Bis Ester Research Articles

Determination of Antioxidant Activity and Biochemical Content of Homalothecium philippeanum (Spruce) Schimp.

Living organisms produce reactive oxygen species (ROS) during the oxygen processing process. ROS damage biomolecules and causes oxidative stress. Antioxidants prevent cellular damage against these harmful effects of ROS by neutralizing free radicals. Medicinal plants provide a rich source of antioxidants to reduce oxidative stress and play an important role in the treatment of diseases. Bioactive compounds, especially polyphenols and flavonoids, protect cells against oxidative damage by neutralizing free radicals. Bryophytes, especially mosses, are one of the plant groups that attract attention in this area. Mosses show biologically active properties with secondary metabolites such as terpenes and flavonoids they contain. In this study, extraction of Homalothecium philippeanum moss with ethanol, methanol and n-hexane solvents was carried out and the biochemical content analysis of the extracts was investigated. 1,2-Benzenedicarboxylic acid, bis(2-methylpropyl) ester was detected as the major component in the ethanol and methanol extracts of the H. philippeanum. Biologically active alkanes such as Tetradecane and Hexadecane were found in the n-hexane extract. The antioxidant activity of moss ethanol extract was investigated using the DPPH method and the EC50 value was determined as 7.084 mg/ml.

Efficient separation of methyl ethyl ketone and water azeotrope using hydrophobic amino acid ester ionic liquids

BackgroundMethyl ethyl ketone (MEK), an essential organic solvent, is commonly produced via the n-butene method, where water emerges as the principal impurity. The conventional distillation processes, which are necessitated by the azeotropic behavior between MEK and water, result in a substantial expenditure of energy. As a result, liquid-liquid extraction represents a promising alternative for energy-efficient separation. MethodsIn this work, three hydrophobic amino acid ester ionic liquids L-phenylalanine ethyl ester bis(trifluoromethylsulfonyl) imide ([Phe][NTf2]), L-leucine ethyl ester bis(trifluoromethylsulfonyl) imide ([Leu][NTf2]) and L-valine ethyl ester bis(trifluoromethylsulfonyl) imide ([Val][NTf2]) were utilized as extractants for separation of the binary azeotrope methyl ethyl ketone and water. The effects of extraction time, extraction temperature, mass ratio of MEK-water mixture to ionic liquid and initial concentration of MEK on extraction efficiency were investigated. Significant findingsThe results demonstrate that the ionic liquid [Phe][NTf2] exhibits superior extraction ability for the separation of the azeotrope methyl ethyl ketone and water. The maximum extraction yield of 99.86 % was achieved with the optimum extraction conditions of extraction time, 10 min, extraction temperature, 293.15 K, mass ratio of mixture to ionic liquid, 1:1 and initial concentration of MEK, 20 %. In addition, the relationship between the structure of ionic liquids and their extraction performance was revealed by quantum chemical calculations of ionic liquids with MEK and water. These ionic liquids were positioned as promising environmentally friendly alternatives to traditional organic solvents for the recovery of MEK from aqueous solutions, providing valuable insights for industrial applications.

Comprehensive Analysis of Antioxidant Properties, GC-MS, and FTIR Profiles of Myrica esculenta Fruit Extracts from Western East Khasi Hills of Meghalaya.

This study investigates the phytoconstituents of Myrica esculenta fruit extracts using various solvents, including n-hexane, dichloromethane, ethyl acetate, methanol, and water. Qualitative phytochemical analysis revealed the presence of several phytochemicals, with the highest concentration found in the methanol extract. The total phenolic (94.5±0.96 mg gallic acid equivalent (GAE)/g) and flavonoid (74.27±0.29 mg quercetin equivalent (QE)/g) contents were also highest in the methanol extract. Antioxidant activity was measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTS), and Ferric Reducing Antioxidant Power (FRAP) assays. The methanol extract exhibited superior antioxidant activity with DPPH and ABTS IC50 values of 22.27±0.98 μg/ml and 19.69±0.36 μg/ml, respectively, compared to ascorbic acid. FRAP activity was also highest in the methanol extract (87.125±0.33 mg Trolox equivalents (TE)/g). Gas Chromatography-Mass Spectrometry (GC-MS) analysis identified antioxidant compounds hexanedioic acid, bis(2-ethylhexyl) ester, methyl 11,12-octadecadienoate, and pentadecanoic acid. while Fourier Transform Infrared Spectroscopy (FTIR) analysis detected functional groups such as alkenes, ketones, esters, alcohols and carboxylic acids. These findings suggest that the methanolic extract of M. esculenta fruits is a rich source of natural antioxidants, making it suitable for pharmaceutical, health, and nutritional supplements aimed at enhancing overall health.

A Green Chemo-Enzymatic Approach for CO2 Capture and Transformation into Bis(cyclic carbonate) Esters in Solvent-Free Media.

A sustainable approach for CO2 capture and chemo-enzymatic transformation into bis(cyclic carbonate) esters from CO2, glycidol, and organic anhydrides under solvent-free conditions has been demonstrated. The chemo-enzymatic process is based on two consecutive catalytic steps, which can be executed through separated operations or within a one-pot combo system, taking advantage of the synergic effects that emerge from integrating ionic liquid (IL) technologies and biocatalysts. In a first step, lipase-catalyzed transesterification and esterification reactions of different diacyl donors (e.g., glutaric anhydride, succinic anhydride, dimethyl succinate, etc.) with glycidol in solvent-free under mild reaction conditions (70 °C, 6 h) produce the corresponding diglycidyl ester derivatives in up to 41% yield. By a second step, the synthesis of bis(cyclic carbonate) esters was carried out as a result of the cycloaddition reaction of CO2 (from an exhausted gas source, 15% CO2 purity) on these diglycidyl esters, catalyzed by the covalently attached 1-decyl-2-methylimidazolium IL (supported ionic liquid-like phase, SILLP), in solvent-free condition, leading up to 65% yield after 8 h at 45 °C and 1 MPa CO2 pressure. Both key elements of the reaction system (biocatalyst and SILLP) were successfully recovered and reused for at least 5 operational cycles. Finally, different metrics have been applied to assess the greenness of the solvent-free chemo-enzymatic synthesis of bis(cyclic carbonate) esters here reported.

Antioxidant and Antibacterial Activities of Selected Medicinal Plants from Addis Ababa against MDR-Uropathogenic Bacteria.

This study determined the antioxidant and antibacterial activities of Thymus schimperi (Ts), Rhamnus prinoides (Rp), and Justicia schimperiana (Js) from Addis Ababa against MDR-Uropathogenic bacteria. Accordingly, Thymus schimperi had the highest total phenolic (TPC), flavonoid (TFC) and proanthocyanidin content. In Ts, the GC-MS analyses predicted 14 bioactive compounds. And among these, hexanedioic acid, bis(2-ethylhexyl) ester, thymol, and o-cymen-5-ol were the most predominant compounds, respectively. Six compounds were also predicted in Rp, where hexanedioic acid, bis(2-ethylhexyl) ester, β-D-glucopyranoside, methyl, and desulphosinigrin were the predominant, respectively. Whereas in the Js extract, five bioactive compounds were predicted, with hexanedioic acid, mono (2-ethylhexyl) ester, debrisoquine, and 8,11,14-heptadecatrienoate, methyl ester being predominant compounds, respectively. The extracts' TPC showed a strong negative correlation with the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay (r = -0.999; p = 0.023). In addition, the TFC correlated significantly with the ABTS (2,2'-azino-di-(3-ethylbenzthiazoline sulfonic acid)) assay (r = 0.999; p = 0.032). Thymus schimperi showed the highest antibacterial activity against clinical isolates of Escherichia coli and Klebsiella pneumoniae ESBL at 1000 mg/mL, and Ts had the lowest MIC (4 mg/mL) among evaluated extracts against E. coli (ATCC25922). In conclusion, Ts and Rp possess higher predicted bioactive molecules, including antioxidant and antibacterial activities, which are potentially useful in treating urinary tract infections.

The pro-drug C13 activates AMPK by two distinct mechanisms.

The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status that is expressed in almost all eukaryotic cells. In the canonical activation mechanism, it is activated by increases in AMP:ATP and ADP:ATP ratios that signify declining cellular energy status. Once activated, AMPK phosphorylates numerous targets that promote catabolic pathways generating ATP, while inhibiting anabolic and other processes that consume ATP, thus acting to restore energy homeostasis. Pharmacological agents that activate AMPK have been useful in identifying downstream targets and have potential as drugs for treatment of metabolic disorders such as Type 2 diabetes and non-alcoholic fatty liver disease. One such agent is C13, a pro-drug with a phosphonate bis(isobutyryloxymethyl) ester moiety, with the isobutyryloxymethyl groups increasing membrane permeability. Following cellular uptake, C13 is cleaved to release C2, an AMP analogue and potent AMPK activator that is specific for complexes containing the α1 (but not the α2) catalytic subunit isoform. This has previously been assumed to be the sole mechanism by which C13 activates AMPK, with potential roles for the isobutyryloxymethyl groups being ignored. We now report that, following cleavage from C13, these protective groups are metabolized to formaldehyde, an agent that inhibits mitochondrial function and increases cellular AMP:ATP ratios, thus providing additional AMPK activation by the canonical mechanism.

Neptunyl Pyrrophen Complexes: Exploring Schiff Base Chemistry with Multidentate Acyclic Ligands and Transuranics.

We report the synthesis, structure, and characterization of two novel neptunyl complexes (NpO2L1 and NpO2L2) constructed from phenylene-substituted benzyl ester bis(pyrrole)phenylenediamine (named "pyrrophen") ligands. In both cases, the neptunium center exists in the +6 oxidation state,. As our specific interest is in exploring the chemistry of neptunium compounds containing the linear neptunyl ion (NpO2 2+) through equatorially coordinating the metal by multidentate organic ligands, we have identified the differences that are likely to cause discrepancy between the two complexes by examining the ions and their coordinative environments through single-crystal X-ray crystallography, diffuse reflectance, and Raman spectroscopy. This is the first time pyrrophen has been utilized in Np chemistry and demonstrates a new platform to study 5 f electron participation and coordination.

FTIR and GC-MS analyses of raw materials produced from food wastes used in synthesis of biofilms

The present study carried out the GC-MS and FTIR analyses of raw materials (ripe plantain peel powder, cassava starch, glycerol, acetic acid (vinegar) and eggshell powder) produced from food wastes that are used in production of biofilm. The GC-MS results revealed the presence of pentadecane, bis (2-methylpropyl) ester and benzoic acid, 3-(2-Hydroxy-6-methylphenyl)-4(3H)-quinazolinone). The FTIR analysis revealed 17 peaks for glycerol, 16 peaks for vinegar, 15 peaks for cassava starch, 16 peaks for eggshell; representing the functional groups of ether, ethene, amine, carboxylic acid, nitriles, methylene cyclic ester, primary, secondary and tertiary alcohols common to hydrocarbons. The presence of carboxylic acid was important for enhancing the mechanical and chemical properties of biofilms thereby making them viable alternatives to petroleum-based plastics. Amines contributed to the flexibility, strength, and thermal degradation resistance of biofilms, thus aiding in their biodegradability. In conclusion, the study showed that the raw materials possessed biological activities and their functional groups indicated that the raw materials are safe to humans and the environment.

Developmental toxicity of an emerging organophosphate ester Bis-(2-ethylhexyl)-phenyl phosphate on embryonic zebrafish: Comparison to 2-ethylhexyl diphenyl phosphate

Bis-(2-ethylhexyl)-phenyl phosphate (BEHPP) and its structural analog, 2-ethylhexyl diphenyl phosphate (EHDPP), are widely present in the environment. However, their toxic effects, particularly developmental toxicity, remain poorly understood. In this study, we evaluated the impacts of BEHPP and EHDPP on multiple developmental endpoints in zebrafish. BEHPP did not lead to mortality and malformations of embryos within the test concentration range (0.5–4.0 μM). In contrast, EHDPP had significant lethal effects, with an LC50 of 2.44 μM, and induced malformations, notably pericardial edema (PE), with an EC50 of 1.77 μM. In addition, BEHPP induced cardiac dysfunctions in embryos to a similar degree as EHDPP. Both stroke volume and cardiac output were significantly increased at BEHPP concentrations of 1.8 nM and above and at EHDPP concentrations of 4.3 nM and above. Transcriptomic analysis further corroborated the similar disturbance at the molecular level for both substances and revealed the Key Events (KEs) in the cardiac toxic regulation, including the focal adhesions, ECM-receptor interaction, cardiac muscle contraction, and the adrenergic signaling in cardiomyocytes. Taken together, the present study provided novel insights into the adverse effects of these emerging organophosphate esters and highlighted their potential risks to embryonic development in both ecosystems and humans.

Arthrobotrys oligospora (Fungi: Orbiliales) and its liquid culture filtrate myco-constituents kill Haemonchus contortus infective larvae (Nematoda: trichostrongylidae)

ABSTRACT Arthrobotrys oligospora is a nematode-trapping fungus belonging to the family Orbiliaceae and one of the main antagonists of nematodes in soil, including plant and animal parasitic nematodes and free-living nematodes. This species develops three-dimensional adhesive nets in which nematodes are trapped, destroyed and consumed by the fungus. It also possesses other strategies to immobilise, kill and degrade nematodes, i.e. nematode-attractant substances, cuticle adhesion polymers and a number of nematocidal metabolites. The objective of this study was to assess the in vitro nematocidal activity of a strain of A. oligospora through its predatory activity and its liquid culture filtrates (LCF) against the ruminant parasite Haemonchus contortus (HcL3) and to investigate the presence of myco-compounds with potential nematocidal activity. Predatory activity (PA) was assessed in agar plates; 200 HcL3 were placed on agar plates with the fungus and a control group and incubated for 10 days. The LCF confrontation with nematodes was performed in microtiter plates. Two media, Czapek-Dox Broth (Cz-DB) and potato dextrose broth, were assessed. Three concentrations (25, 50 and 100 mg/mL) were assessed at 48 and 72 h (n = 4, per concentration). The experiment was performed in triplicate. The results showed 73.6 ± 2.7% PA and the highest mortality (83%) with the LCF in Cz-DB after 72 h. Gas chromatography–mass spectrometry (GC–MS) analysis revealed that the A. oligospora ethyl acetate phase was composed of 1,2-benzenedicarboxylic acid, bis (2-methylpropyl) ester, (M) 1,4-benzenedicarboxylic acid, bis (2-methylpropyl) ester and (M) decanedioic acid (2-ethylexyl) ester. These compounds could be responsible for nematocidal activity.

Phytochemical, proximate analysis and antioxidant activity of the rhizome of Alpinia nigra (Gaertn.) B.L. Burtt (Zingiberaceae) in Tamulpur district, Assam

The present research examines the chemical composition, proximate characteristics and antioxidant analysis of Alpinia nigra’s rhizome extract. Results of GC-MS analysis revealed a total of 22 volatile compounds of which Tris (tert-butyldimethylsilyloxy) arsane (2.89 %), 2-ethylthiolane, S, S-dioxide (3.47 %), Ambrial (6.68 %) and Silicic acid, diethyl bis (trimethylsilyl) ester (4.59 %) were the major compounds. The rhizome was found to have variable quantities of proximate compositions such as moisture content (55.5 %), ash content (4.72 %), crude fat (52 %), crude fibre (41.25 %), crude protein (28.95 µg/g), carbohydrate (46.27 %) and dry matter (33.4 %). The crude extraction of the rhizome was done by Soxhlet apparatus. The phytochemical screening showed the presence of alkaloid, tannin, terpenoid, glycoside, steroid, carbohydrate and a considerable amount of phenol and flavonoid. Phenolic and flavonoid content in the extracts was determined by the Folin-Ciocalteu and aluminium chloride assays as gallic acid equivalent and quercetin equivalent respectively. To evaluate the antioxidant activity of rhizome extract, phosphomolybdenum assay, ferric-reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picryl-hydrazil (DPPH) were used. The findings indicate that the rhizome extract is rich in phenol and flavonoid content and would serve as a promising source of natural antioxidants in the food, cosmetics and pharmaceutical industries.

Chemical Composition and Antioxidants of Senecio vulgaris (Asteraceae)

The study included the antioxidant and chemical compounds of methanolic extract of Senecio vulgaris in Iraq. S. vulgaris has a rich history in traditional medicine for treating different health problems. The results gas chromatography-mass spectrometry (GC-MS) chromatogram of S. vulgaris extract showed 19 peaks, which indicates the presence of 19 compounds (phytochemical constituents). Most of the chemical components extracted from S. vulgaris include oleic acid (40.46%), n-Hexadecanoic acid (23.40%), 5,9-dimethyl-2-(1-methylethyl)-1-cyclodecanone (6.52%), octadecanoic acid (3.57%) and 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester (3.27%). The antioxidant activity of overall methanol extract contents of S. vulgaris was determined by adding different concentrations of methanol extract to 2,2-diphenyl-1-picrylhydrazyle (DPPH). The inhibitory activity was evaluated by using five different concentrations of methanol extract of S. vulgaris. The results showed that the antioxidant activity in concentration 3 μL/mL was 41.23%, while the highest antioxidant activity was 98.33% in 25 μL/mL compared with vitamin C, which was 16% in 3 μL/mL and recorded 91.97% in 25 μL/mL. The total antioxidant capacity of S. vulgaris methanol extract was evaluated as vitamin C equivalents per gram. The DPPH radical scavenging potency with a minimum IC50 value in S. vulgaris was 5.64 μL/mL, while vitamin C was 3.09.

Comprehensive analysis of phytochemical profiling, cytotoxic and antioxidant potentials, and identification of bioactive constituents in methanoic extracts of Sonneratia apetala fruit

In the delta region of Bangladesh, Sonneratia apetala, also known as Keora and mangrove apple, is widely recognized for its dual role as a source of both food and medicine. Seasonal S. apetala fruits were gathered from Hatiya, Noakhali, in October 2021. The samples were segregated into pericarps and seeds, then fractionated into methanol segments. The anti-proliferative activities of these samples against lung A549 cells were evaluated using the Trypan blue exclusion method. Additionally, High-Performance Liquid Chromatography (HPLC) was employed to quantify phenolic compounds, while standard protocols facilitated the identification of specific phytochemical constituents. Chemical profiling via Gas Chromatography-Mass Spectrometry (GC-MS) and the isolation and detection of bioactive compounds through column chromatography and Nuclear Magnetic Resonance (NMR) analysis were undertaken. The methanol fractions of the seeds and pericarp were found to contain carbohydrates, tannins, flavonoids, steroids, alkaloids, glycosides, and terpenoids, with the absence of saponins and anthraquinones. Notably, the anti-proliferative effect demonstrated statistical significance at a concentration of 300 μg/mL for both extracts. Furthermore, HPLC analysis identified and quantified six polyphenols: catechin hydrate, (−)-epicatechin, rutin hydrate, trans-ferulic acid, trans-cinnamic acid, myricetin, and kaempferol, with the following concentrations: 46.65 and 12.72; 349.29 and 140.39; 5.26 and 33.06; 10.35 and 29.28; ND and 11.93; and 10.03 and 7.90 mg/100 g in the methanol fraction of the seed and pericarp, respectively. GC-MS analysis of S. apetala fruit revealed five notable compounds with significant peak areas (%): 2-methyltetracosane, tetratetracontane, heptacosane, 1-chloro-2-hexyl-1-octanol, and phenol, 3,5-bis(1,1-dimethylethyl), exhibiting peak areas of 43.96, 35.8, and 15.95, respectively. Meanwhile, the notable peak in S. apetala seeds was 1,3-benzenedicarboxylic acid, bis(2-ethylhexyl) ester, with a peak area (%) of 100. These compounds are known for their anticancer and antioxidant properties. Therefore, S. apetala, particularly its seeds and fruits, shows promising potential for development into dietary supplements and functional foods.

Crystal structure elucidation of a geminal and vicinal bis(trifluoromethanesulfonate) ester.

Geminal and vicinal bis(trifluoromethanesulfonate) esters are highly reactive alkylene synthons used as potent electrophiles in the macrocyclization of imidazoles and the transformation of bypyridines to diquat derivatives via nucleophilic substitution reactions. Herein we report the crystal structures of methylene (C3H2F6O6S2) and ethylene bis(trifluoromethanesulfonate) (C4H4F6O6S2), the first examples of a geminal and vicinal bis(trifluoromethanesulfonate) ester characterized by single-crystal X-ray diffraction (SC-XRD). With melting points slightly below ambient temperature, both reported bis(trifluoromethanesulfonate)s are air- and moisture-sensitive oils and were crystallized at 277 K to afford two-component non-merohedrally twinned crystals. The dominant interactions present in both compounds are non-classical C-H...O hydrogen bonds and intermolecular C-F...F-C interactions between trifluoromethyl groups. Molecular electrostatic potential (MEP) calculations by DFT-D3 helped to quantify the polarity between O...H and F...F contacts to rationalize the self-sorting of both bis(trifluoromethanesulfonate) esters in polar (non-fluorous) and non-polar (fluorous) domains within the crystal structure.

Chemical Profiling of Essential Oil Extracted from Fresh Walang Leaves (Etlingera walang (Blume) R. M. Sm.), an Indigenous Species in Banten, Indonesia

Essential oils are a group of secondary metabolite compounds that have a distinctive aroma and are volatile. Walang leaves are one of the plants suspected of having essential oil content. This study aims to determine the constituent components of essential oil compounds from fresh walang leaves. The method used to extract essential oil from fresh walang leaves is steam distillation. The essential oil produced was analyzed using Gas Chromatography Mass Spectroscopy (GC-MS). The results showed that the essential oil of fresh walang leaves contained 15 components of essential oil compounds and 2 main components of essential oil compounds, namely: Acetic acid (CAS) Ethylic acid 24.52%, 1,2 Benzenedicarboxylic acid, bis(2-methylpropyl) ester (CAS) Isobutyl phthalate 21.09%.

In vitro antioxidant and anticancer potential of intra-cellular ethyl acetate extract of marine-derived fungus Talaromyces tratensis SS10

Marine fungi are well-known for producing structurally distinct secondary metabolites, making them potential sources of novel therapies. The present investigation aims to study the in vitro antioxidant and anticancer potential of intra-cellular crude ethyl acetate extracts of Talaromyces tratensis SS10. In the present study, qualitative and quantitative phytochemical studies of various solvent extracts of T. tratensis have been carried out using standard protocols. Later, ethyl acetate extract of T. tratensis was analyzed for phytochemicals using Gas Chromatography Mass Spectrometry (GC-MS). Further, the antioxidant properties of the T. tratensis ethyl acetate extract have been done by Ferric reducing antioxidant power assay (FRAP). Further, the anticancer potential of this extract has been carried out by MTT assay against human cancer cells such as MDA MB 231, HeLa, and HT-29. Ethyl acetate exhibited a higher yield of chemical extraction than the other solvents used. The GCMS analysis of T. tratensis ethyl acetate extract revealed major phytoconstituents such as N-(1,1-Dimethylpropyl)-2,2,3-trimethylaziridine-1-carboxamide, 1-Undecanol, 5,5 Dimethyl-3-vinyl cyclohex-2-en-1-one, 1,2-Benzenedicarboxylic acid, bis (2-methyl propyl) ester. T. tratensis ethyl acetate extract showed the highest percentage of Fe3+ reduction (48.093±1.469%) at 120 μg/mL, with an IC50 value of 157.26 μg/mL concentration. Furthermore, 100 μg/mL of the extract showed significant cell death rates in cytotoxic assays, indicating a low percentage of viable cells for all three examined cell lines. The T. tratensis ethyl acetate extract has shown a dose-dependent cytotoxic effect against all tested cancer cell lines. The better IC50 value (6.25 μg/mL) was recorded in the case of HeLa cell lines followed by 12.5 μg/mL for both MDA MB 231 and HT-29 cell lines. The presence of bioactive compounds such as Benzeneethanamine, N-[(pentafluorophenyl)methylene]-beta.,3,4-tris[(trimethylsilyl) oxy]-, 1,2-Benzenedicarboxylic acid, bis(2-methylpropyl) ester, and cyclononasiloxane, octadecamethyl- may have contributed to the ethyl acetate extracts’ strong antioxidant and anticancer properties. The current study’s findings show that T. tratensis SS10 has the potential for drug development due to its chemical constituents, which possess various biological activities.

Control of Microcystis aeruginosa by Daphnia: Experimental evidence and identification of involved infochemicals.

Infochemicals refer to chemicals responsible for information exchange between organisms. We evaluated the effects of Daphnia magna and Daphnia galeata infochemicals on Microcystis aeruginosa for 15d. The Daphnia infochemicals were obtained from spent medium after culturing Daphnia in Elendt M4 medium for 48 h. Both Daphnia infochemicals significantly increased (p < 0.05) the intracellular reactive oxygen species level and microcystin-LR concentration in M. aeruginosa. This cellular effect increased colony formation of M. aeruginosa, thereby inhibiting the growth of M. aeruginosa. D. galeata infochemicals provoked significantly greater (p < 0.05) adverse effects on M. aeruginosa than those of D. magna infochemicals, which were further exaggerated by pre-exposure of Daphnia to M. aeruginosa. This result seems to be related to the different compositions and concentrations of Daphnia infochemicals. Several Daphnia infochemicals, such as methyl ferulate, cyclohexanone, 3, 5-dimethyl, hexanedioic acid, and bis(2-ethylhexyl) ester, showed a high correlation with M. aeruginosa cell concentration (|r | >0.6), suggesting that they may play a key role in controlling harmful cyanobacteria. Additionally, pre-exposure of D. magna and D. galeata to M. aeruginosa produced oleic acid, methyl ester, and n-hexadecanoic acid, with a highly correlation with M. aeruginosa cell concentration (|r | >0.6). p-tolyl acetate and linoleic acid were detected only in the pre-exposed D. galeata infochemicals. These findings suggest that some of Daphnia infochemicals identified in this study can be a promising tool to control M. aeruginosa growth. However, further studies are required to verify the specific actions of these infochemicals against cyanobacteria.

A Novel Non-Psychoactive Fatty Acid from a Marine Snail, Conus inscriptus, Signals Cannabinoid Receptor 1 (CB1) to Accumulate Apoptotic C16:0 and C18:0 Ceramides in Teratocarcinoma Cell Line PA1.

The cannabinoid-type I (CB1) receptor functions as a double-edged sword to decide cell fate: apoptosis/survival. Elevated CB1 receptor expression is shown to cause acute ceramide accumulation to meet the energy requirements of fast-growing cancers. However, the flip side of continual CB1 activation is the initiation of a second ceramide peak that leads to cell death. In this study, we used ovarian cancer cells, PA1, which expressed CB1, which increased threefold when treated with a natural compound, bis(palmitoleic acid) ester of a glycerol (C2). This novel compound is isolated from a marine snail, Conus inscriptus, using hexane and the structural details are available in the public domain PubChem database (ID: 14275348). The compound induced two acute ceramide pools to cause G0/G1 arrest and killed cells by apoptosis. The compound increased intracellular ceramides (C:16 to 7 times and C:18 to 10 times), both of which are apoptotic inducers in response to CB1 signaling and thus the compound is a potent CB1 agonist. The compound is not genotoxic because it did not induce micronuclei formation in non-cancerous Chinese hamster ovarian (CHO) cells. Since the compound induced the cannabinoid pathway, we tested if there was a psychotropic effect in zebrafish models, however, it was evident that there were no observable neurobehavioral changes in the treatment groups. With the available data, we propose that this marine compound is safe to be used in non-cancerous cells as well as zebrafish. Thus, this anticancer compound is non-toxic and triggers the CB1 pathway without causing psychotropic effects.

Metabolite profiling of potential bioactive fractions from ethanol extract of Boehmeria nivea flowers by GC–MS/MS analysis

BackgroundRamie (Boehmeria nivea) has been reported to have a wide variety of secondary metabolite compounds in its vegetative organ that have distinct organic activities. Regarding the chemical composition of flowers, there have been no study considering their pharmacological effects. PurposeThis research aims to determine profile metabolites contained in B. nivea flowers employing a metabolomics approach. Study DesignThis research was designed to obtain a metabolite database from five dissolved fractions of ramie flower using a Gas Chromatography-Mass Spectrometry (GC–MS/MS) instrument. This study includes metabolite profiles from each fraction of the spectrum obtained, which are then investigated for potential bioactivity based on previously reported studies. Metabolite profiles were developed using Principal Component Analysis (PCA) to obtain information on clustering of the compounds and determination of marker compounds from each fraction analyzed. MethodsThe active compounds of the flowers were separated utilizing the maceration method with ethanol solvent and multilevel fractionation using n-hexane, dichloromethane, ethyl acetic acid derivation, butanol, and water employing a GC–MS/MS approach. Principal Component Analysis (PCA) was optimized with a total represented data diversity range of 60 % - 65 %. This allowed for the identification of characteristic compounds and similarities in compound substances accross the fractions. ResultGC–MS/MS interpretation showed the dominant compounds contained in each fraction of n-hexane, dichloromethane, n-butanol, ethyl acetate, and water are 9,12-Octadecadienoic acid, ethanol, 2-phenoxy-, butyl ester, and hexanedioic acid, bis(2-ethylhexyl) ester. PCA clustering showed combined similarity of the compound for ethyl acetate fraction with butanol, and also butanol with n-hexane. Meanwhile, the dichloromethane and water fractions have very small content similarities. The score plot indicated marker compounds of each fraction are: ethanol, 2-butoxy; hexane, 2,2,3-trimethyl-; phthalic acid, in (2-propylpentyl) ester; n-hexadecanoic acid, and Hexanedioic acid, bis(2- ethylhexyl) ester. ConclusionsThe abundance of compounds in the fractions shows potential for application as a source of new drug candidates. In addition, there are still many compounds that are unknown in structures or biological activities which could lead to further research to provide potential clues towards the bioprospecting of the plant. AbbreviationsCH2Cl2, dichloromethane; Dm1, Dimension 1; Dm2, Dimension 2; EtOAc, ethyl acetate; GC–MS/MS, Gas Chromatography–Mass Spectrometry; n-BuOH, n-butanol; PCA, Principal Component Analysis.

Aktivitas Antibakteri dan Antioksidan dari Senyawa Bioaktif Asal Bakteri Endofit Tanaman Nyatoh (Palaquium amboinense B.)

Nyatoh plant (Palaquium amboinense B.) is native to Indonesia which is known to have the ability to produce potential secondary metabolites. The aim of this study was to evaluate the antibacterial and antioxidant activities from bioactive compounds produced by endophytic bacteria from nyatoh leaves. Five endophytic bacteria were tested against 4 targeted bacteria including Escherichia coli ATCC 8739, Pseudomonas aeruginosa ATCC 15442, Bacillus subtilis ATCC 19659, and Staphylococcus aureus ATCC 6538. Bacterial isolate which had the strongest antibacterial activity was then fermented and extracted. The corresponding extract was further tested on disc diffusion method, determination of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values, antioxidant evaluation, and analyzed for its bioactive compound components via GC-MS analysis. The results showed that one isolate, namely D1 can produce secondary metabolite which act as antibacterial and antioxidant potentials. This corresponding extract has the strongest MIC and MBC against B. subtilis with value of 39.5 and &gt;78.1 µg/ml and exhibited antioxidant activity against 2,2-difenil-1-pikrilhidrazil (DPPH) with inhibition value of 85.37%. Based on GC-MS analysis, secondary metabolites derived from this potential extract contained some major active constituents including Tributyl acetylcitrate and bis (2-ethylhexyl) ester which might act as antibacterial and antioxidant agents.