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Endophytes provide mutual benefits and produce various biologically active secondary metabolites in plants. Our study was designed to isolate and identify fungal endophytes from fresh leaf and bark of Tinospora cordifolia, coupled with their bioactivity and preliminary chemical screening. Six endophytic fungi were isolated using surface sterilization technique. The fungi were identified by microscopic and molecular characterization and confirmed TCLE-1 as Fusarium perseae, TCLE-2 as Fusarium keratoplasticum, TCLE-3 as fusarium macrosporum, TCBE-1 as Fusarium falciforme and TCBE-2 as well as TCBE-3 leaving unidentified. Isolated strains were cultured in large scale on potato dextrose agar (PDA) medium and were extracted using ethyl acetate. Antibacterial activity of fungal extracts was performed by disc diffusion method and cytotoxicity using HeLa cell line by MTT assay. In antimicrobial test, all the fungal extracts except TCBE-2 showed moderate to potent activity in comparison to the standard kanamycin. All, except TCBE-2, demonstrated significant cytotoxic activity on HeLa cell. Preliminary chemical profiling using thin liquid chromatography (TLC) and analytical high performance liquid chromatography techniques indicated the presence of secondary metabolites in fungal extracts. In conclusion, endophytic fungi reside in the T. cordifolia, a native medicinal plant in Bangladesh, could be a potent source of putative antibacterial and anticancer compounds. Dhaka Univ. J. Pharm. Sci. 21(2): 183-194, 2022 (December)

This study was conducted to discover wide spectrum of endophyte diversity from the Zingiber officinale Rosc. Endophytic fungi were obtained from different plant tissues. All the isolated strains were identified up to genus level following described colony morphology. The recognized five different morphotypes were subjected to sequence analysis of internal transcribed spacer (ITS) gene. Fusarium proliferatum, Fusarium solani and Cladosporium cladosporoides were identified based on comparison of the BLAST results and phylogenetic identification. The presented study provides the comprehensive explanation of the interrelation of morphological and molecular homologies for the identification of the prospective fungi. Bangladesh J. Plant Taxon. 29(2): 361-371, 2022 (December)

Withania somnifera (Ashwagandha) is used in medicine from the time of Ayurveda. The roots of the plant are used traditionally in the treatment of nervous and some other disorders. Several effects like immunomodulation, hypolipidemic, antibacterial, cardiovascular protection, tolerance and dependence have also been studied. Many Studies show that ashwagandha comprises antioxidant, anxiolytic, adaptogen, memory enhancing, antiparkinsonian, antivenom, anti-inflammatory, antitumor properties. This article is presented to gather all the updated information on its phytochemical profile and its endophytic fugal communities. The review result indicates the herb of Withania somnifera (Ashwagandha) should be studied more extensively to confirm the earlier studied results and reveal other capable therapeutic effects.

Numerous biologically active metabolites have previously been obtained from endophytes including endophytic fungi. This potentiality and prospect prompted us to find out new compounds having activity against pathogenic bacteria, from fungal endophyte, Necterium sp. isolated from the leaf of Tinospora cordifolia. We cultivated and developed the fungal strains on PDA medium and extracted on ethyl acetate after 28 days. Column chromatographic technique followed by preparative TLC was utilized to isolate secondary metabolites as pure crystalline solid. Two naphthoquinones namely anhydrofusarubin (1) and fusarubin methyl ether (2) were isolated from Necterium sp. The 1H and 13C NMR spectral data of the isolated compounds were analyzed and compared with previously published values to confirm the structure of the compounds. The compounds were assessed for antibacterial activity by resazurin based microdilution assay. Both of them showed sensitivity towards gram negative Pseudomonas aeruginosa but none was active against Staphylococcus aureus, a gram positive bacteria. The MIC values against P. aeruginosa for anydrofusarubin (1) and fusarubin methyl ether (2) were found to be 32- and 64-μg/ml respectively while the standard gentamycin showed MICs of 6.25 μg/ml (for S. aureus) and 12.5 μg/ml (for P. aeruginosa). The outcomes of our study suggest that anhydrofusarubin (1) and fusarubin methyl ether (2) are beneficial lead compounds to broaden the sphere of marketed antibacterial drugs. Bangladesh Pharmaceutical Journal 25(1): 80-88, 2022 (January)

Background Due to increasing number of individuals within the world having health issues caused by varied cancers, drug-resistant microorganism, parasitic protozoans, and fungi could be a cause for alarm. Endophyte’s are a unique source of medicinal compounds which requires an intensive seek for newer and simpler agents to handle these sickness issues is currently advancing. This study explores the description of endophytic fungi of Ceriops decandra (Griff.) W. Theob., a mangrove plant growing in mangrove forest, Sundarban, Bangladesh. Methods The endophytic fungi of experimental plants were identified by DNA amplification and sequencing of the internal transcribed spacer (ITS) region Moreover, cytotoxicity, antioxidant and antimicrobial tests were assessed. In addition, the screening of extracts was performed by visual detection using UV light. Results Three fungi namely CEDBE-1, CEDLE-6 and CEDLE-10 (internal strain no) were isolated as endophytic fungi and identified as Fusarium oxysporum, Clonostachys spp. and Fusarium solani respectively on the basis of morphological characteristics and DNA sequencing. The isolates were cultured at 280 C±2 for 21 days in Potato Dextrose Agar (PDA) media. The extracts of fungal isolates were examined at 100 µg/disc concentration for the screening of antibacterial activity and exhibited no activity against tested human pathogenic bacteria. The strain CEDBE-1 showed highest antioxidant activity of IC50 value of 31.07 µg/mL comparing with the positive control ascorbic acid (0.74) and BHA (7.79) µg/mL. All isolates exhibited strong cytotoxic activity using brine shrimp lethality bioassay compared with the positive control tamoxifen. Preliminary chemical screening of the fungal extracts by thin layer chromatography technique revealed the presence of various compounds. Conclusions The findings indicate that endophytic fungal isolates explored from C. decandra has diversified biological activities which may be potential source of leads for new drug development.

This study describes the development and validation of a simple, specific, accurate, and precise method for quantitative determination of Esomeprazole in human serum using Pantoprazole as internal standard (IS). After the addition of internal standard, Esomeprazole from serum samples was extracted simply by protein precipitation method followed by centrifugation and the supernatants were directly injected into the high performance liquid chromatography (HPLC). The chromatographic separation of the compounds was obtained on Hitachi Lachrom C8 column (5 µm, 250 × 4.6 mm) with a mobile phase consisting of 5 mM potassium dihydrogen phosphate pH 7.4 and acetonitrile in a ratio of 70:30 with UV detection at 302 nm with a flow rate of 1 mL/min. The method was sensitive and specific, and validated over a concentration range of 0.06–6.0 µg/mL. The limit of detection (LOD) and lower limit of quantification (LOQ) was 0.03 µg/mL and 0.06 µg/mL, respectively. The precision and accuracy expressed as relative standard deviation were less than 15%. The average recovery of Esomeprazole from serum was 97.08%.

Present work describes the isolation and morphological identification of endophytic fungi from Phyllanthus niruri L. including their chemical and bioactivity screening. Two isolated and purified endophytic fungi with the internal strain numbers PNRE and PNLE were taxonomically identified as Colletotrichum sp. and Fusarium sp., respectively. Preliminary chemical screening of the fungal extracts through thin layer chromatography (TLC) revealed the presence of various components. PNLE showed significant antifungal activity against the fungi Aspergillus niger (24 mm) and Aspergillus flavus (20 mm). Extracts of PNRE and PNLE gave significant cytotoxic activity with LC50 values of 1.08 μg mL-1 and 1.05 μg mL-1, respectively in the brine shrimp lethality bioassay. PNRE extract showed mild scavenging of DPPH with IC50 value of 96.06 μg mL-1 during antioxidant activity screening. Crystal formation was observed in the crude PNRE fungal extract which was purified using methanol/dichloromethane (0-20%) to obtain pure white crystal and the structure was elucidated by NMR (1H NMR and 13C NMR) spectroscopic analysis to be confirmed as ergosterol. Since isolated fungi showed promising antifungal and cytotoxic activities, the crude extract of endophytic fungi of P. niruri could be considered as a promising source for isolation of potential bioactive compounds. Bangladesh J. Sci. Ind. Res.55(4), 311-318, 2020

Endophytic fungi are a group of fungi that reside in the living plant without causing any disease symptoms. It shows symbiotic/mutualistic characteristics with host plants. Endophytic fungi may increase the host defense system against various pathogenic microorganisms and may encompass secondary metabolites of respective host plants. Isolation of endophytic fungi and its metabolites from Justicia gendarussa plant grown in Bangladesh is a recent and new approach. A total of seven endophytic fungi were isolated and purified from the leaf and bark part of the plant. All of the isolated endophytic fungi were identified up to genus level on the basis of macroscopic and microscopic characteristics and up to species level on the basis of molecular characteristics as Colletotrichum gloeosporioides, Diaporthe pseudomangiferae, Pseudopestalotiopsis camelliae-sinensis, Colletotrichum gloeosporioides, Fusarium solani, Colletotrichum tropicale and Colletotrichum siamense. Preliminary chemical screening of the fungal extracts by thin-layer chromatographic technique revealed the presence of various compounds such as flavonoids, anthraquinones, couramins, isocoumarins etc. Fungal strain Pseudopestalotiopsis camelliae-sinensis exhibited significant antiradical activity through DPPH scavenging method and moderate antimicrobial activity against a wide range of human pathogenic microbes. Using brine shrimp lethality bioassay, all the isolates showed strong cytotoxic activity, therefore suggested that all the extracts may have bioactive metabolites. Overall, these findings indicate that Justicia gendarussa and its associated endophytic fungi could be an important source for exploring potentially bioactive compounds or leads for the new drug candidates.

A new dimeric prenylated quinolone alkaloid, named 2,11-didemethoxy-vepridimerine A, was isolated from the root bark of Zanthoxylum rhetsa, together with thirteen known compounds. The structure of the new compound was elucidated on the basis of spectroscopic investigations (NMR and Mass). The interaction of the isolated compounds with the main protease of SARS-CoV-2 (Mpro) was evaluated using molecular docking followed by MD simulations. The result suggests that 2, 11-didemethoxy- vepridimerine A, the new compound has the highest negative binding affinity against the Mpro with free energy of binding of-8.5 Kcal/mol indicating interaction with the Mpro. This interaction was further validated with the help of MD simulation using remdesivir, one of the currently approved drugs against SARS-CoV-2, as a control.

Endophytic fungi reside in the intercellular space of plant nourished by the plant. In return, they provide bioactive molecules which can play critical roles on plant defense system. Fifty six endophytes were isolated from the leaves, root, bark and fruits of Sonneratia apetala, a pioneer mangrove plant in the Sundarbans, Bangladesh. A total of 56 isolates were obtained and 12 different species within 8 genera were identified using morphological and molecular characteristics. Antimicrobial activity of Ethyl Acetate (EtOAc) and Methanolic (MeOH) extracts of these 12 different species were analyzed by resazurin assay and the Minimum Inhibitory Concentrations (MICs) were determined. The fungal extracts showed antimicrobial activities against more than one tested bacterium or fungus among 5 human pathogenic microbes, i.e. Escherichia coli NCTC 12241, Staphylococcus aureus NCTC 12981, Micrococcus lutus NCTC 7508, Pseudomonas aeruginosa NCTC 7508 and Candida albicans ATCC 90028. Overall, Methanolic extracts showed greater activity than that of Ethyl Acetate extracts. Of the isolates identified, Colletotrichum gloeosporioides, Aspergillus niger and Fusarium equiseti were the most active isolates and showed activity against microorganisms under investigation. Methanolic extracts of C. gloeosporioides and A. niger showed the lowest MIC (0.0024 mg/mL) against Pseudomonas aeruginosa. The study indicates that endophytic fungi isolated from S. apetala species posses potential antimicrobial properties, which could be further investigated.

The objective of this study is to isolate, identify and investigate the pharmacological activities of the endophytic fungi from an aquatic plant Aponogeton undulatus Roxb. (A. undulatus). Endophytic fungi were isolated and identified based on morphological characters. The molecular identification of the fungal isolates was performed using by analyzing the DNA sequence based on mega BLAST program. Spectrums of antibacterial and antifungal activities were studied by Agar diffusion methods. Extracts of the endophytic fungal strains isolated from the plant A. undulatus were screened for probable cytotoxic activities using brine shrimp lethality bioassay. Six endophytic fungi, namely AULE-1, AULE-2, AULE-3, AURE-1, AURE-3 and AURE-4 were isolated and purified from the leaves and roots of the plant such as strains AULE-1 as Trichooderma sp., AULE-2 as Carvularia sp. AULE-3 as Penicillium sp. strains AURE-1 and AURE-4 as Fusarium sp. and AURE-3 as Mucor sp. Strain AURE-4 was further identified as Fusarium solani. At 300 μg/disc concentration, six ethyl acetate extracts of endophytic fungi of the plant A. undulates showed moderate to significant activities against most of the test bacteria and pathogenic fungi. The strain AURE-4 exhibited strong cytotoxic activities (10.18 μg/mL) compared to the standard antitumor agent vincristine sulphate and this positive result suggests that fungal extracts may contain antitumor or pesticidal compounds. This is the first study to report the isolation, identification, antimicrobial and cytotoxic properties of endophytic fungi of Aponogeton undulatus Roxb. in Bangladesh.

The antioxidant and anti-inflammatory potential of Heritiera fomes ethanolic extract was evaluated.Query Ethanolic extraction of dried and grinded plant leaves and bark was performed. Antioxidant activity was evaluated by 1, 1-diphenyl-2-picryl-hydrazil (DPPH) free radical scavenging assay, ferric reducing antioxidant power (FRAP) and β-carotene bleaching inhibition assay. Total phenolic and flavonoid content were also determined. Anti-inflammatory activity was evaluated by in vitro human RBC membrane stabilizing assay and in vivo mice paw edema test. Ethanolic bark and leaf extracts of H. fomes (S1 and S2, respectively) showed significant scavenging effect on DPPH scavenging 68.51 µg/ml for S1 and 108.64 µg/ml for S2. Potent reduction potential (FRAP) was observed in S1 (83.75 mM of ferrous equivalent) while the FRAP of standard ascorbic acid was found 86.66 μM of ferrous equivalent. S1 also exhibited 87.43% β-carotene bleaching inhibition as comparable to standard butylated hydroxytoluene with 98.85% inhibition. Substantial phenolic and flavonoid content was also observed in S1 (136.83 μg gallic acid equivalent/g of extract and 76.67 μg quercetin equivalent/g of extract, respectively). S1 could provide 61.73% and 53.27% protection of RBC membrane in hypotonicity and heat induced lysis of RBC, respectively while the standard diclofenac sodium provided 91.66% and 86.66% protection, respectively. Furthermore, 44.16% reduction in mice paw edema at 40 μg/kg bw concentration was observed in S1 as compared to standard indomethacine (53.54% in 10 μg/kg bw concentration). The results revealed that the bark extract (S1) of H. fomes possesses significant antioxidant and anti-inflammatory activity.

Objectives: The possible phytochemical constituents, thrombolytic and membrane stabilizing activities of the crude ethanolic extract of Enhydra fluctuans (CE) were investigated along with the antimicrobial, antioxidant and cytotoxic potentials of its petroleum ether (PESF), carbon tetrachloride (CTCSF), chloroform (CSF) and aqueous (AQSF) soluble fractions. Materials & Methods: The coarse leaf powder was extracted at room temperature with ethanol. Solvent-solvent partitioning was done to obtain the four soluble fractions. Anticoagulant potential was determined by the in vitro thrombolytic model, membrane stabilization method was used to assess in vitro anti-inflammatory activity, the disc diffusion method was used for anti-microbial screening, antioxidant potential was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method and brine shrimp lethality bioassay method was used for cytotoxic activity determination. Results: Chemical screening of the crude extract evidenced the presence of alkaloids, saponins, tannins, flavonoids, reducing sugars and gums. It showed significant clot lysis property of 46.91%. It also significantly inhibited heat and hypotonic solution induced lysis of the human red blood cell membrane with values of 71.80% and 47.60%, respectively. CTCSF and PESF showed mild antimicrobial activity. AQSF showed most prominent antioxidant activity with IC50 value of 12.27 µg/mL. CTCSF showed LC50 value of 0.84 µg/mL, with most potent cytotoxic activity. Conclusion: Significant thrombolytic, membrane stabilizing, antioxidant and in vitro cytotoxic activities of the ethanolic plant extract were observed in this study. In vivo activities and isolation of active compound(s) from this extract are yet to be investigated.

A reverse phase liquid chromatographic method for estimation of Aceclofenac in bulk drug and tablet dosage form was developed and validated. The chromatographic conditions to achieve the highest performance parameters using octylsilyl column with guard filter were optimized. The separation was carried out using a mobile phase containing 10 mM Phosphate Buffer, pH 2.1 and methanol (30:70% v/v) pumped at a flow rate of 1.0 mL/min with detection at 272 nm. The method was shown to be linear in 19.8–148.5 μg/mL concentration range (regression coefficient of 0.999). The limit of detection (LOD) and limit of quantification (LOQ) was found to be 0.0692 μg/mL and 0.2076 μg/mL, respectively. The accuracy of the method was assessed by adding fixed amount of pre-analyzed sample to different standard solutions (80%, 100%, and 120% of the tested concentration) in triplicate. The percentage mean recoveries were 97.91% to 100.39% with %RSD values of 0.64–0.79. The method was found to be precise with %RSD value of 1.13 and 1.60 for intraday and interday precision study, respectively. The method specificity and robustness were also established. New and sensitive HPLC method for estimation of Aceclofenac has been developed, in respect to the reviewed analytical methods.

Commelina diffusa Burm. F. is a herbaceous tropical plant with different traditional medicinal uses. Present study is aimed to isolate the bioactive compounds from DCM-Methanol extract of the powdered whole plant of Commelina diffusa and to investigate the cytotoxic, antimicrobial and antioxidant activities of the crude extract and its twelve vacuum liquid chromatographic fraction (CD1-12). Vacuum Liquid Chromatography (VLC) was employed to isolate bioactive metabolites. The physicochemical properties of the isolated compound were examined and the molecular structure was elucidated by NMR spectroscopy. Cytotoxic, antibacterial, antioxidant activities were evaluated following brine shrimp lethality bioassay, disc diffusion method and DPPH free radical scavenging assay respectively. The isolated compound was identified as steroid (stigmasterol) which had significant cytotoxic effect on vero cell line. The crude extract and its fractions (CD8-CD12) exhibited strong cytotoxicity in brine shrimp lethality bioassay having LC50 values 3.79, 9.19, 29.49, 16.60, 19.36, 44.58 μg/mL respectively. The crude extract showed mild to strong antibacterial activity. Fractions (CD5-CD12) showed mild to strong antibacterial activity against Escherichia coli in comparison with Kanamycin (standard). Strong antioxidant activities were found in crude extract (IC50 value 30.52 μg/ml), CD11 (IC50 value 39.27 μg/ml) and CD12 (IC50 value 19.50 μg/ml). The study suggests Commelina diffusa plant extract to have strong antioxidant and cytotoxic activity which is indicative of presence of compounds with broad spectrum of curative applications. One compound namely stigmasterol has been isolated from the plant.

Endophytes (both fungi and bacteria) represent a treasure house for bioactive compounds such as anticancer, immunomodulatory, antioxidant, antiparasitic, insecticidal etc. for use in the pharmaceutical and agrochemical industries. Endophytic population is greatly influenced by climatic conditions and location where the host plant grows. Curcuma longa L. (Turmeric) is a medicinal plant belonging to the Zingiberaceae family that is usually used as spice and preservative. Traditionally it is used to treat various conditions and symptoms such as digestive disorders, arthritis, cardiovascular conditions, cancer, bacterial infections etc. In recent times, there have been different discoveries on endophytic fungi and their biological activity from C. longa. But there is no comprehensive review on endophytic fungi of C. longa. The aim of this review is to analyze the published report based on the endophytic fungi to provide for the first time an updated information about their isolation from different tissues, their biological activities including the phytochemistry of C. longa. This will lead the way to forecast the missing link for future research work.

A mangrove medicinal plant Cynometra ramiflora (Family: Leguminosae) was selected to investigate the bioactivities namely antioxidant, antimicrobial and preliminary cytotoxic activity using methanol and chloroform extracts of the leaves and stems, respectively. In 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, 50% inhibitory concentration (IC50) of the methanolic stem extract was found to be 31.62 µg.mL-1. Reducing power of the same extract demonstrated consistent increase in a concentration-dependent manner and was comparable with quercetin while ferric reducing antioxidant power (FRAP) assay revealed potential total antioxidant capacity (84.0 mM Fe (II)/g of extract). In addition, the presence of total phenolics (96.2 mg GAE/g of extract), total flavonoids (166.4 mg QE/g of extract) and tannins content (80.4 mg GAE/g of extract) were determined in the methanolic stem extract. The chloroformic stem extract exhibited moderate antimicrobial activity against a number of bacterial strains while the MIC values of extracts were in the range from 62.5 to 500µg.mL-1. The methanolic stem and leaf extracts demonstrated strong lethality in preliminary cytotoxicity assay using brine shrimp nauplii where the 50% lethal concentration (LC50) values were 1.596 and 4.613 µg.mL-1 respectively. It can be therefore concluded that the methanolic extracts of C. ramiflora possess potential antioxidant, antimicrobial and strong preliminary cytotoxic activity and could be further exploited for prospective scientific exploration towards bioactive principles.

Objectives: This work describes the chemical and in-vitro bioactivity studies on endophytic fungi derived from the leaves of Carica papaya L. Methods: Column Chromatography was employed for isolation of fungal metabolites. Nuclear Magnetic Resonance (NMR) spectral data was utilized to elucidate the structure of the isolated compounds and physicochemical properties of them were also examined. As a part of in-vitro bioactivity screening disc diffusion method, 1, 1-diphenyl-2- picryl-hydrazyl (DPPH) scavenging assay and brine shrimp lethality bioassay were conducted to evaluate antimicrobial, antioxidant and cytotoxic activities, respectively. Results: A total of four fungal isolates were identified as endophytic fungi and purified from the young leaves of Carica papaya. These fungi, encoded as CPLE-1, CPLE-2, CPLE-3 and CPLE-4, were identified up to the genus level on the basis of their macroscopic and microscopic characteristics as Colletotrichum sp., Carvularia sp., and next two as Alternaria sp., respectively. Chemical profiling and preliminary bioactivity screening of the fungal endophytes signified strain CPLE-3 with highest potentiality to produce bioactive compounds which directs its large scale cultivation. Ergosterol and Alternariol monomethyl ether were isolated from the ethyl acetate extract of the fungus, CPLE-3. Conclusion: Bioactivity and chemical screening of the endophytic fungal extracts of Carica papaya leaf along with the isolation of fungal secondary metabolites suggested these endophytic fungi to be possible source of bioactive leads for developing new and improved medicines.

A stability-indicating UV/Vis spectrophotometric method was developed and validated for estimation of diazepam in tablet dosage form. The proposed method utilized a Specord 250 plus PC double beam spectrophotometer using 1.0 cm quartz cells and all determinations were made at a wavelength of 231 nm in 1:1 methanol:distilled water. Experiments were designed for determining linearity, limit of detection and quantitation, accuracy, precision and specificity of this analytical method as per the International Organization for Standardization guidelines. The drug substance and the drug product were exposed to thermal, photolytic, hydrolytic, and oxidative stress conditions, and the stressed samples were analyzed using the proposed method to demonstrate the specificity of the method. The proposed method was found to be linear in the concentration ranges from 3.096-15.480 µg/ml with the linear correlation coefficient of R2= 0.999 and the mean recoveries were 98.36 to 100.72 %. Although the degradation products of stressed condition had not been identified, the method had been able to detect the changes due to stress condition. The stated method can be used as stability indicating method with high degree of linearity, accuracy and precision for assay of diazepam in routine pharmaceutical analysis of tablets.

Article history: The research work was involved in rapid and efficient procedure for the attachment of barbituric acid with arylidene acetophenone under microwave irradiation (MWI) and conventional heating. The result showed that the time was reduced from the conventional 24 hours to 5-10 minutes. In conventional heating, the yield of the compounds 2a-2e were very poor (75-81%), but in MW methods the yields were observed 96.48-98% which was comparatively too high. The structures of the compounds were characterized by FT-IR, 1 H-NMR spectral data. The antimicrobial and cytotoxic activities of the synthesized compounds were also investigated. Staphylococcus aureus, Bacillus megaterium, Escherichia coli and Pseudomonas aeruginosa revealed the zone of inhibition were 6-12 mm where sample concentration was 100 μg/disc. However, cytotoxic analysis, the mortality 47-95% were appeared when sample concentration were 0.78-25 (μg/ml) and more than 50 (μg/ml) concentration showed 100% mortality. The presence of a reactive and unsaturated ketone function in synthesized compounds was found to be responsible for their potential antimicrobial and cytotoxic activity.

Bioactivity-guided fractionation of the ethyl acetateextract obtained from the culture of the endophytic fungus Fusariumsolani resulted in the isolation of one new naphthoquinone, 9-desmethylherbarine (1), and two azaanthraquinone derivatives, 7-desmethylscorpinone (2) and 7-desmethyl-6-methylbostrycoidin(3), along with four known compounds. Their structures wereelucidated by spectral analysis, as well as a direct comparison ofspectral data with those of known compounds. Azaanthraquinones 2and 3 showed cytotoxic activity against four human tumor cell lines,MDA MB 231, MIA PaCa2, HeLa, and NCI H1975. A moleculardocking study suggested DNA interactions as the mode of action of these naphthoquinones and azaanthraquinones.

Four compounds were isolated from the petroleum ether and ethyl acetate extracts of the stem bark of Hopea scaphula Roxb. The structures of the isolated compounds were elucidated as stigmasterol (1), 1,2- dimethoxy-4-allylbenzene (2), 3,4-dimethoxycinnamaldehyde (3) and fi-amyrin (4) by extensive spectroscopic studies. The isolated compounds and crude extracts were subjected to antioxidant screening through free radical scavenging activity by DPPH (1, 1-diphenyl-2-picrylhydrazyl), where compounds 1 and 2 showed substantial antioxidant activity with IC50 value 18.0 and 63.0 fig/ml, respectively. In case of fi-glucosidase inhibition assay, the ethyl acetate extract revealed strong inhibitory activity (94.18%) while the petroleum ether extract showed 79.11% enzyme inhibition. This is the first report of antioxidant and fi-glucosidase inhibitory activities of H. scaphula Roxb

Six compounds, namely, Lupeol (1), Betulin (2), beta-Taraxerol (3), Taraxerone (4), Stigmasterol (5) and beta-Sitosterol (6) were isolated from the petroleum ether extract of the leaves of Sapium baccatum based on spectroscopic evidence. Lupeol (1), Betulin (2) and Stigmasterol (5) were isolated for the first time from this plant. The cytotoxic potential of the different solvent extracts (methanol, petroleum ether, carbon-tetrachloride and dichloromethane); six column fractions (F-4, F-7, F-10, F-12, F-18 and F-22) of petroleum ether extract and three pure compounds 1, 4 and 6 were determined by using brine shrimp lethality bioassay. The LC50 of all the tested samples were showed to be lethal to brine shrimp nauplii. However, petroleum ether, carbon-tetrachloride extract, column fractions F-4 and F-18 of petroleum ether extract and pure compound 6 showed quite potent activity in brine shrimp lethality bioassay with LC50 1.33, 1.35, 1.40, 1.58 and 1.58 microg/ml, respectively. These result suggested that they might be contain antitumor or pesticidal activity. Further, the methanol extract and four column fractions (F-7, F-12, F-18 and F-22) of petroleum ether showed significant activity against the tested microorganisms.

Callophylum symingtonianum (Guttiferae), an evergreen broad-leaved tree that usually grows in hill forests, can be found distributed in the Malay Peninsula. The barks, leaves, flowers and seeds is often used medicinally to treat diarrhea and rheumatism. In the present study, we isolated two inophyllum type coumarins, 12-O-ethylinophyllum D (1) and iso-soulattrolide (2) from the stembarks of C. symingtonianum together with their antibacterial activity. The compounds were isolated by chromatographic methods on a silica gel. The structures were established by spectroscopic methods including UV, IR, (1D and 2D) NMR and mass spectrometry as well as by comparison with several literature sources. The antibacterial activity of those compounds was tested using a disc-diffusion assay against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeruginosa. Both compound exhibited mild inhibition against P. aeruginosa with both 111 µg/ml MIC value. Compound 2 also inhibits S. aureus with 25 µg/ml MIC value.

The petroleum ether and ethanol extracts of Vitex trifolia leaves exhibited moderate inhibiting activity against both gram-positive and gram-negative bacteria.

The antibacterial activity of different crude extracts of Clausena heptaphylla leaves as well as three purified coumarins, obtained from the cold methanol extract, is reported.

The petroleum ether extract of the leaves of Clausena heptaphylla afforded a new coumarin, lunamarin C (1). Its structure was determined by extensive analysis of spectral data, including 2D NMR and by comparison with structurally related compounds, lunamarins A (2) and B (3).

Two new bioactive metabolites 1a and 2a (dinemasones A, B) were isolated in pure form and one as the diacetate 3b of dinemasone C (3a) from the ethyl acetate extract of Dinemasporium strigosum together with the known palmitic acid, ergosterol and the cis and trans isomers of 4-hydroxymellein. The structures were determined by spectroscopic analysis, notably 2D NMR techniques. Their absolute configurations were established by both their carbonyl n–π* CD transitions and the exciton chirality method of their respective dibenzoate derivatives. The dinemasones A, B (1a and 2a) showed antibacterial, antifungal, and antialgal activity.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

not available DOI: http://dx.doi.org/10.3329/dujs.v61i2.17074 Dhaka Univ. J. Sci. 61(2): 213-214, 2013 (July)

Six known metabolites, two new isocoumarins 4 and 8, and one new highly substituted benzoic acid derivative 9 were isolated from the ethyl acetate culture extract of a fungal endophyte, Scytalidium sp. In addition, another new benzoic acid 10 with an unusual 1,2-dicarbonyl side chain was indirectly identified from its methylated derivatives 10a–10d.