A new Butenolide Derivative from the Brown Alga Sargassum micracanthum

A new butenolide derivative (1), along with three known compounds (2-4) were isolated from the MeOH extract of brown alga Sargassum micracanthum. The structures of 1 to 4 were determined by the analyses of 1D and 2D NMR and mass spectroscopic data. The known compounds (2-4) were identified as (5 E,10 Z)-6,10,14-trimethylpentadeca-5,10-dien-2,12-dione (2), (5 E,9 E)-6,10,14-trimethylpentadeca-5,9-dien-2,12-dione (3), and (-)-loliolide (4) by comparing with their published spectroscopic data. The antioxidant activities of compounds 1 to 4 were evaluated based on using 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities. Compounds 1 to 4 were inactive at the concentration of 200 μM.

Separation and Identification of Antioxidants and Aldose Reductase Inhibitors in Lepechinia meyenii (Walp.) Epling

We previously reported that Lepechinia meyenii (Walp.) Epling has antioxidant and aldose reductase (AR) inhibitory activities. In this study, L. meyenii was extracted in a 50% MeOH and CH2Cl2/MeOH system. The active extracts of MeOH and 50% MeOH were subjected to fractionation, followed by separation using high-speed counter-current chromatography (HSCCC) and preparative HPLC. Separation and identification revealed the presence of caffeic acid, hesperidin, rosmarinic acid, diosmin, methyl rosmarinate, diosmetin, and butyl rosmarinate. Of these, rosmarinic acid, methyl rosmarinate, and butyl rosmarinate possessed remarkable antioxidant and AR inhibitory activities. The other compounds were less active. In particular, rosmarinic acid is the key contributor to the antioxidant and AR inhibitory activities of L. meyenii; it is rich in the MeOH extract (333.84 mg/g) and 50% MeOH extract (135.41 mg/g) of L. meyenii and is especially abundant in the EtOAc and n-BuOH fractions (373.71–804.07 mg/g) of the MeOH and 50% MeOH extracts. The results clarified the basis of antioxidant and AR inhibitory activity of L. meyenii, adding scientific evidence supporting its traditional use as an anti-diabetic herbal medicine. The HSCCC separation method established in this study can be used for the preparative separation of rosmarinic acid from natural products.

Dysidenin from the Marine Sponge Citronia sp. Affects the Motility and Morphology of Haemonchus contortus Larvae In Vitro

High-throughput screening of the NatureBank marine extract library (n = 7616) using a phenotypic assay for the parasitic nematode Haemonchus contortus identified an active extract derived from the Australian marine sponge Citronia sp. Bioassay-guided fractionation of the CH2Cl2/MeOH extract from Citronia sp. resulted in the purification of two known hexachlorinated peptides, dysidenin (1) and dysideathiazole (2). Compound 1 inhibited the growth/development of H. contortus larvae and induced multiple phenotypic changes, including a lethal evisceration (Evi) phenotype and/or somatic cell and tissue destruction. This is the first report of anthelmintic activity for these rare and unique polychlorinated peptides.

Potential anthelmintic and antioxidant activities of Jasminum fruticans L. and its phytochemical analysis

Background: Ethnobotanical investigations conducted in Turkey demonstrated that Jasminum fruticans L. extract and fruit juice had been used against parasites in animals. In this study, the possible antihelmintic activity of various J. fruticans extracts contributing to its traditional use, was relatively assessed. In addition, the antioxidant potentials and phytochemical composition of the extracts were investigated since there is a relationship between helminthiasis, oxidative stress and phenolic metabolites. Methods: In this study, aerial parts of J. fruticans were subsequently extracted using n-hexane, ethyl acetate (EtOAc) and methanol (MeOH). In vivo anthelmintic activitiy of the extracts was compared with albendazole used as a reference in adult earthworms. Various methods, including free radical scavenging and metal-related activity assays, were used to assess the antioxidant capacity of the above-mentioned extracts. Assessment of phenolic composition was accomplished through total phenolic, phenolic acid, and flavonoid content assays as well as liquid chromatography-mass spectrometry (LC-MS/MS) using multiple reaction monitoring (MRM) scan modes. Further chlorogenic acid (3-O-caffeoylquinic acid) contents of extracts were quantified using high-performance thin-layer chromatography (HPTLC). Results: Between all tested extracts, MeOH extract at a quantity of 50.0 mg/mL, paralysed worms in 8.1 min and killed them in 12.8 min, showing a high anthelmintic effect similar to albendazole. Similarly, in vitro DPPH radical scavenging activity, cupric ion reduction and total antioxidant capacity experiments demonstrated that MeOH extract had significant antioxidant activity. Further phytochemical screening showed that MeOH extract was richer regarding phenolic metabolites. Chlorogenic acid, ferulic acid, caffeic acid and gallic acid were only detected in the MeOH extract. Conclusion: Results justify and support the use of J. fruticans in traditional medicine as an anthelmintic agent. Furthermore, a positive correlation was found between the strong antioxidant capacity along with the phenolic composition determined in the MeOH extract and anthelmintic activity.

Phytochemical analysis and antimicrobial and antioxidant activities of Hen-riettea succosa (Aubl.) DC. leaves

Henriettea succosa is a tree species consumed in abundance by birds, however, there is no report on its phytochemical profile and biological activity. This study performed the phytochemical screening and the antimicrobial and antioxidant potential of H. succosa leaves. The hexane (Hex), ethyl acetate (AcOEt) and methanol (MeOH) extracts of the leaves were evaluated for chemical composition by Thin Layer Chromatography and spectrophotometric analysis; the antimicrobial activity was determined by the Minimum Inhibitory Concentration (MIC) and Minimum Microbicide Concentration (MMC); antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, determination of the reducing power and the phosphomolybdenum complex reduction assay. The photoprotor action of the extracts was also evaluated. The results showed a higher content of phenolic compounds (444.08 ± 0.020 mg EAG/g) and tannins (414.37 ± 0.16 mg EAG/g) in the MeOH extract, which was effective against Staphylococcus aureus and Serratia marcescens, with MIC of 1 mg/ ml and CMM of 2 mg/ml. The MIC and MMC of AcOEt for Micrococcus luteus was 1 mg/mL, this was also considered the minimum concentration necessary for the Hex extract to act on the S. aureus strain. The MeOH extract showed greater antioxidant activity by the DPPH (79.09%) and reducing power (327.2 ± 0.00 mg EAA/g) methods, while the AcOEt extract showed greater activity by the phosphomolybdenum method (40.5%). However, none of the extracts showed a photoprotective effect against UV radiation. In summary, this study revealed that the leaves of H. succosa have secondary metabolites with bactericidal potential, in addition to antioxidant action.

Antioxidant and Antibacterial Activity of Yellow Wood (Coscinium fenestratum) Fruits Peel from East Kalimantan

Background: Yellow wood (Coscinium fenestratum) is one of the typical forest plants of East Kalimantan. The hallmark of this plant is the roots, stems and the fruits pulp have a yellow color. There have been many studies on its use and potential in treating liver disease. However, there is limited research about the use of their fruits peel. Objectives: The purpose of this study was as an initial screening of the antioxidant and antibacterial activity from yellow wood (Coscinium fenestratum) fruits peel. Material and Methods: The yellow wood fruits peel was extracted using methanol solvent to obtain the MeOH extract of their fruits peel. The DPPH test was carried out to determined its antioxidant activity (25,50 and 100 ppm). The agar well difusion method was carried out to determined its antibacterial activity. Phytochemical tests are also carried out to determined the secondary metabolites of that fruits peel. Results: The results of the phytochemical test showed that the fruits peel contained alkaloids, flavonoids, carbohydrates, and tannins, but there were no terpenoids or steroids. The fruits peel has an antioxidant activity (58%) at 100 ppm concentration. While the antibacterial test showed strong inhibition at 100 ppm concentration on S. mutans, S. aureus, P. acne and E. coli bacteria. Conclusions: The fruits peel of the yellow wood has compounds that have strong antibacterial activity and medium antioxidant activity.

Aurones and Flavonols from Coreopsis lanceolata L. Flowers and Their Anti-Oxidant, Pro-Inflammatory Inhibition Effects, and Recovery Effects on Alloxan-Induced Pancreatic Islets in Zebrafish

(1) Background: Many flavonoids have been reported to exhibit pharmacological activity; a preparatory study confirmed that Coreopsis lanceolata flowers (CLFs) contained high flavonoid structure content; (2) Methods: CLFs were extracted in aqueous methanol (MeOH:H2O = 4:1) and fractionated into acetic ester (EtOAc), normal butanol (n-BuOH), and H2O fractions. Repeated column chromatographies for two fractions led to the isolation of two aurones and two flavonols; (3) Results: Four flavonoids were identified based on a variety of spectroscopic data analyses to be leptosidin (1), leptosin (2), isoquercetin (3), and astragalin (4), respectively. This is the first report for isolation of 2–4 from CLFs. High-performance liquid chromatography (HPLC) analysis determined the content levels of compounds 1–4 in the MeOH extract to be 2.8 ± 0.3 mg/g (1), 17.9 ± 0.9 mg/g (2), 3.0 ± 0.2 mg/g (3), and 10.9 ± 0.9 mg/g (4), respectively. All isolated compounds showed radical scavenging activities and recovery activities in Caco-2, RAW264.7, PC-12, and HepG2 cells against reactive oxygen species. MeOH extract, EtOAc fraction, and 1–3 suppressed NO formation in LPS-stimulated RAW 264.7 cells and decreased iNOS and COX-2 expression. Furthermore, all compounds recovered the pancreatic islets damaged by alloxan treatment in zebrafish; (4) Conclusions: The outcome proposes 1–4 to serve as components of CLFs in standardizing anti-oxidant, pro-inflammatory inhibition, and potential anti-diabetic agents.

Recovery Effect of a Rutin-Enriched Fraction Prepared From Forsythia koreana Flowers on Alloxan-Induced Pancreatic Islets in Zebrafish Larvae (Danio rerio)

A simple method to prepare a high-content rutin fraction from Forsythia koreana flowers (HRFK) is described. Rutin, isolated for the first time from the flowers, was identified from spectroscopic data including nuclear magnetic resonance, mass spectrometry, and infrared. As a result of HPLC quantitative analysis, the content of rutin was found to be 80.0 ± 0.02% in HRFK. Our previous study reported that F koreana MeOH extract (FK) significantly recovered alloxan-induced pancreatic islets in zebrafish. However, HRFK as well as rutin exhibited an enhanced anti-diabetic effect compared to FK in our latest experiments. In conclusion, HRFK, as well as rutin and FK, have potential as anti-diabetic agents.

Nutritional composition, antioxidant assay and α-glucosidase inhibitory flavonoids from the fruits of Carissa edulis Vahl (Apocynaceae)

Carissa edulis Vahl (Apocynaceae) is a plant whose leaves, roots and fruits are traditionally employed for the treatment of malaria, microbial infections, headache, cough, fever and ulcer among many others. Fresh fruits of Carissa edulis were crushed and extracted with 70 % methanol for 72 hours to obtain MeOH extract. Proximate analysis as well as mineral composition of the fresh fruits were determined. Total phenolic content (TPC), total flavonoids content (TFC) and antioxidant activity (DPPH, FRAP & Ferrous chelating) of the MeOH extract were determined, while the α-glucosidase inhibitory activity of the extract was conducted using bioautographic assay. The structure of compounds isolated were elucidated by 1D NMR spectroscopic analysis and high-resolution mass spectrometric (HRESIMS) data. The results showed that the nutritive value of the fresh Carissa edulis is 43.43 kcal/100 g, while the extract demonstrated good antioxidant activities (DPPH, IC50 = 87.98 μg/ml; FRAP, EC50 = 464.33 μg/ml & Ferrous chelating, EC50 = 294.55 μg/ml). Further study of the MeOH extract of the fruit led to the isolation of rhamnetin-3-β-D-glucopyranoside, peonidin-3-rutinoside and malvidin-3-O-β-D-(6”-acetylglucoside). These results suggest that the fruits of Carissa edulis are nutritious and possess potential antidiabetic effect which corroborated the ethnomedical uses of the fruits. Keywords: Carissa edulis; α-Glucosidase; Anthocyanins; Nutritional composition; Antioxidant properties

Determination of the Chemical Composition, Antioxidant, and Enzyme Inhibitory Activity of Onosma mollis DC

Onosma species have long been used traditionally for respiratory tract infections, abdominal pain, wound treatment, burns, and constipation. This study aims to investigate the chemical composition and in vitro antioxidant and enzyme inhibitory activities of ethyl acetate (EtOAc), methanol (MeOH), and water extracts of Onosma mollis DC. MeOH extract was richer in both phenolics and flavonoids than other extracts (44.06 mg GAEs/g and 41.57 mg QEs/g, respectively). The findings obtained from the results of the chromatographic analysis also supported the results of the spectrophotometric analysis. The MeOH extract was the richest in terms of most of the phytochemicals screened. Apigenin 7-glucoside, luteolin 7-glucoside, rosmarinic acid, vanillic acid, and pinoresinol were over 1000.0 μg/g in MeOH extract. The extract in question showed the highest activity in phosphomolybdenum, DPPH, and ABTS radical scavenging and CUPRAC and FRAP reducing power activity assays (2.01, 3.33, 2.30, 1.48, and 0.79 mg/ml, respectively). The water extract presented the highest activity in the ferrous ion chelating assay (1.01 mg/ml). While EtOAc extract showed high activity in acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase inhibitory activity tests (1.11, 1.49, and 1.07 mg/ml, respectively), MeOH extract showed significant efficacy in tyrosinase and α-amylase inhibitory activity assays (2.94 and 2.08 mg/ml, respectively). There was a high correlation between the total phenolics/flavonoids of the extracts and their antioxidant activities (correlation coefficients were over 0.9). In addition, the phytochemicals mentioned above were found to contribute significantly to the antioxidant activity. It was concluded that a more detailed analysis should be done to determine the compounds responsible for the enzyme inhibitory activities of the extracts.