Phosphate solubilizing Aspergillus Niger PH1 ameliorates growth and alleviates lead stress in maize through improved photosynthetic and antioxidant response.

Among the several threats to humanity by anthropogenic activities, contamination of the environment by heavy metals is of great concern. Upon entry into the food chain, these metals cause serious hazards to plants and other organisms including humans. Use of microbes for bioremediation of the soil and stress mitigation in plants are among the preferred strategies to provide an efficient, cost-effective, eco-friendly solution of the problem. The current investigation is an attempt in this direction where fungal strain PH1 was isolated from the rhizosphere of Parthenium hysterophorus which was identified as Aspergillus niger by sequence homology of the ITS 1 and ITS 4 regions of the rRNA. The strain was tested for its effect on growth and biochemical parameters as reflection of its potential to mitigate Pb stress in Zea mays exposed to 100, 200 and 500 µg of Pb/g of soil. In the initial screening, it was revealed that the strain has the ability to tolerate lead stress, solubilize insoluble phosphate and produce plant growth promoting hormones (IAA and SA) and other metabolites like phenolics, flavonoids, sugar, protein and lipids. Under 500 µg of Pb/g of soil, Z. mays exhibited significant growth retardation with a reduction of 31% in root length, 30.5% in shoot length, 57.5% in fresh weight and 45.2% in dry weight as compared to control plants. Inoculation of A. niger to Pb treated plants not only restored root and shoot length, rather promoted it to a level significantly higher than the control plants. Association of the strain modulated the physio-hormonal attributes of maize plants that resulted in their better growth which indicated a state of low stress. Additionally, the strain boosted the antioxidant defence system of the maize there by causing a significant reduction in the ascorbic acid peroxidase (1.5%), catalase (19%) and 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical scavenging activity (33.3%), indicating a lower stress condition as compared to their non-inoculated stressed plants. Based on current evidence, this strain can potentially be used as a biofertilizer for Pb-contaminated sites where it will improve overall plant health with the hope of achieving better biological and agricultural yields.

Functional characterization of complete and immunodominant epitopes of a novel pollen allergen from Parthenium hysterophorus.

Summary: Background. Parthenium hysterophorus pollen induces chronic clinical conditions such as allergic rhinitis and bronchial asthma. Among the plethora of proteins in the pollens, only few were reported to induce allergy. Currently sensitization to P. hysterophorus pollen allergen is diagnosed by skin prick test (SPT) using the entire pollen extract instead of using the specific allergen. Methods. In P. hysterophorus sensitized patients, SPT was done using the crude pollen extract, 40 kDa allergenic pollen protein and two commercially synthesized allergen epitopes (17 and 24) of P. hysterophorus. Dot-blot of allergen epitopes was done using P. hysterophorus sensitized sera. Crude pollen extract (1, 1.25, 2.5, 5 and 10 µg/mL), 40 kDa allergenic protein (3 µg/mL), and allergen epitopes (3µg/mL) were used to perform Basophil Activation Test (BAT). Results. Crude pollen extract at 2.5, 5, 10 µg/mL and 40 kDa allergenic protein at 3µg/mL concentrations induced wheal and flare reaction by around 15 minutes, whereas commercially synthesized allergen epitopes at 3µg/mL induced wheal and flare reactions in less than 10 minutes. Allergen epitopes (3 µg/mL) revealed strong reactivity with sensitized patient's IgE in dot-blot analysis. Basophil activation Test using crude pollen extract (2.5, 5, 10 µg/mL), 40 kDa allergenic protein (3 µg/mL), and allergenic epitopes (3µg/mL) indicated significant basophil activation (as measured by CD63 expression) in sensitized patients. Conclusions. The 40 kDa allergenic protein and its allergenic epitopes (17 and 24) induced phenotypic and cellular immune responses in P. hysterophorus sensitized individuals. The tested allergenic epitopes (17 and 24) induced faster wheal and flare reactions in comparison with the crude extract and the 40 kDa allergenic protein. The novel 40kDa allergenic protein and its allergen epitopes identified here may be useful for the development of component-resolved diagnosis (CRD) while also serving as a potential therapeutic lead for desensitization treatment for P. hysterophorus pollen induced allergy.

A Comparison between Bulgarian Tanacetum parthenium Essential Oil from Two Different Locations.

Tanacetum parthenium L. (Asteraceae) is a perennial herbaceous plant with a long-standing historical use in traditional medicine. Recently Tanacetum parthenium L. essential oil has been associated with a promising potential for future applications in the pharmaceutical industry, in the cosmetics industry, and in agriculture. Investigations on the essential oil (EO) have indicated antimicrobial, antioxidant, and repellent activity. The present study aimed to evaluate the chemical composition of Bulgarian T. parthenium essential oil from two different regions, to compare the results to those reported previously in the literature, and to point out some of its future applications. The essential oils of the air-dried flowering aerial parts were obtained by hydrodistillation using a Clevenger-type apparatus. The chemical composition was evaluated using gas chromatography with mass spectrometry (GC-MS). It was established that the oxygenated monoterpenes were the predominant terpene class, followed by the monoterpene hydrocarbons. Significant qualitative and quantitative differences between both samples were revealed. Camphor (50.90%), camphene (16.12%), and bornyl acetate (6.05%) were the major constituents in the feverfew EO from the western Rhodope Mountains, while in the EO from the central Balkan mountains camphor (45.54%), trans-chrysanthenyl acetate (13.87%), and camphene (13.03%) were the most abundant components.

Impact of feeding biochar sources in rohu (Labeo rohita): Evaluating the growth, nutrient absorption, carcass composition, haematology and mineral status.

Biochar, an organic carbonaceous matter, is a unique feed additive that is now being used in aquaculture industry to formulate a cost-effective and eco-friendly diet. This experiment (in door) was conducted over course of 90 days to determine the most effective form of biochar, produced from various sources, for supplementation in Moringa oleifera seed meal-based diet. These sources were: farmyard manure biochar, parthenium biochar (PB), vegetable waste biochar, poultry waste biochar (PWB) and corncob waste biochar, added at 2 g/kg concentration to determine the effect of supplementation on the growth indices, nutrient absorption, carcass composition, haematology and mineral status of Labeo rohita (rohu) fingerlings. The research design consisted of six test diets with three replications (6 × 3) of each. Total of 270 fingerlings (6.30 ± 0.020 g) were fed at 5% body weight and 15 of them were kept in separate steel tanks. The results indicated that PWB was most effective in improving weight gain (285.58 ± 4.54%) and feed conversion ratio (1.060 ± 0.040) compared to control diet and other test diets. The same type of biochar (PWB) produced the best results for nutrient digestibility, that is, crude protein, crude fat and gross energy and carcass composition. In terms of haematology and mineral status, PWB showed the best results. In conclusion, it was found that PWB significantly enhanced (p < 0.05) L. rohita fingerling's growth, carcass composition, nutrient digestibility, haematological parameters (red blood cells, white blood cells, platelets and haemoglobin) and mineral composition (Ca, Na, P, Mg, Fe, Mn, Zn, K and Cu) whereas PB negatively affected all parameters. It is anticipated that the potential use of biochar will increase in aquaculture industry, as research on its incorporation in fish feeds is still limited.

Development of metal free carbon catalyst derived from Parthenium hysterophorus for the electrochemical detection of dopamine.

Parthenium hysterophorus, one of the seven most hazardous weeds is widely known for its allergic, respiratory and skin-related disorders. It is also known to affect biodiversity and ecology. For eradication of the weed, its effective utilization for the successful synthesis of carbon-based nanomaterial is a potent management strategy. In this study, reduced graphene oxide (rGO) was synthesized from weed leaf extract through a hydrothermal-assisted carbonization method. The crystallinity and geometry of the as-synthesized nanostructure are confirmed from the X-ray diffraction study, while the chemical architecture of the nanomaterial is ascertained through X-ray photoelectron spectroscopy. The stacking of flat graphene-like layers with a size range of ∼200-300 nm is visualized through high-resolution transmission electron microscopy images. Further, the as-synthesized carbon nanomaterial is advanced as an effective and highly sensitive electrochemical biosensor for dopamine, a vital neurotransmitter of the human brain. Nanomaterial oxidizes dopamine at a much lower potential (0.13 V) than other metal-based nanocomposites. Moreover, the obtained sensitivity (13.75 and 3.31 µA µM-1 cm-2), detection limit (0.6 and 0.8 µM), the limit of quantification (2.2 and 2.7 µM) and reproducibility calculated through cyclic voltammetry/differential pulse voltammetry respectively outcompete many metal-based nanocomposites that were previously used for the sensing of dopamine. This study boosts the research on the metal-free carbon-based nanomaterial derived from waste plant biomass.

Exploring invasive weed biochar as soil amendment: A study on fodder oats productivity and soil biological properties.

Biochar is known for the improvement of soil health, fertility, crop productivity, and quality in many agro-ecosystems globally, but information regarding fodder yield, quality, and soil microbial activity responses to biochar application remains very limited. The objective of this study was to prepare biochar from invasive weeds, i.e., Parthenium hysterophorus L. and Lantana camara L., and use it as a soil amendment along with inorganic fertilizers for oats (Avena sativa L.) growth, fodder yield, quality, and soil microbial activities in a two-year pot experiment. Treatments were comprised of control, 100% RDF (Recommended dose of fertilizers), 75% RDF along with three doses (2.5, 5.0, and 10 t/ha) of Parthenium hysterophorus L. biochar (PB) and Lantana camara L. biochar (LB), PB (10 t/ha), and LB (10 t/ha). Results showed that application of 75% RDF along with 10 t/ha LB gave significantly higher green (∼8%) and dry (∼7.8%) fodder yield and crude protein (∼6%) and decreased acid detergent fibre (ADF) and neutral detergent fibre (NDF) by 5.70 and 6.04% as compared to the 100% RDF treatment. The same treatment had a significantly higher population of bacteria (7.33 × 108 colony forming unit (CFU)/g soil), alkaline phosphatase activity (19.56 µg pNP/g soil/h), microbial biomass carbon (156.67 µg/g soil) and dehydrogenase activity (12.59 µg TPF/g/24 h), whereas the maximum fungal population (13.33 × 104 CFU/g soil) and acid phosphatase activity (14.45 µg pNP/g soil/h) were found in 75% RDF along with 10 t/ha PB and control treatment, respectively. This study concluded that application of invasive weed biochar along with inorganic fertilizers can benefit fodder yield and quality of oats by increasing plant height and number of tillers directly and by improving nutrient availability and water holding capacity (WHC) of soil indirectly, besides improving soil health. The findings from this study will provide a potential strategy for invasive weed management.

Systemic treatments in Parthenium dermatitis: A systematic review and meta-analysis.

Parthenium dermatitis is the commonest form of plant dermatitis in India, caused by the plant Parthenium hysterophorus. Systemic immunosuppressives are commonly employed in its treatment. However, there is a relative lack of comparative head-to-head trials. This study was done to assess the relative efficacy and safety of systemic treatments in Parthenium dermatitis. We systematically reviewed all the published studies investigating the safety and efficacy of systemic treatments for Parthenium dermatitis in the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, and clinical trial registries. Treatment benefit data were tabulated based on outcome measures of scoring systems. The quality of evidence for each outcome was assessed by Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria for meta-analysis. The pooled Standardized mean difference (SMD) for case series and comparative studies based on clinical severity score (CSS) for azathioprine was 4.007 (95% CI (Confidence interval): 3.141, 4.873) and 0.746 (95% CI: 0.139, 1.352), respectively. About 88.8% (95% CI: 76.8%, 100.8%, p = 0.076) of the patients had excellent or a good response to azathioprine. Our meta-analysis shows that azathioprine has the highest level of evidence in the treatment of Parthenium dermatitis.

A Study of the Chemical Composition, Acute and Subacute Toxicity of Bulgarian Tanacetum parthenium Essential Oil.

BACKGROUND: Tanacetum parthenium (L.) Sch.Bip. (T. parthenium) is an aromatic perennial plant belonging to the Asteraceae family, also known as feverfew. It is widely distributed in various regions of Europe and other parts of the world. The plant has a rich background in the traditional medicine of many nations and has been used as a remedy for fever, pain, inflammation, asthma, rheumatism, menstrual disorders, etc. Methods: GC-MS analysis was conducted to determine the chemical composition of the isolated essential oil (EO). Using the method proposed by Litchfield and Wilcoxon, the average lethal dose (LD50) of the EO on Wistar rats was determined for two routes of administration: oral (p.o.) and intraperitoneal (i.p.). The subacute toxicity of the EO was also tested by oral administration of a daily dose of 1.0 g/kg body weight (BW) for 28 days. The toxicity of the EO was evaluated by observing and evaluating changes in behavior, body weight, basic hematological and serum biochemical parameters, and histopathological changes of the internal organs. RESULTS: Thirty-seven volatile organic compounds representing 94.58% of the total oil composition were tentatively detected in the obtained T. parthenium EO. The dominant compounds were camphor (45.47%), trans-chrisantenyl acetate (21.65%), camphene (9.48%), and cis-isogeraniol (5.42%). The results showed that the EO was not toxic when administered in acute oral doses. The acute mean lethal dose for intraperitoneal administration was LD50 i.p. = 2.13 g/kg BW. In the subacute study involving administration of an oral dose of EO for 28 days, there were a number of changes in the hematological and serum biochemical parameters of the blood compared with the control group of animals. However, no symptoms of toxicity, changes in the body weight of the rats, death, or pathological changes in the histological indicators of the examined organs-brain, heart, stomach, liver, spleen and kidney-were found. Extrapolating the results obtained from the rat experiments, we can state that the EO is safe for use in doses below 1 g/kgBW for a period not exceeding one month.

Phytochemical Investigation, Antioxidant Properties and In Vivo Evaluation of the Toxic Effects of Parthenium hysterophorus.

Parthenium hysterophorus L. is a poisonous Asteraceae weed. The phytochemical profile, antioxidant activity, total phenolic contents (TPC), total flavonoid contents (TFC), and cytotoxicity of Parthenium hysterophorus L. flower extract were evaluated in this study, and the toxic effects were assessed in rabbits. The HPLC-DAD system was used for phytochemical analysis. The hemolytic and DPPH assays were performed. The effects of orally administering the flower crude extract to rabbits (n = 5) at four different doses (10, 20, 40, and 80 mg/kg) for ten days on hematological and biochemical parameters were investigated. The crude extract of the flower contained phenolic compounds such as Gallic acid, Chlorogenic acid, Ellagic acid, and P Coumaric acid, which were detected at different retention times, according to the HPLC results. With a sample peak of 4667.475 %, chlorogenic acid was abundant. At concentrations of 80 µg, the methanolic extract of flowers had total phenolic contents (89.364 ± 4.715 g GAE/g) and total flavonoid contents (65.022 ± 2.694 g QE/g). In the DPPH free radical scavenging assay, 80 µg of extract had the highest cell inhibition of 76.90% with an IC50 value of 54.278 µg/µL, while in the hemolytic assay 200 µg of extract had the highest cell inhibition of 76.90% with an IC50 > 500. The biochemical and hematological parameters were altered in the flower extract-fed groups as compared to the control (p < 0.05). The toxic effects on the blood, liver, and kidneys were confirmed. The findings also confirmed the presence of phenolic and flavonoid content in the flower extract, both of which contribute to the plant's antioxidant potential.

Essential Oils from Vietnamese Asteraceae for Environmentally Friendly Control of Aedes Mosquitoes.

Mosquitoes, in addition to being a biting nuisance, are vectors of several pathogenic viruses and parasites. As a continuation of our work identifying abundant and/or invasive plant species in Vietnam for use as ecologically friendly pesticidal agents, we obtained the essential oils of Blumea lacera, Blumea sinuata, Emilia sonchifolia, Parthenium hysterophorus, and Sphaeranthus africanus; analyzed the essential oils using gas chromatographic techniques; and screened the essential oils for mosquito larvicidal activity against Aedes aegypti and Aedes albopictus. The most active larvicidal essential oils were B. sinuata, which was rich in thymohydroquinone dimethyl ether (29.4%), (E)-ß-caryophyllene (19.7%), α-pinene (8.8%), germacrene D (7.8%), and α-humulene (4.3%), (24-h LC50 23.4 and 29.1 µg/mL) on Ae. aegypti and Ae. albopictus, respectively, and Emilia sonchifolia, dominated by 1-undecene (41.9%) and germacrene D (11.0%), (24-h LC50 30.1 and 29.6 µg/mL) on the two mosquito species. The essential oils of P. hysterophorus and S. africanus were also active against mosquito larvae. Notably, B. sinuata, P. hysterophorus, and S. africanus essential oils were not toxic to the non-target water bug, Diplonychus rusticus. However, E. sonchifolia essential oil showed insecticidal activity (24-h LC50 48.1 µg/mL) on D. rusticus. Based on these results, B. sinuata, P. hysterophorus, and S. africanus essential oils appear promising for further investigations.

Host plant-mediated effects of elevated CO2 and temperature on growth and developmental parameters of Zygogramma bicolorata (Coleoptera: Chrysomelidae).

Mexican beetle, Zygogramma bicolorata Pallister (Coleptera: Chrysomelidae) is a potential weed control biocontrol agent in Australia, India and other countries. Its grubs and adults feed on the leaves of parthenium weed, Parthenium hysterophorus and check the further growth of the plant. Experiments were conducted to understand host plant-mediated effects of elevated temperature and elevated CO2 on biocontrol agent Z. bicolorata. Food consumption, utilization, ecological efficiency and life-table parameters of Z. bicolorata were studied in grubs and adults stage up to diapause. Reduction of leaf nitrogen in parthenium weed foliage with a significant increase in carbon and C:N ratio was recorded at elevated CO2. Elevated CO2 and temperature had no effect on adult longevity before diapausing. Duration of egg's hatching, specific stages of grub and pupa of Z. bicolorata were significantly longer when beetles fed on leaves grown under elevated CO2 but these parameters decreased significantly on leaves grown under elevated temperature. Significantly high consumption rates with low growth and digestion conversions were observed under elevated CO2 and/or in coupled with elevated temperature. Elevated CO2 and temperature-grown parthenium weed foliage also had a significant effect on Z. bicolorata intrinsic rate of increase (R), finite rate of increase (λ), mean generation time (T), and gross reproductive rate. Changed quality of parthenium weed leaves in elevated CO2 and temperature levels resulted in the increase of consumption, slower food conversion rates, increase in developmental period with reduced reproduction efficiency of Z. bicolorata. Our results indicate that the reproduction efficiency of Z. bicolorata is likely to be reduced as the climate changes, despite increased feeding rates exhibited by grubs and adult beetles on parthenium weed foliage.

Parthenium hysterophorus: A tale of global invasion over two centuries, spread and prevention measures.

Ever since parthenium weed (Parthenium hysterophorus L.) first left its native range more than two centuries ago, this noxious herb has now invaded 46 countries and territories. The weed has expanded its range from a couple of islands in 18th Century through 11 minor and eight major introductions around the world. Segmented regression analyses confirmed introductions and revealed that the weed has spread fastest in developing countries, especially after the 1950s in Asia and Africa. A review of historical records, research papers and reports suggests that while border traffic (36%) and unchecked imports (seeds 16%, other commodities 17%) have resulted in the majority of international introductions, local spread has been achieved through multiple pathways, including roads and vehicles, by water and wind, through contaminated seed feed lots and floral bouquets. The high proportion of adjacent counties (51%) and oversea islands (5%) over the unknown origins (32%) or directly from the native range (12%) reveal a steady and predictable international spread pattern. Prevention of spread by management was first practised in Australia, then followed by other five countries. Containment barriers were set up, legislation on biosecurity imposed, and management plans based on early detection and eradication were executed; and these measures have been effective. Awareness within international research groups is raising, however, insufficient coordination between invaded countries has occurred to date, with policies yet to be formalised and executed to prevent the spread and impact of this weed.

Feasible or foolish: Attempting restoration of a Parthenium hysterophorus invaded savanna using perennial grass seed.

The annual herb Parthenium hysterophorus L. (Asteraceae), remains one of Southern Africa's most significant invasive weeds, commonly invading savannas, and their rangelands, causing severe losses to agriculture, livestock production and native biodiversity. Previous studies have suggested that perennial grasses may act as useful competitive species, capable of suppressing the growth and invasion of P. hysterophorus. To explore this, a total of 48 plots were established within an invaded savanna, using a randomised block design, and included treatments with and without the clearing of P. hysterophorus, as well as with and without the sowing of native perennial grass seed (Anthephora pubescens, Chloris gayana, Cynodon dactylon, Digitaria eriantha, Eragrostis curvula, Panicum maximum and Themeda triandra). Plots were assessed yearly in terms of P. hysterophorus density and growth as well as grass species composition, basal cover, and biomass over a three-year period. Clearing alone was found to exacerbate invasion, increasing P. hysterophorus density by 40%. Whereas the sowing of grass seed, in both the cleared and uncleared plots, increased the abundance of perennial grass species by 28%, subsequently reducing the size, reproductive output and density of P. hysterophorus over the three years. In addition, these sowing efforts contributed towards partial restoration of the plots, enhancing grass basal cover by ~15% and biomass production by 17%. Overall, this research suggests that sowing of native grass species, with or without clearing, may be a useful supplementary control or restoration tool towards the long-term management of P. hysterophorus invasions in managed savannas and rangelands in Southern Africa.

Impact of Parthenium hysterophorus L. invasion on soil nitrogen dynamics of grassland vegetation of Indo-Gangetic plains, India.

The noxious plant species Parthenium hysterophorus L. has become a major concern for the conservation of many natural and managed areas. The species is known for its various adverse effects on the invaded ecosystems, particularly in terms of biodiversity loss. Currently, P. hysterophorus is a leading invasive species widespread in the grasslands of productive and diversity rich Indo-Gangetic plains of India and is responsible for various changes in the ecosystem. The present study addresses the changes that P. hysterophorus can bring in the vegetation structure (species richness, species evenness, and species composition) of the grasslands of Indo-Gangetic plain. To broaden our understanding of the invasion success and facilitated expansion, we also focus on the variability of soil nitrogen pool and processes as a consequence of invasion. We report that in the presence of P. hysterophorus, the species diversity, evenness, composition and richness were altered, affecting many native and non-native flora of the ecosystem. The effect was more prominent during the second and third year of the study with more increase in the invasion outcomes. Significant changes in soil nitrogen (N) dynamics, particularly, increased available (N), N-mineralization and microbial biomass N have been found in the invaded plots along with changes in vegetation of the grassland community. Overall, the result suggested that the invasive species, P. hysterophorus, modifies the soil and this modification is correlated with changes in vegetation structure and this situation is likely to further facilitate severe alterations in the ecosystem and could favor encroachment of other non-native species in the area.

Assessment of Lead and Cadmium Pollution in Soil and Wild Plants at Different Functional Areas of Sialkot.

Heavy metal pollution is a great hazard to the environment that enters the ecosystem through different natural and anthropogenic sources. A study was performed to evaluate concentrations of Cd and Pb in selected plants, Ricinus communis and Parthenium hysterophorus, and soils from different functional sites in Sialkot. Maximum fresh and dry weights of R. communis were recorded from control and field sites. Highest concentrations of Cd in P. hysterophorus (33.5 mg kg-1) and R. communis (24.36 ± 2.83 mg kg-1) were recorded at residential and industrial sites, respectively. However, road site samples showed maximum concentrations of Pb both in R. communis (9.06 ± 0.35 mg kg-1) and P. hysterophorus (7.90 ± 0.36 mg kg-1). Soil from the road site were found to be highly acidic (pH 4.75 ± 0.04), while the field site showed highest EC (494 ± 3.60) and TDS (509 ± 3.00) values. Generally, there were reductions in chlorophyll a and carotenoids, but an increase in chlorophyll b was observed in both plants at all sites compared to the control.

Increase in concentration of patch test allergen reduces patch test occlusion time to 12 hours without affecting patch test reactivity in patients with parthenium dermatitis.

BACKGROUND: Patch testing is the standard method to diagnose contact allergy. Patches are applied for 48 hours, which is inconvenient to patients in tropical weather. Therefore, we evaluated different patch test occlusion times with increased concentrations of an allergen to determine if occlusion time can be reduced without compromising patch test reactivity. METHODS: Patch test positive patients with parthenium dermatitis were enrolled and patch tested using five different concentrations (10%, 4%, 2%, 1%, and 0.5%) of parthenium extract. The patches were applied in triplicate. The first set was removed after 12 hours, whereas the second and third sets were removed after 24 and 48 hours, respectively. Readings were performed at 24, 48, and 96 hours. RESULTS: Fifty patients with parthenium dermatitis were included. The positive patch test reaction rates were comparable in all three sets at 24- and 48-hour readings irrespective of the occlusion time. All were positive, with 10%, 4%, and 2% concentrations at 96-hour reading with an occlusion time of 12 hours. CONCLUSION: An occlusion time of 12 hours seems adequate to elicit positive patch test reaction at a 96-hour reading if the concentration of patch test allergen can be increased, that is, from 1% to 2% in these patients.

Cytokine storm in COVID-19 and parthenolide: Preclinical evidence.

A group of patients with pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were reported from China in December 2019. Although several antiviral drugs are widely tested, none of them has been approved as specific antiviral therapy for coronavirus disease 2019 (COVID-19). Accumulating evidence established a hyperinflammatory states or cytokine storm in COVID-19. Among these cytokines, IL-6 plays a key role in cytokine storm and can predict the adverse clinical outcomes and fatality in these patients. Based on the evidence of the significant role of IL-6 in cytokine storm, diabetes mellitus, and cardiovascular diseases as principal comorbidities, it seems that anti-cytokine therapy may be useful in patients with severe COVID-19 to reduce mortality. Recent studies demonstrated that herbal-derived natural products had immunosuppressive and anti-inflammatory properties and exhibited exceptional act on mediators of inflammation. Parthenolide is the principal sesquiterpene lactones and the main biologically active constituent Tanacetum parthenium (commonly known as feverfew) which has could significantly reduce IL-1, IL-2, IL-6, IL-8, and TNF-α production pathways established in several human cell line models in vitro and in vivo studies. Therefore, parthenolide may be one of the herbal candidates for clinical evaluation.

Parthenium hysterophorus mediated inflammation and hyper-responsiveness via NF-κB pathway in human A549 lung cancer cell line.

Being one of the notorious weed P. hysterophorus has invaded almost every part India and is the lead cause of skin allergies and severe dermatitis among farmers and rural population. It is an invasive obnoxious weed capable of surviving extreme environmental conditions and various parts of this plant are reported to cause severe contact allergies in humans due to the presence of high concentrations of toxic sesquiterpene lactones viz. parthenin. It can stimulate numerous cellular and immune responses that may translate into Oxidative stress, allergies, and inflammation. The effect of P. hysterophorus flower extract was evaluated on cell viability, oxidative stress and inflammation in A549 lung cancer cell line by spectrophotometric and reverse transcriptase-polymerase chain reaction methods. Schrodinger software based docking was performed for possible interactions studies. The A549 cells treated with P. hysterophorus flower extract favors increase in cell viability, reactive oxygen species generation. The mRNA expression of proinflammatory cytokines such as IFN-γ, TNF-α, and IL-1ß was significantly increased whereas no change in IL-18 expression was observed. Significant increase in protein expression of NF-κB was observed, suggesting the role of NF-κB signalling in allergic responses. The docking studies demonstrated the potential interaction between Parthenin and NF-κB/IL-1ß/IL-18 suggesting their activation leading to inflammation. The current study emphasize that P. hysterophorus mediates oxidative stress, and inflammatory process via alterations in expression of proinflammatory cytokines such as IL-1ß, IFN-γ through NF-κB activation which was also confirmed in docking studies. Cellular and molecular mechanisms involved in pathogenesis of allergic/chronic inflammation and severe dermatitis need to be further investigated to identify specific binding partners responsible for severe inflammation which can provide some leads in developing effective targets against severe dermatitis and skin allergies.

Reducing the fitness of an invasive weed, Parthenium hysterophorus: Complementing biological control with plant competition.

We studied the effects of a biological control agent, Epiblema strenuana Walker (Lepidoptera: Tortricidae) alone and together with a sown native grass, Astrebla squarrosa C.E. Hubb. and an introduced pasture plant, Clitoria ternatea L. on growth and seed production of Parthenium hysterophorus L. Astrebla squarrosa and C. ternatea individually reduced shoot dry biomass of P. hysterophorus by 30 and 42%, respectively; and by 48 and 70%, respectively in the presence of biological control agent, E. strenuana. Similarly, A. squarrosa and C. ternatea individually reduced weed seed production up to 48 and 64%, respectively; and by 73 and 81%, respectively in the presence of E. strenuana. In the presence of E. strenuana, the biomass of A. squarrosa and C. ternatea was increased by 13 and 10%, respectively. The biological control agent induced more galls per P. hysterophorus plant when either of the competing plants were present than when grown alone. The abundance of galls increased with pasture competition, but only for C. ternatea, and not for A. squarrosa. The biological control agent worked synergistically with the two competitive plants to reduce the growth and production of viable seed, which should lead to a decrease in the P. hysterophorus soil seed banks in the field, and eventually seedling recruitment in future generations of P. hysterophorus.

Green Synthesis of Silver Nanoparticles Using Parthenium Hysterophorus: Optimization, Characterization and In Vitro Therapeutic Evaluation.

Traditional synthetic techniques for silver nanoparticles synthesis involve toxic chemicals that are harmful to humans as well as the environment. The green chemistry method for nanoparticle synthesis is rapid, eco-friendly, and less toxic as compared to the traditional methods. In the present research, we synthesized silver nanoparticles employing a green chemistry approach from Parthenium hysterophorus leaf extract. The optimized parthenium silver nanoparticles (PrSNPs) had a mean particle size of 187.87 ± 4.89 nm with a narrow size distribution of 0.226 ± 0.009 and surface charge -34 ± 3.12 mV, respectively. The physicochemical characterization of optimized SNPs was done by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Moreover, the transmission electron microscopy (TEM) analysis indicates the spherical shape of NPs with an average diameter of 20-25 nm. PrSNPs were investigated for in vitro antibacterial, antifungal, anti-inflammatory, and antioxidant properties, and showed excellent profiles. The cytotoxic activity was analyzed against two cancer cell lines, i.e., B16F10 and HepG2 for 24 h and 48 h. PrSNPs proved to be an excellent anticancer agent. These PrSNPs were also employed for the treatment of wastewater by monitoring the E. coli count, and it turned out to be reduced by 58%; hence these NPs could be used for disinfecting water. Hence, we can propose that PrSNPs could be a suitable candidate as an antimicrobial, antioxidant, anti-inflammatory, and antitumor agent for the treatment of several ailments.