Biodecolorization of Reactive Black 5 by laccasemediator system

Reactive azo dyes are widely used as textile colorants, typically for cotton dyeing, due to their variety of color shades, and minimal energy consumption. In the present study, commercial laccase from Trametes versicolor was used for the biodecolorization of Reactive Black 5 (RB-5) dye using different redox mediators viz, N-hydroxybenzotriazole (HBT), 2,2′-azino-bis-(3-ethylbenzthiazoline- 6-sulfonic acid (ABTS), 2,6-dimethoxy phenol (DMP), syringaldehyde, vanillin, aceto-vanillone, p-coumaric acid and catechol. Commercial laccase alone did not show any considerable decolorization of RB-5. However, the laccase in the presence of syringaldehyde showed the strongest decolorization rate (98%), followed by vanillin (55.21%), aceto-vanillone (53.25%), ABTS (42.78%), p-coumaric acid (41.9%), DMP (39%), and catechol (36.33%); while least decolorization was observed with HBT at dye/mediator ratio of only 1:5 after 30 min. Therefore, syringaldehyde performance was evaluated at different mediator/dye ratios (1:1, 1:5 and 1:10) using commercial laccase and it was compared with that of synthetic mediator like HBT. It was found that the presence of syringaldehyde was essential for biodecolorization of RB-5. Moreover, it was observed that syringaldehyde was an effective natural redox mediator as compared to synthetic HBT. Enhanced decolorization (98%) of RB-5 by laccase was observed with 1:5 syringaldehyde and dye ratio for 30 min but maximum removal (22%) of RB-5 was recorded with HBT at 1:1 after 40 min. Thus, the study reveals that the phenolic compounds could be used as potential redox mediators for enhanced laccase-mediated decolorization of azo dyes.Keywords: Reactive Black 5 (RB-5), redox mediators, laccase, biodegradation, azo dyesAfrican Journal of Biotechnology Vol. 11(29), pp. 7464-7471, 10 April, 201

Molecular Mechanisms and Strategies Contributing toward Abiotic Stress Tolerance in Plants

Plants respond to climate change via sensing the extreme environmental conditions at cell level, which initiated significant changes in their physiology, metabolism, and gene expression. At the cell membrane, plants activate certain genes (like GRP, PRP, AGP) to provide strengthening to cell wall. Drought and salinity stress tolerance attained by osmotic adjustments, activation of transcriptional factors (like AREB, ABF, DREB2), and regulation of Na+ homeostasis via transporters (like NSCC, NHX1, SOS1, HKT1, LTC1). For adaptations to chilling and frost stress, plants use hydrophobic barriers (waxes/cuticles), antinucleator (cryoprotective glycoprotein), and antifreeze proteins. Higher expression of HSPs (heatshock proteins such as HSP70, HSP100, HSP90, HSP60) is important for thermal tolerance. Tolerance to heavy metal (HM) stress can be achieved via vacuolar sequestration and production of phytochelatin, organic acids and metallothionein. ROS generated due to abiotic stresses can be alleviated through enzymatic (APX, CAT, POD, SOD, GR, GST) and nonenzymatic (ascorbate, glutathione, carotenoids, flavonoids) antioxidants. Genetic manipulation of these genes in transgenic plants resulted in better tolerance to various abiotic stresses. Genetic engineering of plants through various genome editing tools, such as CRISPR/Cas9, improve the abiotic stress tolerance as well as enhance the crops’ quality, texture, and shelf life

Uloga prijeoperacijskog karcinoembrijskog antigena u recidiviranju resektabilnog kolorektalnog karcinoma

In colorectal carcinoma, carcinoembryonic antigen (CEA) is a recommended marker for surveillance after curative resection. The aim of the present study was to determine the association of preoperative CEA with recurrence of colorectal carcinoma in our population. The study included 55 patients with all operable stages of colorectal adenocarcinoma treated during the 2012-2014 period, evaluated retrospectively and followed-up for recurrence for 2 years. Data on the baseline (preoperative) CEA levels were retrieved from patient files. On data analysis, SPSS 16.0 was used. In patients with normal preoperative CEA, the rate of recurrence was significantly low (p=0.008) and the likelihood of no recurrence 1.55-fold greater as compared to patients with raised initial CEA levels (p=0.028). In patients with raised preoperative CEA, the risk of recurrence was 5.26-fold greater as compared to those with normal CEA levels (p=0.028). A significant weak positive correlation (rs=0.297) was found between raised CEA and recurrence. A highly significant (p=0.002) moderate positive correlation was recorded in patients aged <50 and moderate positive correlation of borderline significance in males (rs=0.324, p=0.058). Sensitivity was 94.4% and specificity 32.4% in predicting recurrence. Accordingly, preoperative elevated CEA showed a significant weak positive correlation with recurrence while normal preoperative CEA moderately decreased the likelihood of recurrence.U kolorektalnom karcinomu preporuča se karcinoembrijski antigen (CEA) kao biljeg u praćenju bolesnika nakon resekcije karcinoma. Cilj ovoga istraživanja bio je utvrditi udruženost prijeoperacijske razine CEA s recidiviranjem kolorektalnog karcinoma u našoj populaciji. U istraživanje je bilo uključeno 55 bolesnika sa svim operabilnim stadijima kolorektalnog adenokarcinoma liječenih u razdoblju od 2012. do 2014. godine. Bolesnici su retrospektivno procijenjeni i praćeni zbog recidiva tijekom dvije godine. Podaci o bazalnim (prijeoperacijskim) razinama CEA preuzeti su iz medicinske dokumentacije bolesnika. Analiza podataka provedena je pomoću SPSS 16.0. Kod bolesnika s normalnom prijeoperacijskom razinom CEA stopa recidiva bila je značajno niža (p=0,008), a vjerojatnost izostanka recidiva 1,55 puta veća u usporedbi s bolesnicima s povišenim početnim razinama CEA (p=0,028). Kod bolesnika s povišenim prijeoperacijskim razinama CEA rizik od recidiva bio je 5,26 puta veći u usporedbi s onim u bolesnika s normalnim razinama CEA (p=0,028). Značajna slabo pozitivna korelacija (rs=0,297) utvrđena je između povišene razine CEA i recidiva. Visoko značajna (p=0,002) umjereno pozitivna korelacija zabilježena je u bolesnika mlađih od 50 godina te umjereno pozitivna korelacija granične značajnosti kod muškaraca (rs=0,324, p=0,058). Utvrđena je osjetljivost od 94,4% i specifičnost od 32,4% u predviđanju recidiva. Dakle, povišena prijeopearcijska razina CEA pokazala je značajnu slabo pozitivnu korelaciju s recidivima, dok je normalna prijeoperacijska razina CEA umjereno snizila vjerojatnost recidiva

The Impact of Investment, Economic Growth, Renewable Energy, Urbanisation, and Tourism on Carbon Emissions: Global Evidence

Examining urbanisation and tourism from the perspective of global Sustainable Development Goals is essential for achievinga balance between environmental protection and economic growth in the world's most polluted nations. Moreover, most polluted countries pay more attention to the nature of foreign direct investment (FDI) inflows to achieve a sustainableenvironment. This study intends to explore the impacts of FDI, tourism, urbanization, and economic growth on carbon dioxide emissions using panel data for the top ten most polluted nations for the period from 2000 to 2019. To guide empirical testing,the panel unit root tests LLC and IPS are used. The outcomes of LLC and IPS advise FM-OLS application on how to accomplish the goals. The findings provide proof of how FDI and other factors affect carbon emissions (CE). Particularly, renewable energy consumption (REC) has a detrimental but minor effect on CE. For the panel of developing nations, FDI had a favourable and significant effect on CE along with economic growth, tourism, and urbanization. The expansion of cities isalso harming nature and ecological footprints. These findings are alarming as all factors cause CE under consideration thatleads to the deterioration of the environment. Therefore, more environmental rules should be put into place to reduce CE, draw in clean FDI, and encourage quality-oriented investment in selected nations. Second, it is important to ensure the deployment of green technology and the upgrading of urbanized structures. The government can take several actions against the use of polluting goods and vehicles in urban areas, and any polluting industries should also be outlawed in such residential areas

Comparative arsenic tolerance and accumulation potential between wild Tagetes patula and Tagetes minuta

Arsenic (As) is a bioactive metalloid that is highly toxic to humans, animals, and plants. Environmental contamination of As especially in groundwater increases due to natural and anthropogenic activities. The present study was performed to evaluate the potential of wild Tagetes species for the phytoremediation of As contaminated soil/water. This comparative research aims to analyze As accumulation and tolerance in two wild species of Tagetes, T. minuta and T. patula. The 20 days old seedlings were grown hydroponically and exposed to the different concentrations of As, 0, 50, 150, and 300 µM As2 O3 for 1-, 4- and 7- days intervals.Effect of As stress was measured on the rate of seed germination, growth parameters like fresh and dry biomass weight, root/shoot length, chlorophyll contents and As contents in root and shoot in both Tagetes species. Increasing concentration of As restricts the growth activity of T. minuta with toxicity symptoms on leaves such as chlorosis. Accumulation of As in the shoot was significantly (p ≤ 0.01) high (634 µg g-1 DW) in T. patula as compared to T. minuta (397 µg g-1 DW) at 300 µM As2 O3 . Both Tagetes species exhibited high variation for As tolerance parameters as well as for As accumulation patterns. Comparatively good tolerance and accumulation of As in T. patula suggests that this species could be used in phytoextraction and re-vegetation in As contaminated sites

Salt and heavy metal tolerance and expression levels of candidate tolerance genes among four extremophile Cochlearia species with contrasting habitat preferences

To test the concept of a general “mineral stress tolerance”, we compared four extremophile Cochlearia species for salt (NaCl), zinc (Zn) and cadmium (Cd) tolerance and accumulation, and for expression of candidate tolerance genes for salt and Zn tolerance. Salt tolerance decreased in the order C. anglica > C. x hollandica > C. danica > C. pyrenaica, corresponding with the average salinity levels in the species' natural environments. The glycophytic metallophyte, C. pyrenaica, showed a relatively high level of salt tolerance, compared to other glycophytic Brassicaceae. Salt tolerance was positively correlated with HKT1 expression and the K+ concentration in roots under salt exposure, but uncorrelated with the Na+ concentrations in roots and shoots. All the species accumulated Na+ primarily in their leaves, and exhibited a high NHX1 expression in leaves, in comparison with other glycophytic Brassicaceae, suggesting that salt tolerance in Cochlearia is based on an efficient vacuolar sequestration of Na+ in leaves. The metallicolous C. pyrenaica population was hypertolerant to Zn, but not to Cd, in comparison with the other Cochlearia species. All the Cochlearia species accumulated Zn and Cd primarily in roots, and showed high levels of Cd and Zn tolerance, with unusually low rates of metal accumulation, in comparison with non-metallophytes, or non-metallicolous metallophyte populations, of species belonging to other genera or families. Although Cochlearia, as a genus, shows relatively high levels of tolerance to both salt and heavy metals, this is most probably not due to a common ‘mineral stress tolerance’ mechanism

Analyzing the Impact of Governance, Environment and Trade on Inward FDI: A Case of Cambodia, Thailand and Vietnam from ASEAN

The purpose of the study is to analyze the empirical link between governance, environmental quality, and trade as it relates to foreign direct investment in Cambodia, Thailand, and Vietnam for the period ranging from 1996 to 2022. Mixed order of integration (0 and 1) was discovered after applying four panel unit tests (IPS-W stat, ADF- Fisher, PP-Fisher, and LLC t). The Kao Residual Co-integration test was carried out to determine whether there was co-integration among the variables of the study. The results of the test demonstrated that some variables are, in fact, co-integrated during the investigation. The findings of unit root tests reveal the use of Panel ARDL, and the results demonstrate that governance has a positive overall effect on FDI. This is because tightening the control of corruption, improving regulatory quality, and strengthening the rule of law are all contributing to an increase in FDI in Cambodia, Thailand, and Vietnam. The study concluded that there is a link between a negative opinion of the efficacy of the government and foreign direct investment; however, this association did not reach the level of statistical significance required to be considered significant. To encourage FDI, trade also provides access to natural resources as the free flow of raw materials and intermediate goods is being supported by the initiatives connected to the promotion of FDI, which is made possible through trade

Salt and heavy metal tolerance and expression levels of candidate tolerance genes among four extremophile Cochlearia species with contrasting habitat preferences

To test the concept of a general “mineral stress tolerance”, we compared four extremophile Cochlearia species for salt (NaCl), zinc (Zn) and cadmium (Cd) tolerance and accumulation, and for expression of candidate tolerance genes for salt and Zn tolerance. Salt tolerance decreased in the order C. anglica > C. x hollandica > C. danica > C. pyrenaica, corresponding with the average salinity levels in the species' natural environments. The glycophytic metallophyte, C. pyrenaica, showed a relatively high level of salt tolerance, compared to other glycophytic Brassicaceae. Salt tolerance was positively correlated with HKT1 expression and the K+ concentration in roots under salt exposure, but uncorrelated with the Na+ concentrations in roots and shoots. All the species accumulated Na+ primarily in their leaves, and exhibited a high NHX1 expression in leaves, in comparison with other glycophytic Brassicaceae, suggesting that salt tolerance in Cochlearia is based on an efficient vacuolar sequestration of Na+ in leaves. The metallicolous C. pyrenaica population was hypertolerant to Zn, but not to Cd, in comparison with the other Cochlearia species. All the Cochlearia species accumulated Zn and Cd primarily in roots, and showed high levels of Cd and Zn tolerance, with unusually low rates of metal accumulation, in comparison with non-metallophytes, or non-metallicolous metallophyte populations, of species belonging to other genera or families. Although Cochlearia, as a genus, shows relatively high levels of tolerance to both salt and heavy metals, this is most probably not due to a common ‘mineral stress tolerance’ mechanism