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1.
Environ Monit Assess ; 195(12): 1413, 2023 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-37924359

RESUMO

Little information exists on the fate and impacts of boats constructed of fibreglass reinforced plastic (FRP) once they reach their end-of-life. In this study, the number of abandoned fishing boats constructed of FRP or constructed of plywood-wood and sheathed by FRP has been determined along the coast of Kerala, India, and chemical emissions have been estimated when boats are burned as a means of disposal. A total of 292 abandoned boats were observed across eight coastal transects constructed around selected landing centres, with abandonment ranging from 13 to 48 per km (average = 29 km-1). This results in the generation of 1420 kg of FRP debris (glass mat and epoxy resin) per km of coastline. A controlled combustion experiment, simulating open burning, revealed that 63% of original boat mass is emitted to the atmosphere, with the remainder forming a burnt residue. Total concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans emitted and remaining were found to be 2.6 ng Nm-3 and 249.6 µg kg-1, respectively, with respective calculated toxicity equivalence (TEQ) levels of 437.6 pg TEQ Nm-3 in air emissions and 26.6 µg TEQ kg-1 in the residue. These figures are equivalent to the total emission from FRP boat burning of about 17,000 µg TEQ t-1. Burning also generates significant quantities of potentially toxic metals, with resulting concentrations of Co, Cr and Cu close to or exceeding soil guideline values. The study calls for a greater awareness of the impacts arising from boat abandonment and burning amongst fishermen, and guidelines or regulatory protocols regarding safe and sustainable boat disposal or recycling.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Incineração , Navios , Caça , Monitoramento Ambiental , Dibenzofuranos Policlorados/análise
2.
Mar Pollut Bull ; 192: 114980, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37209660

RESUMO

Plastics and microplastics have been quantified and characterised at disposal sites of abandoned fishing boats and along the high-water line (HWL) of a fish landing centre in Chellanam, India. Fibreglass-reinforced plastic (FRP) made a greater contribution to the plastic pool at the disposal sites (~ 4.5 n m-2 and 18 g m-2) than the HWL (~ 0.25 n m-2 and < 1 g m-2) and was an abundant component of the microplastic pool at the former. Infrared analysis of micro-sized FRPs revealed various resins (e.g., alkyd, polyester, epoxy), while X-ray fluorescence analysis of the painted surfaces of meso-sized FRPs returned variable concentrations of copper and lead. Concentrations of Pb were high enough to contaminate sand up to ~400 mg kg-1. The relatively high density of FRP and its association with glass fibres and metal-bearing paints results in particles with potentially very different fates and toxicities to more "conventional" (non-composite) thermoplastics.


Assuntos
Plásticos , Poluentes Químicos da Água , Animais , Plásticos/análise , Microplásticos/análise , Caça , Navios , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Índia , Água/análise
3.
Heliyon ; 9(4): e15219, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37095901

RESUMO

The organic 3-hydroxy-4-methoxybenzaldehyde single crystal has been grown by the slow evaporation technique. Single crystal X-ray diffraction (XRD) study shows that the grown crystal belongs to a monoclinic crystal system with centrosymmetric space group P21/c. The spectral analysis of 3-hydroxy-4-methoxybenzaldehyde calculations was performed with the help of DFT at the B3LYP/6-311 + G(d,p) level of theory. The experimental results of FTIR and FT-Raman were compared with the computational results. Detailed interpretations of the vibrational spectra were carried out with the aid of vibrational energy distribution analysis using potential energy distribution (PED) analysis and vibrational wavenumber scaled by the WLS (Wavenumber Linear Scaling) method. The natural bond orbital (NBO) analysis was carried out to identify intramolecular hydrogen bonding. The optical properties of the grown crystal were analyzed by UV-Visible studies. Photoluminescence studies show that the high-intensity peak observed around 410 nm. The laser damage threshold value of the grown crystal has been determined using an Nd:YAG laser operating at 1064 nm. The HOMO (Highest Occupied Molecular Orbital) - LUMO (Lowest Unoccupied Molecular Orbital) was used to identify the energy gap. Hirshfeld Surface (HS) analysis was used to determine the intermolecular interactions. The thermal properties of the grown crystal were performed by Thermogravimetric (TG) and Differential thermal analyses (DTA). The kinetic and thermodynamic parameters were calculated. The surface morphology of the grown crystal was studied by using Scanning Electron Microscopy (SEM) analysis. The antibacterial and antifungal studies were analyzed.

4.
Nat Prod Res ; 35(13): 2269-2273, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31542951

RESUMO

The volatile chemicals in the leaves of six Garcinia species viz; G. assamica, G. dulcis, G. lanceifolia, G. morella var. mucrona, G. pedunculata and G. xanthochymus, collected from North East India, were studied for the first time. The essential oils obtained by hydrodistillation were analyzed by GC-FID and GC-MS, and 64 volatile components were identified. Sesquiterpene hydrocarbons predominated in all the species, and the major compounds were (E)-caryophyllene, α-copaene and ß-selinene. The characteristic compound α-copaene was distinguished from its isomer α-ylangene through 13C NMR analysis. Hierarchical cluster analysis based on the volatile chemical compositions revealed that G. dulcis and G. xanthochymus are very close to each other. The compositions of North East Garcinia species were compared with that of the Western Ghats species.


Assuntos
Garcinia/química , Folhas de Planta/química , Compostos Orgânicos Voláteis/análise , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Cromatografia Gasosa-Espectrometria de Massas , Índia , Óleos Voláteis/química , Sesquiterpenos
5.
Fitoterapia ; 143: 104592, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32278024

RESUMO

Two new caged xanthones, wightiic acid (1) 16-O-methyl wightiic acid (2), along with eight known compounds, gaudichaudic acid E (3), isogaudichaudic acid E (4), ursolic acid (5) stigmasterol (6), lupeol (7), glutinol (8), lupenone (9) and stigmasteryl linoleate (10) were isolated from Garcinia wightii T. Anderson. The structures of the compounds were elucidated by spectroscopic means, including 1D and 2D NMR, HR-ESIMS, and the absolute configuration of the new compounds 1 and 2 were determined by analysis of ECD data. Anti-proliferation activities of the four caged xanthones (1-4) were evaluated by MTT assay on MCF-7 and SKBR-3 human breast cancer cells and A-375 human melanoma cells by MTT assay. All the tested compounds exhibited dose dependent antiproliferative activity. Wightiic acid (1) showed remarkable activity with IC50 value of 4.7 µM and 5.2 µM respectively in A-375 and MCF-7 cells. The compound isogaudichaudic acid E (4) induced potent antiproliferation against SKBR-3 cells with an IC50 value of 6.1 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Garcinia/química , Folhas de Planta/química , Xantonas/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Índia , Células MCF-7 , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Xantonas/isolamento & purificação
6.
Indian J Med Res ; 147(2): 133-141, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29806601

RESUMO

Cholera, caused by the Gram-negative bacterium Vibrio cholerae, has ravaged humanity from time immemorial. Although the disease can be treated using antibiotics along with administration of oral rehydration salts and controlled by good sanitation, cholera is known to have produced mayhems in ancient times when little was known about the pathogen. By the 21st century, ample information about the pathogen, its epidemiology, genetics, treatment and control strategies was revealed. However, there is still fear of cholera outbreaks in developing countries, especially in the wake of natural calamities. Studies have proved that the bacterium is mutating and evolving, out-competing all our efforts to treat the disease with previously used antibiotics and control with existing vaccines. In this review, the major scientific insights of cholera research are discussed. Considering the important role of biofilm formation in the V. cholerae life cycle, the vast availability of next-generation sequencing data of the pathogen and multi-omic approach, the review thrusts on the identification of suitable biofilm-inhibiting targets and the discovery of anti-biofilm drugs from nature to control the disease.


Assuntos
Cólera/epidemiologia , Cólera/terapia , Vibrio cholerae O1/patogenicidade , Antibacterianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Cólera/genética , Cólera/microbiologia , Surtos de Doenças , Humanos
7.
J Food Prot ; 80(11): 1933-1940, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29053421

RESUMO

Vibrio cholerae, a causative agent of the waterborne disease cholera, still threatens a large proportion of world's population. The role of biofilm formation in V. cholerae pathogenesis is well established, as it provides the bacterium enhanced tolerance to antimicrobial agents and increased transmission. In the present study, four medicinal plants used in traditional medicines with antidiarrheal properties were evaluated for its antibiofilm activity. Methanol extracts of these plants (Centella asiatica, Elephantopus scaber, Camellia sinensis, and Holarrhena antidysenterica) showed promising antibiofilm activity against V. cholerae with crystal violet and air-liquid interface coverslip assays. Results revealed that C. asiatica, E. scaber, C. sinensis, and H. antidysenterica extracts significantly inhibited biofilm formation by approximately 75, 76, 78, and 55% at concentrations of 3, 2, 1, and 0.6 mg/mL, respectively. A promising antibiofilm activity of ∼89% inhibition at 1.5 mg/mL concentration was observed when a combination of E. scaber and C. sinensis was used. The herbal extracts were thermostable at a temperature range of 40 to 100°C. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay revealed that the viability of bacteria was not affected by treatment with these plant extracts. Gene expression studies revealed that extracts of H. antidysenterica leaf, H. antidysenterica bark, and the whole plant of E. scaber and C. asiatica down-regulate aphA or aphB, the major regulator genes modulating both virulence and biofilm formation. Hence, we propose that these herbal combinations could serve as a multifaceted approach to combat the pathogen and also, in turn, reduce antimicrobial resistance development.

8.
J Appl Microbiol ; 122(3): 698-707, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27868364

RESUMO

AIMS: Production and characterization of polyhydroxybutyrate (PHB) from moderately halophilic bacterium Vibrio harveyi MCCB 284 isolated from tunicate Phallusia nigra. METHODS AND RESULTS: Twenty-five bacterial isolates were obtained from tunicate samples and three among them exhibited an orange fluorescence in Nile red staining indicating the presence of PHB. One of the isolates, MCCB 284, which showed rapid growth and good polymer yield, was identified as V. harveyi. The optimum conditions of the isolate for the PHB production were pH 8·0, sodium chloride concentration 20 g l-1 , inoculum size 0·5% (v/v), glycerol 20 g l-1 and 72 h of incubation at 30°C. Cell dry weight (CDW) of 3·2 g l-1 , PHB content of 2·3 g l-1 and final PHB yield of 1·2 g l-1 were achieved. The extracted PHB was characterized by FTIR, NMR and DSC-TGA techniques. CONCLUSIONS: An isolate of V. harveyi that could effectively utilize glycerol for growth and PHB accumulation was obtained from tunicate P. nigra. PHB produced was up to 72% based on CDW. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of an isolate of V. harveyi which utilizes glycerol as the sole carbon source for PHB production with high biomass yield. This isolate could be of use as candidate species for commercial PHB production using glycerol as the feed stock or as source of genes for recombinant PHB production or for synthetic biology.


Assuntos
Carbono/metabolismo , Glicerol/metabolismo , Hidroxibutiratos/metabolismo , Vibrio/metabolismo , Biomassa , Hidroxibutiratos/química , Polímeros
9.
Pediatr Blood Cancer ; 61(5): 865-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24249385

RESUMO

BACKGROUND: This study evaluates the effectiveness and interpretation of hepatitis B (HBV) screening in an at-risk cohort of children with cancer or blood disorders. PROCEDURE: We conducted a retrospective epidemiologic analysis of children who screened positive for HBV (HBsAg, HbcAb) from 1999 to 2009 at a quaternary children's hospital, focusing on patients with hematologic and oncologic conditions. Descriptive statistics were generated for demographics and serologies. Follow-up of positive serologies and clinical outcomes were analyzed. RESULTS: A total of 12,754 children were screened for HBV. Of 391 that screened positive, 118 had a hematologic or oncologic diagnosis. Leukemia, anemia, and thrombocytopenia comprised 84% of diagnoses. The majority (98%) tested HBcAb positive but only 20% received confirmatory HBV DNA testing. Three patients (13% of those HBV DNA tested) were identified to have chronic disease. HBV was not a known pre-existing condition, and chemotherapy preceded HBV diagnosis in all cases. CONCLUSIONS: The majority of children with cancer or blood disorders who screened HBV positive did not receive follow-up DNA testing, exposing them to reactivation risk and delaying definitive therapy. HBcAb may be the only indicator of chronic HBV infection and DNA confirmation should be routine. Our findings suggest a significant number of additional patients eligible for HBV treatment may have been identified with reflexive DNA testing.


Assuntos
Doenças Hematológicas/diagnóstico , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Vírus da Hepatite B/patogenicidade , Hepatite B/diagnóstico , Programas de Rastreamento , Neoplasias/diagnóstico , Adolescente , Criança , Pré-Escolar , DNA Viral/sangue , DNA Viral/genética , Feminino , Seguimentos , Doenças Hematológicas/virologia , Hepatite B/virologia , Vírus da Hepatite B/genética , Humanos , Lactente , Masculino , Neoplasias/virologia , Prognóstico , Estudos Retrospectivos , Texas/epidemiologia , Ativação Viral
10.
Anc Sci Life ; 12(1-2): 299-308, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22556607

RESUMO

Janakia arayalpatra (Periplocaceae) known to the local kani tribe as 'Amruthapala' is a rare and endemic wild plant species of southern forested region of Western Ghats. The medicinal value of this plant as a potential drug was reported by the authors earlier (on the basis of the information collected from the Kani tribe). Preliminary ethnopharmacological investigation of the plant showed promising results. In view of the emerging medical importance of this plant, a detailed pharmacognostical investigation of this plant species was carried out. The plant species is now placed under the family periploaceae which was formerly considered to be a sub-division of the family Asclepiadaceae. Pharmacognostical investigation of the root of this plant showed certain characterstic anatomical features like those of the Asclepiadaceae. The aroma and physical characterstics of the roots have close resemblance with plant species like Utleria salicifolia Bedd. and Hemidesmus indicus R. Br.

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