Extraction of cellulose from halophytic plants for the synthesis of a novel biocomposite.

Cellulose nanofibers, a sustainable and promising material with widespread applications, exhibit appreciable strength and excellent mechanical and physicochemical properties. The preparation of cellulosic nanofibers from food or agricultural residue is not sustainable. Therefore, this study was designed to use three halophytic plants (Cressa cretica, Phragmites karka, and Suaeda fruticosa) to extract cellulose for the subsequent conversion to cellulosic nanofibers composites. The other extracted biomass components including lignin, hemicellulose, and pectin were also utilized to obtain industrially valuable enzymes. The maximum pectinase (31.56 IU mL-1), xylanase (35.21 IU mL-1), and laccase (15.89 IU mL-1) were produced after the fermentation of extracted pectin, hemicellulose, and lignin from S. fruticosa, P. karka, and C. cretica, respectively. Cellulose was methylated (with a degree of substitution of 2.4) and subsequently converted into a composite using polyvinyl alcohol. Scanning electron microscopy and Fourier-transform infrared spectroscopy confirmed the successful synthesis of the composites. The composites made up of cellulose from C. cretica and S. fruticosa had a high tensile strength (21.5 and 15.2 MPa) and low biodegradability (47.58% and 44.56%, respectively) after dumping for 3 months in soil, as compared with the composite from P. karka (98.79% biodegradability and 4.9 MPa tensile strength). Moreover, all the composites exhibited antibacterial activity against gram-negative bacteria (Escherichia coli and Klebsiella pneumoniae) and gram-positive bacteria (Staphylococcus aureus). Hence, this study emphasizes the possibility for various industrial applications of biomass from halophytic plants.

Phytoremediation of an integrated poultry and aquaculture wastewater using sub-surface constructed wetland planted with Phragmites karka and Typha latifolia.

This study focused on assessing the effectiveness of vertical subsurface constructed wetlands (VSFCW) in purifying integrated poultry and aquaculture wastewater (PAW) in a tropical region. This evaluation encompassed the treatment of physico-chemical, heavy metal, and microbiological pollutants across three distinct climatic seasons and hydraulic retention time (HRT: 21 days). Parameters such as BOD (29.50 mg/L), COD (56.67 mg/L), Zn (2.97 mg/L), Cr (0.24 mg/L), Cu (1.78 mg/L), Pb (0.21 mg/L), total fecal coliform (866.67 cfu/mL), total coliform (1666.67 cfu/mL), E. coli (1133.33 cfu/mL), and Salmonella/Shigella (700 cfu/mL) exceeded the discharge limits for wastewater into nearby surface water bodies. Significant removal efficiencies were observed for all parameters tested in the CW planted with both Phragmites karka and Typha latifolia. The macrophytes showed similar removal efficiencies for all tested parameters, and there was no significant difference in the initial concentrations of the parameters based on the experimental season, except for microbial properties. This suggests that weather conditions did not significantly impact the concentration of physical and chemical properties in the wastewater. Consequently, this study successfully demonstrates the potential of using a VSFCW for effective treatment of PAW.

Leveraging the power of nature's green allies, Phragmites karka and Typha latifolia, a Sub-surface Constructed Wetland becomes a dynamic and efficient solution. This innovative strategy not only effectively addresses the wastewater challenge but also promotes sustainability and ecological balance. By harnessing the extraordinary capabilities of these wetland plants, the integrated system showcases its potential to transform waste into a valuable resource while minimizing the environmental footprint. In a world that demands sustainable solutions, this pioneering approach paves the way for a greener future in wastewater treatment for Integrated Poultry and Aquaculture industries.

Enhanced atrazine removal by hydrophyte-bacterium associations and in vitro screening of the isolates for their plant growth-promoting potential.

Emergent hydrophytes Acorus calamus, Typha latifolia, and Phragmites karka and epiphytic root bacteria isolated from their rhizoplanes were exposed to atrazine (5 and 10 mg l-1) individually and in plant-bacterium combination for 15 days hydroponically. It was observed that A. calamus-Pseudomonas sp. strain, the ACB combination, was best in decontamination, showing 91% and 87% removal of 5 and 10 mg l-1 atrazine. Plant-bacterium association led to significant increase in atrazine decontamination as compared to decontamination by either plant or bacterium alone, indicating a synergistic action of the hydrophytes and isolates which led to enhanced atrazine removal. To the best of our knowledge this is the first report on the potential of plant-bacterium combinations for atrazine decontamination. The isolates showed augmented growth in the presence of plants and were able to alleviate atrazine stress in them. These isolates exhibited plant growth-promoting traits such as auxin, siderophore, Poly(3-hydroxybutyric acid)/succinogycan, ammonia, catalase production and solubilization of inorganic phosphate in vitro. The use of plant-bacterium mutualistic symbiosis for atrazine mitigation is a relatively simple, inexpensive, and clean technique and this phytoremediation-rhizoremediation combination is suggested to be tried on field to establish their potential for clean-up of contaminated sites.

Assessing the Bacterial Community Structure in the Rhizoplane of Wetland Plants.

Plant-microorganism interaction in the rhizosphere is important for nutrient cycling, carbon sequestration in natural ecosystems, contaminant elimination and ecosystem functioning. Abundance of microbial communities and variation in species composition can be an imperative determinant of phytoremediation capability. In the present study we have assessed the bacterial community structure in the rhizoplane of wetland plants, Acorus calamus, Typha latifolia, and Phragmites karka using Terminal restriction fragment length polymorphism technique. The most dominant phylum, in the plants under study, was phylum Firmicutes, followed by Proteobacteria and Actinobacteria. Bacterial groups belonging to phylum Chloroflexi, Acidobacteria, Deferribacteres and Thermotogae also showed their presence in P. karka and T. latifolia but were absent in A. calamus. Diversity indices of bacterial community were assessed. The results of this study show the presence of bacterial phyla which play an important role in bioremediation of contaminants. Thus these plants can be used as potential candidates of phytoremediation.

Phytoremediation of Water Using Phragmites karka and Veteveria nigritana in Constructed Wetland.

Constructed wetland is an innovative and emerging ecological technology for wastewater treatment. This study was conducted to investigate the effectiveness of a Vegetated Submerged Bed Constructed Wetland (VSBCW) for removal of heavy metals from industrial wastewater in a steel manufacturing company. A pilot Effluent Treatment Plant (ETP) consisting of equalization basin, two VSBCW basins and a storage tank was constructed. The VSBCW was constructed using 10-30 mm round granite for the different zones. This was overlaid by 200 mm deep granite and 150 mm washed sand with Phragmites karka, Vetiveria nigritana and Cana lilies as macrophytes. Irrigation of macrophytes using effluent from the industry was done after 3 months of planting and ETP monitored. Industrial wastewater samples were collected and analyzed for heavy metals such as zinc (Zn), lead (Pb), iron (Fe), manganese (Mn), magnesium (Mg) and chromium (Cr) to know the treatment efficiency of the ETP. Results indicated that the removal efficiencies of the VSBCW for Pb, Mg and Cr were 15.4%, 79.7% and 97.9% respectively. Fe and Mn were seen to increase by 1.8% and 33% respectively. The ETP using locally available macrophytes is effective in the phytoremediation of heavy metals, particularly Cr from the wastewater.

Feasibility Study of Phragmites karka and Christella dentata Grown in West Bengal as Arsenic Accumulator.

A survey was undertaken, in arsenic (As) contaminated area of the Nadia district, West Bengal, India, to find native As accumulator plants. As was determined both in soil and plant parts. The results showed that the mean translocation factor of Pteris vittata L, Phragmites karka (Cav.) Trin. Ex. Steud and Christella dentata Forssk were higher than 1. It thus appeared that these plants can be efficient accumulators of As. Phytoremediation ability of C. dentata and P. karka was evaluated and compared with known As-hyperaccumulators -P. vittata and Adiantum capillus veneris L. Plants were grown in the As spiked soil (25, 50, 75 and 100 mg kg(-1)). As accumulation was found to be highest in P. vittata, 117.18 mg kg(-1) in leaf at 100 mg kg(-1) As treatment, followed by A. capillus veneris, P. karka and C. dentata being 74, 83.87 and 40.36 mg kg(-1), respectively. Lipid peroxidation increased after As exposure in all plants. However, the antioxidant enzyme activity and molecules concentration also increased which helped the plants to overcome As-induced oxidative stress. The study indicates that P. karka and C. dentata could be considered as As-accumulators and find application for As-phytoextraction in field conditions.

Wild Halophytic Phragmites karka Biomass Saccharification by Bacterial Enzyme Cocktail.

Biofuel derived from halophytic biomass is getting attention owing to the concerns of energy versus food crisis. The disadvantages associated with edible bioenergy resources necessitate the need to explore new feedstocks for sustainable biofuel production. In this study, biomass from locally available abundant halophytes (Panicum antidotale, Phragmites karka, Halopyrum mucronatum, and Desmostachya bipinnata) was screened for saccharification by an enzyme cocktail composed of cellulase, xylanase, and pectinase from Brevibacillus borstelensis UE10 and UE27, Bacillus aestuarii UE25, Aneurinibacillus thermoaerophilus UE1, and Bacillus vallismortis MH 1. Two types of pretreatment, i.e., with dilute acid and freeze-thaw, were independently applied to the halophytic biomass. Saccharification of acid-pretreated P. karka biomass yielded maximum reducing sugars (9 mg g-1) as compared to other plants. Thus, the factors (temperature, pH, substrate concentration, and enzyme units) affecting its saccharification were optimized using central composite design. This statistical model predicted 49.8 mg g-1 of reducing sugars that was comparable to the experimental value (40 mg g-1). Scanning electron microscopy and Fourier-transform infrared spectroscopy showed significant structural changes after pretreatment and saccharification. Therefore, halophytes growing in saline, arid, and semi-arid regions can be promising alternative sources for bioenergy production.

Taxonomic description and draft genome of Pseudomonas sediminis sp. nov., isolated from the rhizospheric sediment of Phragmites karka.

The taxonomic position of a Gram-stain-negative, rod-shaped bacterial strain, designated PI11T, isolated from the rhizospheric sediment of Phragmites karka was characterized using a polyphasic approach. Strain PI11T could grow optimally at 1.0% NaCl concentration with pH 7.0 at 30°C and was positive for oxidase and catalase but negative for hydrolysis of starch, casein, and esculin ferric citrate. Phylogenetic analysis of 16S rRNA gene sequences indicated that the strain PI11T belonged to the genus Pseudomonas sharing the highest sequence similarities with Pseudomonas indoloxydans JCM 14246T (99.72%), followed by, Pseudomonas oleovorans subsp. oleovorans DSM 1045T (99.29%), Pseudomonas toyotomiensis JCM 15604T (99.15%), Pseudomonas chengduensis DSM 26382T (99.08%), Pseudomonas oleovorans subsp. lubricantis DSM 21016T (99.08%), and Pseudomonas alcaliphila JCM 10630T (99.01%). Experimental DNA-DNA relatedness between strain PI11T and P. indoloxydans JCM 14246T was 49.4%. The draft genome of strain PI11T consisted of 4,884,839 bp. Average nucleotide identity between the genome of strain PI11T and other closely related type strains ranged between 77.25-90.74%. The polar lipid pattern comprised of phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylcholine. The major (> 10%) cellular fatty acids were C18:1ω6c/ω7c, C16:1ω6c/ω7c, and C16:0. The DNA G + C content of strain PI11T was 62.4 mol%. Based on the results of polyphasic analysis, strain PI11T was delineated from other closely related type strains. It is proposed that strain PI11T represents represents a novel species of the genus Pseudomonas, for which the name Pseudomonas sediminis sp. nov. is proposed. The type strain is PI11T (= KCTC 42576T = DSMZ 100245T).

Ethnopharmacological investigation of the aerial part of Phragmites karka (Poaceae).

BACKGROUND: In this ethnopharmacological study, methanolic extract of the aerial plant parts of Phragmites karka (Family: Poaceae) and its petroleum ether and carbon tetrachloride fractions were investigated for bioactivities in Swiss-albino mice, namely, analgesic, central nervous system (CNS) depressant, hypoglycemic, and antidiarrheal activity. METHODS: The cold methanolic extract of the aerial plant parts of Phragmites karka (MEPK) was first prepared, and it was then further fractionated as petroleum ether (PEFMEPK) and carbon tetrachloride (CTFMEPK) fractions. Analgesic activity was performed employing acidic acid-induced writhing test, central analgesic effect by radiant heat tail-flick method. CNS depressant activity was evaluated by phenobarbitone-induced sleeping time test. Hypoglycemic activity was tested by glucose tolerance test (GTT). Antidiarrheal activity was evaluated by castor oil-induced diarrhea method. For all in vivo tests, doses of 200 and 400 mg/kg body weight were used. RESULTS: In the mice model, the MEPK, PEFMEPK, and CTFMEPK fractions showed significant peripheral analgesic activity at a dose of 400 mg/kg body weight with percentage of inhibition of acetic acid-induced writhing 77.67 (p<0.001), 33.50 (p<0.001), and 40.29 (p<0.001), respectively, compared to the standard dichlofenac (60.68%, p<0.001) group. The hypoglycemic properties of MEPK, PEFMEPK, and CTFMEPK extracts were evaluated in normoglycemic mice where the reduction of blood glucose level after 30 min of glucose load were 69.85%, 78.91%, and 72.73%, respectively, and for standard glibenclamide, the reduction was 72.85%. All results were significant (p<0.05). In the case of the CNS depressant activity by phenobarbitone-induced sleeping time test, the crude ME significantly reduced sleep latency by 57.14% and increased the duration of sleep by 63.29% compared to the control, which were comparable to that of standard diazepam (65.71% and 77.62%, respectively). Among all the extract and fractions, methanolic extract showed the maximum antidiarrheal effect. The methanolic extract at 200 mg/kg dose induced a significant decrease in the total number of defecation in 4 h (69.05% of inhibition, p<0.001) and at 400 mg/kg dose showed 76.19% of inhibition (p<0.001). CONCLUSIONS: In light of the available literature, these findings represent the first experimental investigation of biological activities of P. karka in the perspective of their traditional use.

Salinity and macrophyte drive the biogeography of the sedimentary bacterial communities in a brackish water tropical coastal lagoon.

Brackish water coastal lagoons are least understood with respect to the seasonal and temporal variability in their sedimentary bacterial communities. These coastal lagoons are characterized by the steep environmental gradient and provide an excellent model system to decipher the biotic and abiotic factors that determine the bacterial community structure over time and space. Using Illumina sequencing of the 16S rRNA genes from a total of 100 bulk surface sediments, we investigated the sedimentary bacterial communities, their spatiotemporal distribution, and compared them with the rhizosphere sediment communities of a common reed; Phragmites karka and a native seagrass species; Halodule uninervis in Chilika Lagoon. Spatiotemporal patterns in bacterial communities were linked to specific biotic factors (e.g., presence and type of macrophyte) and abiotic factors (e.g., salinity) that drove the community composition. Comparative assessment of communities highlighted bacterial lineages that were responsible for segregating the sediment communities over distinct salinity regimes, seasons, locations, and presence and type of macrophytes. Several bacterial taxa were specific to one of these ecological factors suggesting that species-sorting processes drive specific biogeographical patterns in the bacterial populations. Modeling of proteobacterial lineages against salinity gradient revealed that α- and γ-Proteobacteria increased with salinity, whereas ß-Proteobacteria displayed the opposite trend. The wide variety of biogeochemical functions performed by the rhizosphere microbiota of P. karka must be taken into consideration while formulating the management and conservation plan for this reed. Overall, this study provides a comprehensive understanding of the spatiotemporal dynamics and functionality of sedimentary bacterial communities and highlighted the role of biotic and abiotic factors in generating the biogeographical patterns in the bacterial communities of a tropical brackish water coastal lagoon.

The draft genome sequence of Mangrovibacter sp. strain MP23, an endophyte isolated from the roots of Phragmites karka.

Till date, only one draft genome has been reported within the genus Mangrovibacter. Here, we report the second draft genome shotgun sequence of a Mangrovibacter sp. strain MP23 that was isolated from the roots of Phargmites karka (P. karka), an invasive weed growing in the Chilika Lagoon, Odisha, India. Strain MP23 is a facultative anaerobic, nitrogen-fixing endophytic bacteria that grows optimally at 37 °C, 7.0 pH, and 1% NaCl concentration. The draft genome sequence of strain MP23 contains 4,947,475 bp with an estimated G + C content of 49.9% and total 4392 protein coding genes. The genome sequence has provided information on putative genes that code for proteins involved in oxidative stress, uptake of nutrients, and nitrogen fixation that might offer niche specific ecological fitness and explain the invasive success of P. karka in Chilika Lagoon. The draft genome sequence and annotation have been deposited at DDBJ/EMBL/GenBank under the accession number LYRP00000000.