringa pubescens, together with five known compounds d-mannitol (2), meso-inositol (3), hydrostytosol (4), glucose (5), and sucrose (6). The structure of 1 was elucidated as 1-O-[β-d-glucopyranosyl-(1–6)-β-d-galactopyranosyl-(1–1)-β-d-galactopyranosyl-6]-4,4-dimethylpelargonicate by chemical and spectroscopic means. The water extract of the flowers and leaves of S. pubescens showed cytotoxicity against L2215 cell line (IC₅₀ = 78 μg/ml).