Efficient performance of InP and InP/ZnS quantum dots for photocatalytic degradation of toxic aquatic pollutants.

In recent years, the growing concern over the presence of toxic aquatic pollutants has prompted intensive research into effective and environmentally friendly remediation methods. Photocatalysis using semiconductor quantum dots (QDs) has developed as a promising technology for pollutant degradation. Among various QD materials, indium phosphide (InP) and its hybrid with zinc sulfide (ZnS) have gained considerable attention due to their unique optical and photocatalytic properties. Herein, InP and InP/ZnS QDs were employed for the removal of dyes (crystal violet, and congo red), polyaromatic hydrocarbons (pyrene, naphthalene, and phenanthrene), and pesticides (deltamethrin) in the presence of visible light. The degradation efficiencies of crystal violet (CV) and congo red (CR) were 74.54% and 88.12% with InP, and 84.53% and 91.78% with InP/ZnS, respectively, within 50 min of reaction. The InP/ZnS showed efficient performance for the removal of polyaromatic hydrocarbons (PAHs). For example, the removal percentage for naphthalene, phenanthrene, and pyrene was 99.8%, 99.6%, and 88.97% after the photocatalytic reaction. However, the removal percentage of InP/ZnS for pesticide deltamethrin was 90.2% after 90 min light irradiation. Additionally, advanced characterization techniques including UV-visible spectrophotometer (UV-Vis), photoluminescence (PL), X-ray diffractometer (XRD), energy-dispersive spectrometer (EDS) elemental mapping, transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) were used to analyze the crystal structure, morphology, and purity of the fabricated materials in detail. The particle size results obtained from TEM are in the range of 2.28-4.60 nm. Both materials (InP and InP/ZnS) exhibited a spherical morphology, displaying distinct lattice fringes. XRD results of InP depicted lattice planes (111), (220), and (311) in good agreement with cubic geometry. Furthermore, the addition of dopants was discovered to enhance the thermal stability of the fabricated material. In addition, QDs exhibited efficacy in the breakdown of PAHs. The analysis of their fragmentation suggests that the primary mechanism for PAHs degradation is the phthalic acid pathway.

Nickel uptake in leafy greens from contaminated soil: an investigation into phytoavailability and health risk assessment using in vitro digestion model.

Nickel (Ni) is a toxic metal that not only pollutes the environment but also causes harmful impacts on plant growth and human health. Therefore, it is crucial to assess the relationship between the phytoavailability of Ni in soil and its accumulation in edible and non-edible parts of vegetables. A pot experiment was conducted to investigate Ni uptake in three different leafy vegetables, spinach (Spinacia oleracea L.), lettuce (Lactuca sativa L.), and fenugreek (Trigonella foenum-graecum L.), grown in soil artificially contaminated with Ni at three different treatment levels (100 mg kg-1, 200 mg kg-1, and 300 mg kg-1). The potential dietary toxicity of these vegetables in humans was examined by using an in vitro digestion model. The lowest and highest chlorophyll contents were detected in lettuce at 300 mg kg-1 of Ni concentration and in control plants of spinach. Their values were 34.16 ± 3.01 (SPAD unit) and 53 ± 3.7673 (SPAD unit), respectively. Among the three vegetables, lettuce and spinach at 300 mg kg-1 exhibited the highest accumulation of Ni, with 43 mg kg-1 in edible parts and 182 mg kg-1 in non-edible parts. Furthermore, health risk index (HRI) values were found to be > 1 for lettuce and fenugreek at Ni concentrations of 200 and 300 mg kg-1 for both children and adults. The average bioaccessibility of Ni in lettuce, fenugreek, and spinach during the gastrointestinal phase was 32-23%, 24-10%, and 45-37%, respectively, at a Ni concentration of 300 mg kg-1. All three vegetables grown on Ni-contaminated soil may potentially contribute to food chain toxicity. The HRI values being > 1 suggest that these vegetables are unsafe for consumption. Monitoring of Ni concentration in leafy vegetables is essential to minimize human health risks associated with food chain contamination.

Effectiveness of lower limb rehabilitation protocol using mobile health on quality of life, functional strength, and functional capacity among knee osteoarthritis patients who are overweight and obese: A randomized-controlled trial.

Objectives: This study aims to investigate the effectiveness of the lower limb rehabilitation protocol (LLRP) using mobile health (mHealth) on quality of life (QoL), functional strength, and functional capacity among knee OA patients who were overweight and obese. Patients and methods: Between August 2019 and November 2020, a total of 96 patients (42 males, 54 females; mean age; 52.9±4.8 years; range, 40 to 60 years) were randomized into either the rehabilitation group with mobile health (RGw-mHealth) receiving reminders by using mHealth to carry on the strengthening exercises of LLRP and instructions of daily care (IDC), the rehabilitation group without mobile health (RGwo-mHealth) following the strengthening exercises of LLRP and instructions of daily care (IDC) and control group (CG) only following the IDC for duration of 12 weeks. The reminders for using mHealth were provided two times a day for three days a week. Primary outcome measures were QoL assessed by the Western Ontario and McMaster Universities Osteoarthritis Index summary score, and functional strength by five-repetition sit-to-stand test. Secondary outcome measure was functional capacity assessed by the Gait Speed Test. The assessments of QoL, functional strength, and functional capacity were taken at baseline and post-test after 12 weeks of intervention. Results: After 12 weeks of intervention, the patients in all three groups had a statistically significant improvement in QoL within groups (p<0.05). Patients in the RGw-mHealth and RGwo-mHealth had a statistically significant improvement in functional strength and walking gait speed within groups (p<0.05). The pairwise between-group comparisons (Bonferroni post-hoc test) of the mean changes in QoL, functional strength, and functional capacity at post-test assessments revealed that patients in the RGw-mHealth had a statistically significant greater mean change in QoL, functional strength and functional capacity relative to both the RGwo-mHealth and CG (p<0.001). Conclusion: The improvement in QoL, functional strength, and functional capacity was greater among patients in the RGw-mHealth compared to the RGwo-mHealth or CG.

Occurrence, source identification and ecological risk assessment of heavy metals in water and sediments of Uchalli lake - Ramsar site, Pakistan.

Uchalli Lake is an internationally significant Ramsar site that needs protection for supporting migratory birds. The current study aimed to assess wetland health by examining water and sediments utilizing total and labile heavy metals concentration, pollution indices, ecological risk assessment, water recharge and pollution induction sources through isotope tracer techniques. Al concentration in water was of serious concern as it was 440 times higher than the maximum acceptable concentration of Environmental Quality Standard of the UK for aquatic life in saline waters. Labile concentration predicted very severe enrichment of Cd, Pb, and moderate enrichment of Cu. Modified ecological risk index predicted very high ecological risk in sediments. The δ 18O, δ2H and D-excess values indicate that the lake was mainly recharged by local meteoric water. Enriched values of δ 18O and δ2H suggest a high evaporation of lake water, making lake sediments more enriched with metals. Isotopic and D-excess values of groundwater suggest a quick rainwater recharge to groundwater around the Uchalli Lake. Nitrates isotopes indicate that the rainwater runoff is main source of induction of fertilizers, pesticides and soil bonded metals in the lake system. The lake is recharged by rainwater runoff, from catchment areas, that erode the soil particles and agricultural residual waste dumped in the lake.

Assessment of heavy metals and associated oxidative stress in occupationally exposed workers from Bannu and Karak Districts in Pakistan.

Heavy metals (HMs) are extensively found in occupationally exposed miners and industrial workers, which may cause serious health-related problems to the large workforce. In order to evaluate the impact of these toxic pollutants, we have investigated the effect of cadmium (Cd), chromium (Cr), copper (Cu), and lead (Pb) concentration on exposed workers of mining, and woolen textile mill and compared the findings with unexposed individuals. From each category like exposed workers (mining, and woolen mill textile site) and unexposed individuals, 50 blood samples were taken. The occurrence of HMs in a sample was investigated through atomic absorption spectrometry while the oxidative stress marker malondialdehyde (MDA) and antioxidant enzyme statuses such as superoxide dismutase (SOD) and catalase (CAT) were analyzed in exposed and control samples. The results showed significant (p < 0.05) variation in Cd, Cr, Cu, and Pb levels in exposed and control samples. The concentration of Cd in the blood of WMWs, KMWs, and control group was 5.75, 3.89, and 0.42 µg/dL, respectively. On the other hand, the concentration of Pb in the blood of WMWs, MWs, and control was 32.34, 24.39, and 0.39 µg/dL while the concentrations of Cr and Cu in the blood of WMWs, MWs, and control group were 11.61 and 104.14 µg/dL, 4.21 and 113.21 µg/dL, 0.32 and 65.53 µg/dL, respectively. An increase in MDA was recorded in the exposed workers' group as compared to control subjects, whereas SOD and CAT activities decreased. Meanwhile, MDA was significantly and positively (p < 0.01) correlated with HMs, while negative significant correlations were found among HMs with SOD and CAT.

Microplastic pollution in the surface water and sediments from Kallar Kahar wetland, Pakistan: occurrence, distribution, and characterization by ATR-FTIR.

This study reports the distribution of microplastics in surface water and sediments collected from Kallar Kahar wetland, Punjab, Pakistan, which is a game reserve and hosts migratory birds during winter season. Microplastics were extracted using density separation and wet oxidation method. The microplastics identification was done under a stereo-microscope, and their polymer compositions were characterized using an attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The average abundance of microplastics in water and sediment samples was 88 ± 14.5 items/L and 5720 ± 2580 items/kg, respectively. The dominant shape groups of microplastics in water were fiber (58.7%), irregular fragments (32.4%), and beads (8.7%) with dominant colors as transparent > black > yellow ≈ white > red > green > pink > blue. Similar distribution in sediments was found, i.e., fiber (61.2%), irregular fragments (28.4%), and beads (10.3%) with dominant colors as transparent > pink > white > red ≈ black > blue > brown > green ≈ yellow. The ATR-FTIR spectra of visible microplastics were identified to be polypropylene (PP), high density polyethylene (HDPE), ethylene vinyl acetate (EVA), low density polyethylene (LDPE), nitrile, polymethyl methacrylate (PMMA), latex, and polyethylene terephthalate (PETE). In the study area, recreational activities, improper waste disposal, and runoff from catchment areas are the main reasons for the contamination of microplastics in the Lake. The pollution load can be minimized by taking measures such as creating awareness, promotion of ecotourism, and reducing plastic use.

Development of Cerium Oxide/Corncob Nanocomposite: A Cost-Effective and Eco-Friendly Adsorbent for the Removal of Heavy Metals.

This research aims to assess the efficiency of the synthesized corncob as a cost-effective and eco-friendly adsorbent for the removal of heavy metals. Therefore, to carry out the intended research project, initially, the corncob was doped with nanoparticles to increase its efficiency or adsorption capacity. The prepared adsorbent was evaluated for the adsorption of cadmium (Cd) and chromium (Cr) from aqueous media with the batch experiment method. Factors that affect the adsorption process are pH, initial concentration, contact time and adsorbent dose. The analysis of Cd and Cr was performed by using atomic absorption spectrometry (AAS), while the characterization of the adsorbent was performed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results showed that there is a significant difference before and after corncob activation and doping with CeO2 nanoparticles. The maximum removal for both Cd and Cr was at a basic pH with a contact time of 60 min at 120 rpm, which is 95% for Cd and 88% for Cr, respectively. To analyze the experimental data, a pseudo-first-order kinetic model, pseudo-second-order kinetic model, and intra-particle diffusion model were used. The kinetic adsorption studies confirmed that the experimental data were best fitted with the pseudo-second-order kinetic model (R2 = 0.989) and intra-particle diffusion model (R2 = 0.979). This work demonstrates that the cerium oxide/corncob nanocomposite is an inexpensive and environmentally friendly adsorbent for the removal of Cd and Cr from wastewater.

The Role of Rehabilitation Exercises on Weight, Functional Strength, and Exercise Adherence in Knee Osteoarthritis Patients.

INTRODUCTION: Knee osteoarthritis (OA) is a weight-bearing joint disease and is more common in overweight and obese persons. The objective of this study was to determine the role of rehabilitation exercises (REs) of lower limbs on weight, functional strength, and exercise adherence in overweight and obese knee OA patients. MATERIALS AND METHODS: The patients were recruited from the urban community of Lahore, Pakistan. The patients were divided into the rehabilitation group (RG) and control group (CG). The patients in the RG performed the REs of lower limbs and followed the instructions of daily care (IDC), while the patients in the CG only followed the IDC for a 12 weeks period. Outcome measures were assessed at pre-test before grouping and post-test after 12-weeks of interventions. The measures included: weight, functional strength, and exercise adherence. The Paired Samples t-test (for normally distributed data) and the Wilcoxon Signed Ranked Test (for data that was not normally distributed) were used to analyze the differences within groups from pre to post-test measurements. The variance 2 × 2 factors and the Mann Whitney U-test were used to analyze the difference in weight and functional strength between the groups. RESULTS: The patients in the RG reported a statistically significant weight reduction (p < 0.001) and improvement in the functional strength (p < 0.001) within a group. Similarly, the patients in the CG also reported a significant improvement in the scores of functional strength (p = 0.004) within a group. The improvement in the scores of functional strength was higher in the patients of RG than the CG (p < 0.001). Similarly, the patients in the RG reported a statistically significant reduction in weight than the CG (p < 0.001). CONCLUSION: The REs could improve weight, functional strength and exercise adherence.

The effect of rehabilitation protocol using mobile health in overweight and obese patients with knee osteoarthritis: a clinical trial.

OBJECTIVE: The objective of this randomized controlled trial (RCT) was to investigate the effectiveness of the lower limb rehabilitation protocol (LLRP) combined with mobile health (mHealth) applications on knee pain, mobility, functional activity and activities of daily living (ADL) among knee osteoarthritis (OA) patients who were overweight and obese. METHODS: This study was a single-blind, RCT conducted at Teaching Bay of Rehmatul-Lil-Alameen Post Graduate Institute of Cardiology between February and November 2020. 114 knee OA patients who were overweight and obese were randomly divided by a computer-generated number into the rehabilitation group with mHealth (RGw-mHealth) to receive LLRP + instructions of daily care (IDC) combined with mHealth intervention, rehabilitation group without mHealth (RGwo-mHealth) to receive LLRP + IDC intervention and control group (CG) to receive IDC intervention. All three groups were also provided leaflets explaining about their intervention. The primary outcome measure was knee pain measured by the Western Ontario and McMaster Universities Osteoarthritis Index score. The secondary outcome measures were mobility measured by the Timed up and go (TUG) test, functional activity measured by the patient-specific functional scale (PSFS), and ADL measured by the Katz Index of independence in ADL scores. RESULTS: Among the 114 patients who were randomized (mean age, 53 years), 96 (84%) completed the trial. After 3-months of intervention, patients in all three groups had statistically significant knee pain reduction (RGw-mHealth: 2.54; RGwo-mHealth: 1.47; and CG: 0.37) within groups (P < 0.05). Furthermore, patients in the RGw-mHealth and RGwo-mHealth had statistically significant improvement in mobility, functional activity, and ADL within groups (P < 0.05), but no improvement was noted in the CG (p > 0.05). As indicated in the overall analysis of covariance, there were statistically significant differences in the mean knee pain, mobility, functional activity, and ADL changes between groups after 3-months (p < 0.001). The pairwise between-group comparisons (Bonferroni post hoc analysis) of the knee pain, mobility, functional activity, and ADL scores at 3-months revealed that patients in the RGw-mHealth had significantly higher mean change in the knee pain, TUG test, functional activity, and ADL scores compared to patients in the RGwo-mHealth or CG. CONCLUSION: Reduction in knee pain, improvement in mobility, functional activity, and ADL were more among patients in the RGw-mHealth compared with the RGwo-mHealth or CG. Trial registration National Medical Research Registry: NMRR-20-1094-52911. Date of registration: 05-05-2020. URL: https://www.nmrr.gov.my .

Effect of Progressive Resistance Strength Training on Body Mass Index, Quality of Life and Functional Capacity in Knee Osteoarthritis: A Randomized Controlled Trial.

PURPOSE: This study aimed to investigate the effectiveness of progressive resistance strength training of the lower limb rehabilitation protocol (LLRP) on body mass index (BMI), quality of life, and functional capacity in patients with knee osteoarthritis (OA) who were overweight and obese. PATIENTS AND METHODS: Fifty-six patients were allocated into either the Rehabilitation Protocol Group (RPG) or the Control Group (CG) by a computer-generated random number. The patients in the RPG performed the strengthening exercises of the LLRP and followed the instruction of daily care (IDC). The patients in the CG only followed the IDC as a usual care. Gait Speed Test, quality of life, and BMI were taken at pre-test and post-test measurements. Paired samples t-test and two way mixed analysis of variance were used to analyze the change of BMI within and compare the difference of BMI between the groups, respectively. Wilcoxon signed ranked test and Mann-Whitney U-test were used to analyze the changes of quality of life and functional capacity within and compare the differences of quality of life and functional capacity between the groups, respectively. RESULTS: The patients in the RPG reported a significant reduction in BMI (p = 0.025), improvement in quality of life (p ≤ 0.001), and functional capacity (p ≤ 0.001) within group. The patients in the CG also reported a significant improvements in quality of life (p < 0.05). The improvement in quality of life score was greater in the patients with RPG than the CG (p = 0.053). CONCLUSION: The progressive resistance strength training of LLRP is effective in terms of reducing BMI, improving quality of life and functional capacity. TRIAL REGISTRATION: Name: Iranian Registry of Clinical Trials. Number: IRCT20191221045846N3. Enrollment of first participant: 27-07-2020.

Health risk assessment of hexachlorocyclohexane in soil, water and plants in the agricultural area of Potohar region, Punjab, Pakistan.

In this study analysis of soil, water and plant residue samples is presented to evaluate the contamination levels and possible health risks. Hexachlorocyclohexane (HCH) is a persistent organic pollutant used as a pesticide in agricultural sector for pest control in order to obtain higher productivity. For analysis soil, water and crop residue samples were collected from different agricultural areas of the northern Punjab region of Pakistan. The investigation of the samples shows significant levels of HCH residues in all types of samples. Gas chromatography-mass spectrometry analysis was used to assess the higher residue levels of HCH in the samples. The concentration of HCH residues detected in samples ranged from 2.43 to 8.88 µg/g in soil, nd -5.87 µg/l in water and nd - 4.87 µg/g in plants. The presence of HCH residues in soil, water and plant samples was beyond the recommended quality guidelines. Human health risk was evaluated for cancer and non-cancer risks through dietary and non-dietary exposure routes. The hazard index was HI > 1 in children and HI < 1 in adults, while the non-dietary incremental lifetime cancer risks (ILCR) were beyond the internationally acceptable limit of 1 × 10-5. Hence, results of the present investigation concluded the presence of high levels of HCH residues in samples and pose high health risk to the inhabitants. These findings are alarming and apprise the concerned departments for the remediation of contamination and proper implementation of environmental laws in the area.

Short-Term Effects of Strengthening Exercises of the Lower Limb Rehabilitation Protocol on Pain, Stiffness, Physical Function, and Body Mass Index among Knee Osteoarthritis Participants Who Were Overweight or Obese: A Clinical Trial.

BACKGROUND: Osteoarthritis (OA) of the knee is defined as a progressive disease of the synovial joints and is characterized by wear and tear of the cartilage and underlying bone. This study aimed to determine the short-term effects of the lower limb rehabilitation protocol (LLRP) on pain, stiffness, physical function, and body mass index (BMI) among knee OA participants who were overweight or obese. Methodology. A single-blinded randomized controlled trial of one-month duration was conducted at Rehmatul-Lil-Alameen Postgraduate Institute, Lahore, Pakistan. Fifty overweight or obese participants with knee OA were randomly divided into two groups by a computer-generated number. Participants in the rehabilitation protocol group (RPG) were provided with leaflets explaining the strengthening exercises of the LLRP and instruction of daily care (IDC), while the participants in the control group (CG) were provided with leaflets explaining the IDC only for a duration of four weeks. The primary outcome measures were the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores for pain, stiffness, and physical function. The secondary outcome measures were BMI, exercise adherence, and patients' satisfaction assessed by using the numeric rating scale ranging from 0 to 10. The paired-sample t-test was used to analyze the differences within groups from baseline to posttest evaluations. The analysis of variance 2 × 2 factor was used to analyze the differences in BMI, knee pain, stiffness, and physical function between the groups. RESULTS: Participants in the RPG and CG reported a statistically significant reduction in knee pain and stiffness (p ≤ 0.05) within the group. The reduction in the scores of knee pain was higher in participants in the RPG than that in participants in the CG (p=0.001). Additionally, participants in the RPG reported greater satisfaction (p=0.001) and higher self-reported exercise adherence (p=0.010) and coordinator-reported exercise adherence (p=0.046) than the participants in the CG. CONCLUSION: Short-term effects of the LLRP appear to reduce knee pain and stiffness only, but not physical function and BMI.

Cadmium level and soil type played a selective role in the endophytic bacterial community of hyperaccumulator Sedum alfredii Hance.

Phytoremediation technology has been applied for heavy metal elimination for many years, however little research about the difference of remediation efficiency of hyperaccumulator in different soils was reported. Here, a pot experiment was conducted with a cadmium (Cd)/zinc hyperaccumulator Sedum alfredii Hance grown on different types of soils and the differences of its endophytic bacterial community were elucidated. The results showed that the biomass of S. alfredii grown on black soil under both low and high Cd treatment was much heavier than that grown on other soils, and Cd uptake and Cd accumulation of S. alfredii in paddy soil was the highest, suggesting that black soil was more suitable for S. alfredii growth while paddy soil was more efficient for Cd phytoextraction. Moreover, Cd treated level and soil type both affected the structure of plant endophytic bacterial community. The two shared genera in the four representative soils were Caulobacter and Acinetobacter under low Cd level, and Caulobacter and Lactobacillus under high Cd level. Cd treatment shifted the structure and abundance of plant endophytes in different types of soils, while black soil and paddy soil were more similar in the distribution and abundance of S. alfredii endophytic community. This study highlighted the understanding of response to Cd within S. alfredii endophytic community in different types of soils, which could be beneficial for enhanced phytoremediation efficiency and better S. alfredii cultivation.

The effect of rehabilitation protocol using mobile health in overweight and obese patients with knee osteoarthritis: a clinical trial

Abstract Objective: The objective of this randomized controlled trial (RCT) was to investigate the effectiveness of the lower limb rehabilitation protocol (LLRP) combined with mobile health (mHealth) applications on knee pain, mobility, functional activity and activities of daily living (ADL) among knee osteoarthritis (OA) patients who were overweight and obese. Methods: This study was a single-blind, RCT conducted at Teaching Bay of Rehmatul-Lil-Alameen Post Graduate Institute of Cardiology between February and November 2020. 114 knee OA patients who were overweight and obese were randomly divided by a computer-generated number into the rehabilitation group with mHealth (RGw-mHealth) to receive LLRP + instructions of daily care (IDC) combined with mHealth intervention, rehabilitation group without mHealth (RGwo-mHealth) to receive LLRP + IDC intervention and control group (CG) to receive IDC intervention. All three groups were also provided leaflets explaining about their intervention. The primary outcome measure was knee pain measured by the Western Ontario and McMaster Universities Osteoarthritis Index score. The secondary outcome measures were mobility measured by the Timed up and go (TUG) test, functional activity measured by the patient-specific functional scale (PSFS), and ADL measured by the Katz Index of independence in ADL scores. Results: Among the 114 patients who were randomized (mean age, 53 years), 96 (84%) completed the trial. After 3-months of intervention, patients in all three groups had statistically significant knee pain reduction (RGw-mHealth: 2.54; RGwo-mHealth: 1.47; and CG: 0.37) within groups ( P < 0.05). Furthermore, patients in the RGw-mHealth and RGwo-mHealth had statistically significant improvement in mobility, functional activity, and ADL within groups ( P < 0.05), but no improvement was noted in the CG ( p > 0.05). As indicated in the overall analysis of covariance, there were statistically significant differences in the mean knee pain, mobility, functional activity, and ADL changes between groups after 3-months ( p < 0.001). The pairwise between-group comparisons (Bonferroni post hoc analysis) of the knee pain, mobility, functional activity, and ADL scores at 3-months revealed that patients in the RGw-mHealth had significantly higher mean change in the knee pain, TUG test, functional activity, and ADL scores compared to patients in the RGwo-mHealth or CG. Conclusion: Reduction in knee pain, improvement in mobility, functional activity, and ADL were more among patients in the RGw-mHealth compared with the RGwo-mHealth or CG. Trial registration National Medical Research Registry: NMRR-20-1094-52911. Date of registration: 05-05-2020. URL: https://www.nmrr.gov.my.

Biochar amendment improves alpine meadows growth and soil health in Tibetan plateau over a three year period.

Previous biochar research has primarily focused on agricultural annual cropping systems with very little attention given to highly fragile, complex and diverse natural alpine grassland ecosystems. The present study investigated the effect of biochar on the growth of alpine meadows and soil health. This study was conducted in the Qinghai Tibetan Plateau over a three year period to investigate the effect of three rice husk biochar application rates alone and combination with high and low NPK fertilizer dosages on alpine meadow productivity, soil microbial diversity as well as pH, carbon and nitrogen content at 0-10 cm and 10-20 cm depth. At the end of the 3rd year soil samples were analysed and assessed by combined analysis of variance. The results showed that biochar application in combination with nitrogen (N), phosphorus (P) and potassium (K) fertilizer had a significant increase in fresh and dry biomass during the second and third year of the study as compared to control and alone biochar application (p ≤ 0.05). Biochar alone and in combination with NPK fertilizer resulted in a significant increase in the soil pH and carbon contents of the soil. XPS results, the SEM imaging and EDS analysis of aged biochar demonstrated that the biochar has undergone complex changes over the 3 years as compared to fresh biochar. This research suggests that biochar has positive effect on alpine meadow growth and soil health and may be an effective tool for alpine meadow restoration.

Biochar alleviates Cd phytotoxicity by minimizing bioavailability and oxidative stress in pak choi (Brassica chinensis L.) cultivated in Cd-polluted soil.

The production of leafy vegetables such as Brassica chinensis L. in cadmium (Cd)-polluted soil causes serious threats to human health and food safety around the globe. A pot culture was established to examine the efficacy of rice-straw induced biochar (applied to soil at the rate of 0%, 2.5% and 5%, w/w) on growth, gaseous exchange attributes, antioxidative capacities and Cd uptake in pak choi (Brassica chinensis L.), when soil was spiked with Cd (CdCl2) at 0, 5, 10 and 20 mg kg-1 soil. The results revealed that Cd stress significantly (P < 0.05) reduced plant biomass and physiological attributes, and accumulated higher Cd concentrations in plant tissues with the increasing rate of Cd concentration in the soil. However, incorporation of biochar at 5% application rate prominently increased the shoot (98.27%) and root (85.96%) dry biomass, net photosynthesis (45.52%), transpiration rate (161.34%), stomatal activity (111.76%) and intracellular CO2 concentration (32.25%) when Cd was added at 20 mg kg-1 soil, relative to the respective treatment without biochar. Whereas, incorporation of biochar at 5% significantly reduced the bioavailable Cd by 16.64% under 20 mg kg-1 soil, compared to respective Cd treatment without biochar.Similarly, Cd accumulation in shoots and roots was decreased by 42.49% and 29.23%, and thereby reduced leaf MDA and H2O2 contents by 21.45% and 31.28%, respectively, at 20 mg Cd kg-1 spiked soil relative to without biochar amended soil. An increment was noticed in the activities of guaiacol peroxidase (POD), superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and glutathione (GSH) by 37.31%, 66.35%, 115.94%, 122.72% and 59.96%, respectively, with 5% biochar addition in 20 mg kg-1 Cd spiked soil. Moreover, biochar induced a synergistic impact on plants by increasing soil alkalinization and thereby reducing Cd phytotoxicity throughimmobilization. Overall, results proposed that rice-straw biochar has an ability to restore Cd polluted soil and increased pak choi production and thereby reduced food security risks in polluted soil.

Effects of elevated CO2 and endophytic bacterium on photosynthetic characteristics and cadmium accumulation in Sedum alfredii.

Elevated CO2 and use of endophytic microorganisms have been considered as efficient and novel ways to improve phytoextraction efficiency. However, the interactive effects of elevated CO2 and endophytes on hyperaccumulator is poorly understood. In this study, a hydroponics experiment was conducted to investigate the combined effect of elevated CO2 (eCO2) and inoculation with endophyte SaMR12 (ES) on the photosynthetic characteristics and cadmium (Cd) accumulation in hyperaccumulator Sedum alfredii. The results showed that eCO2 × ES interaction promoted the growth of S. alfredii, shoot and root biomass net increment were increased by 264.7 and 392.3%, respectively, as compared with plants grown in ambient CO2 (aCO2). The interaction of eCO2 and ES significantly (P < 0.05) increased chlorophyll content (53.2%), Pn (111.6%), Pnmax (59.8%), AQY (65.1%), and Lsp (28.8%), but reduced Gs, Tr, Rd, and Lcp. Increased photosynthetic efficiency was associated with higher activities of rubisco, Ca2+-ATPase, and Mg2+-ATPase, and linked with over-expression of two photosystem related genes (SaPsbS and SaLhcb2). PS II activities were significantly (P < 0.05) enhanced with Fv/Fm and Φ(II) increased by 12.3 and 13.0%, respectively, compared with plants grown in aCO2. In addition, the net uptake of Cd in the shoot and root tissue of S. alfredii grown in eCO2 × ES treatment was increased by 260.7 and 434.9%, respectively, due to increased expression of SaHMA2 and SaCAX2 Cd transporter genes. Our results suggest that eCO2 × ES can promote the growth of S. alfredii due to increased photosynthetic efficiency, and improve Cd accumulation and showed considerable potential of improving the phytoextraction ability of Cd by S. alfredii.

Influence of Pyrolysis Temperature on Physico-Chemical Properties of Corn Stover (Zea mays L.) Biochar and Feasibility for Carbon Capture and Energy Balance.

This study examined the influence of pyrolysis temperature on biochar characteristics and evaluated its suitability for carbon capture and energy production. Biochar was produced from corn stover using slow pyrolysis at 300, 400 and 500°C and 2 hrs holding time. The experimental biochars were characterized by elemental analysis, BET, FTIR, TGA/DTA, NMR (C-13). Higher heating value (HHV) of feedstock and biochars was measured using bomb calorimeter. Results show that carbon content of corn stover biochar increased from 45.5% to 64.5%, with increasing pyrolysis temperatures. A decrease in H:C and O:C ratios as well as volatile matter, coupled with increase in the concentration of aromatic carbon in the biochar as determined by FTIR and NMR (C-13) demonstrates a higher biochar carbon stability at 500°C. It was estimated that corn stover pyrolysed at 500°C could provide of 10.12 MJ/kg thermal energy. Pyrolysis is therefore a potential technology with its carbon-negative, energy positive and soil amendment benefits thus creating win- win scenario.

In Vitro Assessment of Cadmium Bioavailability in Chinese Cabbage Grown on Different Soils and Its Toxic Effects on Human Health.

The minimum concentration of cadmium (Cd), by Chinese cabbage grown on Cd contaminated soils that can initiate toxicity in human liver cells using in vitro digestion coupled with Caco-2/HL-7702 cell models was studied. Cadmium bioaccessibility in the gastric phase for yellow soil (YS) cabbage (40.84%) and calcareous soil (CS) cabbage (21.54%) was significantly higher than small intestinal phase with the corresponding values of 21.2% and 11.11%, respectively. Cadmium bioavailability was higher in YS cabbage (5.27%-14.66%) than in CS cabbage (1.12%-9.64%). Cadmium concentrations (>0.74 µg) transported from YS and CS cabbage were able to induce oxidative (MDA, H2O2) stress by inhibiting antioxidant (SOD, GPx) enzyme activities in human liver cells (HL-7702). Additionally the study revealed that the ingestion of Cd contaminated Chinese cabbage grown in acidic soil (yellow soil) weakened the antioxidant defense system under all levels of contamination (2, 6, and 9 mg·kg(-1)) which ultimately escalated the oxidative stress in liver cells; however, in case of CS cabbage, a marked oxidative stress was observed only at 9 mg kg(-1) Cd level of soil. Therefore, it is necessary to monitor Cd concentrations in leafy vegetables grown on acidic soils to minimize human health risk.