Natural Abundance 14C Content of Dibutyl Phthalate (DBP) from Three Marine Algae

Microbial dynamics, chemical profile, and bioactive potential of diverse Egyptian marine environments from archaeological wood to soda lake

Halophilic archaea are a unique group of microorganisms that thrive in high-salt environments, exhibiting remarkable adaptations to survive extreme conditions. Archaeological wood and El-Hamra Lake serve as a substrate for a diverse range of microorganisms, including archaea, although the exact role of archaea in archaeological wood biodeterioration remains unclear. The morphological and chemical characterizations of archaeological wood were evaluated using FTIR, SEM, and EDX. The degradation of polysaccharides was identified in Fourier transform infrared analysis (FTIR). The degradation of wood was observed through scanning electron microscopy (SEM). The energy dispersive X-ray spectroscopy (EDX) revealed the inclusion of minerals, such as calcium, silicon, iron, and sulfur, into archaeological wood structure during burial and subsequent interaction with the surrounding environment. Archaea may also be associated with detected silica in archaeological wood since several organosilicon compounds have been found in the crude extracts of archaeal cells. Archaeal species were isolated from water and sediment samples from various sites in El-Hamra Lake and identified as Natronococcus sp. strain WNHS2, Natrialba hulunbeirensisstrain WNHS14, Natrialba chahannaoensis strain WNHS9, and Natronococcus occultus strain WNHS5. Additionally, three archaeal isolates were obtained from archaeological wood samples and identified as Natrialba chahannaoensisstrain W15, Natrialba chahannaoensisstrain W22, and Natrialba chahannaoensisstrain W24. These archaeal isolates exhibited haloalkaliphilic characteristics since they could thrive in environments with high salinity and alkalinity. Crude extracts of archaeal cells were analyzed for the organic compounds using gas chromatography-mass spectrometry (GC-MS). A total of 59 compounds were identified, including free saturated and unsaturated fatty acids, saturated fatty acid esters, ethyl and methyl esters of unsaturated fatty acids, glycerides, phthalic acid esters, organosiloxane, terpene, alkane, alcohol, ketone, aldehyde, ester, ether, and aromatic compounds. Several organic compounds exhibited promising biological activities. FTIR spectroscopy revealed the presence of various functional groups, such as hydroxyl, carboxylate, siloxane, trimethylsilyl, and long acyl chains in the archaeal extracts. Furthermore, the archaeal extracts exhibited antioxidant effects. This study demonstrates the potential of archaeal extracts as a valuable source of bioactive compounds with pharmaceutical and biomedical applications.

Chemical composition of organic extracts of Phyla nodiflora L. in Syria by GC-MS

Introduction

Phyla nodiflora L. is a perennial herbaceous plant belonging to the Verbenaceae family. It is widely used as an herbal drink to treat many diseases. It has antioxidant, antifungal and anti-inflammatory properties. In traditional medicine, it is used to treat skin infections. However, there is little information on the chemical composition of organic plant extracts. Therefore, the aim of this study was to determine the chemical composition of organic extracts of P. nodiflora L.

Methods

In this study, organic extracts were prepared using a continuous Soxhlet extractor and four different solvents with increasing polarity from nonpolar to polar solvents (petroleum ether, chloroform, ethyl acetate, and isopropanol) to ensure the possibility of extracting a wide range of compounds. GC‒MS analysis was performed to determine the chemical constituents of the organic extracts.

Results

Nineteen compounds were identified in the petroleum ether (Et) extract, 14 in the chloroform (Ch) extract, 18 in the ethyl acetate (Ea) extract and 15 in the isopropanol (Is) extract. The most important compounds in the Et extract were 1,1-diethoxyethane (33.9 %) and nonadecane (19.9 %). The most important compound in the Ch extract was octacosane (37.4 %). The most important compounds in the Ea extract were 3-hydroxy-dodecanoic acid (17.7 %) and geranyl isovalerate (15.5 %). The most important compound in the Is extract was behenic acid alcohol (18.6 %). The chemical structures of the major compounds were confirmed by mass spectrometry by studying their fragmentation mechanism and comparing the molecular weights of the resulting fragments with the molecular weights of the peaks present in each mass spectrum.

Conclusions

The results of this study show that the dominant compounds in nonpolar extracts (petroleum ether and chloroform) are hydrocarbons, ethers, epoxides, and silicon compounds, while the dominant compounds in moderately polar extracts (ethyl acetate and isopropanol) are alcohols, carbonyl compounds, and oxygenated terpenes.

Pigmentiphaga kullae CHJ604 improved the growth of tobacco by degrading allelochemicals and xenobiotics in continuous cropping obstacles

Plant autotoxicity is considered to be one of the important causes of continuous cropping obstacles in modern agriculture, which accumulates a lot of allelochemicals and xenobiotics and is difficult to solve effectively. To overcome tobacco continuous obstacles, a strain Pigmentiphaga kullae CHJ604 isolated from the environment can effectively degrade these compounds in this study. CHJ604 strain can degrade 11 types of autotoxicity allelochemicals and xenobiotics (1646.22 μg/kg) accumulated in the soil of ten-years continuous cropping of tobacco. The 11 allelochemicals and xenobiotics significantly reduced Germination Percentage (GP), Germination Index (GI), and Mean Germination Time (MGT) of tobacco seeds, and inhibited the development of leaves, stems, and roots. These negative disturbances can be eliminated by CHJ604 strain. The degradation pathways of 11 allelochemicals and xenobiotics were obtained by whole genome sequence and annotation of CHJ604 strain. The heterologous expression of a terephthalate 1,2-dioxygenase can catalyze 4-hydroxybenzoic acid, 4-hydroxy-3-methoxybenzoic acid, 4-hydroxybenzaldehyde, and 4-hydroxy-3-methoxy-benzaldehyde, respectively. The phthalate 4,5-dioxygenase can catalyze phthalic acid, diisobutyl phthalate, and dibutyl phthalate. These two enzymes are conducive to the simultaneous degradation of multiple allelochemicals and xenobiotics by strain CHJ604. This study provides new insights into the biodegradation of autotoxicity allelochemicals and xenobiotics as it is the first to describe a degrading bacterium of 11 types of allelochemicals and xenobiotics and their great potential in improving tobacco continuous obstacles.

Assessment of stable carbon isotope 13С/12С ratio in phthalates from surface waters using HPLC-HRMS-TOF approach

A method for estimating the ratio of stable carbon isotopes 13С/12С in the composition of phthalates from surface water at a trace concentration level is proposed. It is based on the concentration of hydrophobic components of water using an analytical reversed phase HPLC column followed by their gradient separation and detection of eluted phthalates using a high-resolution time-of-flight mass spectrometer (ESI-HRMS-TOF) in the form of molecular ions. The ratio of stable carbon isotopes 13С/12C in phthalates is calculated as a ratio of integrals under the monoisotopic [M+1+H]+ and [M+H]+ peaks. The Δ13C value is calculated relatively to the 13C/12C ratio in commercial DnBP and DEHP phthalates used as standards. The minimal concentration of DnBP and DEHP in water required for a reliable determination of Δ13C value is estimated by the level of ca. 0.2 μg L-1. The technique has been verified during the monitoring of priority phthalates in the waters of Lake Baikal.

Comparative metabolomic analysis of exudates of microcystin-producing and microcystin-free Microcystis aeruginosa strains

Cyanobacterial harmful algal blooms (cHABs) dominated by Microcystis aeruginosa threaten the ecological integrity and beneficial uses of lakes globally. In addition to producing hepatotoxic microcystins (MC), M. aeruginosa exudates (MaE) contain various compounds with demonstrated toxicity to aquatic biota. Previously, we found that the ecotoxicity of MaE differed between MC-producing and MC-free strains at exponential (E-phase) and stationary (S-phase) growth phases. However, the components in these exudates and their specific harmful effects were unclear. In this study, we performed untargeted metabolomics based on liquid chromatography-mass spectrometry to reveal the constituents in MaE of a MC-producing and a MC-free strain at both E-phase and S-phase. A total of 409 metabolites were identified and quantified based on their relative abundance. These compounds included lipids, organoheterocyclic compounds, organic acid, benzenoids and organic oxygen compounds. Multivariate analysis revealed that strains and growth phases significantly influenced the metabolite profile. The MC-producing strain had greater total metabolites abundance than the MC-free strain at S-phase, whereas the MC-free strain released higher concentrations of benzenoids, lipids, organic oxygen, organic nitrogen and organoheterocyclic compounds than the MC-producing strain at E-phase. Total metabolites had higher abundance in S-phase than in E- phase in both strains. Analysis of differential metabolites (DMs) and pathways suggest that lipids metabolism and biosynthesis of secondary metabolites were more tightly coupled to growth phases than to strains. Abundance of some toxic lipids and benzenoids DMs were significantly higher in the MC-free strain than the MC-producing one. This study builds on the understanding of MaE chemicals and their biotoxicity, and adds to evidence that non-MC-producing strains of cyanobacteria may also pose a threat to ecosystem health.

First Data on PAE Levels in Surface Water in Lakes of the Eastern Coast of Baikal

The increasing consumption of phthalates (PAEs), along with their high toxicity and high mobility, poses a threat to the environment. This study presents initial data on the contents of six priority PAEs in the water of lakes located on the eastern shore of Lake Baikal-Arangatui, Bormashevoe, Dukhovoe, Kotokel, and Shchuchye. The mean total concentrations of the six PAEs in lakes Arangatui and Bormashevoe (low anthropogenic load) were comparable to those in Kotokel (medium anthropogenic load, 17.34 µg/L) but were significantly higher (p < 0.05) than in Dukhovoe and Shchuchye (high anthropogenic load, 10.49 and 2.30 µg/L, respectively). DBP and DEHP were the main PAEs in all samples. The DEHP content in lakes Arangatui and Bormashevoe was quite high, and at some sampling sites it exceeded the MACs established by Russian, U.S. EPA, and WHO regulations. The assessment showed that there is no potential risk to humans associated with the presence of PAEs in drinking water. However, the levels of DEHP, DBP, and DnOP in the water pose a potential threat to sensitive aquatic organisms, as shown by the calculated risk quotients (RQs). It is assumed that the origin of the phthalates in the studied lakes is both anthropogenic and biogenic.

Crosstalk between biological and chemical diversity with cytotoxic and cytostatic effects of Aphanothece halophytica in vitro

Different solvent extracts from Aphanothece halophytica (A. halophytica) were evaluated for their cytotoxic effects against four human cancer cell lines. The samples demonstrated different percentages of cyanobacteria species populations. The samples containing 100% A. halophytica and 90% A. halophytica showed a significant cytotoxic effect in human breast cancer cells MDA231. The cytostatic effect was demonstrated in MDA231 and human glioblastoma T98G cells regardless of the treatment, resulting in a significant cell cycle arrest in the S phase. The chemical profiles of the extracts were proven to be diverse in qualitative and quantitative compositions. This variability was dependent on the A. halophytica´s abundance in each extract. The 100% A. halophytica extract induced cytotoxic and cytostatic effects in breast cancer cells, and those could be associated with the predominance of fatty acids, hydrocarbons and phthalates, indicating that A. halophytica is an interesting source of novel compound with anticancer effect.

In Vitro Antibacterial and Antioxidant Activities and Molecular Docking Analysis of Phytochemicals from Cadia purpurea Roots

Phytochemicals and antibacterial and antioxidant activities of Cadia purpurea roots were investigated herein for the first time. The phytochemical study led to the isolation of two compounds, di-(2-methylheptyl) phthalate (1) and 13-O-pyrrolecarboxyl lupanine (2), from methanol roots extract of C. purpurea. The antibacterial activity results revealed that the n-hexane extract presented a better inhibitory value (13.8 ± 0.0 mm) followed by chloroform (11.1 ± 0.4 mm) and chloroform : methanol (1 : 1) (10.7 ± 0.1 mm) extracts against E. coli at the maximum dose of 100 mg/mL. While, methanolic and ethanolic extracts displayed a mild activity against same bacterium at same dose. The methicillin resistant S. aureus was found with almost total resistance to all extracts up to the 100 mg/mL. The chloroform : methanol (1 : 1), chloroform, and n-hexane extracts recorded inhibition zone values (8.0 ± 0.0–10.0 ± 0.1 mm, 7.7 ± 0.0–9.8 ± 0.1 mm, and 7.3 ± 0.2–8.9 ± 0.2 mm, respectively) better than chloramphenicol (7.2 ± 0.6 mm at 30 μg dose) against P. aeruginosa. The alcoholic extracts also exhibited an activity better than chloramphenicol up to 25 mg/mL against same bacterium. Compound 2 produced a comparable inhibition value (9.6 ± 0.0 mm to 18.5 ± 0.0 mm) to that of chloramphenicol (21.5 ± 0.3 mm) against E. coli at doses up to 1.0 mg/mL; whereas, compound 1 showed a slight activity (7.1 ± 0.1 mm–10.3 ± 0.0 mm). Both compounds were found generally inactive against S. aureus, while they provided an activity better than chloramphenicol (7.2 ± 0.6 mm) against P. aeruginosa with inhibition zones ranging from 7.1 ± 0.0 mm to 9.0 ± 0.1 mm for compound 1 and 7.2 ± 0.0 mm to 10.6 ± 0.0 mm for compound 2. Ethanolic and methanolic extracts exhibited a better DPPH radical scavenging activity (IC50 values of 12.9 and 16.03 μg/mL, respectively) and strong ferric ion reducing power (with absorbance of 0.788 ± 0.000 and 0.810 ± 0.001, respectively) at a concentration of 500 μg/mL compared to the other extracts. Compound 1 also possessed a better anti-DPPH trapping activity (IC50, 7.99 μg/mL) than compound 2 (IC50, 58.34 μg/mL). The compounds, however, indicated a weak ferric ion reduction power even at higher amount. In general, the observed antibacterial and antioxidant activities of isolated compounds and extracts were found to be dose-dependent. Conducting further biochemical investigations on all parts of this plant could provide opportunities of finding extra alkaloidal compounds and other phthalate derivatives with better biological activity.

Phthalic Acid Esters: Natural Sources and Biological Activities

Phthalic acid esters (PAEs) are a class of lipophilic chemicals widely used as plasticizers and additives to improve various products' mechanical extensibility and flexibility. At present, synthesized PAEs, which are considered to cause potential hazards to ecosystem functioning and public health, have been easily detected in the atmosphere, water, soil, and sediments; PAEs are also frequently discovered in plant and microorganism sources, suggesting the possibility that they might be biosynthesized in nature. In this review, we summarize that PAEs have not only been identified in the organic solvent extracts, root exudates, and essential oils of a large number of different plant species, but also isolated and purified from various algae, bacteria, and fungi. Dominant PAEs identified from natural sources generally include di-n-butyl phthalate, diethyl phthalate, dimethyl phthalate, di(2-ethylhexyl) phthalate, diisobutyl phthalate, diisooctyl phthalate, etc. Further studies reveal that PAEs can be biosynthesized by at least several algae. PAEs are reported to possess allelopathic, antimicrobial, insecticidal, and other biological activities, which might enhance the competitiveness of plants, algae, and microorganisms to better accommodate biotic and abiotic stress. These findings suggest that PAEs should not be treated solely as a "human-made pollutant" simply because they have been extensively synthesized and utilized; on the other hand, synthesized PAEs entering the ecosystem might disrupt the metabolic process of certain plant, algal, and microbial communities. Therefore, further studies are required to elucidate the relevant mechanisms and ecological consequences.

Beneficial Effects of Cyclic Ether 2-Butoxytetrahydrofuran from Sea Cucumber Holothuria scabra against Aβ Aggregate Toxicity in Transgenic Caenorhabditis elegans and Potential Chemical Interaction

The pathological finding of amyloid-β (Aβ) aggregates is thought to be a leading cause of untreated Alzheimer’s disease (AD). In this study, we isolated 2-butoxytetrahydrofuran (2-BTHF), a small cyclic ether, from Holothuria scabra and demonstrated its therapeutic potential against AD through the attenuation of Aβ aggregation in a transgenic Caenorhabditis elegans model. Our results revealed that amongst the five H. scabra isolated compounds, 2-BTHF was shown to be the most effective in suppressing worm paralysis caused by Aβ toxicity and in expressing strong neuroprotection in CL4176 and CL2355 strains, respectively. An immunoblot analysis showed that CL4176 and CL2006 treated with 2-BTHF showed no effect on the level of Aβ monomers but significantly reduced the toxic oligomeric form and the amount of 1,4-bis(3-carboxy-hydroxy-phenylethenyl)-benzene (X-34)-positive fibril deposits. This concurrently occurred with a reduction of reactive oxygen species (ROS) in the treated CL4176 worms. Mechanistically, heat shock factor 1 (HSF-1) (at residues histidine 63 (HIS63) and glutamine 72 (GLN72)) was shown to be 2-BTHF’s potential target that might contribute to an increased expression of autophagy-related genes required for the breakdown of the Aβ aggregate, thus attenuating its toxicity. In conclusion, 2-BTHF from H. scabra could protect C. elegans from Aβ toxicity by suppressing its aggregation via an HSF-1-regulated autophagic pathway and has been implicated as a potential drug for AD.

Isolation and Structure Elucidation of a Novel Symmetrical Macrocyclic Phthalate Hexaester

A novel symmetrical macrocyclic phthalate hexaester (1) and a known macrocyclic phthalate tetraester (2) were isolated during a natural product-exploring program on the cyanobacterium Moorea producens. Their structures were elucidated based on spectroscopic data, including nuclear magnetic resonance and high-resolution mass spectra. In the antibacterial activity test, compounds 1 and 2 showed no bioactivity at the concentrations tested.

Bioactive natural derivatives of phthalate ester

The advantages and emergent interest in organism-derived bioactive molecules have recently renewed scientific research attention in this field. Since 1967, about 52 different derivatives of phthalate ester (PE) have been reported from different taxonomic groups. Anthropogenic derivatives of the PEs are confined to petroleum products, as a plasticizer. These derivatives exhibit a potential toxicity on the living system, particularly those having a reduced molecular weight. An organism-derived PE differs chemically from that of synthetic ones in terms of the abundance of ¹⁴C and its bond structure, leading to its varied activities in the biological system. The study of the biosynthetic pathway and the optimization of parameters for product enhancement have advocated their organism-derived nature. Various bioactivities of such organisms-derived derivatives of phthalates such as antibacterial, antifungal, an inducer of apoptosis and cell cycle arrest, antioxidant, cytotoxic, antitumor, allopathic, larvicidal, antifouling, chemotactic, antimelanogenic, antiviral, and anti-inflammatory activities have been well documented. This is the first review that focuses on the positive bioactivities of such organism-derived PEs in detail. There is enormous scope for research in this field to search for the utilization of such organism-derived phthalate derivatives will have potential bioactivity, their possible use to improve their efficacy.

Toxicological effects of marine seaweeds: a cautious insight for human consumption

Marine environment is a rich and diverse source for many biologically active substances including functional foods and nutraceuticals. It is well exploited for useful compounds, natural products and aquaculture industry; and seaweeds is one of the major contributors in terms of both food security and healthy nutrition. They are well-known due to their enormous benefits and is consumed globally in many countries. However, there is lack of attention toward their toxicity reports which might be due toxic chemical compounds from seaweed, epiphytic bacteria or harmful algal bloom and absorbed heavy metals from seawater. The excess of these components might lead to harmful interactions with drugs and hormone levels in the human body. Due to their global consumption and to meet increasing demands, it is necessary to address their hazardous and toxic aspects. In this review, we have done extensive literature for healthy seaweeds, their nutritional composition while summarizing the toxic effects of selected seaweeds from red, brown and green group which includes- Gracilaria, Acanthophora, Caulerpa, Cladosiphon, and Laminaria sp. Spirulina, a microalgae (cyanobacteria) biomass is also included in toxicity discussion as it an important food supplement and many times shows adverse reactions and drug interactions. The identified compounds from seaweeds were concluded to be toxic to humans, though they exhibited certain beneficial effects too. They have an easy access in food chain and thus invade the higher trophic level organisms. This review will create an awareness among scientific and nonscientific community, as well as government organization to regulate edible seaweed consumption and keep them under surveillance for their beneficial and safe consumption.

A Fluorescent Compound from the Exuviae of the Scorpion, Liocheles australasiae

Most scorpions fluoresce under UV light. To date, two types of fluorescent compounds have been identified in scorpions, but it has been assumed that other unknown compounds may be responsible for the fluorescence. In this study, we isolated a fluorescent compound from the exuviae of the scorpion Liocheles australasiae identified as a macrocyclic diphthalate ester with a molecular mass of 496.2 Da. The same compound was also detected in extracts from four other scorpion species. This suggests that this compound is shared by multiple scorpion species, although its contribution to the cuticle fluorescence may be relatively small.

Chemical Diversity of Codium bursa (Olivi) C. Agardh Headspace Compounds, Volatiles, Fatty Acids and Insight into Its Antifungal Activity

The focus of present study is on Codium bursa collected from the Adriatic Sea. C. bursa volatiles were identified by gas chromatography and mass spectrometry (GC-FID; GC-MS) after headspace solid-phase microextraction (HS-SPME), hydrodistillation (HD), and supercritical CO₂ extraction (SC-CO₂). The headspace composition of dried (HS-D) and fresh (HS-F) C. bursa was remarkably different. Dimethyl sulfide, the major HS-F compound was present in HS-D only as a minor constituent and heptadecane percentage was raised in HS-D. The distillate of fresh C. bursa contained heptadecane and docosane among the major compounds. After air-drying, a significantly different composition of the volatile oil was obtained with (E)-phytol as the predominant compound. It was also found in SC-CO₂ extract of freeze-dried C. bursa (FD-CB) as the major constituent. Loliolide (3.51%) was only identified in SC-CO₂ extract. Fatty acids were determined from FD-CB after derivatisation as methyl esters by GC-FID. The most dominant acids were palmitic (25.4%), oleic (36.5%), linoleic (11.6%), and stearic (9.0%). FD-CB H₂O extract exhibited better antifungal effects against Fusarium spp., while dimethyl sulfoxide (DMSO) extract was better for the inhibition of Penicillium expansum, Aspergillus flavus, and Rhizophus spp. The extracts showed relatively good antifungal activity, especially against P. expansum (for DMSO extract MIC₅₀ was at 50 µg/mL).

Organism-derived phthalate derivatives as bioactive natural products

Phthalates are widely used in polymer materials as a plasticizer. These compounds possess potent toxic variations depending on their chemical structures. However, a growing body of evidence indicates that phthalate compounds are undoubtedly discovered in secondary metabolites of organisms, including plants, animals and microorganisms. This review firstly summarizes biological sources of various phthalates and their bioactivities reported during the past few decades as well as their environmental toxicities and public health risks. It suggests that these organisms are one of important sources of natural phthalates with diverse profiles of bioactivity and toxicity.

Codonopilate A, a Triterpenyl Ester as Main Autotoxin in Cultivated Soil of Codonopsis pilosula (Franch.) Nannf

Codonopilate A (1), a triterpenyl ester, was isolated from monocultivated soil of annual Codonopsis pilosula and identified as the main autotoxin. The yield ratio of codonopilate A in dried soil was calculated as 2.04 μg/g. Other two triterpenoids, taraxeryl acetate (2) and 24-methylenecycloartanol (3), were isolated and identified as well showing weaker autotoxity. This was the first time that the potential allelochemicals and autotoxins in the cultivated soil of Codonopsis pilosula were reported. Accumulation of reactive oxygen species (ROS) induced by the autotoxins in the root tips of Codonopsis pilosula was considered as an important factor for the phytotoxic effect. This work systematically investigates the allelopathic and autotoxic effect of Codonopsis pilosula, and the preliminary autotoxic action mode of the three autotoxins. These findings are helpful to understand the molecular mechanism of autotoxicity and conducive to explore proper ways to degrade the autotoxins and eliminate the replanting problems of Codonopsis pilosula.

Bio-Source of di-n-butyl phthalate production by filamentous fungi

Although DBP (di-n-butyl phthalate) is commonly encountered as an artificially-synthesized plasticizer with potential to impair fertility, we confirm that it can also be biosynthesized as microbial secondary metabolites from naturally occurring filamentous fungi strains cultured either in an artificial medium or natural water. Using the excreted crude enzyme from the fungi for catalyzing a variety of substrates, we found that the fungal generation of DBP was largely through shikimic acid pathway, which was assembled by phthalic acid with butyl alcohol through esterification. The DBP production ability of the fungi was primarily influenced by fungal spore density and incubation temperature. This study indicates an important alternative natural waterborne source of DBP in addition to artificial synthesis, which implied fungal contribution must be highlighted for future source control and risk management of DBP.

Contemporary carbon content of bis (2-ethylhexyl) phthalate in butter

The fraction of naturally produced bis (2-ethylhexyl) phthalate (DEHP), a ubiquitous plasticizer known to contaminate packaged foods, was determined for each of five 1.10 kg samples of unsalted market butter by accelerator mass spectrometry (AMS). After extraction and concentration enrichment with liquid-liquid extraction, flash column chromatography, and preparative-scale high performance liquid chromatography, each sample provided ≈ 250 μg extracts of DEHP with carbon purity ranging from 92.5 ± 1.2% (n = 3, 1σ) to 97.1 ± 0.8% (n = 3, 1σ) as measured with gas chromatography mass spectrometry (GC-MS). After corrections for method blank DEHP, co-eluting compounds, and unidentified carbon, the mean fraction of naturally produced DEHP in butter was determined to be 0.16 ± 0.12 (n = 5, 1σ). To our knowledge, this is the first report of the contemporary fraction of DEHP isolated from market butter in the U.S.

Protection of ornamental gold fish Carassius auratus against Aeromonas hydrophila by treating Ixora coccinea active principles

Herbals such as Ixora coccinea, Daemia extensa and Tridax procumbens were selected to screen in vitro antibacterial and immunostimulant activity against the freshwater fish pathogen Aeromonas hydrophila using different organic polar and non-polar solvents. Initial screening results revealed that, ethyl acetate extracts and its purified fraction of I. coccinea was able to suppress the A. hydrophila strains at more than 15 mm of zone of inhibition and positive immunostimulant activity. The purified active fraction, which eluted from H40: EA60 mobile phase was structurally characterized by GC-MS analysis. Two compounds such as Diethyl Phthalate (1,2-Benzene dicarboxylic acid, monobutyl ester) and Dibutyl Phthalate were characterized using NIST database search. In order to study the in vivo immunostimulant influence of the compounds, the crude extracts (ICE) and purified fractions (ICF) were incorporated to the artificial diets at the concentration of 400 mg kg⁻¹ and fed to the ornamental gold fish Carassius auratus for 30 days. After termination of feeding experiment, they were challenged with highly virulent A. hydrophila AHV-1 which was isolated from infected gold fish and studied the survival, specific bacterial load reduction, serum biochemistry, haematology, immunology and histological parameters. The control diet fed fishes succumbed to death within five days at 100% mortality whereas ICE and ICF fed groups survived 60 and 80% respectively after 10 days. The diets also helped to decrease the Aeromonas load after challenge and significantly (P ≤ 0.01) improved the serum albumin, globulin and protein. The diets also helped to increase the RBC and haemoglobin level significantly (P ≤ 0.05) from the control group. Surprisingly the immunological parameters like phagocytic activity, serum bactericidal activity and lysozyme activity were significantly increased (P ≤ 0.001) in the experimental diets. Macrophages and erythrocytes were abundantly expressed in the treated groups and the present work concluded that, the Phthalate derivatives from I. coccinea helps to stimulate the immune system against A. hydrophila challenge in C. auratus.

Phytochemical analysis and antimicrobial activity of Cardaria draba (L.) Desv. volatiles

Two different volatile isolates from the aerial parts of Cardaria draba (L.) Desv., obtained either by hydrodistillation (Extract I) or by CH(2) Cl(2) extraction subsequent to hydrolysis by exogenous myrosinase (Extract II), were characterized by GC-FID and GC/MS analyses. The main volatiles obtained by hydrodistillation, i.e., 4-(methylsulfanyl)butyl isothiocyanate (1; 28.0%) and 5-(methylsulfanyl)pentanenitrile (2; 13.8%), originated from the degradation of glucoerucin. In Extract I, also volatiles without sulfur and/or nitrogen were identified. These were mostly hexadecanoic acid (10.8%), phytol (10.2%), dibutyl phthalate (4.5%), and some other compounds in smaller percentages. Extract II contained mostly glucosinolate degradation products. They originated from glucoraphanin, viz., 4-(methylsulfinyl)butyl isothiocyanate (3; 69.2%) and 5-(methylsulfinyl)pentanenitrile (4; 4.5%), glucosinalbin, viz., 2-(4-hydroxyphenyl)acetonitrile (5; 7.2%), and glucoerysolin, viz., 4-(methylsulfonyl)butyl isothiocyanate (6; 5.0%). Moreover, the volatile samples were evaluated for their antimicrobial activity using the disc-diffusion method and determining minimum inhibitory concentrations (MIC). All volatile isolates expressed a wide range of growth inhibition activity against both Gram-positive and Gram-negative bacteria and fungi. The MIC values varied between 4 and 128 μg/ml.

Hypolipidemic effect of fucoidan from Laminaria japonica in hyperlipidemic rats

In this study, we investigated the effect of fucoidan polysaccharide sulfuric acid ester (FPS) from Laminaria japonica Aresch (Laminariaceae) on hyperlipidemic rats. FPS notably reduced the concentration of serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) of hyperlipidemic rats and increased the concentration of high-density lipoprotein cholesterol (HDL-C) and the activities of lipoprotein lipase (LPL), hepatic lipoprotein (HL), and lecithin cholesterol acyltransferase (LCAT).

A marine sulfate-reducing bacterium producing multiple antibiotics: biological and chemical investigation

A marine sulfate-reducing bacterium SRB-22 was isolated by means of the agar shake dilution method and identified as Desulfovibrio desulfuricans by morphological, physiological and biochemical characteristics and 16S rDNA analysis. In the bioassay, its extract showed broad-spectrum antimicrobial activity using the paper disc agar diffusion method. This isolate showed a different antimicrobial profile than either ampicillin or nystatin and was found to produce at least eight antimicrobial components by bioautography. Suitable fermentation conditions for production of the active constituents were determined to be 28 day cultivation at 25 °C to 30 °C with a 10% inoculation ratio. Under these conditions, the SRB-22 was fermented, extracted and chemically investigated. So far an antimicrobial compound, mono-n-butyl phthalate, and an inactive compound, thymine, have been isolated and characterized.

Production of bioactive metabolites by Nocardia levis MK-VL_113

AIMS

To isolate and identify the bioactive compounds produced by Nocardia levis MK-VL_113.

METHODS AND RESULTS

Cultural characteristics of Noc. levis isolated from laterite soils of Guntur region were recorded on International Streptomyces Project media. Morphological studies of the strain through scanning electron microscopy revealed the clear pattern of its hyphal fragmentation into rod-shaped bacilli. Chemical examination of the secondary metabolites of the strain grown on sucrose-tryptone broth led to the isolation of three fractions active against Bacillus cereus. Further analysis of second fraction resulted in the isolation of two active subfractions. Two different phthalate esters, namely, bis-(2-ethylhexyl) phthalate and bis-(5-ethylheptyl) phthalate, were purified from the first active subfraction, and the structural elucidation of these compounds was confirmed on the basis of FT-IR, mass and NMR spectroscopy. The partially purified second subfraction subjected to Gas Chromatography-Mass spectroscopy contained nine components: decanedioic acid; 2,6-piperdione monooxime; 1-eicosanol; beta-1-arabinopyranoside, methyl; cyclopentaneundecanoic acid; hexadecanoic acid; silane, trichloro eicosyl; 1-hexacosanol; and 1,2-dodecanediol. The antimicrobial activity of the bioactive compounds produced by Noc. levis was expressed in terms of minimum inhibitory concentration.

CONCLUSIONS

The present study clearly revealed that the metabolites of Noc. levis act as bioactive compounds against gram-positive and gram-negative bacteria, yeast and filamentous fungi. It also supports the idea that there are a number of rare actinomycetes remained to be explored for new bioactive compounds.

SIGNIFICANCE AND IMPACT OF THE STUDY

Metabolites of Noc. levis exhibited antibacterial and antifungal activities. This is the first report of bis-(5-ethylheptyl) phthalate as well as the nine partially purified compounds from actinomycetes. In addition, this is also the first report of bis-(2-ethylhexyl) phthalate from the genus Nocardia.

Cathepsin B inhibitory activities of three new phthalate derivatives isolated from seahorse, Hippocampus Kuda Bleeler

Three new phthalate acid derivatives, 2,12-diethyl-11-methylhexadecyl 2-ethyl-11-methylhexadecyl phthalate (1), 2-ethyldecyl 2-ethylundecyl phthalate (2), and bis(2-ethyldodecyl) phthalate (3), were isolated from seahorse, Hippocampus Kuda Bleeler, together with a known natural analog bis(2-ethylheptyl) phthalate (4). The structures of these compounds were elucidated mainly by means of the comprehensive analysis of their NMR spectroscopic data. The four phthalate derivatives showed dose-dependent cathepsin B inhibitions activities with IC(50) values of 0.13 mM (1), 0.21 mM (2), 0.18 mM (3), and 0.29 mM (4), respectively.