RESUMEN
Multivariate pollution degree indices were utilized to evaluate the environmental condition of the Uppanar and Vellar estuaries. The Trophic Index (TRIX) indicates a state of "moderate eutrophication" with a value of 4.92, while the Trophic State Index (TSI) ranged from 40.3 to 57.2, categorizing the trophic states from "oligotrophic" to "eutrophic". The Comprehensive Pollution Index (CPI) showed a range of 0.13 to 0.94, classifying pollution levels from "unpolluted" to "slightly polluted". The study revealed that the Uppanar and Vellar estuaries underwent seasonal variations, transitioning from an oligotrophic state during the post-monsoon and summer periods to a eutrophic state in the pre-monsoon and monsoon seasons. The application of multivariate statistical tools allowed the identification of pollution indicator species to assess the estuarine systems. The insights gained from this study can be valuable for assessing other ecosystems facing similar anthropogenic activities, providing a basis for informed management and conservation strategies.
Asunto(s)
Monitoreo del Ambiente , Estuarios , Eutrofización , Ecosistema , Estaciones del Año , Análisis Multivariante , Animales , Contaminación del Agua/estadística & datos numéricosRESUMEN
The solitary entoproct species, Loxosomella diopatricola is recorded from the Bay of Bengal, southeastern coast of India. The species was found on the eunicid polychaete Diopatra sp. collected from depth of 15 m. Loxosomella diopatricola is a medium-sized species with average body length up to 396 m, eight tentacles and oval in calyx shape. The Loxosomella diopatricola was first time recorded in India. A list of all Loxosomella species associated with polychaetes is given.
Asunto(s)
Bahías , Poliquetos , Animales , IndiaRESUMEN
We report herein three epibiotic associations between peritrich ciliate protozoans and polychaete worms, as observed in Tamilnadu, southeastern coast of India. Epibiont ciliates Epistylis sp.1 were found all over the integument of individuals of the terebellid polychaete Terebella sp., collected from Vellar estuary. Epistylis sp.2 ciliates were observed attached to Namalycastis abiuma polychaetes, on both sides of parapodia. Cothurnia sp. ciliates were found on anterior most paleae and hooks of Sabellaria sp. polychaetes, both latter associations from material from the Uppanar estuary. Those epibiont/basibiont associations are all new to science and discussed herein, together with a review on the previous reports of epibiont ciliate protozoans in Indian waters.
Asunto(s)
Anélidos , Cilióforos , Oligohimenóforos , Poliquetos , Animales , IndiaRESUMEN
Introduction. Streptococcus pyogenes is a diverse virulent synthesis pathogen responsible for invasive systemic infections. Establishment of antibiotic resistance in the pathogen has produced a need for new antibiofilm agents to control the biofilm formation and reduce biofilm-associated resistance development.Aim. The present study investigates the in vitro antibiofilm activity of eucalyptol against S. pyogenes.Methodology. The antibiofilm potential of eucalyptol was assessed using a microdilution method and their biofilm inhibition efficacy was visualized by microscopic analysis. The biochemical assays were performed to assess the influence of eucalyptol on virulence productions. Real-time PCR analysis was performed to evaluate the expression profile of the virulence genes.Results. Eucalyptol showed significant antibiofilm potential in a dose-dependent manner without affecting bacterial growth. Eucalyptol at 300 µg ml-1 (biofilm inhibitory concentration) significantly inhibited the initial stage of biofilm formation in S. pyogenes. However, eucalyptol failed to diminish the mature biofilms of S. pyogenes at biofilm inhibitory concentration and it effectively reduced the biofilm formation on stainless steel, titanium, and silicone surfaces. The biochemical assay results revealed that eucalyptol greatly affects the cell-surface hydrophobicity, auto-aggregation, extracellular protease, haemolysis and hyaluronic acid synthesis. Further, the gene-expression analysis results showed significant downregulation of virulence gene expression upon eucalyptol treatment.Conclusion. The present study suggests that eucalyptol applies its antibiofilm assets by intruding the initial biofilm formation of S. pyogenes. Supplementary studies are needed to understand the mode of action involved in biofilm inhibition.
Asunto(s)
Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Eucaliptol/farmacología , Streptococcus pyogenes/efectos de los fármacos , Streptococcus pyogenes/genética , Factores de Virulencia/genética , Adhesión Bacteriana/efectos de los fármacos , Expresión Génica , Interacciones Hidrofóbicas e Hidrofílicas , Pruebas de Sensibilidad Microbiana , Streptococcus pyogenes/patogenicidad , VirulenciaRESUMEN
The present study evaluated the quebrachitol (QBC) antibiofilm and antivirulence potential against methicillin-resistant Staphylococcus aureus (MRSA). QBC inhibited MRSA biofilm formation at concentration dependent manner without affecting the bacterial growth. Then, QBC biofilm efficacy was confirmed with light and confocal laser scanning microscopy analysis. QBC treatment significantly inhibited the biofilm formation on stainless steel, titanium and silicone surfaces. Besides, QBC treatment significantly reduced the MRSA virulence productions such as lipase and hemolysis. Moreover, it reduced MRSA survival rate in the presence of hydrogen peroxide. QBC treatment inhibited the MRSA adherence on hydrophobic, hydrophilic, collagen coating and fibrinogen coating surfaces. As well as it significantly reduced the autolysin and bacterial aggregation progress. The real-time PCR analysis revealed the ability of QBC downregulated the virulence genes expression including global regulator sarA, agr and polysaccharide intracellular adhesion (PIA) encode ica. The cumulative results of the present study suggest that QBC as a potential agent to combat against MRSA pathogenesis.