α-Glucosidase inhibitory activity of marine sponges collected in Mauritius waters

This report describes the use of α-glucosidase to evaluate the anti-diabetic potential of extracts from marine sponges collected in the Mauritius waters. Initial screening at 1.0 mg/mL of 141 extracts obtained from 47 sponge species revealed 10 extracts with inhibitory activity greater than 85%. Seven of the 10 extracts were further tested at 0.1 and 0.01 mg/mL and only the methanol extract of two sponges namely Acanthostylotella sp. (ASSM) and Echinodictyum pykei (EPM) showed inhibition activity greater than 60% at 0.1 mg/mL with an IC₅₀ value of 0.16 ± 0.02 and 0.04 ± 0.01 mg/mL, respectively, while being inactive at 0.01 mg/mL.     

The polysaccharide extracts from the fungi Coprinus comatus and Coprinellus truncorum do exhibit AChE inhibitory activity

The polysaccharide (PSH) extracts from the edible mushroom species Coprinus comatus and Coprinellus truncorum were screened in liquid for their acetylcholinesterase inhibitory (AChE) activity. Both extracts were found to display inhibition of the aforementioned enzyme reaching similar IC₅₀ values of 0.62 ± 0.07 and 0.61 ± 0.03 mg/mL, respectively. According to the means of FTIR spectroscopy, these PSH extracts mostly contained β-glucans. However, the presence of some proteins and polyphenolics as minor ingredients were also detected. Compared with existing literature data for anti-AChE activity of the sugar samples, the findings within this study may be treated as a profound bioactivity. Consequently, this study puts some light on the possible use of the screened macrofungi in the palliative treatment of Alzheimer’s disease.     

An insight into antimicrobial activity of the freshwater bryozoan Pectinatella magnifica

The antimicrobial activity of five crude extracts of the freshwater bryozoan Pectinatella magnifica (Leidy, 1851) was evaluated in vitro for the first time. P. magnifica acetone extract exhibited the highest antibacterial activity (minimum inhibitory concentrations (MIC) 0.004–0.350 mg/mL and MBC 0.007–0.500 mg/mL), while its methanol extract showed the most promising antifungal activity (MIC 0.03–0.12 mg/mL and MFC 0.06–0.25 mg/mL). Furthermore, at a concentration of 0.25 MIC, the methanol extract reduced biofilm formation of the bacterial strain Pseudomonas aeruginosa PAO1 in a considerable extent (59.14%). FTIR spectra of the most active extracts indicate the presence of carbonyl compounds, long-chain alcohols and/or sterols. According to the experimental data obtained, P. magnifica methanol extract may be considered as a good resource of novel natural products with potent antibiofilm activity against the bacterium well known for its resistance.     

In vitro antimicrobial activity of extracts and compounds isolated from Cladonia uncialis

Heptane (Hep), diethyl ether (Et₂O), acetone (Me₂CO) and methanolic (MeOH) extracts, as well as ( ? )-usnic acid and squamatic acid, were obtained from thallus of Cladonia uncialis (Cladoniaceae). The antimicrobial activities of these extracts, ( ? )-usnic acid and squamatic acid, were tested against reference strains: Staphylococcus aureus, Escherichia coli and Candida albicans. In addition, Me₂CO extract was analysed against 10 strains of Methicillin-resistant S. aureus (MRSA) isolated from patients. All extracts exerted antibacterial activity against the reference strain S. aureus, comparably to chloramphenicol [minimum inhibitory concentration (MIC) = 5.0 μg/mL]. The Me₂CO extract exhibited the strongest activity against S. aureus (MIC = 0.5 μg/mL), higher than ( ? )-usnic acid, whereas squamatic acid proved inactive. The Me₂CO extract showed potent antimicrobial activity against MRSA (MIC 2.5–7.5 μg/mL). Also no activity of C. uncialis extracts against E. coli and C. albicans was observed.     

Biological activity and LC-MS/MS profiling of extracts from the Australian medicinal plant Acacia ligulata (Fabaceae)

Acacia ligulata A.Cunn. ex Benth. (Fabaceae: Mimosoideae) is a native Australian plant used traditionally by Australian Aboriginal groups. This study was undertaken to investigate the bioactivity of A. ligulata extracts and to evaluate their chemical composition. Potential antibacterial, cytotoxic and enzyme inhibitory effects relevant to traditional medicinal and food uses of the species were examined and LC-MS/MS was performed to investigate the chemical composition. Antibacterial activity was observed for bark and leaf extracts with an MIC for the bark extract of 62.5 μg/mL against Streptococcus pyogenes. Pod extracts showed cytotoxic effects against cancer cells, with the highest activity against melanoma SK-MEL28 cells with IC₅₀ values between 40.8 and 80.6 μg/mL. Further, the leaf and pod extracts also inhibited α-amylase EC-3.2.1.1 and α-glucosidase EC-3.2.1.20 with IC₅₀ values between 9.7–34.8 and 12.6–64.3 μg/mL, respectively. The LC-MS/MS profiling indicated that several different saponins were present in the active extracts.     

Flavonoids from Plinia cauliflora (Mart.) Kausel (Myrtaceae) with antifungal activity

Plinia cauliflora is a plant species with edible fruits but its chemical composition is not totally known yet although former studies showed its potential as antifungal agent. This work aimed the chemical analysis of the leaves, the activity against fungi species and evaluated cytotoxicity. Extract was obtained with 70% ethanol. An ethyl acetate fraction was obtained and glycosylated quercetin and myricetin were isolated. Samples were tested against Candida species, dermatophytes and entomopathogenic fungi. Cytotoxicity was evaluated against fibroblast cells. Extract showed good activity against C. albicans (minimum inhibitory concentration at 156 μg/mL), C. parapsilosis (78 μg/mL), C. krusei (19 μg/mL), Trichophyton rubrum (78 μg/mL) and Microsporum canis (156 μg/mL). Isolated compounds were more active against C. krusei and T. rubrum. The extract, which was the more active sample, demonstrated low cytotoxic effect and encourage more studies against rising non-albicans species and dermatophyte T. rubrum.     

Phenolic content and in vitro antifungal activity of unripe grape extracts from agro-industrial wastes

The antifungal activity of unripe grape extracts from agro-industrial wastes has been evaluated against several strains of Candida spp. and dermatophytes. All the extracts tested showed antifungal activity. The geometric mean MIC ranged from 53.58 to 214.31 μg/mL for Candida spp. and from 43.54 to 133.02 μg/mL for dermatophytes. The chemical analyses have been carried out using Liquid Chromatograph equipped with a DAD and MS detectors. Flavan-3-ols were the main metabolites within all samples ranged from 3.3 to 6.8 mg/g fresh weight. For Candida spp. highest negative significant correlation has been found between MICs and polymeric flavan-3-ols (r = ?0.842; p < 0.001) and for dermatophytes between MICs and caffeoyl derivatives (r = ?0.962; p < 0.01). The results indicate that total extracts obtained from unripe grapes, a large source of waste material derived from the wine industry, could be used as a cheap source of value-added products.     

Antioxidant,antimicrobial and urease inhibiting activities of methanolic extracts from Cyphostemma digitatum stem and roots

Cyphostemma digitatum stem and roots extracts were investigated for antioxidant, antimicrobial, urease inhibition potential and phytochemical analysis. Phytochemical screening of the roots and stem extract revealed the presence of secondary metabolites including flavonoids, alkaloids, coumarins, saponins, terpenoids, tannins, carbohydrates/reducing sugars and phenolic compounds. The methanolic extracts of the roots displayed highest antioxidant activity (93.518%) against DPPH while the crude methanolic extract of the stem showed highest antioxidant activity (66.163%) at 100 μg/mL concentration. The methanolic extracts of both stem and roots were moderately active or even found to be less active against the selected bacterial and fungal strains (Tables S2 and S3). The roots extract (methanol) showed significant urease enzyme inhibition activity (IC₅₀ = 41.2 ± 0.66; 0.2 mg/mL) while the stem extract was found moderately active (IC₅₀ = 401.1 ± 0.58; 0.2 mg/mL) against thiourea (IC₅₀ = 21.011; 0.2 mg/mL).     

Previously undescribed antioxidative azocinyl morpholinone alkaloid from red seaweed Gracilaria opuntia with anti-cyclooxygenase and lipoxygenase properties

In vitro antioxidative and anti-inflammatory bioassay-guided fractionation of the methanol: ethyl acetate crude extract of the thalli of red seaweed Gracilaria opuntia collected from the Gulf of Mannar led to the isolation of a new morpholine alkaloid 3-(2-ethyl-6-((3Z,7Z)-1,2,5,6-tetrahydroazocin-5-yl)hexyl) morpholin-6-one. The substituted azocinyl morpholinone recorded significant 1,1-diphenyl-2-picryl-hydrazil free radical scavenging activities (IC₅₀ ~ 0.086 mg/mL) compared to the commercially available antioxidants, butylated hydroxyanisole, butylated hydroxytoluene, and α-tocopherol (IC₅₀ > 0.20 mg/mL). The title compound showed greater cyclooxygenase-2 (COX-2) inhibitory activity (IC₅₀ 0.84 mg/mL) in conjunction with in vitro 5-lipoxidase inhibitory activity (IC₅₀ 0.85 mg/mL) than non-steroidal anti-inflammatory drugs (NSAIDs). The test compound had better selectivity index (COX-1/COX-2 ratio) (1.17 mg/mL) compared to aspirin (0.02 mg/mL), Na salicylate (0.73 mg/mL) and ibuprofen (0.44 mg/mL). The animals challenged with the substituted azocinyl morpholinone significantly mitigated the carrageenan-induced paw edema in time-dependent manner till the end of 6 h.     

Quantification of polyphenols and flavonoid content and evaluation of anti-inflammatory and antimicrobial activities of Stenocereus stellatus extracts

The hexanic, ethyl acetate and methanolic extracts from branches of Stenocereus stellatus were tested in both the 12-O-tetradecanoylphorbol-13-acetate (TPA) – induced ear oedema model and antimicrobial activity assay. The % of oedema inhibition, the Minimum Inhibitory Concentration (MIC), as well as the polyphenolic and flavonoid content were determined. Also, extracts were analysed by gas chromatography–mass spectrometry (GC–MS). In TPA model, the three extracts showed moderate oedema inhibition. In the antimicrobial activity assay, methanolic extract shows better MIC against all strains. The lowest MICs were for Candida albicans (31 μg/mL) and Rhizopus sp. (15 μg/mL). Also, 50.78 mg eq. of gallic acid/g extract of polyphenol and 115.12 mg eq. of catequine/g extract of flavonoids content were founded in ethyl acetate extract. In the chromatographic analysis, β-sitosterol, β-amyrine, betulin and some other molecules were identified. The results show that S. stellatus possess antimicrobial activities against some fungus species.     

Phytochemical profile and biological activities of Deverra tortuosa (Desf.)DC.: a desert aromatic shrub widespread in Northern Region of Saudi Arabia

The present study describes the chemical composition of the essential oil of different plant parts of Devrra tortuosa; in vivo and in vitro biological activities of plant extract and essential oils. Apiol was found to be the major component of the oil (between 65.73% and 74.41%). The best antioxidant activities were observed for the oil of flowers (IC50 = 175 μg/ml). The samples of stems and roots exhibit lower antioxidant activity (IC50 = 201 μg/ml and 182 μg/ml, respectively). The values of IC50 showed that the extracts of methanol exhibit the highest antioxidants activities (IC50 = 64.8 102 μg/ml). EOs showed excellent antifungal activity against yeasts with low azole susceptibilities (i.e. Malassezia spp. and Candida krusei). The MIC values of oils varied between 2.85 mg/mL and 27 mg/mL. The obtained results also showed that the plant extracts inhibited the germination and the shoot and root growth of Triticum æstivum seedlings.     

Anticholinesterase,antioxidant activity and phytochemical investigation into aqueous extracts from five species of Agrimonia genus

Aqueous extracts of aerial flowering parts of five Agrimonia species (Rosaceae): Agrimonia coreana Nakai, Agrimonia japonica (Miq.) Koidz, Agrimonia procera Wallr., Agrimonia eupatoria L. and Agrimonia leucantha Kunze were investigated on their antioxidant activity, measured using five different methods; the best was the extract from A. procera with IC₅₀ values from 6 to 29 μg/mL. All the extracts displayed inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) at the tested concentration of 100 μg/mL. We found the highest inhibition of cholinesterase in the extract of A. japonica with inhibition 70.4% for AChE and 79.8% for BuChE. These findings are statistically significant in comparison with those of other extracts (p < 0.001). The phytochemical analyses showed that the antioxidant activity of Agrimonia extracts can be affected especially by hexahydroxydiphenoyl (HHDP)-glucose and quercetin glycosides, and inhibition of cholinesterases by apigenin, luteolin and quercetin glycosides.     

HPTLC analysis of Scoparia dulcis Linn (Scrophulariaceae) and its larvicidal potential against dengue vector Aedes aegypti

This study evaluates the larvicidal activity of Scoparia dulcis aqueous extract against dengue vector and determines its major chemical components. The extract was tested at various concentrations ranging from 0.1 to 2 mg/mL against Aedes aegypti larvae. The extracts displayed significant larvicidal efficacy against Ae. aegypt species after 24 h exposure revealing LC₅₀ of 3.3835 (mg/mL) and LC₉₀ of 5.7578 (mg/mL). Finger printing profile carried out by CAMAG automatic TLC sample applicator programmed through WIN CATS software revealed peaks with different R_f values for three different volumes injected: 16, 15 and 18 peaks were spotted for 3, 6 and 9 μL, respectively. Ascending order of R_f values was also ascertained for each peak recorded. This study clearly signifies that S. dulcis extract contains numerous compounds that are known to have larvicidal properties which clearly substantiates its efficacy on Ae. aegypti larvae.     

Modulation of antibiotic activity by the hydroalcoholic extract from leaves of Caryocar coriaceum WITTM

The aim of this study was to identify the presence of tannins, phenols and flavonoids on the hydroalcoholic extract of Caryocar coriaceum leaves (HECCL) and to determine the antioxidant and antibacterial activity of this extract. The extract was tested alone (1024–1 μg/mL) or associated (MIC/8) with several antibiotics in order to identify any antibacterial activity against multiresistant bacterial strains (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa). The existence of tannins, total phenols (901.31 mg/g) and flavonoids (89.68 mg/g) was confirmed in the HECCL. The presence of rutin and quercetin were confirmed by Thin-layer chromatography (TLC). Using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, the antioxidant activity of the extract (9 μg/mL) was determined. Moreover, the Minimum Inhibitory Concentration (MIC) value found for HECCL was 1024 μg/mL and the association between HECCL (MIC/8) with benzylpenicillin significantly changed its minimum inhibitory concentration from 2500 to 625 μg/mL against E. coli.     

Chemical constituents of essential oil of endemic Rhanterium suaveolens Desf. growing in Algerian Sahara with antibiofilm,antioxidant and anticholinesterase activities

Twenty compounds were detected in the essential oil of Rhanterium suaveolens representing 98.01% of the total oil content. Perillaldehyde (45.79%), caryophyllene oxide (24.82%) and β-cadinol (5.61%) were identified as the main constituents. In β-carotene–linoleic acid assay, both the oil and the methanol extract exhibited good lipid peroxidation inhibition activity, with IC₅₀ values of 17.97 ± 5.40 and 11.55 ± 3.39 μg/mL, respectively. In DPPH and CUPRAC assays, however, the methanol extract exhibited a good antioxidant activity. The highest antibiofilm activity has been found 50.30% against Staphylococcus epidermidis (MU 30) at 20 μg/mL for essential oil and 58.34% against Micrococcus luteus (NRRL B-4375) at 25 mg/mL concentration for methanol extract. The in vitro anticholinesterase activity of methanol extract showed a moderate acetylcholinesterase inhibitory (IC₅₀ = 168.76 ± 0.62 μg/mL) and good butyrylcholinesterase inhibitory (IC₅₀ = 54.79 ± 1.89 μg/mL) activities. The essential oil was inactive against both enzymes.     

Phytochemical composition,in vitro antioxidant activity and antibacterial mechanisms of Neolamarckia cadamba fruits extracts

Aqueous extracts of Neolamarckia cadamba fruits prepared at different maturity stages were used for the analysis of various phytochemicals, and their antioxidant and antibacterial activities were determined. Ripe fruit extract had highest phenolics (3.14 mM GAE/ g fruit extract) with caffeic acid, tannic acid, syringic acid and quercetin as major phenolic compounds. The ripe fruit extract showed lowest IC₅₀ values in DPPH radical scavenging assay (231.33 μg fruit extract/ mL), and highest ABTS radical scavenging activity (111.18 μM TEAC/g). Immature fruit extract showed lowest minimum inhibitory concentration against tested bacteria, and the antibacterial activity was probably due to membrane permeation, as was evident by leakage of genetic material and reduction in propidium iodide uptake by bacterium; and by inhibition of sugar and amino acid uptake. The appreciable amount of phenolic compounds and biological activities in the aqueous extracts of N. cadamba fruits suggests it's potential application as natural preservative.     

Chemical constituents of the fermentative extracts of marine fungi Phoma sp. CZD-F11 and Aspergillus sp. CZD-F18 from Zhoushan Archipelago,China

A new diphenyl ether (1) as well as 20 other compounds were identified from the fermentative extracts of marine-derived fungi Phoma sp. CZD-F11 (Compounds 1–8) and Aspergillus sp. CZD-F18(Compounds 9–21). Their structures were elucidated on the basis of extensive spectroscopic analysis. The broth extracts of the fungi exhibited very good anticancer activity against H1975 cells with 5.62 and 25.8% viability at concentration of 10 μg/mL for Phoma sp. CZD-F11 and Aspergillus sp. CZD-F18, respectively. The inhibitory activity of all compounds against PC-3 cell lines, BRD4 and aromatase were evaluated. The results showed compound 7 exhibited moderate anticancer activity with 66.1% inhibition against PC-3 cell lines at the concentration of 10 μg/mL. Compound 7 and 8 exhibited favourable BRD4 inhibitory activity with 78.5 and 76.4% inhibition at the concentration of 10 μg/mL.     

Antifungal activity of extracts from Cynomorium coccineum growing wild in Sardinia island (Italy)

Cynomorium coccineum L. is a non-photosynthetic plant, spread over Mediterranean countries, amply used in traditional medicine. The aim of this study was to evaluate for the first time the antifungal activity of its extracts. The antifungal activity was evaluated using the macrodilution method against Candida spp., Cryptococcus neoformans and dermatophyte strains. The methanolic extract was very active against C. neoformans, Candida guilliermondii and Candida krusei, with minimal inhibitory concentrations (MIC) values of 0.025 mg/mL. This extract is more active than fluconazole against C. krusei H9. The influence of methanolic extract on the dimorphic transition in Candida albicans was also studied through the germ tube inhibition assay. More than 60% of filamentation was inhibited at a concentration of 1/4 MIC. These results are preliminary and further studies are needed to an eventual use of C. coccineum methanolic extract in the treatments of candidiasis and cryptococcosis.     

GC–MS characterisation and biological activity of essential oils from different vegetative organs of Plectranthus barbatus and Plectranthus caninus cultivated in north Italy

Essential oils (EOs) from the roots, stems and leaves of Plectranthus barbatus (A) and Plectranthuscaninus (B), cultivated in north Italy, were obtained by steam distillation and chemically characterised by gas chromatography–mass spectrometry. The highest yields were obtained from roots (268.15 and 673.60 mg/kg from A and B), followed by leaves (64.34 and 26.65 mg/kg) and stems (19.76 and 18.63 mg/kg). A total of 128 structures were identified in A and 121 in B. Fe⁺⁺ chelating and antiradical activities (DPPH and ABTS) were evaluated: root and stem EOs showed the strongest activities, while EOs from leaves did not show relevant activities. All EOs were tested for their in vitro antimicrobial activity, showing optimal growth-inhibition in antibiogram (?>35 mm) and MIC tests (32–64 μg/mL) against Candida albicans, while EOs from leaves of both species showed a good activity (25 < ? < 34 mm, MIC 64–128 μg/mL) against Escherichia coli.