Total Inhibition Research Articles

Environmental Risk Assessment of Drugs in Tropical Freshwaters Using Ceriodaphnia silvestrii as Test Organism.

In this study we evaluated the acute (immobility/mortality) and chronic (survival and reproduction) effects of the drugs caffeine, diclofenac sodium salt, ketoprofen, paracetamol and salicylic acid on the cladoceran Ceriodaphnia silvestrii. The environmental risks of these substances for tropical freshwaters were estimated from the risk quotient MEC/PNEC. Sensitivity in acute exposures varied up on the drug as follows: salicylic acid (EC50 = 69.15mg L- 1) < caffeine (EC50 = 45.94mg L- 1) < paracetamol (EC50 = 34.49mg L- 1) < ketoprofen (EC50 = 24.84mg L- 1) < diclofenac sodium salt (EC50 = 14.59mg L- 1). Chronic toxicity data showed negative effects of the drugs on reproduction. Paracetamol and salicylic acid caused reduction in fecundity in concentrations starting from 10mg L- 1 and 35mg L- 1, respectively. Ketoprofen caused total inhibition at 5mg L- 1. MEC/PNEC values were relatively low for all drugs. The risk was estimated as low or insignificant, except for caffeine, whose MEC/PNEC value was greater than 1 (moderate risk).

Flavonoid Concentration and Tyrosinase Inhibition Activity of Ethanol Extract of Piper crocatum (Piper crocatum var. Ruiz &amp; Pav) from Various Regions in Indonesia and Their Correlations

Hyperpigmentation is a condition of darkening of the skin which is generally caused by an increase in melanin production. Melanin is produced in melanocytes by the enzyme tyrosinase. Piper crocatum contains flavonoid compounds that are known from previous research to inhibit tyrosinase. The goals of this study were to determine the tyrosinase inhibitory activity and total flavonoid content of seven accessions, as well as look at the Pearson’s correlation and clustering PCA (principal component analysis). The method used was water content analysis, extraction yield measurement, total flavonoids analysis, and in vitro tyrosinase inhibition. Based on the results, P. crocatum from Kendari had the best yield and total flavonoid content of 24.07% and 5.10 mg QE g-1, while P. crocatum from Bogor had the lowest water content with a value of 6.21% and the best in tyrosinase inhibition of 13.77. The correlation between total flavonoid content and percent inhibition showed a very weak correlation. The results of clustering formed four clusters of seven accessions based on total flavonoids and percent inhibition. The cluster was divided into Malang (506mDPL) and Jayapura (287mDPL), Banda Aceh (0.80mDPL) and Bandung (670mDPL), Samarinda (8mDPL) and Bogor (190-350m DPL), and Kendari (14mDPL). In conclusion, the correlation between total flavonoid levels and percent inhibition is very weak and regional diversity had a significant effect on total flavonoids and total inhibition.

Anti-adhesive activity of some secondary metabolites against Staphylococcus aureus on 3D printing medical materials

Recent improvements in 3D printing technology have increased the usage of 3D printed materials in several areas. An exciting and emerging area of applying these next-generation manufacturing strategies is the development of devices for biomedical applications. The main aim of this work was to investigate the effect of tannic acid, gallic acid, and epicatechin gallate on the physicochemical characteristics of acrylonitrile butadiene–styrene (ABS) and Nylon 3D printing materials using the contact angle method. The adhesion of Staphylococcus aureus on untreated and treated materials was evaluated by scanning electron microscopy (SEM) analysis and the images were treated by MATLAB software. The results of the contact angle measurements showed a significant change in the physicochemical properties of both surfaces, indicated an increase in the electron donor character of 3D printing materials following treatment. Thus, the ABS surfaces treated with tannic acid, gallic acid, and epicatechin gallate have become more electron donating. Furthermore, our results proved the ability of S. aureus to adhere on all materials with a percentage of 77.86% for ABS and 91.62% for nylon. The SEM has shown that all actives molecules were sufficient to obtain better inhibition of bacterial adhesion, which tannic acid has shown a total inhibition of S. aureus on ABS. From these results, our treatment presents a high potential for utilization as an active coating to prevent bacterial attachment and the eventual biofilm development in medical field.

Peels extract of, and and it\'s antioxidant efficacy

The primary supply of minerals, vitamins, carbohydrates, flavonoids, phenolic compounds, and other nutrients in the globe is found in fruits and fruit peels. They are a source of supplementary antioxidants as well. DPPH radical scavenging, Catalase activity, and Total Reducing Power were used to assess the antioxidant potential of Punica granatum, Citrus limetta, and Musa paradisiaca. The best antioxidant activity for DPPH assays is demonstrated by methanol peel extracts of Punica granatum (97.35), Musa paradisiaca (98.1), and Citrus limetta (96.08) at a concentration of 0.1 mM/ml. Citrus limetta and Musa paradisiaca had the highest antioxidant capabilities, with catalase activity of fresh Punica granatum peel measuring 0.13 mg/ml, 0.02 mg/ml, and 0.02 mg/ml, respectively. The greatest total decreasing inhibition. Citrus limetta (98.35%), Musa paradisiaca (97.53%), and Punica granatum peel extract have the highest levels of overall reducing power inhibition. The antioxidant efficiency of each fruit peel extract used in the current study is good.

Inhibition of phospholipase A2 from Naja haje and Naja nigricollis venoms by active fraction of Moringa oleifera leaves: in vitro and in silico methods

Phospholipases are one of the principal toxic enzymes in snake venoms inducing a wide variety of pharmacological effects after envenomation. Natural inhibitors from plants are known to inhibit the toxic enzyme activities of snake venoms. In this study, ethanol crude extract of M. oleifera leaves was partitioned using n-hexane and ethyl acetate after which fractionation was done using column and thin layer chromatography. Subsequently, the inhibitory activities of the crude extract and sub-fractions of M. oleifera were investigated against phospholipases A2 isolated from Naja haje and Naja nigricollis venoms using in vitro and in-silico approaches while EchiTab-PLUS polyvalent antivenom was used as the standard drug. The molecular weight of isolated N. haje phospholipase A2 (NH-PL) and N. nigricollis phospholipase A2 (NN-PL) were 24.11 and 35.22 kDa respectively. NH-PL enzyme had a specific activity of 2.70 μM/min/mg substrate while NN-PL activity was 2.10 μM/min/mg substrate. The Km of NH-PL was 0.330 μM with Vmax of 0.085 μM/mL min while NN-PL had Vmax of 0.198 μM/mL.min and Km of 0.670 μM. M. oleifera n-hexane sub-fraction 5 (MOLH5) exhibited a total inhibition of NN-PL and NH-PL enzyme activities at all concentrations used. Molecular docking of the phytoconstituents of MOLH5 against the catalytic site of phospholipase A2 revealed 2-Hydrazino-8-hydroxy-4-phenylquinoline as the lead compound and a potential drug candidate with a docking score of −6.789 kcal/mol. Findings indicated that MOLH5 possesses phospholipase A2 natural inhibitors that could be explored as a therapy for snake envenoming.

Temporary Occlusion of Common Carotid Arteries Does Not Evoke Total Inhibition in the Activity of Corticospinal Tract Neurons in Experimental Conditions.

Temporary occlusion of the common cervical artery is the reason for ischemic stroke in 25% of patients. Little data is provided on its effects, especially regarding neurophysiological studies verifying the neural efferent transmission within fibers of the corticospinal tract in experimental conditions. Studies were performed on 42 male Wistar rats. In 10 rats, ischemic stroke was evoked by permanent occlusion of the right carotid artery (group A); in 11 rats, by its permanent bilateral occlusion (B); in 10 rats, by unilateral occlusion and releasing after 5 min (C); and in 11 rats, by bilateral occlusion and releasing after 5 min (D). Efferent transmission of the corticospinal tract was verified by motor evoked potential (MEP) recordings from the sciatic nerve after transcranial magnetic stimulation. MEPs amplitude and latency parameters, oral measurements of temperature, and verification of ischemic effects in brain slides stained with hematoxylin and eosin staining (H + E) were analyzed. In all groups of animals, the results showed that five minutes of uni- or bilateral occlusion of the common carotid artery led to alterations in brain blood circulation and evoked changes in MEP amplitude (by 23.2% on average) and latency parameters (by 0.7 ms on average), reflecting the partial inability of tract fibers to transmit neural impulses. These abnormalities were associated with a significant drop in the body temperature by 1.5 °C on average. Ten minutes occlusion in animals from groups A and B resulted in an MEP amplitude decrease by 41.6%, latency increase by 0.9 ms, and temperature decrease by 2.9 °C of the initial value. In animals from groups C and D, five minutes of recovery of arterial blood flow evoked stabilization of the MEP amplitude by 23.4%, latency by 0.5 ms, and temperature by 0.8 °C of the initial value. In histological studies, the results showed that ischemia was most prominent bilaterally in sensory and motor areas, mainly for the forelimb, rather than the hindlimb, innervation of the cortex, putamen and caudate nuclei, globulus pallidus, and areas adjacent to the fornix of the third ventricle. We found that the MEP amplitude parameter is more sensitive than the latency and temperature variability in monitoring the ischemia effects course following common carotid artery infarction, although all parameters are correlated with each other. Temporary five-minute lasting occlusion of common carotid arteries does not evoke total and permanent inhibition in the activity of corticospinal tract neurons in experimental conditions. The symptoms of rat brain infarction are much more optimistic than those described in patients after stroke, and require further comparison with the clinical observations.

Leveraging the tolerogenic potential of TNF-α and regulatory B cells in organ transplantation.

A subset of B-cells with tolerogenic functions, termed B-regulatory cells or Bregs, is characterized by the expression of anti-inflammatory/tolerogenic cytokines, namely IL-10, TGF-β, and IL-35, that contribute to their regulatory functions. Breg regulation favors graft acceptance within a tolerogenic milieu. As organ transplantation invariably triggers inflammation, new insights into the crosstalk between cytokines with dual properties and the inflamed milieu are needed to tailor their function toward tolerance. Using TNF-α as a proxy of dual-function cytokines involved in immune-related diseases and transplantation settings, the current review highlights the multifaceted role of TNF-α. It focuses on therapeutic approaches that have revealed the complexity of TNF-α properties tested in clinical settings where total TNF-α inhibition has proven ineffective and often detrimental to clinical outcomes. To improve the efficacy of current TNF-α inhibiting therapeutics, we propose a three-prong strategy to upregulate the tolerogenic pathway engaging the TNFR2 receptor while simultaneously inhibiting the inflammatory mechanisms associated with TNFR1 engagement. When combined with additional administrations of Bregs-TLR that activate Tregs, this approach may become a potential therapeutic in overcoming transplant rejection and promoting graft tolerance.

Continuous Production of Ethanol, 1-Butanol and 1-Hexanol from CO with a Synthetic Co-Culture of Clostridia Applying a Cascade of Stirred-Tank Bioreactors.

Syngas fermentation with clostridial co-cultures is promising for the conversion of CO to alcohols. A CO sensitivity study with Clostridium kluyveri monocultures in batch operated stirred-tank bioreactors revealed total growth inhibition of C. kluyveri already at 100 mbar CO, but stable biomass concentrations and ongoing chain elongation at 800 mbar CO. On/off-gassing with CO indicated a reversible inhibition of C. kluyveri. A continuous supply of sulfide led to increased autotrophic growth and ethanol formation by Clostridium carboxidivorans even at unfavorable low CO concentrations. Based on these results, a continuously operated cascade of two stirred-tank reactors was established with a synthetic co-culture of both Clostridia. An amount of 100 mbar CO and additional sulfide supply enabled growth and chain elongation in the first bioreactor, whereas 800 mbar CO resulted in an efficient reduction of organic acids and de-novo synthesis of C2-C6 alcohols in the second reactor. High alcohol/acid ratios of 4.5-9.1 (w/w) were achieved in the steady state of the cascade process, and the space-time yields of the alcohols produced were improved by factors of 1.9-5.3 compared to a batch process. Further improvement of continuous production of medium chain alcohols from CO may be possible by applying less CO-sensitive chain-elongating bacteria in co-cultures.

PROCESSING TECHNOLOGY OF BUAS-BUAS LEAVES (PREMNA PUBESCENS BLUME) INTO LIQUID SOAP AND HAND SANITIZER TESTED ORGANOLEPTIC AND ANTI-BACTERIAL

This study aims to produce liquid soap and hand sanitizer seen from organoleptic and antibacterial tests of buas-buas leaves (Premna pubescens Blume). This research was conducted on April 20, 2022 to May 21, 2022 at the Biology Laboratory of Medan State University. This type of research is an experimental study with a completely randomized factorial design. The number of treatments in the antibacterial test was 6 combinations of liquid soap and hand sanitizer formulas with 3 replications each. While in the organoleptic test, the number of liquid soap and hand sanitizer formulations was 4 formulas. Data analysis in the antibacterial test is descriptive quantitative, while the organoleptic test uses Analysis of Variance (ANOVA) followed by the Duncan test. The parameters observed in this study were the inhibition zone of liquid soap and buas-buas hand sanitizer extract against Eschericia and Staphyloccus aureus bacteria. And the level of panelist preference for liquid soap formulas and extracts of buas-buas hand sanitizer. From the results of the study, it was found that the hand sanitizer was able to inhibit the growth of S. aureus bacteria by an average of 15 mm and against E. bacteria by 16 mm. In liquid soap with an average total inhibition zone against S. aureus bacteria is 17 mm and against E. bacteria is 19 mm. From the results of the Anova test analysis, there are differences in the level of preference for hand sanitizer formulations on color organoleptic properties with a significant value in the sample of 0.000 &lt;0.05 and the level of absorption of a significant value in the sample of 0.001 &lt;0.05. Meanwhile, in the liquid soap preparation, there was no difference in the level of preference for the five organoleptic properties of the formulation

Lipopeptide surfactant killing of Ichthyophthirius multifiliis: Mode of action

The lipopeptide SPH6 isolated from the bacterial strain Pseudomonas H6 has surfactant properties and shows a lethal effect on all external stages of the problematic gill parasitic ciliate Ichthyopthirius multifiliis. The mode of action has remained enigmatic, but in the present study we have elucidated the mechanisms. I. multifiliis tomonts were exposed to a range of SPH6 concentrations (from 2.5 to 160 µg/mL), until the total motility inhibition of cells, cytoplasm and cilia. The parasites were subsequently examined by histology, light and scanning electron microscopy and enzyme activity assays (19 enzymes). The surfactant did not interfere with enzyme reactivity at any concentration, but at SPH6 concentrations 40 µg/mL and above the parasite cells became de-ciliated. Perforations were observed in the plasma membrane, and their origin and function may be associated with surfactant damage of the cell membrane or areas for extrusome release. Additional killing mechanisms may be involved, because lower concentrations were lethal as well, although the effect on density of cilia was not as pronounced. The study suggests that one mode of action mechanism is the surfactant attachment to and penetration of the parasite plasma membrane followed by detachment of cilia.

Seasonal Effects on Phenolic Contents and In Vitro Health-Promoting Bioactivities of Sacred Lotus (Nelumbo nucifera)

Sacred lotus (Nelumbo nucifera) is a commercial product in Asian countries. Almost all parts of the lotus plant are consumed as food or used as traditional medicine due to their high contents of secondary metabolites such as phenolics and alkaloids. However, agricultural management of the sacred lotus occurs during the rainy season, and the plant enters a resting stage during the dry season. Thus, seasonal variation (beginning, middle and end of the rainy season) was investigated for total phenolic contents (TPCs), antioxidant capacities and inhibitions of the key enzymes relevant to chronic diseases including Alzheimer's disease (β-secretase, acetylcholinesterase and butyrylcholinesterase), hypertension (angiotensin-converting enzyme), obesity (lipase) and diabetes (α-glucosidase) of different sacred lotus parts (seed embryo, petal, stamen, old leaf, leaf stalk and flower stalk). Results indicated that an aqueous extract of stamen in all harvesting seasons exhibited potentially high TPCs, which led to high antioxidant activities and most enzyme inhibitions (up to 53.7-fold higher) than the others collected in the same harvesting period. The phenolic content and biochemical activities in stamen harvested at the beginning of the rainy season were up to 4-fold higher than during other harvesting periods. This information benefits the agricultural management of sacred lotus and supports consumption of different sacred lotus parts for health promotion. Results can be used as an initial database for future product development from different sacred lotus parts.

Phenolic compounds and antioxidants activity of banana peel extracts: Testing and optimization of enzyme-assisted conditions

Banana processing industry generates a large number of by-products mainly constituted by peel that can be a good source of bioactive polyphenols. Extraction of phenolic compounds using optimum extraction conditions enhances the yield and quality of the desired compounds. Meanwhile, a well-chosen optimization procedure has the ability to reduce the amount of time, solvent, and temperature needed, which will consequently lower the overall process cost. In this study, the optimization of the enzyme-assisted extraction conditions was evaluated for the maximum extraction of phenolic compounds from banana peels using three enzymes viscozyme® L, cellulase, and pectinase. The optimum conditions were achieved using enzyme concentration (0–2%, v/v), extraction time (1–12 hrs), extraction temperature (35–60 °C), and the solute-liquid ratio (1:5–1:30, w/v) at pH 4.0. The responses such as total phenol content (TPC), total flavonoid content (TFC), DPPH and ABTS inhibition activity, and α-glucosidase inhibitory activity were determined by spectrophotometric analysis. Viscozyme® L was found more effective compared to cellulase, and pectinase, and the optimum condition was obtained with 1.0% enzyme concentration, 9 hrs extraction time, 55 °C extraction temperature, and the solute-liquid ratio 1:25. The values of TPC, TFC, DPPH and ABTS, and α-glucosidase inhibitory activity at optimized condition were 25.37 mg GAE/g DM, 13.99 mg QE/g DM, 81.59%, 88.25%, and 74.67% scavenging ability, respectively. Therefore, viscozyme-assisted extraction could be a promising method for phenolic compounds from banana peels and the utilization of banana peels as valuable ingredients for food and pharmaceuticals.

Eco-Friendly and Facile Integrated Intumescent Polyelectrolyte Complex Coating with Universal Flame Retardancy and Smoke Suppression for Cotton and its Blending Fabrics

Cotton and its blended fabrics are widely used textile materials in daily life; however, their high flammability brings serious fire hazards. It remains a huge challenge to endow cotton and its blended fabrics through simple and universal technology. In this work, a novel water-based polyelectrolyte complex (PEC) coating was developed from chitosan and a water treatment agent (amino trimethylphosphonic acid). By controlling the degree of ion pair aggregation through pH adjustment, the intumescent and stable PEC coating can be constructed quickly via facile blading coating and curing processes. High transparency allows for the deposition of the coating with little effect on the original pattern of the coated fabric. Additionally, when the coated fabrics were exposed to flame, the PEC coating underwent a quick self-char-forming reaction in advance and formed a protective char layer covered on the fibers. Thus, the PEC coating with low adding-on (11.5–21.5 wt %) shows universally high flame retardancy for cotton, polyester/cotton blends, and polyester/poly(vinyl alcohol)/cotton blends. The coated fabrics show excellent extinguishing performances, high limiting oxygen index values of 27.5%–28.5%, and total release smoke inhibition of 42%. This work provides a promising universal technology for manufacturing fire-safety cotton and its blends in a simple and eco-friendly way.

Biocontrol potential of wine yeasts against four grape phytopathogenic fungi disclosed by time-course monitoring of inhibitory activities.

Grapes' infection by phytopathogenic fungi may often lead to rot and impair the quality and safety of the final product. Due to the concerns associated with the extensive use of chemicals to control these fungi, including their toxicity for environment and human health, bio-based products are being highly preferred, as eco-friendlier and safer alternatives. Specifically, yeasts have shown to possess antagonistic activity against fungi, being promising for the formulation of new biocontrol products.In this work 397 wine yeasts, isolated from Portuguese wine regions, were studied for their biocontrol potential against common grapes phytopathogenic fungal genera: Aspergillus, Botrytis, Mucor and Penicillium. This set comprised strains affiliated to 32 species distributed among 20 genera. Time-course monitoring of mold growth was performed to assess the inhibitory activity resulting from either diffusible or volatile compounds produced by each yeast strain. All yeasts displayed antagonistic activity against at least one of the mold targets. Mucor was the most affected being strongly inhibited by 68% of the tested strains, followed by Botrytis (20%), Aspergillus (19%) and Penicillium (7%). More notably, the approach used allowed the detection of a wide array of yeast-induced mold response profiles encompassing, besides the decrease of mold growth, the inhibition or delay of spore germination and the complete arrest of mycelial extension, and even its stimulation at different phases. Each factor considered (taxonomic affiliation, mode of action and fungal target) as well as their interactions significantly affected the antagonistic activity of the yeast isolates. The highest inhibitions were mediated by volatile compounds. Total inhibition of Penicillium was achieved by a strain of Metschnikowia pulcherrima, while the best performing yeasts against Mucor, Aspergillus and Botrytis, belong to Lachancea thermotolerans, Hanseniaspora uvarum and Starmerella bacillaris, respectively. Notwithstanding the wide diversity of yeasts tested, only three strains were found to possess a broad spectrum of antagonistic activity, displaying strong or very strong inhibition against the four fungal targets tested. Our results confirm the potential of wine yeasts as biocontrol agents, while highlighting the need for the establishment of fit-for-purpose selection programs depending on the mold target, the timing, and the mode of application.

Antibacterial Activity of Gyrinops versteegii Fruit Extracts against Staphylococcus aureus and Escherichia coli and GC-MS Analysis

Gyrinops versteegii is widely used in the perfume, incense, and cosmetic industries as a raw material. Other potential uses of the plant are being explored, including in food and medicine. Therefore, this study carried out antibacterial assay and gas chromatography-mass spectroscopy of G. versteegii fruit extracts in three solvents with different polarities, i.e., n-hexane, dichloromethane, and methanol. The agar well diffusion method was then used to test the extracts against Staphylococcus aureus and Escherichia coli. The dichloromethane extract showed the most effective antibacterial activity against S. aureus at a concentration of 40%, with a zone of inhibition of 13.17 mm compared to E. coli, for which it was 7 mm. Furthermore, the bacterial species showed different responses to the extracts. Total and partial inhibition was shown by the G. versteegii fruit extracts and E. coli, respectively, against S. aureus. Furthermore, GC-MS identified the following compounds in G. versteegii fruit extract: palmitic, oleic, and stearic acid, as well as bis-(2-ethylhexyl) phthalate, 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one, methyl octadec-9-enoate, squalene, and 2-monopalmitin derivates. The results showed antibacterial potency of G. versteegii fruit extract against pathogenic bacteria. Additionally, the antibacterial activity of the extract was stronger against S. aureus compared to E. coli.

Role of Pel and Psl polysaccharides in the response of Pseudomonas aeruginosa to environmental challenges: oxidative stress agents (UVA, H2O2, sodium hypochlorite) and its competitor Staphylococcus aureus.

Pseudomonas aeruginosa is a versatile bacterium capable of adapting to a wide range of stress factors, including solar UVA radiation (400-315 nm). High UVA doses produce lethal effects due to the action of reactive oxygen species. Sublethal UVA doses also induces oxidative damage, but, in addition, it triggers a variety of adaptive responses, including the overexpression of pelA and pslA genes in P. aeruginosa. These genes encode the synthesis of Pel and Psl, which are essential polysaccharides in biofilm formation. The present study analysed the role of Pel and Psl in the adaptive responses generated by exposure to low UVA doses, and their importance in the response to lethal doses of UVA, hydrogen peroxide (H2O2), and sodium hypochlorite, in both planktonic cells and submerged and air-liquid interface (ALI) biofilms. It also studied the roles of Pel and Psl in P. aeruginosa-Staphylococcus aureus interaction. The results demonstrate that the capacity of sublethal UVA exposure to increase cell hydrophobicity and cell attachment and generate cross-protection phenomena in P. aeruginosa depends on the presence of Pel and Psl. The study also shows that Pel and Psl have a key role in the tolerance to lethal doses of UVA radiation, sodium hypochlorite and H2O2, in both biofilms and planktonic cells. Finally, co-culture assays showed total inhibition of S. aureus growth in presence of P. aeruginosa. This phenomenon depends, at least in part, on the simultaneous presence of Pel and Psl in planktonic cells and biofilms, suggesting a relevant role of these polysaccharides in the interaction between these species.

Effect of sulfur on pollen germination of Clemenules mandarin and Nova tangelo.

This study aims to elucidate whether sulfur can inhibit citrus pollination by affecting pollen grains. For this, four sulfur-based products (inorganic sulfur, water dispersible granular sulfur, ammonium sulfate, copper sulfate) were tested to evaluate their effect on pollen germination and pollen tube growth of two citrus varieties: Clemenules mandarin (Citrus clementina) and Nova tangelo (Citrus clementina x [Citrus paradisi x Citrus reticulata]). Pollen grains were extracted from the flowers of these two varieties and subsequently placed in Petri dishes with modified BK (boron and potassium) germination medium with six concentrations of the sulfur-based products (0.2, 2, 20, 200, 2,000, 20,000 mg l-1). All the dishes were incubated and the pollen germination rate was calculated. All the sulfur products showed progressive pollen germination inhibition with a rising sulfur concentration. CTC50 (50% cytotoxicity inhibition) was around 20 mg l-1, with significant differences among treatments. Total pollen germination inhibition took place at 20,000 mg l-1. These results demonstrate that sulfur application can affect citrus pollination.

Ultrasonic Extraction of Phenolic Compounds from Eggplant Peel and Formulation of Eggplant Peel Extract-Enriched Ice-Cream

In this study, ultrasound-assisted extraction (UAE) was used for the extraction of bioactive compounds from eggplant peels (EPP) and conditions were optimized by using response surface methodology (RSM). Methanol concentrations (60%, 70%, and 80%), time (30 min, 45 min, and 60 min), and temperature (30°C, 45°C, and 60°C) were selected as independent extraction parameters, whereas total anthocyanin content (TAC), DPPH inhibition, and total phenolic content (TPC) were response variables. The optimal extraction was at 45°C for 45 min of extraction time with 70% solvent which corresponded to TAC, TPC, and DPPH inhibition values of 7.94 mg/g, 7.03 mg GAE/g, and 94.8%, respectively. The optimized EPP extract was chemically characterized by a Fourier-transform infrared spectrometer (FTIR), high-performance liquid chromatography (HPLC), and a gas chromatography mass spectrometer (GCMS). The optimized extract was further evaluated for antioxidant and anticancer potential. For antioxidant and anticancer potential, the corresponding IC50 values of the EPP extract were 243.2 μg/ml and 1.52–1.99 mg/ml, respectively. Furthermore, the EPP extract significantly inhibited the migratory ability of cancer cells in a dose-dependent manner. Major components identified in the EPP extract were chlorogenic acid (261.76 mg/kg), benzoic acid (184.41 mg/kg), syringic acid (78.48 mg/kg), p-coumaric acid (49.59 mg/kg), cinnamic acid (32.17 mg/kg), quercetin (5.24 mg/kg), sinapic acid (5.14 mg/kg), and gallic acid (4.34 mg/kg). The EPP extract-enriched ice-cream showed high antioxidant potential and consumer acceptability than the blank ice-cream formulation. The EPP extract, due to its antioxidant and anticancer potential, can be used in the formulation of functional food products.

Medicago sativa L. Plant Response against Possible Eustressors (Fe, Ag, Cu)-TiO2: Evaluation of Physiological Parameters, Total Phenol Content, and Flavonoid Quantification.

The present study analyzed Medicago sativa L. crops irrigated by TiO2 in the anatase phase and TiO2 doped with Ag, Fe, and Cu ions at 0.1%w synthesized using the sol-gel method (SG) and the sol-gel method coupled with microwave (Mw-SG). The materials were added to the irrigation water at different concentrations (50, 100, and 500 ppm). Stress induction by nanomaterials was observed by measuring stem morphology, chlorophyll index, total phenols and flavonoids, and antioxidant activity through the DPPH (2,2-diphenyl-1-picrylhydrazy) radical inhibition assay. The nanomaterial treatments caused statistically significant reductions in parameters such as stem length, leaf size, and chlorophyll index and increases in total phenol content and DPPH inhibition percentage. However, the observed effects did not show clear evidence regarding the type of nanomaterial used, its synthesis methodology, or a concentration-dependent response. By generally grouping the results obtained to the type of dopant used and the synthesis method, the relationship between them was determined employing a two-way ANOVA. It was observed that the dopant factors, synthesis, and interaction were relevant for most treatments. Additionally, the addition of microwaves in the synthesis method resulted in the largest number of treatments with a significant increase in the total content of phenols and the % inhibition compared to the traditional sol-gel synthesis. In contrast, parameters such as stem size and chlorophyll index were affected under different treatments from both synthesis methods.

Insight into the effect of natural organic matter on the photooxidation of arsenite induced by colloidal ferric hydroxides in water

Surface complexation of arsenite (As(III)) on colloidal ferric hydroxide (CFH) plays an important role not only in the adsorptive immobilization of As(III) but also in the subsequent oxidation of As(III) to arsenate (As(V)) through light-induced ligand-to-metal charge transfer (LMCT) in water at near-neutral pH. However, the effects of natural organic matter (NOM), especially humic substances (HSs) and low molecular weight carboxylic acids (CAs), on the photochemistry of the CFH-As(III) system have not been sufficiently understood. In this work, the inhibition of photooxidation of As(III) in terms of the observed apparent rate constant (kobs) by six HSs (below 16 mg L−1) and seven CAs (below 2.5 mM) has been observed in water containing 66 μM Fe(III) and 5 μM As(III) at pH 7 under simulated solar irradiation consisting of UVA (λmax 365 nm) and UVB (λmax 313 nm) lights. Total inhibition factors (T) have been determined from the combined effect of light-screening factor (S) and competitive complexation factor (C), wherein both S and C varied with NOM concentration. S was obtained by determining the absorbance of NOM, and C was obtained by fitting modified Langmuir or Freundlich models to the amount of As(III) desorbed from CFH upon the addition of NOM. Statistical analysis between the experimental Texp and the calculated one according to Tcal = S × C showed that the Freundlich model (RMSE for HS 0.1609 and for CA 0.1771) was better than the Langmuir model and was statistically robust (QLOO2= 0.691 > 0.5). This work provided an estimation method for the effects of NOM on As(III) photooxidation in the presence of CFH as well as a deeper understanding of the transformation of arsenic species in sunlit water.