Study on the performance of vertical flow constructed wetland microcosm with Canna sps. for treatment of high chromium-containing wastewater.

Chromium (Cr (VI)) pollution has plagued the environment due to chromite mining and various industrial actions. Constructed wetlands (CW) have emerged as a potential wastewater management technique that utilizes physical, chemical, and biological processes. The present study investigates the use of vertical flow-constructed wetlands (CW) using manure-rich garden soil and sand as substrates in planted CW (CW-P) and unplanted CW (CW-UP) to remove Cr (VI) from simulated wastewater. The experiment was performed in two phases, i.e., Phase I and II, in the same system. In Phase I, initial Cr (VI) concentrations were varied between 5 and 200 mg/l at a fixed hydraulic retention time (HRT) of 48 h, while in Phase II, the effect of HRT (24 h, 48 h, and 96 h) was studied at a fixed Cr (VI) concentration of 200 mg/L in the influent. At 24 h, HRT removal efficiencies were 90.20% for CW-P and 86.41% for CW-UP. However, at 96 h of HRT, the system showed nearly the same removal efficiency. Scanning electron microscopy with energy dispersion X-Ray spectroscopy analysis suggested the conversion of Cr (VI) to Cr (III) in soil precipitate and the translocation of Cr (VI) in plant tissues (Canna sps.). Moreover, microbial diversity profiling indicated that microbial diversity involved in pollutant removal differed in both systems. The phytotoxicity test clearly showed the decrease in toxicity level in the treated effluent, concluding the reusability of treated water. This exploratory study suggested that the CW can potentially remove a higher concentration of hexavalent chromium at longer HRT.

Heavy metals and nutrients removal in a batch-fed greywater treatment system planted with Canna indica and Oryza sativa L.

The objective of this investigation was to determine whether Canna indica and Oryza sativa L. plants have the phytoremediation potential for removing heavy metals and nutrients from greywater treated in batch-fed Horizontal sub-surface Flow Constructed Wetlands (HssFCW). The HssFCW had a Hydraulic Retention Time (HRT) and organic loading rate (OLR) of 3 days and 3.96 (g.BOD/m2.day) respectively. Greywater (GW) samples were characterized for electrical conductivity (EC), total nitrogen (TN), total phosphorous (TP), pH, sodium adsorption ratio (SAR), metals (Al, Fe, Mg, Ca) and Biochemical Oxygen Demand (BOD5). The accumulation of metals in the soil and edible parts of plants was evaluated in terms of bioconcentration and translocation factors. Metal concentrations were determined using an atomic absorption spectrometer, while nutrients were by colorimetric method. The result shows that the metals and nutrients were below the WHO allowable limit for treated greywater recycling in agriculture. Nutrient removal was insignificantly different while metal removal was significantly different in the constructed wetlands (CW). The results indicated that C. indica is preferred as a perennial plant with unlimited metal accumulation and high nutrient removals compare to O. sativa L. with a high metal concentration in the above-ground plant tissue and also an annual plant.

Performance of Canna Indica based microscale vertical flow constructed wetland under tropical conditions for domestic wastewater treatment.

Constructed wetlands (CWs) have great potential as low-cost natural wastewater treatment in developing countries. The present study appraises the performance of the vertical flow constructed wetland for domestic wastewater treatment. More specifically, the potential of Canna Indica in the removal of carbon, nitrogen, and phosphorus (CNP) from wastewater under tropical conditions. CW cell was fabricated with a vegetative layer of Canna Indica and tested with domestic wastewater. Based on the test results, Canna Indica shows a high Removal Efficiency (RE) of Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5) on the order of 87% and 91%, respectively. Similarly, nutrients removal efficiency for total nitrogen (TN), total phosphorus (TP) was found to be 97% and 98%, respectively. The investigation also revealed that there is considerable removal of sulfates with efficiency equal to 78.4%. Overall, the Canna Indica based CWs were found to be suitable for wastewater treatment in the tropical regions, provided a viable medium for treating the wastewater in peri-urban and rural areas of developing countries.

This study investigates the performance of Canna indica based vertical flow wetlands for greywater treatment. The study investigates the results at different hydraulic retention times and loading rates.There are no much studies reporting the performance of this variety of plant species under a tropical humid climate.The results from the study can encourage adoption of this plant variety, indigenous to this part of the country, for wastewater treatmentHighlightsIt could emphasize the importance of familiarity with constructed wetlands to comprehend the RE of various climatic zones.It is possible to highlight the Canna-based CW's efficiency in removing organics and nutrients from domestic wastewater.The possibility for field-scale Canna-based CW to remove pollution in tropical climates was investigated, andDecentralization of wastewater treatment at the household level to apply CWs that will improve wastewater quality.

GC-MS Analysis of Bioactive Compounds in Ethanolic Leaf Extract of Hellenia speciosa (J.Koenig) S.R. Dutta.

Hellenia speciosa (J.Koenig) S.R. Dutta is a plant species belonging to the family Costaceae. It is widely distributed in China, India, Malaysia, Indonesia, tropical, and subtropical Asia. In Ayurveda, the rhizome of this plant has been extensively used to treat fever, rash, asthma, bronchitis, and intestinal worms. The objective of the present study was to investigate the phytochemical constituents of the leaf of Hellenia speciosa using gas chromatography and mass spectroscopy analysis (GC-MS). The GC-MS analysis revealed the presence of 17 phytochemical components in the ethanolic leaf extract of Hellenia speciosa. The prevailing bioactive compounds present in Hellenia speciosa were thymol (RT-10.019; 3.59%), caryophyllene (RT-11.854; 0.62%), caryophyllene oxide (RT-13.919; 1.34%), artumerone (RT-14.795; 1.35%), hexadecanoic acid methyl ester (RT-17.536; 2.77%), 9,12-octadecanoic acid methyl ester (RT-19.163; 1.35%), squalene (RT-24.980; 1.19%), piperine (RT-25.745; 3.11%), beta tocopherol (RT-26.681; 2.88%), vitamin E (RT-27.290; 2.64%), progesterone (RT-29.608; 3.18%), caparratriene (RT-29.861; 9.72%), and testosterone (RT-30.73; 5.81%). The compounds were identified by comparing their retention time and peak area with that of the literature and by interpretation of mass spectra. The results and findings of the present study suggest that the plant leaf can be used as a valuable source in the field of herbal drug discovery. The presence of bioactive compounds justifies the use of plant leaves for treating various diseases with fewer side effects and recommended the plant of pharmaceutical importance. However, further studies are needed to undertake its bioactivity and toxicity profile.

Comparison of heavy metal and nutrients removal in Canna indica and Oryza sativa L. based constructed wetlands for piggery effluent treatment in north-central Nigeria.

Batch-fed horizontal sub-surface flow constructed wetlands (HssFCW) were developed to compare the potential of Canna indica and Oryza sativa L. in removing heavy metals and nutrients from piggery effluent. Piggery effluent samples were characterized for nutrients (N and P) and metals (Mg, Al, Ca and Fe) before and after introducing them to the HssFCW with hydraulic retention time (HRT) of 3 days and operational flowrate of 0.014 m3/day. Three sets of constructed wetlands (CWs) were monitored during the dry season for 3 months. The bioconcentration factor (BCF) and translocation factor (TF) for the plants were evaluated. The results were all significantly different at p ≤ 0.05. O. sativa L removes more nutrients and metals than C. indica. The BCF for O. sativa L. was higher than for C. indica, while the TF for C. indica was higher for O. sativa L., indicating a higher metal translocation potential. Use of C. indica, a non-food crop, poses no health risks in HssFCWs whereas the grains of O. sativa L. are consumed directly by humans, presenting potential risks when used in HssFCWs. Compared to an annual O. sativa L., the perennial C. indica can be grown continuously in CWs for the phytoremediation of piggery effluent. Novelty statementNo known work about the phytoremediation potential of the two studied macrophytes in the agro-ecological zone is known. The study also provides insight into the bioconcentration of metals in the edible part of Oryza sativa L. FARO 44 (SIPI 692033).The characterization of piggery effluent revealed that its compositions were above the allowable limit for reuse and recycling despite the adoption of low-water use intensive method.The study showed that Oryza sativa L accumulates more metals in the above-ground tissues than in its root and provide insight into its use as a phytoremediation plant in the study area.The footprint of pollutants and metals in Oryza sativa L makes a perennial C. indica more suitable than O. sativa L. in piggery effluent phytoremediation.

Inhibitory effect of lignin from Canna edulis Ker residues on trypsin: kinetics and molecular docking studies.

BACKGROUND: Lignin extracted from Canna edulis Ker residues shows a strong inhibitory effect on α-glucosidase and a promoting effect on α-amylase. Protease activity inhibition may play a key role in disease processes, such as metastasis, tumor invasion and bacterial colonization. Hence, in the present study, the inhibitory mechanism of lignin on trypsin was examined, including the interaction type, thermodynamic parameters, structure, reaction site and molecular docking. RESULTS: The isolated lignin presented an inhibitory effect on trypsin activity with an IC50 value of 1.35 µmol L-1 . This inhibition was a mixed linear type with a constant Ki of 3.92 µmol L-1 . The lignin could bind with the key amino acid residue Ser195 on the active site of the trypsin molecule to inhibit its activity, and the phenolic hydroxyl group and -OH on the ß-O-4 structure of the lignin molecule were the major groups bound with trypsin. CONCLUSION: These results illustrate the inhibitory effects of Canna edulis residue lignin on protease, which helps with respect to understanding the possible application of lignin in the food industry in functional foods. © 2020 Society of Chemical Industry.

Antifungal activity of extracts and purified saponins from the rhizomes of Chamaecostus cuspidatus against Candida and Trichophyton species.

AIM: To evaluate the antifungal activity of extracts of Chamaecostus cuspidatus against Candida and Trichophyton species. METHODS AND RESULTS: Crude ethanol extracts of leaves, stems and rhizomes were prepared and evaluated for antimicrobial activity. Only the rhizomes extract (RE) showed antifungal activity but had no inhibitory effect against bacteria (Staphylococcus aureus and Escherichia coli). The RE was then submitted to liquid-liquid partition with hexane (Hex), dichloromethane, chloroform, ethyl acetate and water. The Hex fraction (Hex Fr) from the RE was found to have the best antifungal effect. Three known saponins were isolated from the Hex Fr, of which two (dioscin and aferoside A) showed good antifungal activity. In addition, Hex Fr and the two bioactive compounds had no antibacterial effect, but exhibited fungicidal activity, caused significant changes in the morphology of the fungal cells and showed anti-Candida albicans biofilm activity. Finally, the bioactive plant products presented greater selectivity for fungal cells over normal human cells. CONCLUSIONS: The rhizomes of C. cuspidatus have bioactive saponins that function as effective antifungals against Candida and Trichophyton species, and have antibiofilm activity against C. albicans. SIGNIFICANCE AND IMPACT OF THE STUDY: Chamaecostus cuspidatus REs may have potential clinical application towards the management of superficial mycoses caused by Candida and Trichophyton species.

In vitro and in vivo Antibacterial Activity of Cheilocostus speciosus Rhizome Extract on Resistant Bacteria.

BACKGROUND AND OBJECTIVE: Cheilocostus speciosus has traditionally been used in alternative medicine for different therapeutic purposes in different countries, including as an anti-infective agent. Antimicrobial properties of C. speciosus against standard bacterial strains have been reported before, however, complementary in vivo investigations, as well as, its antimicrobial activity against multi drug-resistant (MDR) bacteria are insufficient, if not lacking. In our study, in vitro and in vivo methods were used to test its antimicrobial activities on prominent clinical MDR isolates. MATERIALS AND METHODS: Cheilocostus speciosus rhizome extracts (CSRE) were prepared using different solvents; methanol, hexane, petroleum ether, ethylene glycol and water. The bactericidal activity of CSRE was tested on methicillin resistant S. aureus (MRSA), A. baumannii, K. pneumoniae serotype K2 (Kp K2), MDR P. aeruginosa, S. typhimurium and MDR E. coli. The standard disc diffusion and the broth micro-dilution methods were used to confirm the efficacy of CSRE against the tested microorganisms. In vitro results proved a potent bactericidal effect on MRSA and Kp K2 and a pronounced bacteriostatic effect against E. coli. RESULTS: We further confirmed the antibacterial activity of CSRE using BALB/c mice, animals were infected with Kp K2 or MRSA along with their standard strains; the extract was found to significantly reduce the bacterial load in mice lungs, liver and spleen. In addition, extracts were found to be more effective on the MDRs than the standard strains. CONCLUSION: It is concluded that CSRE could be a potential source for new antibiotics, further investigations are required to identify the bioactive components.

A specific gut microbiota and metabolomic profiles shifts related to antidiabetic action: The similar and complementary antidiabetic properties of type 3 resistant starch from Canna edulis and metformin.

The relationship between gut microbiota and type 2 diabetes mellitus (T2DM) has drawn increasing attention, and the benefits of various treatment strategies, including nutrition, medication and physical exercise, maybe microbially-mediated. Metformin is a widely used hypoglycemic agent, while resistant starch (RS) is a novel dietary fiber that emerges as a nutritional strategy for metabolic disease. However, it remains unclear as to the potential degree and interactions among gut microbial communities, metabolic landscape, and the anti-diabetic effects of metformin and RS, especially for a novel type 3 resistant starch from Canna edulis (Ce-RS3). In the present study, T2DM rats were administered metformin or Ce-RS3, and the changes in gut microbiota and serum metabolic profiles were characterized using 16S-rRNA gene sequencing and metabolomics, respectively. After 11 weeks of treatment, Ce-RS3 exhibited similar anti-diabetic effects to those of metformin, including dramatically reducing blood glucose, ameliorating the response to insulin resistance and glucose tolerance test, and relieving the pathological damage in T2DM rats. Interestingly, the microbial and systemic metabolic dysbiosis in T2DM rats was effectively modulated by both Ce-RS3 and, to a lesser extent, metformin. The two treatments increased the gut bacterial diversity, and supported the restoration of SCFA-producing bacteria, thereby significantly increasing SCFAs levels. Both treatments simultaneously corrected 16 abnormal metabolites in the metabolism of lipids and amino acids, many of which are microbiome-related. PICRUSt analysis and correlation of SCFAs levels with metabolomics data revealed a strong association between gut microbial and host metabolic changes. Strikingly, Ce-RS3 exhibited better efficacy in increasing gut microbiota diversity with a peculiar enrichment of Prevotella genera. The gut microbial properties of Ce-RS3 were tightly associated with the T2DM-related indexes, showing the potential to alleviate diabetic phenotype dysbioses, and possibly explaining the greater efficiency in improving metabolic control. The beneficial effects of Ce-RS3 and metformin might derive from changes in gut microbiota through altering host-microbiota interactions with impact on the host metabolome. Given the complementarity of Ce-RS3 and metformin in regulation of gut microbiota and metabolites, this study also prompted us to suggest possible "Drug-Dietary fiber" combinations for managing T2DM.

Efficacy of zerumbone against dual-species biofilms of Candida albicans and Staphylococcus aureus.

Candida albicans and Staphylococcus aureus are the most common opportunistic pathogens that co-exist as mixed biofilms. Dual-species biofilms of C. albicans and S. aureus cause nosocomial medical device-related infections that are strongly resistant to antibiotics and host immune responses compared with mono-species biofilms. The purpose of this study was to describe the efficacy of zerumbone derived from Zingiber zerumbet (L.) Smith, on dual-species biofilm formation. This study examined the inhibitory effects of zerumbone on planktonic cell growth, adhesion and biofilm formation. The results demonstrated that zerumbone remarkably inhibited mono- and dual-species biofilms formed by C. albicans and S. aureus using the XTT [2,3-bis(2-smethoxy-4-nitro-5-sulfo-phenyl)-2H-tetrazolium-5-carboxanilide]-reduction assay. Furthermore, a significant decrease in biomass and cell density of dual-species biofilms following zerumbone treatment was confirmed using confocal laser scanning microscopy (CLSM). Therefore, our study suggests that zerumbone is a potential antimicrobial and antibiofilm agent indicated for the therapeutic management of nosocomial medical device-related infections induced by dual-species biofilms of C. albicans and S. aureus.

Effects of layered combined substrates on plant growth and treatment performance and its spatiotemporal variation of vertical-flow constructed wetlands.

Layered combined bio-ceramic, zeolite, and anthracite were used as substrates in vertical-flow constructed wetlands (VFCWs) for enhancing contaminant removal from synthetic municipal wastewater. Plant growth and propagation and the removal of organic matter, nitrogen, and phosphorus as well as its spatiotemporal variation were evaluated systematically. The results demonstrated that three different substrates were adequate for the establishment of Canna indica L., especially for zeolite. All small-scale VFCW units were simultaneous efficient in removing CODCr (73.9-78.7%), NH4+-N (83.8-89.9%), TN (88.3-91.5%), SRP (93.8-98.6%), and TP (87.1-90.9%) with a little significant difference on treatment performance. Different pollution removal processes followed a different trend because of their different removal mechanisms driven by the synergy of substrate, plant, and microorganism. Purification space moved down due to the adsorption capacity consumption of upper layer substrate over time. It was concluded that VFCWs filled with layered combined bio-ceramic, zeolite, and anthracite had great potential for treating municipal wastewater.

Allelopathic Effects on Microcystis aeruginosa and Allelochemical Identification in the Cuture Solutions of Typical Artificial Floating-Bed Plants.

Cyperus alternifolius (C. alternifolius) and Canna generalis (C. generalis) are widely used as artificial floating-bed (AFB) plants for water pollution control. This study evaluated the release of anti-cyanobacterial allelochemicals from both plants in AFB systems. A series of cyanobacterial assays using pure culture solutions and extracts of culture solutions of C. alternifolius and C. generalis demonstrated allelopathic growth inhibition of a cyanobacterium M. aeruginosa. After 45 days of incubation by the culture solutions, both final inhibitory rates of M. aeruginosa were more than 99.6% compared with that of the control groups. GC/MS analyses indicated the presence of a total of 15 kinds of compounds, including fatty acids and phenolic compounds, in both plants' culture solutions, which are are anti-cyanobacterial. These findings provide a basis to apply artificial floating-bed plants for cyanobacterial inhibition using allelopathic effects.

Chemopreventive Effects of Edible Canna (Canna edulis Kerr.) Against Colorectal Carcinogenesis: Effects on Expression of Adenomatous Polyposis Coli and Inducible Nitric Oxide Synthase in Rat Inflammatory Model

Objective: Dietary high fibre and calcium intake has been suggested to reduce colorectal cancer risk. However, there is limited information available regarding the potential of edible canna (Ganyong), with high dietary fibre and calcium content, to act as a preventive agent for colorectal cancer. This experimental study was conducted to investigate the preventive effect of Ganyong in reducing colorectal carcinogenesis with attention to effects on adenomatous polyposis coli (APC) and inducible nitric oxide synthase (iNOS) expression. Methods: Thirty male Wistar rats were divided into 5 equal groups; a normal control group without azoxymethane/dextran sodium sulphate (AOM/DSS) induction and Ganyong, a 'cancer' control group with AOM/DSS induction only, and three treatment groups with AOM/DSS induction and different percentages (5%, 10% and 20%) of Ganyong. Paraffin-embedded sections of rat colon tissue were analysed by haematoxylin-eosin and immunohistochemical staining against antibodies against APC and iNOS. Variation in rates of APC and iNOS expression were analyzed using the Kruskal-Wallis test followed by the Dunn's test (SPSS statistic version 24). P<0.05 was considered statistically significant. Results: AOM/DSS induction increased the expression of APC (p=0.013) and iNOS (p=0.013) compared to the normal control group. APC expression in the treated groups was lower than in the 'cancer' control group (p=0.049), especially in the 10% Ganyong group (p=0.02). In contrast, there was no significant variation among the treated groups regarding iNOS expression. Histopathological features of the colon supported the data for APC and iNOS expression. Conclusion: This study indicated potential chemopreventive effects of Ganyong reducing expression of factors contributing to colorectal carcinogenesis.

Influence of vegetation type and temperature on the performance of constructed wetlands for nutrient removal.

In this study, the influence of vegetation type and environmental temperature on performance of constructed wetlands (CWs) was investigated. Results of vegetation types indicated that the removal of most nutrients in polyculture was greater than those in monoculture and unplanted control. The greatest removal percentages of NH4+-N, total nitrogen (TN) and total phosphorus (TP) in polyculture were 98.7%, 98.5%, and 92.6%, respectively. In experiments of different temperatures, the removal percentages of NH4+-N, NO3--N, TN and TP in all CWs tended to decrease with the decline of temperature. Especially, a sharp decline in the removal percentages of NO3--N (decreased by above 13.8%) and TN (decreased by above 7.9%) of all CWs was observed at low temperature (average temperature of 8.9 °C). Overall, the performance of CWs was obviously influenced by temperature, and the polyculture still showed best performance in the removal of nitrogen when the average temperature dropped to 19.8 °C. Additionally, the variations of urease activities in rhizosphere soil tended to decrease with the decreasing temperature. Overall, a substantial enhancement for nitrogen and TP removal in polyculture (Canna indica + Lythrum salicaria) was observed. In conclusion, CW cultivated with polyculture was a good strategy for enhancing nutrient removal when temperature was above 19.8 °C.

Zingiberis Siccatum Rhizoma, the active component of the Kampo formula Daikenchuto, induces anti-inflammatory actions through α7 nicotinic acetylcholine receptor activation.

BACKGROUND: We previously reported that Daikenchuto (DKT), a gastrointestinal prokinetic Japanese herbal (Kampo) medicine used for the treatment of postoperative ileus (POI), has characteristic potent anti-inflammatory activity. This effect may be partly mediated by the activation of α7 nicotinic acetylcholine receptor (nAChR). In this study, we identified the specific herbs in DKT that induce anti-inflammatory action. METHODS: The herbal components of DKT were individually administered orally to each mouse four times before and after intestinal manipulation (IM) was carried out on the distal ileum. The anti-inflammatory activity of each crude drug was subsequently evaluated using immunohistochemical analyses of relevant molecules. KEY RESULTS: Treatment with Zingiberis Siccatum Rhizoma (ZSR) but not the other components inhibited the infiltration of cluster of differentiation 68 (CD68)-positive macrophages as effectively as DKT treatment. Selective α7nAChR antagonists, such as methyllycaconitine citrate, or transient receptor potential ankyrin 1 (TRPA1) antagonists, such as HC-030031, significantly inhibited the amelioration of macrophage infiltration by ZSR. The inhibition of macrophage infiltration by ZSR was abolished in both α7nAChR and 5-hydroxytryptamine 4 receptor (5-HT4 R) knockout mice. CONCLUSIONS & INFERENCES: Daikenchuto-induced anti-inflammatory activity, which was mediated by inhibiting macrophage infiltration in POI, is dependent on the effects of ZSR. Zingiberis Siccatum Rhizoma activates TRPA1 channels possibly in enterochromaffin (EC) cells to release 5-HT, which stimulates 5-HT4 R in the myenteric plexus neurons to release ACh, which in turn activates α7nAChR on macrophages to inhibit inflammation in POI.

Effectiveness of Vegetated Drainage Ditches for Domestic Sewage Effluent Mitigation.

Plant species have an important role in eco-ditches; however, the Michaelis-Menten kinetic parameters of nutrient uptake, growth rate and purification efficiency of ditch plants and their influences on domestic sewage treatment efficiency are still unclear. Growth rates of all nine species, but especially Lemna gibba, Cladophora and Myriophyllum verticillatum were best in undiluted domestic sewage as opposed to a mixture of domestic sewage. Performance of species to accumulate nutrients was not only species-specific, but was also affected by both sewage treatments. Removal efficiency of nutrients was dependent on both plant species and treatment. Uptake kinetic parameters were significantly affected by both nutrient form and plant species. The maximum uptake rate (Vmax) of NH4-N was higher than NO3-N. Similarly, Km values for NH4-N were greater than NO3-N. These results could be used to identify plants for sewage treatment efficiency and enhance water quality in eco-ditch treatment systems.

Canna edulis Leaf Extract-Mediated Preparation of Stabilized Silver Nanoparticles: Characterization, Antimicrobial Activity, and Toxicity Studies.

A novel approach to synthesize silver nanoparticles (AgNPs) using leaf extract of Canna edulis Ker-Gawl. (CELE) under ambient conditions is reported here. The as-prepared AgNPs were analyzed by UV-visible spectroscopy, transmission emission microscopy, X-ray diffraction, Fourier transform-infrared spectroscopy, energy-dispersive analysis of X-ray spectroscopy, zeta potential, and dynamic light scattering. The AgNPs showed excellent antimicrobial activity against various pathogens, including bacteria and various fungi. The biocompatibility of the AgNPs was analyzed in the L929 cell line using NRU and MTT assays. Acridine orange/ethidium bromide staining was used to determine whether the AgNPs had necrotic or apoptotic effects on L929 cells. The concentration of AgNPs required for 50% inhibition of growth of mammalian cells is far more than that required for inhibition of pathogenic microorganisms. Thus, CELE is a candidate for the eco-friendly, clean, cost-effective, and nontoxic synthesis of AgNPs.

Pyrolysis of wetland biomass waste: Potential for carbon sequestration and water remediation.

Management of biomass waste is crucial to the efficiency and sustainable operation of constructed wetlands. In this study, biochars were prepared using the biomass of 22 plant species from constructed wetlands and characterized by BET-N2 surface area analysis, FTIR, TGA, SEM, EDS, and elemental compositions analysis. Biochar yields ranged from 32.78 to 49.02%, with mesopores dominating the pore structure of most biochars. The biochars had a R50 recalcitrance index of class C and the carbon sequestration potential of 19.4-28%. The aquatic plant biomass from all the Chinese constructed wetlands if made into biochars has the potential to sequester 11.48 Mt carbon yr(-1) in soils over long time periods, which could offset 0.4% of annual CO2 emissions from fossil fuel combustion in China. In terms of adsorption capacity for selected pollutants, biochar derived from Canna indica plant had the greatest adsorption capacity for Cd(2+) (98.55 mg g(-1)) and NH4(+) (7.71 mg g(-1)). Whereas for PO4(3-), Hydrocotyle verticillata derived biochar showed the greatest adsorption capacities (2.91 mg g(-1)). The results from this present study demonstrated that wetland plants are valuable feedstocks for producing biochars with potential application for carbon sequestration and contaminant removal in water remediation.

Organogenesis and Ultrastructural Features of In Vitro Grown Canna indica L.

An efficient protocol for micropropagation of Canna indica L., an economically and pharmaceutically important plant, was standardized using rhizome explants, excised from two-month-old aseptic seedlings. Complete plant regeneration was induced on MS medium supplemented with 3.0 mg/L BAP plus 1.5 mg/L NAA, which produced the highest number of shoots (73.3 ± 0.5%) and roots (86.7 ± 0.4%) after 2 weeks. Furthermore, the optimum media for multiple shoots regeneration were recorded on MS enriched with 7.0 mg/L BAP (33.0 ± 0.5%). Plantlets obtained were transplanted to pots after two months and acclimatized in the greenhouse, with 75% survival. In addition, ultrastructural studies showed that rhizomes of in vitro grown specimens were underdeveloped compared to the in vivo specimens, possibly due to the presence of wide spaces. Meanwhile, the leaves of in vivo specimens had more open stomata compared to in vitro specimens, yet their paracytic stomata structures were similar. Hence, there were no abnormalities or major differences between in vitro regenerants and mother plants.