Sustained High Nutrient Supply As an Allelopathic Trigger between Periphytic Biofilm and Microcystis aeruginosa.

Allelopathy among aquatic organisms, especially microorganisms, has received growing attention in recent years for its role in shaping interactions with bloom-forming algae. Many studies have shown that allelopathy occurs and increases under nutrient limiting conditions. However, to date there is no reported direct evidence to indicate that allelopathy occurs under the condition of constant high nutrient supply. Here we report the allelopathic action of periphytic biofilm on bloom-forming cyanobacteria (Microcystis aeruginosa), which was triggered by the stress of high nutrient conditions, and continues while nutrients are maintained at high levels (trophic state index at 159 and 171). The experimental evidence indicates that the electron transport from photosystem II (PS II) to photosystem I (PS I) in M. aeruginosa is interrupted by the identified allelochemicals, (9Z)-Octadec-9-enoic acid and (9Z)-Hexadec-9-enoic acid, leading to the failure of photosynthesis and the subsequent death of M. aeruginosa. Our findings indicate that the nutrient stress of constant high nutrient supply may be a newly recognized trigger causing allelopathy between microbial competitors, and therefore opening a new direction for the better management of ecological processes in cyanobacteria-dominated and hyper-eutrophic waters.

Olive (Olea europaea L.) Biophenols: A Nutriceutical against Oxidative Stress in SH-SY5Y Cells.

Plant biophenols have been shown to be effective in the modulation of Alzheimer's disease (AD) pathology resulting from free radical-induced oxidative stress and imbalance of the redox chemistry of transition metal ions (e.g., iron and copper). On the basis of earlier reported pharmacological activities, olive biophenols would also be expected to have anti-Alzheimer's activity. In the present study, the antioxidant activity of individual olive biophenols (viz. caffeic acid, hydroxytyrosol, oleuropein, verbascoside, quercetin, rutin and luteolin) were evaluated using superoxide radical scavenging activity (SOR), hydrogen peroxide (H2O2) scavenging activity, and ferric reducing ability of plasma (FRAP) assays. The identification and antioxidant activities in four commercial olive extracts-Olive leaf extractTM (OLE), Olive fruit extractTM (OFE), Hydroxytyrosol ExtremeTM (HTE), and Olivenol plusTM (OLP)-were evaluated using an on-line HPLC-ABTS•+ assay, and HPLC-DAD-MS analysis. Oleuropein and hydroxytyrosol were the predominant biophenols in all the extracts. Among the single compounds examined, quercetin (EC50: 93.97 µM) and verbascoside (EC50: 0.66 mM) were the most potent SOR and H2O2 scavengers respectively. However, OLE and HTE were the highest SOR (EC50: 1.89 µg/mL) and H2O2 (EC50: 115.8 µg/mL) scavengers among the biophenol extracts. The neuroprotection of the biophenols was evaluated against H2O2-induced oxidative stress and copper (Cu)-induced toxicity in neuroblastoma (SH-SY5Y) cells. The highest neuroprotection values (98% and 92%) against H2O2-induced and Cu-induced toxicities were shown by the commercial extract HTETM. These were followed by the individual biophenols, caffeic acid (77% and 64%) and verbascoside (71% and 72%). Our results suggest that olive biophenols potentially serve as agents for the prevention of neurodegenerative diseases such as AD, and other neurodegenerative ailments that are caused by oxidative stress.

Attenuating Colorectal Cancer Using Nine Cultivars of Australian Lupin Seeds: Apoptosis Induction Triggered by Mitochondrial Reactive Oxygen Species Generation and Caspases-3/7 Activation.

As Australian lupin cultivars are rich sources of polyphenols, dietary fibers, high-quality proteins, and abundant bioactive compounds with significant antioxidant, antidiabetic, and anticancer activities, this research work is aimed at investigating the colon cancer alleviation activity of nine cultivars of lupin seeds on HCT116 and HT29 colon carcinoma cell lines through anti-proliferation assay, measurement of apoptosis, and identification of the mechanism of apoptosis. Nine cultivars were pre-screened for anti-proliferation of HCT116 and HT29 cells along with consideration of the impact of heat processing on cancer cell viability. Mandelup and Jurien showed significant inhibition of HCT116 cells, whereas the highest inhibition of HT29 cell proliferation was attained by Jurien and Mandelup. Processing decreased the anti-proliferation activity drastically. Lupin cultivars Mandelup, Barlock, and Jurien (dose: 300 µg/mL) induced early and late apoptosis of colon cancer cells in Annexin V-FITC assay. The mechanism of apoptosis was explored, which involves boosting of caspases-3/7 activation and intracellular reactive oxygen species (ROS) generation in HCT116 cells (Mandelup and Barlock) and HT29 cells (Jurien and Mandelup). Thus, the findings showed that lupin cultivars arrest cell cycles by inducing apoptosis of colorectal carcinoma cells triggered by elevated ROS generation and caspases-3/7 activation.

In Silico, In Vitro, and In Vivo Evaluation of Caffeine-Coated Nanoparticles as a Promising Therapeutic Avenue for AML through NF-Kappa B and TRAIL Pathways Modulation.

BACKGROUND: Advancements in nanoscience have led to a profound paradigm shift in the therapeutic applications of medicinally important natural drugs. The goal of this research is to develop a nano-natural product for efficient cancer treatment. METHODS AND RESULTS: For this purpose, mesoporous silica nanoparticles (MSNPs) were formulated, characterized, and loaded with caffeine to develop a targeted drug delivery system, i.e., caffeine-coated nanoparticles (CcNPs). In silico docking studies were conducted to examine the binding efficiency of the CcNPs with different apoptotic targets followed by in vitro and in vivo bioassays in respective animal models. Caffeine, administered both as a free drug and in nanomedicine form, along with doxorubicin, was delivered intravenously to a benzene-induced AML model. The anti-leukemic potential was assessed through hematological profiling, enzymatic biomarker analysis, and RT-PCR examination of genetic alterations in leukemia markers. Docking studies show strong inter-molecular interactions between CcNPs and apoptotic markers. In vitro analysis exhibits statistically significant antioxidant activity, whereas in vivo analysis exhibits normalization of the genetic expression of leukemia biomarkers STMN1 and S1009A, accompanied by the restoration of the hematological and morphological traits of leukemic blood cells in nanomedicine-treated rats. Likewise, a substantial improvement in hepatic and renal biomarkers is also observed. In addition to these findings, the nanomedicine successfully normalizes the elevated expression of GAPDH and mTOR induced by exposure to benzene. Further, the nanomedicine downregulates pro-survival components of the NF-kappa B pathway and upregulated P53 expression. Additionally, in the TRAIL pathway, it enhances the expression of pro-apoptotic players TRAIL and DR5 and downregulates the anti-apoptotic protein cFLIP. CONCLUSIONS: Our data suggest that MSNPs loaded with caffeine, i.e., CcNP/nanomedicine, can potentially inhibit transformed cell proliferation and induce pro-apoptotic TRAIL machinery to counter benzene-induced leukemia. These results render our nanomedicine as a potentially excellent therapeutic agent against AML.

A novel biotechnology based on periphytic biofilms with N-acyl-homoserine-lactones stimulation and lanthanum loading for phosphorus recovery.

This study presents an approach for developing periphytic biofilm with N-acyl-homoserine-lactones (AHLs) stimulation and lanthanum (La, a rare earth element) loading, to achieve highly efficient and stable phosphorus (P) recovery from wastewater. AHLs stimulated biofilm growth and formation, also improved stable P entrapment by enhancing extracellular polymeric substance (EPS) production and optimizing P-entrapment bacterial communities. Periphytic biofilms loading La is based on ligand exchanges, and La loading achieved initial rapid P entrapment by surface adsorption. The combination of AHLs stimulation and La loading achieved 99.0% P entrapment. Interestingly, the enhanced EPS production stimulated by AHLs protected biofilms against La. Moreover, a method for P and La separately recovery from biofilms was developed, achieving 89-96% of P and 88-93% of La recovery. This study offers a promising biotechnology to reuse La from La-rich wastewater and recover P by biofilm doped with La, which results in a win-win situation for resource sustainability.

Investigations of AGEs' inhibitory and nephroprotective potential of ursolic acid towards reduction of diabetic complications.

In diabetes, interactions between AGEs (advanced glycation end products) and RAGEs (receptors of AGEs) are responsible for chronic complications and the current work reports the potential of ursolic acid as a RAGE inhibitor. The three-dimensional crystal structure of RAGE was first docked with target molecules by 'AutodockVina' using GROMOS 96 4381 parameters. Druggability and pharmacokinetic properties were calculated from the SwissADME server. In vitro bovine serum albumin (BSA)-glucose fluorescence and BSA-methylglyoxal fluorescence assays were also performed. Finally, alloxan-induced diabetic mice were administered ursolic acid and metformin standards (at 1, 50, 100 mg/kg) for 50 days. Blood glucose levels, several blood parameters, blood lipid profiles, supernatants of homogenized kidney and plasma of mice were examined. In the computational study, ursolic acid showed greater binding affinity (-7.5 kcal/mol) for RAGE with an ADMET profiles and lead-likeness compared to metformin as a standard antidiabetic. In the in vitro fluorescence assays, the IC50 value for ursolic acid was much less than that of metformin standard. During the in vivo study, significant reduction in the levels of blood glucose, HbA1C (glycated hemoglobin), creatinine, uric acid, BUN (blood urea nitrogen), AST (aspartate aminotransferase), ALT (alanine aminotransferase), ALP (alkaline phosphatase) were observed in the ursolic acid and metformin-treated mice. Substantial inhibition of AGEs' formation in the plasma and kidney were also detected. Finally, the histopathological examinations of the kidney revealed reversal of cellular necrosis. Hence, ursolic acid is proved to be a potent AGE inhibitory agent in managing the diabetic complications.

Enhanced periphyton biodegradation of endocrine disrupting hormones and microplastic: Intrinsic reaction mechanism, influential humic acid and microbial community structure elucidation.

Endocrine-disrupting compounds (EDCs), as well as microplastics, have drawn global attention due to their presence in the aquatic ecosystem and persistence in wastewater treatment plants (WWTPs). In the present study, for simultaneous bio-removal of two EDCs, 17α-ethinylestradiol (EE2), bisphenol A (BPA), and a microplastic, polypropylene (PP) four kinds of periphytic biofilms were employed. Additionally, the effect of humic acid (HA) on the removal efficacy of these biofilms was evaluated. It was observed that EE2 and BPA (0.2 mg L-1 each) were completely (∼100%) removed within 36 days of treatment; and the biodegradation of EE2, BPA, and PP was significantly enhanced in the presence of HA. Biodegradation of EE2 and BPA was evaluated through Ultra-high performance liquid chromatography (UHPLC), and Gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) was used to determine the mechanism of degradation. Gel permeation chromatography (GPC) and SEM had validated the biodegradation of PP (5.2-14.7%). MiSeqsequencing showed that the community structure of natural biofilm changed after the addition of HA, as well as after the addition of EDCs and PP. This change in community structure might be a key factor regarding variable biodegradation percentages. The present study revealed the potential of periphytic biofilms for the simultaneous removal of pollutants of different chemical natures, thus provides a promising new method for wastewater treatment applications.

The decoction of radix Astragali inhibits the growth of Microcystis aeruginosa.

Many measures have been developed to control the harmful algal blooms that are potentially threatening potable waters. The pilot experiments showed that the unfiltered and the sterile-filtered decoctions of radix Astragali inhibited the growth of Microcystis aeruginosa. The inhibitory effect diminished in natural pond conditions after 68 days, due to photo-degradation of the flavonoids from radix Astragali that appear to be responsible for the action on M. aeruginosa. Four phases (assemblage, conglomeration, cell membrane destruction and decomposition) can be characterized in the process of cell death with increasing decoction dose. The quantum yields and electron transport rates of photosynthesis system II of M. aeruginosa cells markedly decreased during contact with the decoction, resulting in the disruption of M. aeruginosa photosynthesis. The results indicate that the application of radix Astragali decoction for the inhibition of M. aeruginosa growth is feasible when the dose is less than 20 ml L(-1).

Interactions between periphytic biofilms and dissolved organic matter at soil-water interface and the consequent effects on soil phosphorus fraction changes.

Dissolved organic matter (DOM) plays vital roles in carbon and other nutrient transformation at soil-water interfaces (SWI) in paddy fields. It is associated with the growth and withering of periphytic biofilms. However, the interactions between DOM and periphytic biofilms remain largely unknown. In this study, a microcosm experiment with different initial DOM contents elucidated that the biomass, and biomass nitrogen and phosphorus contents were greatly influenced by humic-like substances (C2 and C3), while the growth of periphytic biofilms increased the contents of humic-like (C1 and C2) and tryptophan-like substances (C5) in soil. Moreover, the decomposition of periphytic biofilms significantly increased soil pH, DOM, C2, C3 and C5 contents, but caused decrease in Eh, with consequent reduce in water soluble phosphorus (WSP) and release of algal available phosphorus (AAP). Results from this study revealed how DOM interacts with periphytic biofilms and the consequent effects on changes of bioactive phosphorus fractions, and provide practical information for designing periphytic biofilm based biofertilizer from the perspective of soil DOM.

Antidiabetic profiling, cytotoxicity and acute toxicity evaluation of aerial parts of Phragmites karka (Retz.).

ETHNOPHARMACOLOGICAL RELEVANCE: Phragmites karka (Retz.) of family Poaceae is a pristine tropical plant that is well known to the local healers for ailments of diabetes, fever, diarrhea and CNS depression but lacks the scientific evidence behind its traditional usage. Hence, we explicated this plant to find the scientific basis of its traditional utilization. AIM OF THE STUDY: The current study aims to find out the antidiabetic potential, toxicity after oral administration and in vitro cytotoxic activity of aerial parts of the plant on HeLa cells. METHODS: The plant was extracted with methanol by maceration and the crude extract was then subjected to solvent partitioning with modified Kupchan method for preparing several fractions. Phytochemical screening and total phenolic content of the plant was first determined through established procedures. Acute toxicity of the plant was studied by orally administering a single high dose (5000 mg/kg) of drug. Cytotoxicity of the methanolic plant extract was determined by measuring the percentage of cell viability on human cervical cancer cell lines, HeLa. In vitro antidiabetic activity was determined through iodine starch and DNSA (3,5-dinitrosalicylic acid) method of α-amylase inhibition. Finally, in vivo oral glucose tolerance test and alloxan induced antidiabetic activity test was performed at 150 and 300 mg/kg body weight doses of plant extract to confirm the in vivo antidiabetic activity. RESULTS: No mortality was demonstrated by Phragmites karka in the acute toxicity test. However, signs of cellular toxicity was observed and histopathological studies on major organs exhibited necrosis in liver and kidney. In vitro cytotoxicity assay revealed the death of HeLa cells by DCM (dichloromethane) and n-hexane fractions of plant extract at 100 and 10 µg/mL concentrations. The IC50 value of the fractions were later evaluated by MTT assay (316.1 and 96.7 µg/mL for n-hexane and DCM fractions, respectively). In the iodine starch and DNSA method of α-amylase enzyme inhibitory activity test, substantial inhibition of enzyme was observed with the IC50 values of 2.05 and 2.08 mg/mL, respectively. In the in vivo antidiabetic activity test, considerable reduction in blood glucose level of diabetic mice was detected in both oral glucose tolerance test and alloxan induced antidiabetic activity test. In addition, the microscopic examination of pancreas showed noticeable recovery of pancreatic ß cells and the blood lipid profile analysis represented a significant (p < 0.05) reduction of total cholesterol, LDL (low density lipoprotein) and triglyceride level in plant extract treated mice. CONCLUSION: Results of this study reveals that the Phragmites karka extract is toxic at cellular level after oral administration and cytotoxic when tested on HeLa cells. The plant also evidenced hypoglycemic property, possibly through the inhibition of α-amylase enzyme and recovered the pancreatic beta cells along with the improvement of lipid profile of diabetic mice. However, robust studies on this plant is required to isolate the bioactive compounds, elucidate structures and evaluate their mechanism of actions in support of our findings. CLASSIFICATION: Toxicology and Safety, Quality Traditional Medicine.

Electron transport, light energy conversion and proteomic responses of periphyton in photosynthesis under exposure to AgNPs.

Silver nanoparticles (AgNPs) including a mix of intact nanoparticle-Ag and 'free' Ag+ pose high risks to benthic photoautotrophs, but the photosynthetic responses of benthic microbial aggregates to AgNPs still remain largely unknown. Here, periphyton and Nostoc were used to elucidate the photosynthetic responses of benthic algae community to intact nanoparticle-Ag and Ag+. During exposure, both intact nanoparticle-Ag and Ag+ imposed negative effects on photosynthesis of benthic algae, but via different pathways. Specifically, Ag+ had stronger effects on damaging the oxygen-evolving complex (OEC) and thylakoid membrane than intact nanoparticle-Ag. Ag+ also suppressed electron transfer from QA to QB, and impaired phycobilisome. Intact nanoparticle-Ag inhibited the expression of PsbD and PsbL in PSII, but prompted the ROS scavenging capacity. In response to the stress of AgNPs, the benthic algae increased light energy absorption to maintain the electron transport efficiency, and up-regulated PSI reaction center protein (PsaA) to compensate the degraded PSII. These results reveal how intact nanoparticle-Ag and Ag+ influence electron transport, energy conversion and protein expression in the photosynthesis of periphyton, and provide deep insights into the responses of benthic photoautotrophs to different components of AgNPs.

Comparative assessment of nutritional, thermal, rheological and functional properties of nine Australian lupin cultivars.

Lupin holds an important place among the legumes and the utilization of lupin as a dietary protein source is an excellent environmentally friendly alternative to animal-based products for human nutrition. In the present study, nutritional, thermal, rheological and functional properties of nine Australian lupin cultivars have been assayed in order to find the most valuable one, both nutritiously and industrially. The set comprised six Lupinus angustifolius L. viz., Barlock, Gunyadi, Jenabillup, Jindalee, Jurien, Mandelup and three Lupinus albus L. viz., Luxor, Rosetta, WK388 cultivars. The tests included analysis of color, macronutrient and micronutrient composition, pasting, textural and thermal properties, electrophoretic profile of protein isolates, swelling power, water and oil absorption capacity, emulsifying capacity, emulsion stability, creaming stability, foaming capacity and stability of the cultivars' dehulled seed flours. The results indicated substantial variation in macro and micro-nutritional value as well as satisfactory swelling ability, solubility, surface hydrophobicity, foaming ability, emulsifying capacity and gelation property of lupin flours. Superior nutritional, thermal, rheological and functional potential was demonstrated by the L. albus cultivars compared to the L. angustifolius cultivars with the exception of Mandelup.

Identification of bioactive metabolites and evaluation of in vitro anti-inflammatory and in vivo antinociceptive and antiarthritic activities of endophyte fungi isolated from Elaeocarpus floribundus blume.

ETHNOPHARMACOLOGICAL RELEVANCE: Functional disability associated with rheumatoid arthritis (RA), a chronic inflammatory autoimmune disease is a challenging concern in healthcare systems. Along with environmental factors and epigenetic disorders, multiple pathways are reported as prominent mechanism for the progression of RA symptoms including; pain, swelling and stiffness of joints. Elaeocarpus floribundus Blume has been used as a folklore medicine for RA from ancient times. This plant harbours a suite of endophytic fungi that produce a range of metabolites of potential interest. Thus, for the establishment of a scientific basis for this folklore use, it is essential to find out the involvement, if any, of the endophytic fungi living in this plant and the metabolites they elaborate, for the management of RA. AIM OF THE STUDY: This study was designed to isolate, identify and evaluate the in vitro anti-inflammatory and in vivo antinociceptive and antiarthritic activities of the compounds produced by the endophytic fungi living in different parts of Elaeocarpus floribundus Blume. MATERIALS AND METHODS: Endophytic fungi from different parts of the plant were isolated and cultured for the production of secondary metabolites. Chromatographically fractionated fungal extracts were assessed for anti-inflammatory and antinociceptive activities. For the evaluation of anti-inflammatory activity, in vitro cyclooxygenase (COX1/COX2) and 5-lipoxygenase (5-LOX) inhibitory assays were performed. For the evaluation of in vivo antinociceptive activity, hot plate acetic acid induced writhing, and formalin induced paw licking methods were adopted, whereas complete Freund's adjuvant (CFA) induced poly-arthritic method was adopted for the evaluation of antiarthritic activity. The most effective fraction was analyzed by liquid chromatography-mass spectroscopy (LC-MS) in search of the bioactive extracellular metabolites. RESULTS: Five endophytic fungi viz. Aspergillus fumigatus, Aspergillus niger, Rhizoctonia oryzae, Rhizopus oryzae, and Syncephalastrum racemosum were isolated. COX1/COX2 and 5-LOX inhibitory assays state that the Aspergillus niger fraction possesses the greatest activity against these enzymes of inflammatory process. In vivo antinociceptive showed significant (***P<0.001) reduction of pain in a dose dependent manner. As well, significant (***P<0.001) reduction of paw volume was observed in CFA induce poly-arthritic test. LC/MS analysis of the Aspergillus niger fraction revealed the presence of bioactive compounds including tensyuic acid, hexylitaconic acid, chlorogenic acid, nigragillin, TMC-256C1, asnipyrone B, asperenone, fumaric acid and fusarubin, all having reported pharmacological activities. CONCLUSION: The present study demonstrates that secondary metabolites produced by endophytic fungi living in various parts of Elaeocarpus floribundus Blume had potential to relief pain and inflammation. The endophytes were found to contain multiple biomolecules effective in rheumatoid arthritis. These findings provide a rationale for the folklore use of the plant in the management of rheumatoid arthritis.

Functional sustainability of nutrient accumulation by periphytic biofilm under temperature fluctuations.

Temperature can fluctuate widely between different seasons, and this may greatly impact many biological processes. However, little is known about its influence on the functioning of benthic microbial communities. Here we investigated the nutrient accumulation capability of periphytic biofilm under temperature fluctuations (17-35°C). Periphytic biofilm maintained the same nutrient accumulation capacity after experiencing the 'warming-hot-cooling' temperature fluctuation under both lab and outdoor conditions as those without temperature disturbance. In response to temperature increase, both community composition and species richness changed greatly and the increase in biodiversity was identified as being the underlying mechanism boosting the sustainable function in nutrient accumulation, indicating zero net effects of community changes. These findings provide insights into the underlying mechanisms of how benthic microbial communities adapt to temperature fluctuations to maintain nutrient accumulation capacity and elucidate that periphytic biofilm plays important roles in influencing nutrient cycling in aquatic ecosystems under temperature changes such as seasonal fluctuations.

Enhanced Adsorptive Bioremediation of Heavy Metals (Cd2+, Cr6+, Pb2+) by Methane-Oxidizing Epipelon.

Cadmium (Cd), chromium (Cr) and lead (Pb) are heavy metals that have been classified as priority pollutants in aqueous environment while methane-oxidizing bacteria as a biofilter arguably consume up to 90% of the produced methane in the same aqueous environment before it escapes into the atmosphere. However, the underlying kinetics and active methane oxidizers are poorly understood for the hotspot of epipelon that provides a unique micro-ecosystem containing diversified guild of microorganisms including methane oxidizers for potential bioremediation of heavy metals. In the present study, the Pb2+, Cd2+and Cr6+ bioremediation potential of epipelon biofilm was assessed under both high (120,000 ppm) and near-atmospheric (6 ppm) methane concentrations. Epipelon biofilm demonstrated a high methane oxidation activity following microcosm incubation amended with a high concentration of methane, accompanied by the complete removal of 50 mg L-1 Pb2+ and 50 mg L-1 Cd2+ (14 days) and partial (20%) removal of 50 mg L-1 Cr6+ after 20 days. High methane dose stimulated a faster (144 h earlier) heavy metal removal rate compared to near-atmospheric methane concentrations. DNA-based stable isotope probing (DNA-SIP) following 13CH4 microcosm incubation revealed the growth and activity of different phylotypes of methanotrophs during the methane oxidation and heavy metal removal process. High throughput sequencing of 13C-labelled particulate methane monooxygenase gene pmoA and 16S rRNA genes revealed that the prevalent active methane oxidizers were type I affiliated methanotrophs, i.e., Methylobacter. Type II methanotrophs including Methylosinus and Methylocystis were also labeled only under high methane concentrations. These results suggest that epipelon biofilm can serve as an important micro-environment to alleviate both methane emission and the heavy metal contamination in aqueous ecosystems with constant high methane fluxes.

Dual benefits of long-term ecological agricultural engineering: Mitigation of nutrient losses and improvement of soil quality.

Soil erosion of sloped farmland in the Three Gorges Reservoir area (TGRA) has led to the serious loss of nutrients, soil quality degradation and the downstream water quality being threatened. Thus, a series of ecological agricultural engineering measures was established in 2011, as a field experiment using citrus (navel orange) plants to reduce soil erosion, which was monitored from 2011 to 2018. These ecological agricultural engineering measures included three treatments: 1) citrus intercropped with white clover (WC), 2) citrus orchard land mulched with straw (SM) and 3) citrus intercropped with hemerocallis (Hemerocallis flava) contour hedgerows (CH). The conventional citrus orchard management was regarded as control (CK). The results show, that compared with CK, nutrient loss from the experiments were reduced by the following amounts: for nitrogen - WC (35.5%), SM (44.0%) and CH (52.0%); for phosphorus - WC (40.0%), SM (51.7%) and CH (58.3%). Therefore, the ecological agricultural engineering measures effectively mitigate the nutrient loss loads of the navel orange citrus gardens. The citrus intercropped with the hemerocallis hedgerows is the most effective measure for the control of nutrient loss. After 8 years of experiment, the soil quality represented by average soil quality index (SQI) in these three treatments, are significantly higher than that of the CK (and the beginning of the experiment). This is because the application of these measures prevented the loss of: soil organic matter, bulk density and total phosphorus. It is predicted that the soil qualities of these three treatments will remain in the range of soil grade II and I for the next 5 years but the soil quality of CK will decrease to soil quality grade II and III. These results show that ecological agricultural engineering measures are a long-term promising and feasible method to reduce soil erosion and enhance soil quality.

Periphytic biofilm: An innovative approach for biodegradation of microplastics.

Microplastics (MPs) have been gaining the attention of environmental researchers since the 1960s anecdotal reports of plastic entanglement and ingestion by marine creatures. Due to their increasing accretion in aquatic environments, as well as resistance towards degradation, marine litter research has focused on microplastics more recently. In the present study, a relatively new method of biodegradation was implemented for the biodegradation of three structurally different MPs i.e. polypropylene (PP), polyethylene (PE) and polyethylene terephthalate (PET). Periphytic biofilm was used for this purpose in various backgrounds of carbon sources (glucose, peptone, and glucose and peptone). Biodegradation of MPs was estimated in terms of weight loss. It was observed that the addition of glucose enhanced the biodegradation of MPs by periphyton biofilm for all MPs (from 9.52%-18.02%, 5.95%-14.02% and 13.24-19.72% for PP, PE and PET respectively) after 60 days compared to natural biofilm alone. To the contrary, peptone, and glucose and peptone together, were inhibitory. Biodegradation was further confirmed by morphological changes observed using SEM, FTIR spectra and GPC lent further support to the results whereby new peaks appeared along with reduction in old peaks and decrease in peak intensities. MiSeq sequencing shows that Deinococcus-thermus > Proteobacteria > Cyanobacteria are the dominant phyla in natural biofilms, and their relative abundances increase after the addition of glucose. However, the abundances shifted to Deinococcus-thermus > Cyanobacteria > Firmicutes > Bacteroidetes, when the biofilms were treated with either peptone alone, or with glucose and peptone together. Therefore, the change in biodegradation capability might also be due to the change in the microbial community structures after addition of the C-sources. These experiments provide an innovative approach towards effective biodegradation of MPs using a relatively new environment-friendly method.

Functional sustainability of periphytic biofilms in organic matter and Cu2+ removal during prolonged exposure to TiO2 nanoparticles.

Responses of microbial communities to nanotoxicity in aquatic ecosystems are largely unknown, particularly with respect to relationship between community dynamics and functions. Here, periphytic biofilms were selected as a model of species-rich microbial communities to elucidate their responses when exposed to titanium dioxide nanoparticles (TiO2-NPs). Especially, the relationships between the functions (e.g. organic matter and Cu2+ removal) and community dynamics after long-term exposure to TiO2-NPs were assessed systematically. After 5days exposure to TiO2-NPs (5mgL-1), periphytic biofilms showed sustainable functions in pollutant removal and strong plasticity in defensing the toxic disturbance of TiO2-NPs, including photosynthesis and carbon metabolic diversity. The sustainable pollutant removal functions of periphytic biofilms were attributed to their functional redundancy. Specifically, periphytic biofilms altered their composition with cyanobacteria, Sphingobacteriia and Spirochaetes being the newly dominant taxa, and changed the carbon substrate utilization pattern to maintain high photosynthesis and metabolic rates. Moreover, extracellular polymeric substances (EPS) especially proteins were overproduced to bind the NPs and thereby reduce the nanotoxicity. The information obtained in this study may greatly help to understand the interactions between microbial community dynamics and function under NPs exposure conditions and functional redundancy is an important mechanism of periphytic biofilms to maintain sustainable functions.

The 'vitamin E regeneration system' (VERS) and an algorithm to justify antioxidant supplementation in diabetes--a hypothesis.

In studies of vitamin E effectiveness in diabetes, there are still controversies surrounding negative observational and positive experimental results. However, there is no controversy that antioxidant vitamin E is regenerated from its pro-oxidant tocopheroxyl radical by a network of interacting co-antioxidants. The network of interacting co-antioxidants has only been studied individually. The hypothesis we propose is that a vitamin E regeneration system (VERS) model based on the complex interactions of the co-antioxidants provides a rationale for vitamin E supplementation as a therapeutic adjunct in diabetes. Furthermore, the factors considered prior to the use of Vitamin E as a supplement in diabetes research and therapy, the effectiveness of vitamin E supplementation and the limitations have been identified in the literature. There is no single study of vitamin E supplementation or efficacy that has determined vitamin E levels in combination with all of the co-antioxidants that interact to regenerate oxidised vitamin E. Therefore, there is a lack of good evidence for or against vitamin E being unilaterally depleted in the antioxidant network. There is also lack of rationale for choice of co-antioxidant supplementation. In essence, the normal conditions for effective antioxidant activity of vitamin E supplementation have yet to be fully explored. We propose a coherent model of VERS, and recommend that VERS status needs to be assessed, as part of evidence-based clinical practice to determine whether vitamin E should be recommended for the diabetic patient. We also propose an algorithm, based on the antioxidant activity and confounding factors, to guide the formulation of a credible hypothesis for clinical trials in assessing the function of vitamin E and treatment outcomes. The proposed model hinges on pertinent questions that have to be addressed to avoid organising a clinical trial that has been identified as biased.

D-dimer identifies stages in the progression of diabetes mellitus from family history of diabetes to cardiovascular complications.

AIM: The aim of the study was to ascertain whether there is variation in the fibrinolytic/coagulation component of diabetes associated with disease progression to macrovascular complications and whether D-dimer can discriminate such variation. METHODS: A total of 343 participants were selected based on clinical status and divided into 7 groups: control, family history of diabetes, pre-diabetes with/without CVD, diabetes with/without CVD and CVD only. Plasma D-dimer was tested. Statistical analysis was performed on log normalised data by ANOVA, Fisher's LSD post hoc test. After the initial analysis, data were classified and re-analysed by quartiles, interquartile range and 95(th) percentile. RESULTS: An overall significant difference between groups (p<0.002) and a steady rise in D-dimer levels that became increasingly higher than control as the disease progressed from pre-diabetes to cardiovascular complications was observed. A statistically significant difference was observed between control versus diabetes (p<0.0005). Analysis of data by quartiles and percentiles gave qualitatively similar results, but a greater significant difference between control versus pre-diabetes at 3rd quartile and interquartile range (p<0.014). CONCLUSION: We report changes in D-dimer levels that may indicate diabetes disease progression to macrovascular complications. Using D-dimer in conjunction with other biomarkers to identify stages of disease progression, commencing from pre-diabetes and continuing to development of asymptomatic and clinical cardiovascular disease in diabetes mellitus, is worthy of consideration.