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Three previously undescribed diterpenoids, propadanes A-C (1-3), together with seventeen known compounds (4-20), were isolated from the rhizomes of Kaempferia elegans and Kaempferia pulchra. The structures of the isolated compounds were elucidated through extensive analysis of spectroscopic data. The absolute configuration (12R) of propadane A (1) was established by CD analysis. (−)-Kolavelool (15) and (−)-2β-hydroxykolavelool (18) showed selective cytotoxic activity against the HL-60 cell line with IC50 values of 8.97 ± 0.66 and 9.58 ± 0.88 μg/mL, respectively. Anticopalic acid (5), anticopalol (10), and 8(17)-labden-15-ol (11) showed antimicrobial activity against the Gram positive bacterium, Bacillus cereus, with MIC values of 3.13, 6.25, and 6.25 μg/mL, respectively. Labdane-type diterpenoids were found to be common constituents in K. elegans, while clerodane-type diterpenoids were common in K. pulchra. This information could be used to establish their chemotaxonomy.

Twenty previously unknown compounds and two known metabolites, merulin A and merulin D, were isolated from the endophytic fungus Pseudolagarobasidium acaciicola, which was isolated from a mangrove tree, Bruguiera gymnorrhiza. Structures of the 20 compounds were elucidated by analysis of spectroscopic data. The absolute configuration of seven of these compounds was addressed by a single crystal X-ray analysis using CuKα radiation and an estimate of the Flack parameter. Three compounds also possessed a tricyclic ring system. Terpene endoperoxides isolated exhibited cytotoxic activity, while those without an endoperoxide moiety did not show activity. The endoperoxide moiety of sesquiterpenes has significant impact on cytotoxic activity, and thus is an important functionality for cytotoxicity. One terpene endoperoxide displayed potent cytotoxic activity (IC50 0.28μM), and selectively exhibited activity against the HL-60 cell line.

During functionalization at C2, C3, and C4 of quinoline, we came across a one-step metal free synthesis of C3 quinolinium derivatives of mesomeric betaine dyes. Some mesomeric betaine dyes had solvatochromic properties, and were sensitive to pH and solvates in the water. Certain betaine dyes had different properties in acidic and basic environments; the reversible interconversion between yellow (neutral or basic condition) and colorless (acidic condition) forms of the dye occurs by pH change. The changes in UV absorbance intensities of the dyes in the presence of cyclodextrins indicated the inclusion complex formation between cyclodextrins and dyes. The betaine dyes were partially dissolved in water due to the presence of positive and negative charges in the molecule. These betaine dyes did not exhibit cytotoxic activity, hence may be used in biological research.

Various classes of natural products and synthetic compounds were tested against reference strains and clinical multidrug resistant isolates of Mycobacterium tuberculosis. Vermelhotin (19), a natural tetramic acid from fungi, was the most active toward clinical MDR TB isolates (MIC 1.5-12.5 μg/mL). Synthetic compounds (i.e. benzoxazocines, coumarins, chromenes, and pyrrolodiquinoline derivatives) were prepared by green chemistry approaches. Under microwave irradiation, a one-pot synthesis of pyrrolodiquinoline 85 was achieved by homocoupling of 1-methylquinolinium iodide; the structure of 85 was confirmed by single-crystal X-ray analysis. Compound 85 and its derivative 86 exhibited potent anti-tubercular activity (MIC 0.3-6.2 μg/mL) against clinical MDR TB isolates, and they displayed weak cytotoxicity toward normal cell line. The scaffold of 85 and 86 is potential for antimycobacterial activity.

Polyketides 1-6 were produced by a one strain-many compounds (OSMAC) approach using the endophytic fungus Dothideomycete sp. CRI7 as a producer. Metabolite production of the fungus Dothideomycete sp. CRI7 was sensitive to sources of potato and malt extract used for the preparation of PDB and Czapek malt media, respectively. Three hitherto unknown metabolites were obtained from the fungus CRI7 grown in PDB medium prepared from a commercial potato powder instead of fresh tubers of potato, while three others were obtained from the fungus cultivated in Czapek malt medium. Moreover, a source of malt extract used in the Czapek malt medium was found to influence metabolite production by the fungus CRI7. Structure elucidation of these compounds was achieved by analysis of spectroscopic data, as well as by single crystal X-ray analysis. Two of the compounds showed weak cytotoxic activity, while the remainders were inactive toward the cell lines tested. One compound exhibited radical scavenging activity with an IC50 value of 21.7 μM, and inhibited aromatase with an IC50 value of 12.3 μM.

Vernonia extensa, known as “Phim Phai Lin” in Thai, is distributed in most regions of Thailand. The plant has been used in Ayurveda and traditionally used to treat malaria and cancer, and possesses several sesquiterpene lactones. This study aimed to investigate and identify the active constituents by bioactivity-based analysis, as well as to evaluate the cytotoxic activity of V. extensa by MTT or XTT assays in ten cancer cell lines (Liver HepG2 and S102; Bile duct HuCCA-1; Leukemia HL-60 and MOLT-3; Lung A549 and H69AR; Breast MDA-MB-231 and T47D; Cervical HeLa). Bioactivity-guided fractionation and semi-preparative HPLC purification were used to separate the bioactive constituents. Apoptosis-inducing activity and cell cycle inhibitory effect of selected active compounds were determined on HepG2 cells by flow cytometric analysis. Bioactivity-guided fractionation of the CH2Cl2 extract and chemical investigation of the cytotoxic fractions led to the isolation of a new sesquiterpenoid pseudo-dimer named vernodalidimer L, together with eight known sesquiterpenoids from the aerial part of V. extensa. The structures of the isolates were elucidated based on spectroscopic analysis, including 1D and 2D NMR and HRMS. Vernolide has potent broad-spectrum cytotoxicity with IC50 values in the range of 0.91–13.84 μM, against all ten cancer cell lines. The annexin-V flow cytometric analysis showed that vernodalin, vernolepin, and vernolide induced apoptosis on HepG2 cells in a dose dependent manner and these effects correlated with G2/M phase cell cycle arrest. Our results indicated that vernodalin, vernolepin, and vernolide have potential to be used as lead compounds in the development of a therapeutic natural product for treatment of liver cancer.

Aim of study This study screened for anthelmintic and/or antitumour bioactive compounds from Thai indigenous plants and evaluated effectiveness against three different worm species and two cancer cell lines. Materials and methods Methylene chloride and methanol extracts of 32 plant species were screened for in vitro anthelmintic activity against three species of worms, the nematode Caenorhabditis elegans, the digeneans Paramphistomum epiclitum and Schistosoma mansoni (cercariae). Cytotoxicity of the extracts was evaluated against two cancer cell lines: human amelanotic melanoma (C32) and human cervical carcinoma (HeLa) by the SRB assay. Anthelmintic and anticancer activities were evaluated by the inhibiting concentration at 50% death (IC50) and the selectivity index (SI) relative to human fibroblasts. Results and conclusions None of the extracts were active against Paramphistomum epiclitum. Plumbagin, a pure compound from Plumbago indica, had the strongest activity against Caenorhabditis elegans. The methylene chloride extract of Piper chaba fruits had the strongest activity against schistosome cercariae. Strong cytotoxicity was shown by the methylene chloride extract of Michelia champaca bark and the methanol extract of Curcuma longa rhizome against C32 and HeLa, respectively. These extracts had higher SI (>100) than positive controls in relation to either the worms or the cell lines. The methanol extract of Bouea burmanica had a slightly lower activity towards C32 cells than did Michelia champaca but had a much higher SI (>27,000). Ethnopharmacological relevance The plant species screened in this research was recorded by several indigenous medicinal practitioners as antiparasitic, anticancer and/or related activities to the human major organ system.

The endophytic mitosporic Dothideomycete sp. LRUB20 was found to produce pyrone derivatives, dothideopyrones A-D (1, 3, 4, and 5), together with seven known compounds, including questin (9), asterric acid (10), methyl asterrate (11), sulochrin (12), and eugenitin (13), 6-hydroxymethyleugenitin (14), and cis, trans-muconic acid (15). Dothideopyrone D (5) and its acetate derivative 6 exhibited moderate cytotoxic activity. This is the first report on a naturally occurring muconic acid, which is commonly known as a biomarker in environments after exposure to benzene and phenol (or derivatives). Interestingly, the LRUB20 fungus could produce muconic acid in relatively high yield (47.8mg/L). The utility of endophytic fungi in the field of white biotechnology is discussed.

The amino acid residues serine at position 213 (S213) and lysine at position 218 (K218), which are present in close proximity to the histidine-rich motif II of Mucor rouxii fatty acid Delta(6)-desaturase isoform II, were targeted for studying structure-function relationships using site-directed mutagenesis. The mutants were functionally characterized in a heterologous host, Saccharomyces cerevisiae. Substrate specificity and preference studies revealed that S213 and K218 are involved in substrate recognition. K218 plays a role in substrate preference by involvement in the binding of substrates, particularly C15-C18 monoene fatty acids. Modification of the M. rouxii Delta(6)-desaturase therefore has potential in specifically altering substrate utilization for production of desired fatty acids.

The total synthesis of antimalarial and cyclooxygenase inhibitors, racemosol and de- O -methylracemosol, is described. The key steps involved the lateral lithiation reaction of ortho -methyl tolulate and the pyran formation via a tandem demethylation–cyclization reaction.

Azaphilone pigments, monascusones A (1) and B (2), together with two known azaphilones, monascin (3) and FK17-P2b2 (4), were isolated from the CH2Cl2 extract of a yellow mutant of the fungus M. kaoliang grown on rice. Structures of the isolated compounds were elucidated by analyses of spectroscopic data. Monascusone A (1), the major metabolite of M. kaoliang, showed no antimalarial (against Plasmodium falciparum), antitubercular (against Mycobacterium tuberculosis H37Ra), and antifungal (toward Candida albicans) activities. Compound 1 exhibited no cytotoxicity against BC (breast cancer) and KB (human epidermoid carcinoma of cavity) cell lines.

Nitrones are formed from the reaction of aspergillusol A ( 1 ) and a ketone/aldehyde in phosphate buffer and aqueous solutions with pH ranges of 6.8–8.6, resembling physiological conditions. The reaction of 1 with 1-substituted cyclohexanones gave the (1′ S ∗ ,2′ R ∗ )-isomer, diastereoselectively.

Precursor-directed biosynthesis of beauvericin analogs, cyclohexadepsipeptide antibiotics, was investigated using the insect pathogenic fungus Paecilomyces tenuipes BCC 1614. Feeding l -isoleucine or d -alloisoleucine in liquid medium led to the enhanced production of beauvericin A and beauvericin B together with beauvericin and a missing analog, beauvericin C. Feeding experiments with d -isoleucine or l -alloisoleucine resulted in the production of diastereomers of beauvericins A, B and C, named allobeauvericins A, B and C, respectively.

The C-4 sulfated isoflavonoid, torvanol A (1), and the steroidal glycoside, torvoside H (3), together with the known glycoside, torvoside A (2), were isolated from a MeOH extract of Solanum torvum fruits. Upon enzymatic hydrolysis with beta-glucosidase, torvoside A (2) and torvoside H (3) yielded the corresponding acetal derivatives 4 and 5, respectively. Torvanol A (1), torvoside H (3) and compound 5 exhibited antiviral activity (herpes simplex virus type 1) with IC(50) values of 9.6, 23.2 and 17.4 microg/ml, respectively. Compounds 1-5 showed no cytotoxicity (at 50 microg/ml) against BC, KB and Vero cell lines.

Three known compounds, 2-hexylidene-3-methylsuccinic acid (1), cytochalasin Q (2), and 5-carboxymellein (3), together with two new derivatives, 2-hexylidene-3-methylsuccinic acid 4-methyl ester (4) and an ophiobolane sesterterpene named halorosellinic acid (5), were isolated from culture broth of the marine fungus Halorosellinia oceanica BCC 5149. Compounds 1-3 exhibited moderate cytotoxicity against KB and BC-1 cell lines with IC(50) values of 1-13 microg/mL, while compounds 2, 3, 5, and 6 showed antimalarial activity with respective IC(50) values of 17, 4, 13, and 19 microg/mL. Halorosellinic acid (5) possessed only weak antimycobacterial activity with the minimum inhibitory concentration of 200 microg/mL.

Racemosol and demethylracemosol, together with their possible biogenetic precursors, preracemosol A and preracemosol B, were isolated from the roots of Bauhinia malabarica Roxb. While only racemosol and demethylracemosol exhibited cytotoxicity against KB and BC cell lines, all four compounds exhibited moderate antimalarial activity.

Six bioactive naphthoquinone derivatives, erythrostominone, deoxyerythrostominone, 4-O-methyl erythrostominone, epierythrostominol, deoxyerythrostominol and 3,5,8-trihydroxy-6-methoxy-2-(5-oxohexa-1,3-dienyl)-1,4-naphthoquinone, were isolated from the insect pathogenic fungus Cordyceps unilateralis BCC1869. While the latter is synthetically known, both it and 4-O-methyl erythrostominone are products of fungus strain C. unilateralis BCC1869.

Fatty acid profile from crude extracts of local sea cucumber Stichopus chloronotus was determined using gas chromatography (GC) technique. The extracts were prepared separately in methanol, ethanol, phosphate buffer saline (PBS), and distilled water as part of our study to look at the affinity of these solvents in extracting the lipid from sea cucumber. The PBS and distilled water extractions indicate water-soluble components, while the organic fractions are extracted in methanol and ethanol as organic solvents. Furthermore, water extraction is the conventional method practiced in Malaysia. In our analysis the C14:0 (myristic), C16:0 (palmitic), C18:0 (stearic), C18:2 (linoleic), C20:0 (arachidic), and C20:5 (eicosapentaenoic, EPA) were significantly different (p < 0.01) in the four solvent extractions. However, the PBS extraction contained a much higher percentage of EPA (25.69%) compared to 18.89% in ethanol, 7.84% in distilled water, and only 5.83% in methanol, and variances were significantly different (p < 0.01). On the other hand, C22:6 (docosahexaenoic acid or DHA) is much higher in water extraction (57.55%), in comparison to the others where only 3.63% in PBS and 1.20 % in methanol, and this difference is significant at p < 0.01. No DHA was detected in ethanol extractions. Subsequently, C18:1 (oleic acid) was only detected in PBS (21.98%) and water extraction (7.50%). It is interesting that palmitic acid, C16:0 was higher in methanol (20.82%) and ethanol (20.18%), while 12.55% was detected in PBS and only 2.20% in water extraction; and again this was significantly different at p < 0.01. Although our results have shown that all four solvents were different in terms of their ability to extract fatty acids, the major component for tissue repair was well preserved. Probably this is one of the important precocious steps when working with a delicate sea cucumber, in both experimental and/or at the preparative stages. Freshness of the sea cucumber samples is important when undertaking this type of experiment. Finally, we believe that the local sea cucumber S. chloronotus contains all the fatty acids required to play a potential active role in tissue repair.

The effect of lecithin and cholesterol on growth and survival of larval and postlarval Penaeus monodon was evaluated using semi-purified diets containing four levels of lecithin (0.0, 0.5, 1.0 and 1.5%) and three levels of cholesterol (0.0, 0.5 and 1.0%). Three early stages (zoeal, mysid and postlarval) of P. monodon were fed the experimental diets. Growth and survival of shrimp fed diets containing 1.0 and 1.5% lecithin were not significantly different ( P >0.05) but these groups had significantly greater growth and survival than those fed 0.0 and 0.5% lecithin diets. Shrimp fed diets containing 1.0% cholesterol had significantly greater ( P P. monodon . During a low salinity stress test, PL-15 shrimp fed diets containing 1.0% cholesterol had significantly greater ( P

Biochemical conversions of ascorbate-2-monophosphate and ascorbate-2-sulfate to ascorbic acid by acid phosphatase and ascorbate-2-sulfate sulfohydrolase, respectively, were found in extracts of a hepatopancreas of Penaeus monodon, bovine liver and tilapia liver. Both enzymes were assayed with high-performance liquid chromatography (HPLC) and colorimetry. Colorimetry was based on the reduction of a color of 2,6-dichlorophenolindophenol (DCIP) when ascorbic acid was released from enzymatic activity. Assay of acid phosphatase either with HPLC or with colorimetry was found to be equally reliable. However, sensitivity of the HPLC assay was slightly higher than that of colorimetry; HPLC was able to detect activity as little as 1 nmol ascorbic acid released per min, whereas colorimetry was limited at 6–7 nmol/min. Assay of ascorbate-2-sulfate sulfohydrolase in crude extracts with the HPLC technique was found to be more specific than that with the colorimetric assay. The excess reduction of DCIP color not related to the sulfohydrolase activity was observed in the colorimetric technique. An accumulation of ascorbic acid in a hepatopancreas of P. monodon fed with feeds supplemented with phosphorylated or sulfated ascorbic acid was higher than that of the prawn fed with feed without ascorbic acid. The accumulated ascorbic acid was possibly from the activity of acid phosphatase or the sulfohydrolase that hydrolyzed phosphorylated or sulfated derivatives in vivo, respectively. Metabolism of the ascorbate derivatives in the prawn is discussed.

Two new pimarane diterpenes, diaportheins A (1) and B (2), were isolated from a culture broth of the fungus Diaporthe sp. BCC 6140. Diaporthein B (2) strongly inhibited the growth of Mycobacterium tuberculosis with the MIC value of 3.1 microg/mL, while diaporthein A (1) showed only mild activity (MIC value of 200 microg/mL).

l -[U- 14 C]Arginine, l -[U- 14 C]ornithine and [1,4- 14 C]putrescine were incorporated into anatoxin- a by Anabaena flos-aquae IC-1. To test the hypothesis that arginine and ornithine give rise to putrescine, which is oxidized to Δ 1 -pyrroline, and that this, in turn, is a precursor of anatoxin- a , cell-free extracts were incubated with [2,5- 14 C]Δ 1 -pyrroline. Subsequent chromatography demonstrated the disappearance of Δ 1 -pyrroline and production of a major radioactive metabolite identified as anatoxin- a . A strain of A. flos-aquae that had lost its ability to synthesize anatoxin- a also metabolized the 14 C-labelled Δ 1 -pyrroline but without yielding a major radioactive product. The arginine and ornithine decarboxylases required to produce putrescine, and a diamine oxidase to cyclize it to Δ 1 -pyrroline, were shown to be active in A. flos-aquae IC-1. The decarboxylases were associated with a particulate fraction sedimenting at 31 300 g . Assay of these enzymes by measuring CO 2 release gave rates up to 7 × those determined by amine production. With each of the two decarboxylases, chromatography on DEAE-cellulose gave two major peaks of CO 2 -releasing activity, only one of which coincided with amine-producing activity. Based on agmatine production, the K m for the arginine decarboxylase was 10 mM. The arginine and ornithine decarboxylases were both inhibited to a similar extent by difluoromethylarginine and difluoromethylornithine and it is suggested that this, together with their chromatographic coincidence, may indicate a single protein. The diamine oxidase was inhibited by endogenous low M r compounds, had a broad pH optimum of 8.5–9.5, and was not sedimented at 31 300 g . On fractional precipitation with (NH 4 ) 2 SO 4 , enzymic activity was found in the 60–80% saturation fraction. Chromatography of this fraction on DEAE-cellulose gave a single peak of activity which was not further resolved by gel-filtration chromatography on Sephadex G-200. A 55-fold purification of the oxidase was attained. It has a K m of 2.5 μM and an apparent M r of 21–22 ×10 3 . The toxin-producing and non-producing strains of A. flos-aquae showed similar rates of amine oxidase and ornithine decarboxylase activity. In a previously active anatoxin- a producing strain which has now lost this synthetic capacity, the 10 kb plasmid, described earlier, was replaced by a 6.5 kb plasmid.