Samples Of Different Origin Research Articles

UV–vis spectroscopy as a rapid method for evaluation of total phenolic hydroxyl structures in lignin

Abstract Phenolic hydroxyl groups in lignin are crucial for understanding its structure, reactivity, and potential applications. Various methods have been developed for the determining phenolic groups in lignin. This study focuses on the comparison of a simple, cost-effective, and time-efficient UV–vis ionization difference technique with the highly accurate 31P NMR spectroscopy for analyzing lignin samples of different origins and isolation methods. The results were carefully evaluated, and the strengths and limitations of each method were discussed. Two eco-friendly UV–vis approaches were proposed for a rapid and comprehensive evaluation of the total phenolic-OH groups: one using a strong alkaline solution for analyzing common types of technical lignins, and another employing multipoint wavelength calculations, effective for analyzing softwood lignins regardless of the extraction method. Additionally, the research highlighted the importance of selecting appropriate model phenolic compounds to accurately assess the phenolic hydroxyl group content in lignins using the UV–vis method. Offering straightforward and rapid analysis, with results closely aligning with 31P NMR data, this method is a promising alternative for routine analysis.

Portable fiber-optic sensor for simple, fast, cost-effective, and environmentally friendly quantification of total acidity in real-world applications

In this work, an innovative fiber-optic sensor for measuring total acidity (TA: expressed as the % w/v of acetic acid) in beverages was developed. For this purpose, we relied on the kinetic principles of heterogeneous solid-phase reactions (slow reactions due to diffusion processes) to develop a novel pH-sensitive fluorescent membrane calibration method for the quantification of TA. In the proposed calibration method, a linear relationship between TA and the protonation rate of a pH-sensitive fluorescent membrane with a pKa ≥ 9 (Paper-FM) is established. Paper-FM was synthesized by the covalent immobilization of the pH-probe Nile Blue on a porous paper membrane. In addition, a 3D-printed interface was designed to implement Paper-FM into a 0.5 mm diameter optical fiber. The fiber-optic sensor developed in this work was tested by analyzing 21 vinegar samples of different origins, and the results were successfully validated with a reference titration method. The results presented in this work show that our fiber-optic sensor allows a direct, simple, and fast (15 s response time) quantification of TA in vinegar samples. In addition, it is environmentally friendly, because, unlike titration methods, it does not generate toxic waste, is reversible, and is extremely stable (a 0.9 mm diameter circle of Paper-FM allows at least 50 consecutive measurements).

The first ITS1 profiling of honey samples from the Southeast Asian region Lombok, Bali and Banggi Island

Southern Asian flowers offer honeybees a diversity of nectar. Based on its geographical origin, honey quality varies. Traditional methods are less authentic than DNA-based identification. The origin of honey is determined by pollen, polyphenolic, and macro-microorganisms. In this study, amplicon sequencing targets macro-microorganisms in eDNA using the ITS1 region to explore honey’s geographical location and authentication. The variety of honey samples was investigated using ITS1 with Illumina sequencing. For all four honey samples, raw sequence reads showed 979,380 raw ITS1 amplicon reads and 375 ASVs up to the phylum level. The highest total number of 202 ASVs up to phylum level identified Bali honey with 211,189 reads, followed by Banggi honey with 309,207 a total number of 111 ASVs, and Lombok represents only 63 ASVs up to phylum level with several read 458,984. Based on Shannon and Chao1, honey samples from Bali (B2) and (B3) exhibited higher diversity than honey from Lombok (B1) and green honey from Sabah (B4), while the Simpson index showed that Banggi honey (B4) had higher diversity. Honey samples had significant variance in mycobiome taxonomic composition and abundance. Zygosaccharomyces and Aspergillus were the main genera found in Lombok honey, with percentages of 68.81% and 29.76% respectively. Bali honey samples (B2 and B3) were identified as having a significant amount of the genus Aureobasidium, accounting for 40.81% and 25% of the readings, respectively. The microbiome composition of Banggi honey (B4) showed a high presence of Zygosaccharomyces 45.17% and Aureobasidium 35.24%. The ITS1 analysis effectively distinguishes between honey samples of different origins and its potential as a discriminatory tool for honey origin and authentication purposes.

Analysis and removal of bisphenols in recycled plastics using polyethylene glycol

This study examines the presence of bisphenol A (BPA), S (BPS), F (BPF), and M (BPM) in various recycled plastics readily available on the market (LDPE, HDPE, PET, and PP), in light of European Food Safety Authority (EFSA) limits. Twenty samples of different origin are analyzed, cleaning treatments are applied, and the migration potential of these bisphenols into food is studied. BPM is absent in all samples, but a post-consumer recycled LDPE sample reveals high bisphenol concentrations, raising concerns, reaching 8540 ng/g, 370 ng/g, and 29 ng/g of BPA, BPS, and BPF, respectively. Migration tests show substantial migration of these contaminants into food simulants. Using a cleaning treatment with polyethylene glycol (PEG 400) reduces BPA in LDPE, HDPE, PP, and PET samples by 95%, 99%, 97% and 28%, respectively, highlighting the importance of cleaning treatments across various polymers in plastic recycling. These findings not only protect food safety but addressing environmental challenges associated with plastic recycling.

Combination of a magnetic ionic liquid and magnetic particles for the determination of Pb(II) and Sn(IV) using electrothermal atomic absorption spectrometry

A procedure for the determination of traces of lead and tin by electrothermal atomic absorption spectrometry (ETAAS) after complexation with diethyl dithiophosphate and preconcentration by using a microextraction stage with a magnetic ionic liquid (MIL) supported by ferrite particles is presented. After complexation, the analytes are extracted into the ferrite-supported MIL, the solid particles acting as a carrier to facilitate the separation with a magnet. The analytes are released by treating with acetonitrile and the resulting liquid phase is sampled for the ETAAS measurement. The optimal experimental conditions such as pH, appropriate complexing agent, volumes and doses of all reagents used in the procedure are studied to achieve complete separation of both species. Enrichment factors of 195 and 165 and detection limits of 25 and 72 ng L−1 are obtained for Pb and Sn, respectively. The reliability of the procedure is checked by analyzing six certified reference materials and applied to water samples of different origin, the results being in addition confirmed by standard additions (recoveries 97 ± 7% in all cases).

Occurrence, exposure estimation, and dietary risk assessment of biogenic amines in tea samples marketed in Malaysia

Biogenic amines (BAs) are one of the most studied food contaminants due to their widespread distribution in food matrices. However, the occurrence and dietary risks of BAs in tea, particularly in Malaysia, have not been comprehensively investigated. This study evaluates the occurrence of BAs in selected tea samples from Malaysia's market, and the estimation of the dietary exposure to assess the risk of their dietary intake. The targeted BAs (tyramine, histamine, tryptamine, spermine, spermidine, putrescine, and cadaverine) were extracted with 0.1 M HCl using ultrasound, followed by derivatization using dansyl chloride prior to high performance liquid chromatographic separation. The validated method was applied to analyzing BAs in various tea samples of different origins. Results showed that the occurrence of histamine (14.3–69.5 μg g−1) in fully fermented tea, semi-fermented tea, non-fermented tea, post-fermented tea, and tisanes was 8, 0, 63, 17, and 0%, respectively. Spermidine was found in all samples (except 2 tisanes) with concentrations ranging from 17.6 to 105.4 μg g−1. Tyramine was identified as the most prevalent BA (7.2–1271.7 μg g−1), with a detection frequency of 90.2%. Overall, the average total BAs content in fully fermented tea (284.2 μg g−1), semi-fermented tea (677.0 μg g−1), non-fermented tea (783.8 μg g−1), post-fermented tea (204.6 μg g−1), and tisanes (134.2 μg g−1) were below the recommended level of 1000 μg g−1. Dietary exposure was determined by estimated daily intake, whereas risk assessment was evaluated using the hazard quotient (HQ) and hazard index (HI) approaches. Based on the obtained HQ (≤0.017322) and HI (≤0.033437), the dietary exposure to BAs through the consumption of tea in Malaysia does not pose potential health risks to consumers.

Recycled tire rubber materials in the spotlight. Determination of hazardous and lethal substances

One way of recycling end-of-life tires is by shredding them to obtain crumb rubber, a microplastic material (<0.5 mm), used as infill in artificial turf sports fields or as playground flooring. There is emerging concern about the health and environmental consequences that this type of surfaces can cause. This research aims to develop an analytical methodology able to determine 11 compounds of environmental and health concern, including antiozonants such as N-1,3-dimethylbutyl-N′-phenyl-p-phenylenediamine (6PPD) or N, N´-diphenyl-1,4-phenylenediamine (DPPD), and vulcanization and crosslinking agents, such as N-cyclohexylbenzothiazole-2-sulfenamide (CBS), 1,3-di-o-tolylguanidine (DTG) or hexamethoxymethylmelamine (HMMM) from tire rubber. Ultrasound assisted extraction followed by liquid chromatography coupled to tandem mass spectrometry (UAE-LC-MS/MS) is validated demonstrating suitability. The methodology is applied to monitor the target compounds in forty real crumb rubber samples of different origin including, football pitches, outdoor and indoor playgrounds, urban pavements, commercial samples, and tires. Several alternative infill materials, such as sand, cork granulates, thermoplastic elastomers and coconut fibres, are also collected and analysed. All the target analytes are identified and quantified in the crumb rubber samples. The antiozonant 6PPD is present at the highest concentrations up to 0.2 % in new synthetic fields. The tire rubber-derived chemical 6PPD-quinone (2-((4-methylpentan-2-yl)amino)-5-(phenylamino)cyclohexa-2,5-diene-1,4-dione), recently linked to acute mortality in salmons, is found in all types of crumb rubber samples attaining concentrations up to 40 μg g−1 in football pitches. The crosslinking agent HMMM is detected in most of the playing surfaces, at concentrations up to 36 μg g−1. The tested infill alternatives are free of most of the target compounds. To the best of our knowledge, this study is the largest study considering the target compounds in tire rubber particles and the first to focus on these compounds in playgrounds including the analysis of HMMM, 6PPD-quinone and DTG in crumb rubber used as an infill material.

Isolation and characterization of exopolysaccharides from kombucha samples of different origins

Kombucha is prepared by fermenting sugared green or black tea with a symbiotic culture of bacteria and yeast (SCOBY). Some of the bacteria within the SCOBY are known to form exopolysaccharides (EPS) from sucrose. However, it is yet unknown whether water-soluble EPS are formed in kombucha, and if so, which specific EPS are present. Therefore, different kombucha samples were prepared by fermentation of green and black tea with SCOBYs from different manufacturers. Subsequently, the EPS were isolated and characterized by using various chromatographic methods, partial enzymatic hydrolyses and NMR spectroscopy. It was demonstrated that levans with a varying degree of branching at position O1 (4.3–7.9 %) are present, while only trace amounts of glucans were detected. Furthermore, levans isolated from kombucha had a comparably low molecular weight and the content of levan within the kombucha samples varied from 33 to 562 mg levan/L kombucha. Therefore, our study demonstrated that levans are the main EPS type in kombucha and that levan amounts and structures varied when different starter cultures and ingredients were used. Furthermore, we provide a comprehensive data set on the structural variability of levans from kombucha.

Legacy and emerging per- and polyfluoroalkyl substances in tissue and toilet paper from China

Per- and polyfluoroalkyl substances (PFASs) have been found in toilet paper in Europe, the United States, and Africa; however, their presence in Chinese household paper has not been investigated. In this study, 21 legacy and 30 emerging PFASs were analyzed in tissue and toilet paper from China, including 48 samples of different origins and materials. Median concentrations of chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), hexafluoropropylene oxide homologs (HFPOs), and p-perfluorous nonenoxybenzenesulfonate (OBS) were 0.32, 0.19, and 0.10 ng/g dry weight (dw), respectively. The detection frequencies (DFs) of Cl-PFESAs and OBS both were greater than 96%, followed by hexafluoropropylene oxide trimer acid (HFPO-TrA, DF: 85%). Notably, the level of HFPO-TrA in one sample was as high as 540 ng/g dw, indicating a potential environmental risk to humans. In addition, the concentrations of Cl-PFESAs in toilet paper were significantly higher than that in tissue (p < 0.05). However, no significant differences were observed in the concentrations of PFASs in tissue and toilet paper from different materials and origins. This suggests that PFASs, particularly emerging PFASs, are widely detected in tissue and toilet paper products across China, and their presence is a potential source of landfill contamination and human exposure.

A green-footprint approach for parallel multiclass analysis of contaminants in roasted coffee via LC-HRMS

The development and validation of a simple, comprehensive, and environment-friendly procedure to determine pesticide residues, naturally occurring and processing contaminants in roasted coffee is presented. A solid-liquid extraction of pesticides and mycotoxins with ethyl acetate and the concurrent partition of acrylamide to an aqueous phase follows a parallel analytical strategy that requires a single analytical portion to determine contaminants that are typically analyzed by dedicated single residue methods. The partition rules the lipids out of the aqueous extract before an “in-tube” dispersive solid phase microextraction (dSPME) for acrylamide retention. This is followed by the elution with buffer prior to injection. This extract is independently introduced into the system front end followed by the injection of the compounds from the organic phase, yet all spotted in the same run. A novel liquid chromatography high-resolution mass spectrometry (LC-HRMS) method setup enables the quantification of 186 compounds at 10 µg/kg, 226 at 5 µg/kg, and the acrylamide at 200 µg/kg for a total of 414 molecules, with acceptable recoveries (70–120%) and precision (RSD < 20%) making this strategy significantly faster and cost-effective than the dedicated single residue methods. Even though the presence of chlorpyrifos, acrylamide, and ochratoxin A was confirmed on samples of different origins, the findings were below the limit of quantification. During the storage of raw coffee, no proof of masking of OTA was found; however, condensation with glucose was evidenced during thermal processing experiments with sucrose by using stable isotope labeling (SIL). No detected conjugates were found in roasted nor in commercial sugar-added torrefacto samples, an industrial processing usually carried out above the decomposition temperature of the disaccharide.Graphical abstract

Bioactive compounds of Arctostaphylos uva-ursi wild-growing populations from Bulgaria

Arctostaphylos uva-ursi (L.) Sprengel (bearberry), Ericaceae is a valuable medicinal plant with diuretic and uroantiseptic action which is mainly due to arbutin. In Bulgaria the species is considered as rare. Content assessment of bioactive compounds of A. uva-ursi leaves from three natural populations from Bulgaria was the aim of the present study. Leaf samples were collected from Pirin, Vitosha, and Rhodope Mountains. Bioactive compounds in the methanolic extracts of the samples were analysed by GC/MS. Total phenolic content was determined using Folin–Ciocalteu reagent. Arbutin, quinic acid and gallic acid were detected in the highest amounts. Catechine, 4-hydroxybenzoic acid, chlorogenic acid, triterpenes (α- and β-amyrin, uvaol and lupeol) and other primary and secondary metabolites were found, also. Differences in the content of individual compounds between samples of different origin were established. The highest total phenolic (182.98 mg GAE g-1) and arbutin (8.4%) content was found in the sample from Vitosha Mountain. The presented data characterizes the profile of bioactive compounds in the Bulgarian bearberry raw material for the first time.

Reliability of hypo-osmotic swelling test on fresh and frozen-thawed ejaculated or testicular immotile sperm: A sibling oocyte study

The viability of sperm is a crucial factor for achieving a successful pregnancy in intracytoplasmic sperm injection (ICSI) cycles. The aim of this study was to evaluate the accuracy of the hypo-osmotic swelling test (HOST) in fresh and frozen-thawed sperm samples of different origins (ejaculated/testicular). A retrospective analysis was conducted on the outcomes of 2167 oocytes subjected to ICSI using motile and immotile-HOST-positive sperm from 2011 to 2023. We evaluated embryonic development, as well as clinical, obstetric, and neonatal outcomes in four groups based on different sperm origins (ejaculated/testicular) and processing (fresh/frozen). When comparing the results of ICSI between motile and immotile-HOST-positive sperm within each group, it was observed that there were no significant differences in the outcomes for fresh samples. However, for frozen-thawed samples, fertilization rates and blastocyst development rates were significantly lower when ICSI was performed with immotile-HOST-positive sperm compared to motile sperm. Of note, clinical, obstetric, and neonatal outcomes were statistically similar across all groups. Our findings indicate that HOST is more reliable in fresh samples than in those subjected to the freeze–thaw process. Nonetheless, HOST is considered a safe method for selecting viable sperm in all subgroups.

Contamination of Honeybee (Apis mellifera L.) Royal Jelly by Pesticides and Sample Preparation Methods for Its Determination: A Critical Appraisal.

Pesticides can easily enter the food chain, harming bee populations and ecosystems. Exposure of beehive products to various contaminants has been identified as one of the factors contributing to the decline in bee populations, and multiple food alerts have been reported. Despite this fact, royal jelly, a valuable bee product with nutritional and functional properties, has received less attention in this context. Pesticide residues of different chemical class can contaminate royal jelly when foraging bees collect pollen or nectar from pesticide-treated flowers, or in some cases, due to its frequent and inappropriate use in the treatment of mites in beehives. To monitor this issue and also make it more reliable, it is crucial to develop effective sample preparation methods for extracting pesticides from royal jelly for subsequent analysis. In this context, this review provides information about sample preparation methods (solid-phase extraction, solvent extraction, and QuEChERS-quick, easy, cheap, effective, rugged and safe) and analytical methods that have been validated or improved to extract and analyze pesticides, respectively, in royal jelly samples of different origins. Finally, future perspectives are discussed. With this background, we aim to provide data that can guide future research related to this topic.

Quick insights into whisky — investigating rapid and efficient methods for sensory evaluation and chemical analysis

The evaluation of aroma properties of beverages, both analytically as well as with human sensory studies, is a challenging task and most often related to time- and cost-intensive analyses. Whisky is a spirit offering a wide variety of aroma impressions caused by a complex mixture of aroma active compounds. In the present study, methods for the efficient evaluation of aroma characteristics are evaluated for 16 whisky samples of different origins (Scotch and American). Rate all that apply (RATA) was applied as a rapid method for the sensory evaluation of whiskies. Sensory evaluation of the samples led to the determination of eight significant aroma attributes: caramel-/cream caramel-/toffee-like, vanilla-like, (canned) peach-like, phenolic, smoky, fruity, flowery and (fermented) apple-/cider-like. Chemical analysis was conducted by stir bar sorptive extraction (SBSE) coupled to gas chromatography-mass spectrometry in combination with an in-house data processing tool for semi-automated analyte detection. Through chemical analysis of the whisky samples and automated compound detection, we report over 200 mostly aroma-active volatiles. To test both approaches for their potential for sample classification, a simple classification problem (Scotch vs. American) was applied. Linear discriminant analysis (LDA) indicates both that sensory evaluation by RATA (97.86%) and the applied analytical procedure (96.94%) are suitable for the distinction between the two whisky types. In both approaches, potential markers were determined for the classification. These investigations build a solid foundation for the implementation of a versatile platform facilitating rapid and efficient aroma evaluation in various foodstuffs and beverages.

Studying Efferocytosis Dynamics in Tissue-Resident Macrophages Ex Vivo.

In vitro cocultures of macrophages and apoptotic cells (ACs) provide a practical and useful tool to study efferocytosis. Here, we describe a method for automated quantification and imaging of recognition and engulfment of apoptotic cells by primary macrophages using imaging flow cytometry (IFC). IFC-based analysis allows us to successfully quantify efferocytosis, clearly distinguishing phagocytic from nonphagocytic macrophages and, more importantly, from those in recognition stage, which is not achievable by standard flow cytometrical analysis. To this end, we established a universally employable analysis pipeline to address efferocytosis that can be easily adapted to any macrophage population from samples of different origins.

Microstructural and strength variations in natural sands exposed to diverse environmental conditions

Climatic variation affects the physicochemical properties of geomaterials and its impact on the mechanical performance of infrastructure depends on the nature and origin of the material. The long-term behavior of sand, like any other construction material, can only be fully understood by evaluating its engineering properties under extreme climatic conditions such as repeated cycles of freezing-thawing (FT), wetting-drying (WD), and heating-cooling (HC). In this study, sand samples of different origin, including beach sand and dune sand (relatively aged sands), and quarry dust (relatively young grains) were subjected to 20 independent cycles of FT, WD, and HC. Scanning electron microscopy, x-ray diffraction, and x-ray fluorescence tests were performed for microstructural, surface texture, and chemical composition of the sand samples. Moreover, direct shear test results present the engineering properties such as peak shear strength, strain at failure, and friction angle of each sand sample at the end of various cycles. It is concluded that the findings of this study may provide an improved understanding of how natural sands of different origins respond to various environmental exposure conditions.

Cocoa quality: Chemical relationship of cocoa beans and liquors in origin identitation

In this study, HS-SPME-GC–MS was applied in combination with machine learning tools to the identitation of a set of cocoa samples of different origins. Untargeted fingerprinting and profiling approaches were tested for their informative, discriminative and classification ability provided by the volatilome of the raw beans and liquors inbound at the factory in search of robust tools exploitable for long-time studies. The ability to distinguish the country of origin on both beans and liquors is not so obvious due to processing steps accompanying the transformation of the beans, but this capacity is of particular interest to the chocolate industry as both beans and liquors can enter indifferently into the processing of chocolate. Both fingerprinting (untargeted) and profiling (targeted) strategies enable to decipher of the information contained in the complex dataset and the cross-validation of the results, affording to discriminate between the origins with effective classification models.

Differences in Volatile Organic Compounds in Rhizoma gastrodiae (Tian Ma) of Different Origins Determined by HS-GC-IMS

Headspace gas chromatography–ion mobility spectrometry (HS-GC-IMS) and principal component analysis (PCA) were used to compare the differences in volatile organic compounds (VOCs) of Rhizoma gastrodiae (Tian Ma) from six different origins in Yunnan, Sichuan, Shaanxi, Anhui, Hubei, and Guizhou. A total of 161 signal peaks were identified, and 84 compounds were characterized, including 23 aldehydes, 19 alcohols, 12 ketones, 8 heterocyclic compounds, 7 esters, 4 phenols, 4 acids, 4 ethers, 2 amines, and 1 alkane. The results of cluster analysis and fingerprint similarity analysis based on principal component analysis and Euclidean distance indicated that there were significant differences between the volatile components of Rhizoma gastrodiae from different origins. This study demonstrated that HS-GC-IMS is simple, rapid, accurate, and has a small sample size and can achieve rapid analysis of the differences in volatile compounds between samples of different origins of Rhizoma gastrodiae.

Improving of an easy, effective and low-cost method for isolation of microplastic fibers collected in drying machines filters

Microplastic fibers have been found to be a dominant form of microplastics in water matrixes, and textile industry and domestic washing of synthetic textiles as one of its main sources. Additionally, there is a lack of knowlidge about microplastic fiber release during mechanically drying clothes and textiles due to differences in the isolation of microplastic fiber methods. Limited information available in the literature in terms of the isolation of microplastic fibers from organic-rich samples after using different household equipment represents one of the main challenges leading us to our main goal, to optimise an effective, simple, and low-cost method for the isolation of microplastic fibers from textile fibers of different origins without damaging their structure. This is achieved by primarily removing mineral matter by using density separation with a saturated solution of ZnCl2 followed by removal of organic matter by using hydrogen peroxide (H2O2) and FeCl3 as a catalyst. Identification of microplastic fibers was obtained by optical microscope, Fourier-transform infrared spectroscopy and Thermogravimetric analysis. Clear microscope (both optical and SEM) images, high percentage of obtained FTIR spectra overlap with Polymer Sample laboratory, clear TGA of isolated samples confirmed that this method can be used as a simple and effective method for isolation of microplastic fibers from organic components rich samples of different origin.

Massive Proteogenomic Reanalysis of Publicly Available Proteomic Datasets of Human Tissues in Search for Protein Recoding via Adenosine-to-Inosine RNA Editing.

The proteogenomic search pipeline developed in this work has been applied for reanalysis of 40 publicly available shotgun proteomic datasets from various human tissues comprising more than 8000 individual LC-MS/MS runs, of which 5442 .raw data files were processed in total. This reanalysis was focused on searching for ADAR-mediated RNA editing events, their clustering across samples of different origins, and classification. In total, 33 recoded protein sites were identified in 21 datasets. Of those, 18 sites were detected in at least two datasets, representing the core human protein editome. In agreement with prior artworks, neural and cancer tissues were found to be enriched with recoded proteins. Quantitative analysis indicated that recoding the rate of specific sites did not directly depend on the levels of ADAR enzymes or targeted proteins themselves, rather it was governed by differential and yet undescribed regulation of interaction of enzymes with mRNA. Nine recoding sites conservative between humans and rodents were validated by targeted proteomics using stable isotope standards in the murine brain cortex and cerebellum, and an additional one was validated in human cerebrospinal fluid. In addition to previous data of the same type from cancer proteomes, we provide a comprehensive catalog of recoding events caused by ADAR RNA editing in the human proteome.