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Bajra Napier hybrid (Pennisetum glaucum x Pennisetum purpureum) is a perennial, high yielding grass and is widely grown for fodder in India. During August-2021, Bajra Napier hybrid germplasm line (NBN 15-2) showed severe leaf blight symptoms at ICAR-Indian Grassland and fodder research institute, Jhansi (25.527890 N, 78.5451400 E). Symptoms were initial irregular yellow spots on the leaf lamina, which later became brownish, coalesced and gave blighted appearance to the leaf surface. Disease severity recorded was 55 to 60 percent. To isolate the pathogen, 10 symptomatic leaf samples were cut into small pieces (~4 mm2), surface-sterilized with 70% ethanol for 30 seconds and rinsed with sterile water. Sterilized leaf pieces were transferred to potato dextrose agar (PDA) and incubated at 28°C for 7 days. Four similar fungal isolates (BNHCP-1 to BNHCP-4) were obtained from the affected portions. The colonies were grayish-brown with dark brown margins. Conidia were mostly clavate, elongated, straight or bent at the terminal cell, with 2-3 septa with dimensions of 17.5 to 30 µm × 10 to 12.5 µm (avg. 24 µm × 12 µm; n=40). The third cell from the base was broader and darker. These morphological characteristics were consistent with previous descriptions of Curvularia penniseti (Mitra) Boedijn (Ellis, 1971). To confirm the species, BNHCP-1 was chosen as representative isolate for further studies. Internal transcribed spacer (ITS) region and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene of isolate BNHCP-1 was amplified with primers ITS1F/ITS4R (White et al. 1990) and GDF/GDR (Templeton et al. 1992), and sequenced. The sequences were deposited in GenBank (ITS: OM073980; GAPDH: OM103702.2). BLASTn analysis showed 99.6% and 98% similarity of ITS and GAPDH gene respectively with GenBank accession numbers MH859833.1 (548 bp/550 bp) and MN688838.1 (130 bp/133 bp) of C. penniseti. A maximum-likelihood phylogenetic analysis based on concatenated sequences of ITS and GAPDH gene using MEGA X placed the isolate BNHCP-1 within a clade comprising C. penniseti. Pure culture of BNHCP-1 was deposited in National Agriculturally Important Microbial Culture Collection (NAIMCC), Maunath Bhanjan (Uttar Pradesh) with accession number NAIMCC-F-04251. For pathogenicity, root slips of Bajra Napier hybrid germplasm line NBN 15-2 were transplanted in pots (6 pots; 2 root slips per pot) and kept for fresh growth in a growth chamber at 25 0C for 21 days. Bajra-Napier hybrid plants were sprayed until runoff with conidial suspension (5 × 105 conidia/ml) made from 2-week old fungal colony grown on PDA petri dish. The pots were covered with plastic bag for 48 h to maintain humidity. Inoculated plants displayed small, brown, oval-shaped lesions within seven days on the lamina and edges of the leaf which later enlarged and gave blighted appearance to the leaf. Control plants were asymptomatic. The pathogen was re-isolated from the inoculated leaves and confirmed morphologically, fulfilling Koch's postulates. C. penniseti has been reported earlier from Pennisetum americanum, P. clandestinum, Sorghum and Triticum sp. from different parts of the world (Sivanesan, 1987). However, there is no report of C. penniseti in Bajra Napier hybrid. Thus, to the best of our knowledge, this is the first report of C. penniseti from Bajra-Napier hybrid grass in India. Further studies on economic impact of this disease on Bajra-Napier hybrid production and its presence on commercial cultivars are needed.
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Stable and efficient hydrocarbon degrading microbial consortia were developed from a refinery sludge through nitrate amendment for their application in enhanced bioremediation of petroleum contaminated waste. Nitrate induced biostimulation of refinery sludge resulted in increased abundance of hydrocarbon degrading Rhodocyclaceae, Xanthomonadaceae, Syntrophaceae and Comamonadaceae members. Repeated subculturing of nitrate stimulated communities in crude oil supplemented basal medium was done under aerobic and anaerobic conditions. Aerobically enriched consortia (composed of Pseudomonadaceae, Pseudoxanthomonadaceae and unclassified Comamonadaceae) showed their ability to utilize alkanes, aromatics and crude oil as growth substrates. Anaerobically enriched consortium was predominated by Bacillaceae, Pseudomonadaceae, Xanthomonadaceae, Porphyromonadaceae and Comamonadaceae members. Anaerobic consortium was found to be relatively less efficient in terms of TPH (total petroleum hydrocarbons) degradation compared to its aerobic counterpart. These enriched microbial consortia were finally tested for their biodegradation performance and stability during bioremediation of highly contaminated refinery sludge using different strategies. A 30 days microcosm based bioremediation trial showed that bioaugmentation of aerobic cultures with refinery sludge was more effective in TPH degradation (~ 65% degradation) compared to the anaerobic consortium (only 36% TPH degradation) and a combination of bioaugmentation and nitrate amendment with sludge resulted in enhanced hydrocarbon attenuation (up to 86% TPH degradation). Subsequent community analysis at the end of bioremediation trial confirmed the stability of the added microbial populations. Thus, the strategy of bioaugmentation of specially enriched native microbial populations in combination with nitrate amendment was successfully used for the enhanced bioremediation of petroleum hydrocarbon contaminated refinery waste.
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Bacterias/clasificación , Hidrocarburos/química , Nitratos/metabolismo , Petróleo/metabolismo , Aguas del Alcantarillado/microbiología , Aerobiosis , Anaerobiosis , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Biodegradación Ambiental , ADN Bacteriano/genética , ADN Ribosómico/genética , Consorcios Microbianos , Filogenia , ARN Ribosómico 16S/genética , Aguas del Alcantarillado/químicaRESUMEN
BACKGROUND: Sustainable management of voluminous and hazardous oily sludge produced by petroleum refineries remains a challenging problem worldwide. Characterization of microbial communities of petroleum contaminated sites has been considered as the essential prerequisite for implementation of suitable bioremediation strategies. Three petroleum refinery sludge samples from North Eastern India were analyzed using next-generation sequencing technology to explore the diversity and functional potential of inhabitant microorganisms and scope for their on-site bioremediation. RESULTS: All sludge samples were hydrocarbon rich, anaerobic and reduced with sulfate as major anion and several heavy metals. High throughput sequencing of V3-16S rRNA genes from sludge metagenomes revealed dominance of strictly anaerobic, fermentative, thermophilic, sulfate-reducing bacteria affiliated to Coprothermobacter, Fervidobacterium, Treponema, Syntrophus, Thermodesulfovibrio, Anaerolinea, Syntrophobacter, Anaerostipes, Anaerobaculum, etc., which have been well known for hydrocarbon degradation. Relatively higher proportions of archaea were detected by qPCR. Archaeal 16S rRNA gene sequences showed presence of methanogenic Methanobacterium, Methanosaeta, Thermoplasmatales, etc. Detection of known hydrocarbon utilizing aerobic/facultative anaerobic (Mycobacterium, Pseudomonas, Longilinea, Geobacter, etc.), nitrate reducing (Gordonia, Novosphigobium, etc.) and nitrogen fixing (Azovibrio, Rhodobacter, etc.) bacteria suggested niche specific guilds with aerobic, facultative anaerobic and strict anaerobic populations. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) predicted putative genetic repertoire of sludge microbiomes and their potential for hydrocarbon degradation; lipid-, nitrogen-, sulfur- and methane- metabolism. Methyl coenzyme M reductase A (mcrA) and dissimilatory sulfite reductase beta-subunit (dsrB) genes phylogeny confirmed methanogenic and sulfate-reducing activities within sludge environment endowed by hydrogenotrophic methanogens and sulfate-reducing Deltaproteobacteria and Firmicutes members. CONCLUSION: Refinery sludge microbiomes were comprised of hydrocarbon degrading, fermentative, sulfate-reducing, syntrophic, nitrogen fixing and methanogenic microorganisms, which were in accordance with the prevailing physicochemical nature of the samples. Analysis of functional biomarker genes ascertained the activities of methanogenic and sulfate-reducing organisms within sludge environment. Overall data provided better insights on microbial diversity and activity in oil contaminated environment, which could be exploited suitably for in situ bioremediation of refinery sludge.
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Bacterias Anaerobias/clasificación , Hidrocarburos/metabolismo , Metano/biosíntesis , Petróleo/metabolismo , Aguas del Alcantarillado/microbiología , Bacterias Reductoras del Azufre/clasificación , Archaea/clasificación , Archaea/aislamiento & purificación , Bacterias Anaerobias/aislamiento & purificación , Biodegradación Ambiental , Fermentación , India , Consorcios Microbianos , Petróleo/microbiología , Filogenia , ARN Ribosómico 16S/genética , Bacterias Reductoras del Azufre/aislamiento & purificaciónRESUMEN
Franconibacter pulveris strain DJ34, isolated from Duliajan oil fields, Assam, was characterized in terms of its taxonomic, metabolic and genomic properties. The bacterium showed utilization of diverse petroleum hydrocarbons and electron acceptors, metal resistance, and biosurfactant production. The genome (4,856,096bp) of this strain contained different genes related to the degradation of various petroleum hydrocarbons, metal transport and resistance, dissimilatory nitrate, nitrite and sulfite reduction, chemotaxy, biosurfactant synthesis, etc. Genomic comparison with other Franconibacter spp. revealed higher abundance of genes for cell motility, lipid transport and metabolism, transcription and translation in DJ34 genome. Detailed COG analysis provides deeper insights into the genomic potential of this organism for degradation and survival in oil-contaminated complex habitat. This is the first report on ecophysiology and genomic inventory of Franconibacter sp. inhabiting crude oil rich environment, which might be useful for designing the strategy for bioremediation of oil contaminated environment.
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Enterobacteriaceae/crecimiento & desarrollo , Genoma Bacteriano , Hidrocarburos/metabolismo , Petróleo/microbiología , Composición de Base , Biodegradación Ambiental , Enterobacteriaceae/clasificación , Enterobacteriaceae/genética , Enterobacteriaceae/aislamiento & purificación , Tamaño del Genoma , Filogenia , Análisis de Secuencia de ADNRESUMEN
The microbiological quality of street vended food samples from Dhaka, Bangladesh was evaluated. The objective of the study was to identify the presence of common pathogens (Escherichia coli, Shigella spp, Salmonella and Vibrio spp) and to describe the molecular characterization of E coli, a commonly found pathogen in various street foods. Fifty food samples were collected from fixed and mobile vendors from two sampling locations (Mohakhali and Aftabnagar) in Dhaka city, Bangladesh. The tested samples included deep fried and fried snacks; quick lunch items; pickles; fruit chutney; baked items; spicy, sour and hot snacks etc: Juices, tamarind water and plain drinking water were also tested. Sterile polythene bags were used for collecting 200 g of each category of samples. They were tested for the presence of microorganisms following conventional microbiological processes. Biochemical tests followed by serology were done for the confirmation of Shigella and Salmonella. Serological reaction was carried out for confirmation of Vibrio spp. DNA was isolated for the molecular characterization to detect the pathogenic E. coli by polymerase chain reaction (PCR). Out of 50 food samples, six (12%) were confirmed to contain different species of E. coli and Shigella. Molecular characterization of E. coli revealed that three samples were contaminated with enteroaggregative E. coli (EAEC) and one was contaminated with enterotoxigenic E. coli (ETEC). Shigellaflexneri X variant was detected in one food item and Shigella flexneri 2a was found in drinking water. All these enteric pathogens could be the potential cause for foodborne illnesses.
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Escherichia coli/aislamiento & purificación , Contaminación de Alimentos , Microbiología de Alimentos , Salmonella/aislamiento & purificación , Shigella/aislamiento & purificación , Vibrio/aislamiento & purificación , Bangladesh , Escherichia coli/genética , Manipulación de Alimentos , Humanos , Reacción en Cadena de la Polimerasa , UniversidadesRESUMEN
Botulinum toxin (Botox) injection into the lower esophageal sphincter (LES) has been used for the treatment of achlasia cardia since the 1990s. Currently it is indicated for patients who are not candidates for definitive therapy like Heller's myotomy or pneumatic dilation and in those who have recurrence of symptoms after definitive treatments. We present a case of severe anaphylaxix due to Botox. The purpose of this case is to highlight one of the under-reported adverse effects of Botox. Anaphylactic reactions to Botox are very rare with only one other case being reported and have not been emphasized enough to be widely known in clinical practice.
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Anafilaxia/inducido químicamente , Toxinas Botulínicas Tipo A/efectos adversos , Fármacos Neuromusculares/efectos adversos , Anafilaxia/diagnóstico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: Advances in digital imaging methods have resulted in use of telecytology in the immediate assessment of fine-needle aspiration (FNA) specimens. We retrospectively compared the nondiagnostic rate for endoscopic ultrasound-guided (EUS) FNA of pancreatic lesions in two groups: one with on-site evaluation for adequacy via telecytopathology and the other without on-site adequacy evaluation. SUBJECTS AND METHODS: All patients undergoing EUS-FNA of pancreatic lesions over a 2-year period were included. Direct smears were immediately wet-fixed or air-dried, and any residual material was rinsed in saline for cell block or cytospin preparation. Patients were divided into two groups: Group 1 had on-site telecytopathology evaluation for adequacy by a cytopathologist, and Group 2 had no on-site adequacy evaluation. The cytologic diagnoses were reviewed, and the nondiagnostic rates for each group were calculated. The age, sex, and characteristics of pancreatic lesions (solid versus cystic) between the two groups were compared. RESULTS: In total, 217 patients were included. Telecytopathology on-site evaluation was provided for 95 (43.8%) cases. There was no difference between the groups in terms of age and sex. Pancreatic lesions were predominantly solid in the group that underwent telecytopathology on-site evaluation (p<0.005). The nondiagnostic rates for solid lesions in Group 1 and Group 2 were 3.7% and 25.6%, respectively (p<0.0001). Although the nondiagnostic rate for cystic lesion was higher in Group 2, it did not reach a level of statistical significance (16.5% versus 7.1%; p=0.249). After adjusting for the effects of sex and lesion characteristics (solid versus cystic lesion) with multivariate logistic regression, the odds of having a nondiagnostic specimen in Group 2 was 6.9 times greater than in Group 1, and the result was statistically significant (p=0.0013). CONCLUSIONS: Telecytopathology on-site evaluation of EUS-FNA of pancreatic lesions reduces the nondiagnostic rate, especially in lesions with solid characteristics, and may serve as an effective substitute for on-site evaluation by a cytopathologist.
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Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Enfermedades Pancreáticas/patología , Telepatología/métodos , Anciano , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Interfaz Usuario-ComputadorRESUMEN
Egyptian clover/Berseem (Trifolium alexandrinum L.) is the most popular winter leguminous multi-cut fodder crop widely cultivated in the northwest and central parts of India. Quality seed significantly impacts farm productivity, farmers' profitability, and socioeconomic welfare. Foundation and certified seeds enable high-quality seed production, making breeder seed (BS) the most important link in the seed supply chain. In India, berseem BS indent had increased from 1998 - 99 to 2012-13; afterwards, it followed a constant but decreasing trend. Of the 27 notified cultivars, 24 came into the seed supply chain between 1998-1999 and 2021-2022, indicating high varietal availability to stakeholders. The study examines the potential causes of the national decline in BS indent and production and the differences in these figures over time. The highest BS indent was received for the variety JB-1 (276.1 q), followed by BL-10 (205.1 q), Mescavi (165.6 q) and Wardan (153.7 q) from 1998 - 99 to 2021-22. The varietal replacement rate (VRR) is high, 43.30 %, for the varieties that have reached the age of five or less in the recent three years (2019-20 to 2021-22). Additionally, it has been calculated that if the seed chain operates at 100 % efficiency, the BS generated (48.1q) in 2021-22 can cover an area of almost 0.12 million hectares in 2024-25. The study offers an in-depth overview of berseem BS indent and production, an analysis of the difficulties encountered in BS production, and future directions for expanding variety and producing excess BS in the nation.
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Lucerne (Medicago sativa L.) is the second most significant winter leguminous fodder crop after berseem in India. Breeder seed (BS) is the first stage of the seed production chain, as it is the base material for producing foundation and certified seeds. In India, lucerne BS demand has been reduced by 85.58% during the last 24 years (1998-1999 to 2021-2022), declining from 2150 kg to 310 kg. Out of 14 varieties released and notified so far, only nine varieties entered the seed chain since 1998-1999. It shows narrow varietal diversification and, hence, needs robust breeding programs towards enriching genetic variability and varietal development. The present study also highlights the disparity in BS demand and production over the years and puts forth the possible reasons behind the reduction in BS demand and production in the country. Out of the nine varieties, the BS demand of Anand-2 (53.11%) was highest, followed by Type-9 (19.44%) and RL-88 (13.60%). Varietal replacement rate (VRR) was found to be moderate, i.e., 23.67% for the varieties having <5 years old age in the last 3 years (2019-2020 to 2021-2022). It has also been estimated that BS produced (233 kg) during 2021-2022 can cover the approximate area of 6,300 ha at farmers' fields in 2024-2025 if the seed chain functions 100%, effectively. The present study provides a holistic overview of lucerne BS demand and production, challenges in BS production, and the way forward to develop more varieties and surplus BS production in the country.
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Microbial community analysis of crude oil containing sludge collected from Duliajan oil field, Assam, India, showed the predominance of hydrocarbon-degrading bacteria such as Pseudomonas (20.1%), Pseudoxanthomonas (15.8%), Brevundimonas (1.6%), and Bacillus (0.8%) alongwith anaerobic, fermentative, nitrogen-fixing, nitrate-, sulfate-, and metal-reducing, syntrophic bacteria, and methanogenic archaea. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis indicated gene collection for potential hydrocarbon degradation, lipid, nitrogen, sulfur, and methane metabolism. The culturable microbial community was predominated by Pseudomonas and Bacillus with the metabolic potential for utilizing diverse hydrocarbons, crude oil, and actual petroleum sludge as sole carbon source during growth and tolerating various environmental stresses prevailing in such contaminated sites. More than 90% of the isolated strains could produce biosurfactant and exhibit catechol 2,3-dioxygenase activity. Nearly 30% of the isolates showed alkane hydroxylase activity with the maximum specific activity of 0.54 µmol min-1 mg-1. The study provided better insights into the microbial diversity and functional potential within the crude oil containing sludge which could be exploited for in situ bioremediation of contaminated sites.
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Microbiota , Petróleo , Biodegradación Ambiental , Hidrocarburos , Yacimiento de Petróleo y Gas , Petróleo/análisis , Filogenia , Aguas del AlcantarilladoRESUMEN
BACKGROUND: The genus Trifolium is characterized by typical trifoliolate leaves. Alterations in leaf formats from trifoliolate to multifoliolate, i.e., individual plants bearing trifoliolate, quadrifoliolate, pentafoliolate or more leaflets, were previously reported among many species of the genus. The study is an attempt to develop pure pentafoliolate plants of T. alexandrinum and to understand its genetic control. METHODS: The experimental material consisted of two populations of T. alexandrinum with multifoliolate leaf expression, i.e.,interspecific hybrid progenies of T. alexandrinum with T. apertum, and T. alexandrinum genotype Penta-1. Penetrance of the multifoliolate trait was observed among multifoliolate and trifoliolate plant progenies. In vitro culture and regeneration of plantlets from the axillary buds from different plant sources was also attempted. RESULTS: The inheritance among a large number of plant progenies together with in vitro micro-propagation results did not establish a definite pattern. The multifoliolate leaf formation was of chimeric nature, i.e., more than one leaf format appearing on individual branches. Reversal to normal trifoliolate from multifoliolate was also quite common. Penetrance and expression of multifoliolate leaf formation was higher among the plants raised from multifoliolate plants. Multifoliolate and pure pentafoliolate plants were observed in the progenies of pure trifoliolate plants and vice-versa. There was an apparent increase in the pentafoliolate leaf formation frequency over the years due to targeted selection. A few progenies of the complete pentafoliolate plants in the first year were true breeding in the second year. Frequency of plantlets with multifoliolate leaf formation was also higher in in vitro axillary bud multiplication when the explant bud was excised from the multifoliolate leaf node. CONCLUSION: Number of leaflets being a discrete variable, occurrence of multifoliolate leaves on individual branches, reversal of leaf formats on branches and developing true breeding pentafoliolates were the factors leading to a hypothesis beyond normal Mendelian inheritance. Transposable elements (TEs) involved in leaf development in combination with epigenetics were probably responsible for alterations in the expression of leaflet number. Putative TE's movement owing to chromosomal rearrangements possibly resulted in homozygous pentafoliolate trait with evolutionary significance. The hypothesis provides a new insight into understanding the genetic control of this trait in T. alexandrinum and may also be useful in other Trifolium species where such observations are reported.
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Apomixis is a method of reproduction to generate clonal seeds and offers tremendous potential to fix heterozygosity and hybrid vigor. The process of apomictic seed development is complex and comprises three distinct components, viz., apomeiosis (leading to formation of unreduced egg cell), parthenogenesis (development of embryo without fertilization) and functional endosperm development. Recently, in many crops, these three components are reported to be uncoupled leading to their partitioning. This review provides insight into the recent status of our understanding surrounding partitioning apomixis components in gametophytic apomictic plants and research avenues that it offers to help understand the biology of apomixis. Possible consequences leading to diversity in seed developmental pathways, resources to understand apomixis, inheritance and identification of candidate gene(s) for partitioned components, as well as contribution towards creation of variability are all discussed. The potential of Panicum maximum, an aposporous crop, is also discussed as a model crop to study partitioning principle and effects. Modifications in cytogenetic status, as well as endosperm imprinting effects arising due to partitioning effects, opens up new opportunities to understand and utilize apomixis components, especially towards synthesizing apomixis in crops.
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Background In the present study, we investigated the antibacterial, anthelmintic, and analgesic activities of methanol extract of P. sylvaticum leaves (MEPSL) in experimental models. Then, computational analysis (in silico molecular docking and PASS prediction) was performed to determine the potent phytoconstituents of total six isolated compounds of this plant for antibacterial and anthelmintic activities. Methods Qualitative and quantitative phytochemical studies were carried out by established methods. In vitro antibacterial activity was determined by disc diffusion technique and anthelmintic activity was tested against Tubifex tubifex worm whereas analgesic activity was determined by the acetic acid-induced writhing test in mice. Molecular docking study was performed using Schrödinger Maestro 10.1 and an online tool used for PASS prediction. Results Our phytochemical study revealed the presence of alkaloids, flavonoids, saponins, and also indicated a substantial amount of phenols (65.83 mg), flavonoids (102.56 mg), and condensed tannins (89.32 mg). MEPSL showed good antibacterial activity against both gram-positive and gram-negative bacteria. Our result exhibited that MEPSL has strong anthelmintic action compared to standard levamisole. In addition, the extract also showed a dose-dependent and statistically significant analgesic activity at the doses of 200 and 400 mg/kg, body weight. Docking studies showed that piperine and piperlonguminine have the best scores for the tested enzymes. PASS predicted the antibacterial and anthelmintic activity of both phytoconstituents. Conclusions This study suggests that MEPSL possess significant antibacterial, anthelmintic, and analgesic activities which could be related to the presence of several phytochemicals. The phytoconstituents, i.e. piperine and piperlonguminine were found to be most effective in computational studies.
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Analgésicos/farmacología , Antihelmínticos/farmacología , Antibacterianos/farmacología , Piper/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Alcaloides/farmacología , Animales , Benzodioxoles/farmacología , Dioxolanos/farmacología , Ratones , Pruebas de Sensibilidad Microbiana , Simulación del Acoplamiento Molecular , Oligoquetos/efectos de los fármacos , Piperidinas/farmacología , Alcamidas Poliinsaturadas/farmacologíaRESUMEN
Scope for developing an engineered bioremediation strategy for the treatment of hydrocarbon-rich petroleum refinery waste was investigated through biostimulation and bioaugmentation approaches. Enhanced (46-55%) total petroleum hydrocarbon (TPH) attenuation was achieved through phosphate, nitrate or nitrate+phosphate amendment in the sludge with increased (upto 12%) abundance of fermentative, hydrocarbon degrading, sulfate-reducing, CO2-assimilating and methanogenic microorganisms (Bacillus, Coprothermobacter, Rhodobacter, Pseudomonas, Achromobacter, Desulfitobacter, Desulfosporosinus, T78, Methanobacterium, Methanosaeta, etc). Together with nutrients, bioaugmentation with biosurfactant producing and hydrocarbon utilizing indigenous Bacillus strains resulted in 57-75% TPH reduction. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis revealed enhanced gene allocation for transporters (0.45-3.07%), ABC transporters (0.38-2.07%), methane (0.16-1.06%), fatty acid (0.018-0.15%), nitrogen (0.07-0.17%), butanoate (0.06-0.35%), propanoate (0.004-0.26%) metabolism and some xenobiotics (0.007-0.13%) degradation. This study indicated that nutrient-induced community dynamics of native microorganisms and their metabolic interplay within oil refinery sludge could be a driving force behind accelerated bioremediation.
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Biodegradación Ambiental , Aguas del Alcantarillado , Contaminantes del Suelo , Hidrocarburos , Petróleo , Filogenia , Microbiología del SueloRESUMEN
Intrinsic biodegradation potential of bacteria from petroleum refinery waste was investigated through isolation of cultivable strains and their characterization. Pseudomonas and Bacillus spp. populated the normal cultivable taxa while prolonged enrichment with hydrocarbons and crude oil yielded hydrocarbonoclastic bacteria of genera Burkholderia, Enterobacter, Kocuria, Pandoraea, etc. Strains isolated through enrichment showed assemblages of superior metabolic properties: utilization of aliphatic (C6-C22) and polyaromatic compounds, anaerobic growth with multiple terminal electron acceptors and higher biosurfactant production. Biodegradation of dodecane was studied thoroughly by GC-MS along with detection of gene encoding alkane hydroxylase (alkB). Microcosms bioaugmented with Enterobacter, Pandoraea and Burkholderia strains showed efficient biodegradation (98% TPH removal) well fitted in first order kinetic model with low rate constants and decreased half-life. This study proves that catabolically efficient bacteria resides naturally in complex petroleum refinery wastes and those can be useful for bioaugmentation based bioremediation.
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Biodegradación Ambiental , Hidrocarburos , Petróleo , Bacterias , Contaminantes del SueloRESUMEN
Nutrient deficiency severely impairs the catabolic activity of indigenous microorganisms in hydrocarbon rich environments (HREs) and limits the rate of intrinsic bioremediation. The present study aimed to characterize the microbial community in refinery waste and evaluate the scope for biostimulation based in situ bioremediation. Samples recovered from the wastewater lagoon of Guwahati refinery revealed a hydrocarbon enriched [high total petroleum hydrocarbon (TPH)], oxygen-, moisture-limited, reducing environment. Intrinsic biodegradation ability of the indigenous microorganisms was enhanced significantly (>80% reduction in TPH by 90 days) with nitrate amendment. Preferred utilization of both higher- (>C30) and middle- chain (C20-30) length hydrocarbons were evident from GC-MS analysis. Denaturing gradient gel electrophoresis and community level physiological profiling analyses indicated distinct shift in community's composition and metabolic abilities following nitrogen (N) amendment. High throughput deep sequencing of 16S rRNA gene showed that the native community was mainly composed of hydrocarbon degrading, syntrophic, methanogenic, nitrate/iron/sulfur reducing facultative anaerobic bacteria and archaebacteria, affiliated to γ- and δ-Proteobacteria and Euryarchaeota respectively. Genes for aerobic and anaerobic alkane metabolism (alkB and bssA), methanogenesis (mcrA), denitrification (nirS and narG) and N2 fixation (nifH) were detected. Concomitant to hydrocarbon degradation, lowering of dissolve O2 and increase in oxidation-reduction potential (ORP) marked with an enrichment of N2 fixing, nitrate reducing aerobic/facultative anaerobic members [e.g., Azovibrio, Pseudoxanthomonas and Comamonadaceae members] was evident in N amended microcosm. This study highlighted that indigenous community of refinery sludge was intrinsically diverse, yet appreciable rate of in situ bioremediation could be achieved by supplying adequate N sources.
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We report here the 4,856,096-bp draft genome sequence of hydrocarbon-degrading Cronobacter sp. strain DJ34 isolated from crude oil-containing sludge from the Duliajan oil fields, India. DJ34 contains genes that mediate hydrocarbon degradation, metal resistance, and biosurfactant production. This is the first report of the genome sequence of Cronobacter sp. inhabiting an oil-contaminated environment.
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BACKGROUND: Sugarcane is an important cash crop, providing 70% of the global raw sugar as well as raw material for biofuel production. Genetic analysis is hindered in sugarcane because of its large and complex polyploid genome and lack of sufficiently informative gene-tagged markers. Modern genomics has produced large amount of ESTs, which can be exploited to develop molecular markers based on comparative analysis with EST datasets of related crops and whole rice genome sequence, and accentuate their cross-technical functionality in orphan crops like tropical grasses. FINDINGS: Utilising 246,180 Saccharum officinarum EST sequences vis-à-vis its comparative analysis with ESTs of sorghum and barley and the whole rice genome sequence, we have developed 3425 novel gene-tagged markers - namely, conserved-intron scanning primers (CISP) - using the web program GeMprospector. Rice orthologue annotation results indicated homology of 1096 sequences with expressed proteins, 491 with hypothetical proteins. The remaining 1838 were miscellaneous in nature. A total of 367 primer-pairs were tested in diverse panel of samples. The data indicate amplification of 41% polymorphic bands leading to 0.52 PIC and 3.50 MI with a set of sugarcane varieties and Saccharum species. In addition, a moderate technical functionality of a set of such markers with orphan tropical grasses (22%) and fodder cum cereal oat (33%) is observed. CONCLUSIONS: Developed gene-tagged CISP markers exhibited considerable technical functionality with varieties of sugarcane and unexplored species of tropical grasses. These markers would thus be particularly useful in identifying the economical traits in sugarcane and developing conservation strategies for orphan tropical grasses.
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Biocombustibles , Productos Agrícolas , Etiquetas de Secuencia Expresada , Marcadores Genéticos , Poaceae/genética , Saccharum/genética , ADN de Plantas/genética , Reacción en Cadena de la Polimerasa , Polimorfismo GenéticoRESUMEN
We evaluated dynamic telecytopathology for on-site-evaluation of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) samples of the pancreas. Realtime images of stained cytology smears were assessed by a cytopathologist while communicating with the on-site operator by telephone. A total of 55 consecutive cases was assessed; preliminary diagnoses of benign, atypical/suspicious and positive for malignancy were 69%, 7% and 24%. We also reviewed 55 consecutive cases of EUS-guided FNA of pancreas which had had conventional microscopic on-site evaluation prior to the introduction of telecytopathology. Preliminary diagnoses of benign, atypical/suspicious and positive for malignancy were 60%, 9% and 31%. The overall concordance between the preliminary and final diagnosis was 84% for telecytopathology and 87% for conventional microscopy. Neuroendocrine neoplasms and well-differentiated adenocarcinoma were diagnostically challenging for both telecytopathology and conventional microscopy. Telecytopathology was similar in accuracy of preliminary diagnosis to conventional microscopy during EUS-FNA of pancreas.