Bell Pepper Samples Research Articles

Non-Destructive Monitoring of Sweet Pepper Samples After Selected Periods of Lacto-Fermentation

Fermented food is characterized by positive health-promoting properties. The objective of this study was to distinguish and assess the changes in the flesh structure of sweet bell pepper samples after specific periods of fermentation in a non-destructive manner. Two cultivars of pepper, red and yellow, were subjected to lacto-fermentation. The experiments lasted 56 days and the samples were taken for analysis at the beginning of the study (0 days) and after 3, 7, 10, 14, 21, 28, and 56 days. The fermentation process was monitored based on image features, which were used to develop machine learning models distinguishing samples before and after various periods of lacto-fermentation (0, 3, 7, 10, 14, 21, 28, and 56 days). The average accuracy of the classification of red bell pepper samples was up to 93% for the model built using IBk (Lazy group). The yellow bell pepper samples were distinguished up to 90% accuracy by the LMT algorithm (Trees group). The performed study allowed us to determine the changes in pepper flesh in terms of image textures during lacto-fermentation.

Residue estimation and dietary risk assessment of fenvalerate, novaluron, and profenofos in bell pepper grown under protected and open field conditions.

Residue studies were conducted in bell pepper crops (green and yellow bell pepper) to ensure the safe use of fenvalerate, profenofos, and novaluron (under open field and protected conditions) in randomized block design (RBD) following three applications at a 10-day interval over two consecutive years, 2021 and 2022. A robust analytical method was developed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and gas chromatography-tandem mass spectrometry (GC-MS/MS) for the determination of pesticide residues in bell pepper samples. The half-lives for fenvalerate were 2.47-2.87 and 2.50-3.03days on bell pepper under open field conditions, whereas the corresponding values for bell pepper under protected conditions were 3.84-4.58 and 4.17-4.71days, during 2021 and 2022, respectively. Profenofos displayed half-lives of 2.03-2.65 and 2.15-2.77days in open field conditions and 3.05-3.89 and 3.16-3.78days in protected conditions during 2021 and 2022, respectively. Similarly, novaluron had half-lives of 2.87-3.49 and 3.24-3.75days under protected conditions in 2021 and 2022, respectively. The maximum residue limits (MRLs) were calculated to be 0.6mg/kg for fenvalerate, while for profenofos it was 0.7mg/kg on bell pepper under open field conditions at double doses, at the proposed pre-harvest interval (PHI) of 3days. Likewise, for bell peppers grown under protected conditions, MRLs at the PHI of 3days were determined to be 0.8mg/kg for fenvalerate, 0.3mg/kg for novaluron, and 1.5mg/kg for profenofos. A dietary risk assessment study indicated that the percentage of acute hazard index (% aHI) was significantly lower than 100, and hazard quotient (HQ) values were below 1, signifying no acute or chronic risk to consumers. These findings underscore the safety of consuming bell peppers treated with fenvalerate, profenofos, and novaluron under the protected and open field conditions.

The Influence of Lactic Acid Fermentation on Selected Properties of Pickled Red, Yellow, and Green Bell Peppers

Red, yellow, and green peppers are vegetables rich in natural pigments. However, they belong to seasonal vegetables and need to be treated to prolong their shelf life. One new approach to processing vegetables is to pickle them using lactic acid bacteria. The use of such a process creates a new product with high health value, thanks to the active ingredients and lactic acid bacteria. Therefore, this study aimed to evaluate the effect of the applied strain of lactic acid bacteria (LAB) on the chemical properties, including the content of active compounds (pigments) and the physical properties of the peppers. Levilactobacillus brevis, Limosilactobacillus fermentum, and Lactoplantibacillus plantarum were used for fermentation and spontaneous fermentation. The pigments, polyphenols content, and antioxidant properties were determined in the pickled peppers, as well as sugar content, color, dry matter, texture properties, and the count of lactic acid bacteria. In all samples, similar growth of LAB was observed. Significant degradation of chlorophylls into pheophytins was observed after the fermentation process. No significant differences were observed in the parameters tested, depending on the addition of dedicated LAB strains. After the fermentation process, the vitamin C and total polyphenols content is what influenced the antioxidant activity of the samples. It can be stated that the fermentation process changed the red bell pepper samples in the smallest way and the green ones in the highest way.

The Changes in Bell Pepper Flesh as a Result of Lacto-Fermentation Evaluated Using Image Features and Machine Learning.

Food processing allows for maintaining the quality of perishable products and extending their shelf life. Nondestructive procedures combining image analysis and machine learning can be used to control the quality of processed foods. This study was aimed at developing an innovative approach to distinguishing fresh and lacto-fermented red bell pepper samples involving selected image textures and machine learning algorithms. Before processing, the pieces of fresh pepper and samples subjected to spontaneous lacto-fermentation were imaged using a digital camera. The texture parameters were extracted from images converted to different color channels L, a, b, R, G, B, X, Y, and Z. The textures after selection were used to build models for the classification of fresh and lacto-fermented samples using algorithms from the groups of Lazy, Functions, Trees, Bayes, Meta, and Rules. The highest average accuracy of classification reached 99% for the models developed based on sets of selected textures for color space Lab using the IBk (instance-based K-nearest learner) algorithm from the group of Lazy, color space RGB using SMO (sequential minimal optimization) from Functions, and color space XYZ and color channel X using IBk (Lazy) and SMO (Functions). The results confirmed the differences in image features of fresh and lacto-fermented red bell pepper and revealed the effectiveness of models built based on textures using machine learning algorithms for the evaluation of the changes in the pepper flesh structure caused by processing.

Synthesis of α-Fe2O3/ethyl cellulose-based nanocomposites to extend the shelf-life of Capsicum annuum L. var. grossum

Nanobiotechnology has great potential to improve the shelf-life of eatables with essential nutrient quality. Synthesized nanocomposites were applied to prolong the shelf life of Bell Pepper (Capsicum annuum L. var. grossum). α-Fe2O3 nanoparticles were synthesized using the hydrothermal method and characterized with FTIR and XRD techniques. XRD confirms the crystalline nature of α-Fe2O3 nanoparticles. α-Fe2O3 nanoparticles exhibit remarkable anti-pathogenic properties against Staphylococcus aureus. α-Fe2O3/ethyl cellulose nanocomposite dip-coated bell pepper samples with three different concentrations; FA (1 mg/ml), FB (0.75 mg/ml), FC (0.5 mg/ml) and FU (uncoated control) were studied up to 14 days at room temperature (27 ± 2 °C). Results suggested that nanocomposites enhanced the shelf life of the coated Bell Pepper by preventing microbial and fungal proliferation.Moreover, the nanocomposites did not affect any quality aspects of the Bell Pepper, such as pH, chlorophyll content, moisture content, ascorbic acid, and weight loss. This present study demonstrates that synthesized nanocomposite antimicrobial films can maintain the quality of vegetables and retards microbial and fungal growth in Bell Pepper.

Aptamer-based sensor for specific recognition of malathion in fruits and vegetables by surface-enhanced Raman spectroscopy and electrochemistry combination

ABSTRACT: Aptamers are single-stranded DNA or RNA that can specifically bind to a target substance with high affinity. Pesticides have obvious biological effects and are very harmful to the human body and the environment. Surface-enhanced Raman spectroscopy (SERS) can be combined with aptamer for the rapid detection of pesticide residues because of its simple operation and high sensitivity. However, a single analysis method has certain limitations and can't satisfy the research of complex system. In this study, SERS and electrochemical were used to prove the specific recognition of malathion by aptamer. The biochemical sensor directly detected the SERS spectra of the aptamer, malathion, and aptamer-malathion through the SERS method. Malathion could also be verified the specific recognition of aptamer by differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Based on the peak difference before and after the combination of malathion and aptamer, a detection method for the specific recognition of malathion in a complex system was established. The identification mechanism was discussed. Then, the practical detection of malathion demonstrated the practicability of the method. The method was applied for the detection of malathion in spiked apple and bell pepper samples. The recoveries were in the range of 89.80%–106.50%, and the relative standard deviations were from 2.51%–6.92%. The use of aptamers for the specific detection of pesticides will have the potential for broad applications in the future.

Quality assessment of dried organic bell peppers through composition and sensory analysis

A comprehensive quality evaluation was performed on dried sweet bell pepper samples obtained from two years of production, two genotypes and two drying technologies, using one conventional and two organic cropping systems. A total number of 35 quality indexes, comprising non-volatile and volatile flavor compounds and health related compounds were evaluated for their possible role in the flavor of dried bell pepper: the most significant variations in the data analysis due to the year, drying technique, genotype and cropping system resulted in 25, 25, 16 and 10 significant interactions, respectively. The PCA analysis confirmed the main role of drying technique and sampling year. The malic acid for non-volatile compounds, linalool and 2-methoxy-3-isobutylpyrazine for volatiles represent the most relevant chemical indexes significantly correlating with many sensory descriptors scored by panellists, and are, therefore, proposed as quality markers to be carefully monitored for a correct quality evaluation of dried bell pepper.

Sequential Data Fusion Techniques for the Authentication of the P.G.I. Senise (“Crusco”) Bell Pepper

Bell pepper is the common name of the berry obtained from some varieties of the Capsicum annuum species. This agro-food is appreciated all over the world and represents one of the key ingredients of several traditional dishes. It is used as a fresh product, or dried and ground as a seasoning (e.g., paprika). Specific varieties of sweet pepper present organoleptic peculiarities and they have been awarded by quality marks as a further confirmation of their unicity (e.g., Piment d’Espelette, Pimiento de Herbón, Peperone di Senise). Due to the market value of this aliment, it can be subjected to frauds, such as adulterations and sophistication. The present study lays on these considerations and aims at developing a spectroscopy-based approach for authenticating Senise bell pepper and for detecting its adulteration with common paprika. In order to achieve this goal, 60 pure samples of bell pepper from Senise were analyzed by mid- and near-infrared spectroscopies. Then, in order to mimic the adulteration, 40 mixtures of Senise bell pepper and paprika were prepared and analyzed (by the same spectroscopic techniques). Eventually, two different multi-block classification approaches (sequential and orthogonalized partial least squares linear discriminant analysis and sequential and orthogonalized covariance selection linear discriminant analysis) were used to discriminate between pure and adulterated Senise bell pepper samples. Both proposed procedures achieved extremely successful results in external validation, correctly classifying all the (thirty-five) test samples, indicating that both approaches represent a winning solution for the investigated classification problem.

Gamma radiation treatment to ensure microbial safety of ready to bake (RTB) vegetable toppings/ fillers and retain their nutritional qualities during cold storage

Limited shelf life due to processing associated microbial contamination is one of the major challenging issues with minimally processed ‘Ready to Bake’ (RTB) vegetable products leading to huge post-processing losses. In the current study, three minimally processed vegetables, i.e. tomato, bell pepper and white onion, which are widely used in fast food industries (FFI), such as pizza and burger as well as in households; were studied for their post-processing microbiological profile; and to assess the effect of gamma radiation treatment (0.5–5 kGy) to maintain hygiene during extended storage at low temperature. Prior to radiation treatment, the minimally processed vegetables were packed in low density polyethylene bags (thickness: 50 μm) which is suitable for such agri-produce and compatible to gamma radiation treatment (USA, FDA). Besides, vacuum packaging in multilayered LDPE bags was optimized for shredded onion. Except tomato, which did not contain any detectable presumptive coliform or yeast and mold on day 0, the other two cut vegetables were found to have higher load of microbes, i.e., more than 4.0 log CFUg−1 of total aerobic plate count, 3.0 log CFUg−1of each of yeast and mold counts (YMC) and presumptive coliform (PC) counts. In the radiation treated (2 kGy) vegetables, no PC was detected; even after 20 days of storage; whereas, in the untreated bell pepper, tomato and onion samples PC counts were found to be 4.3 ± 0.1, 3.7 ± 0.2 and 1.7 ± 0.3 log CFUg−1 respectively on day 20 of storage. The data indicated that, the total aerobic plate counts in the 2 kGy irradiated samples were below the permissible limit as per the Food Safety and Standards Authority of India (FSSAI) guidelines. Organoleptic attributes (‘colour’, ‘texture’, ‘flavour’, ‘taste’ and ‘overall acceptability’) of the radiation treated products were found to be well retained even on 20 days of storage. The nutritional adequacy of these products in terms of total energy, fat, protein, carbohydrate, minerals and vitamin content was found to be well retained till the end of the 20 days' storage period. Findings of the study thus establish the efficacy of gamma radiation treatment in ensuring the safety and quality of minimally processed vegetables for their use in FFI as well as domestic kitchens.

Critical points affecting the microbiological safety of bell peppers washed with peroxyacetic acid in a commercial packinghouse

The washing stage from a bell pepper commercial packinghouse was assessed to study some of the critical control points related to bacterial cross-contamination. The washing line comprised two overhead spray bars applications: a pre-wash step without peroxyacetic acid (PAA), and a wash step with PAA. The physicochemical characteristics of the wash water and the bacterial quality and safety of the wash water and bell peppers (including aerobic mesophilic bacteria (AMB), Salmonella spp., and Shiga-toxigenic E. coli (STEC)) were studied. Additionally, the performance of commercial test methods (reflectometry, amperometric probe, chronoamperometric sensor) for measuring the residual concentration of PAA was examined. The bacterial load of the pre-wash water (8.7 ± 1.3 log cfu/100 mL AMB) was very high and thus peppers after the pre-wash showed a significantly higher bacterial load (4.9 ± 0.9 log cfu/g AMB) than the unwashed (3.8 ± 0.7 log cfu/g AMB) or the washed peppers (3.3 ± 0.8 log cfu/g AMB) (p < 0.05). However, no pathogenic bacteria were detected in bell pepper samples (n = 40), and only one water sample was confirmed positive for STEC (n = 64, 1.6% prevalence). The chronoamperometric sensor (PAASense) and the online amperometric probe showed similar results, while the reflectometry (Quantofix) significantly sub estimated (p < 0.05) PAA concentration. The results obtained highlight the need for interventions to improve hygiene in the washing line to ensure the microbiological quality and safety of bell peppers. The maintenance of optimal PAA concentrations in all the washing steps is critical for reducing the chance of water-mediated cross-contamination.

8 THE HERITABILITY OF FEAR CONDITIONING AS A MODEL FOR ANXIETY DISORDER AND TREATMENT RESPONSE

Limited shelf life due to processing associated microbial contamination is one of the major challenging issues with minimally processed ‘Ready to Bake’ (RTB) vegetable products leading to huge post-processing losses. In the current study, three minimally processed vegetables, i.e. tomato, bell pepper and white onion, which are widely used in fast food industries (FFI), such as pizza and burger as well as in households; were studied for their post-processing microbiological profile; and to assess the effect of gamma radiation treatment (0.5–5 kGy) to maintain hygiene during extended storage at low temperature. Prior to radiation treatment, the minimally processed vegetables were packed in low density polyethylene bags (thickness: 50 μm) which is suitable for such agri-produce and compatible to gamma radiation treatment (USA, FDA). Besides, vacuum packaging in multilayered LDPE bags was optimized for shredded onion. Except tomato, which did not contain any detectable presumptive coliform or yeast and mold on day 0, the other two cut vegetables were found to have higher load of microbes, i.e., more than 4.0 log CFUg−1 of total aerobic plate count, 3.0 log CFUg−1of each of yeast and mold counts (YMC) and presumptive coliform (PC) counts. In the radiation treated (2 kGy) vegetables, no PC was detected; even after 20 days of storage; whereas, in the untreated bell pepper, tomato and onion samples PC counts were found to be 4.3 ± 0.1, 3.7 ± 0.2 and 1.7 ± 0.3 log CFUg−1 respectively on day 20 of storage. The data indicated that, the total aerobic plate counts in the 2 kGy irradiated samples were below the permissible limit as per the Food Safety and Standards Authority of India (FSSAI) guidelines. Organoleptic attributes (‘colour’, ‘texture’, ‘flavour’, ‘taste’ and ‘overall acceptability’) of the radiation treated products were found to be well retained even on 20 days of storage. The nutritional adequacy of these products in terms of total energy, fat, protein, carbohydrate, minerals and vitamin content was found to be well retained till the end of the 20 days' storage period. Findings of the study thus establish the efficacy of gamma radiation treatment in ensuring the safety and quality of minimally processed vegetables for their use in FFI as well as domestic kitchens.

Matrix effect evaluation and method validation of organophosphorus pesticide residues in bell peppers (Capsicum annuum L.) by GC–MS determination

ABSTRACT The matrix effects in bell pepper samples were studied. The simultaneous determination of six organophosphorus (OPPs) pesticides (chlorpyrifos, dichlorvos, disulfoton, ethoprophos, fenchlorphos, and prothiofos), by gas chromatography-mass spectrometry (GC/MS) method using sample preparation on QuEChERS-citrate, was developed and validated. Non-organic and organic bell peppers (Capsicum annuum L.) samples were analysed. Matrix-matched calibrations were established to correct matrix effect (ME) for quantification analysis of the six pesticides. All of the pesticides showed matrix-induced signal suppression, where chlorpyrifos and prothiofos were the pesticides that presented the most significant values, −65.54 and −65.31, respectively. The pesticides studied showed good linearity with correlation coefficient values higher than 0.99. The LODs ranged from 0.002 to 0.039 mg kg-1 and LOQs 0.006 to 0.130 mg kg-1. Only one sample of the bell pepper showed contamination with chlorpyrifos (0.177 mg.kg-1), corresponding to a value 17.7 times higher than the MRLs allowed for this crop by European Committee (EC) (0.010 mg.kg-1).

Using Machine Learning and Multi-Element Analysis to Evaluate the Authenticity of Organic and Conventional Vegetables

Concern for the consumption of organic vegetables is growing throughout the world. We verified the efficiency of machine learning techniques in the classification of vegetables produced under both organic and conventional systems in the state of Pernambuco, Brazil. The contents of 25 elements (Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, S, Se, Si, Ti, V, Zn) were determined in 364 vegetable samples. Principal component analysis (PCA) was displayed to get a primary distribution overview of samples. Data mining techniques such as linear discriminant analysis (LDA) were carried out to develop discrimination models based on organic vegetable samples, and feature selection (F-score and chi-squared) combined with classification algorithms (support vector machine—SVM, multilayer perceptron—MLP, and random forest—RF) was applied to these samples. LDA reached 100% in the discrimination models in tomato samples and bell pepper samples, while SVM, combined with chi-squared, outperformed the other algorithms obtaining accuracy of 100% in bell pepper samples (Capsicum annuum) and onion (Allium cepa Hysam) and 97% in tomato (Solanum Lycopersicum) samples, of which 95% was the hit rate in organic samples. For lettuce (Lactuca sativa) samples, the accuracy obtained was 92%, with a 90% hit rate of samples grown in organic systems. This high success rate highlights the potential of using elemental quantification and algorithms as support techniques in the process of authenticity and inspection of organic products.

Residue levels and health risk of pesticide residues in bell pepper in Shandong

ABSTRACTThe purpose of this study was to investigate pesticide residues in bell peppers from Shandong Province, China. A total of 299 samples were collected from 17 cities in 2016. The concentrations of 26 pesticide residues were determined by gas chromatography with mass spectrometry (GC–MS). The results showed that there were 25 pesticides (15 OPs, 7 PYs, 3 CBs) found in 86 bell pepper samples, and the total number of positives was 120. The total frequency was 28.76%. The detection frequency for OPs, PYs and CBs was 16.39%, 12.37% and 3.01%, respectively. The most frequently detected pesticide was bifenthrin, with the frequency of 5.02%. 5.35% of samples contained pesticide residues above the maximum residue limits (MRLs) set by China. 7.36% of samples contained more than one pesticide. The values of %ADI were below 100, while the %ARfD of carbofuran and methidathion exceeded 100 for children. The cumulative risk was highest for OPs. From the public health point of view, the levels of pesticide residues in bell peppers do not pose a serious health risk to adults, but the acute health risk to children should be paid more attention.

Boron isotope variability related to boron speciation (change during uptake and transport) in bell pepper plants and SI traceable n(11 B)/n(10 B) ratios for plant reference materials.

Boron (B) is an essential micronutrient in plants and its isotope variations are used to gain insights into plant metabolism, which is important for crop plant cultivation. B isotope variations were used to trace intra-plant fractionation mechanisms in response to the B concentration in the irrigation water spanning the range from B depletion to toxic levels. A fully validated analytical procedure based on multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), sample decomposition and B matrix separation was applied to study B isotope fractionation. The validation was accomplished by establishing a complete uncertainty budget and by applying reference materials, yielding expanded measurement uncertainties of 0.8‰ for pure boric acid solutions and ≤1.5‰ for processed samples. With this validated procedure SI traceable B isotope amount ratios were determined in plant reference materials for the first time. The B isotope compositions of irrigation water and bell pepper samples suggest passive diffusion of the heavy 11 B isotope into the roots during low to high B concentrations while uptake of the light 10 B isotope was promoted during B depletion, probably by active processes. A systematic enrichment of the heavy 11 B isotope in higher located plant parts was observed (average Δ11 Bleaf-roots = 20.3 ± 2.8‰ (1 SD)), possibly by a facilitated transport of the heavy 11 B isotope to growing meristems by B transporters. The B isotopes can be used to identify plant metabolism in response to the B concentration in the irrigation water and during intra-plant B transfer. The large B isotope fractionation within the plants demonstrates the importance of biological B cycling for the global B cycle.

Influence of delayed cooling on quality of bell pepper (Capsicum annuum L.) stored in a controlled chamber

Improper postharvest handling, including delaying cooling, is a big concern for maintaining the freshness of fruit and vegetables in the postharvest supply chain. The objective of this study was to investigate the influence of short delays in cooling on some important quality parameters such as physiological weight loss, firmness, total soluble solids (TSS), and color (L*, h°, and C*) values of bell peppers stored in a controlled chamber. Bell peppers treated with three different treatments showed a gradual physiological weight loss of 1.46%, 3.18%, and 3.14% after a storage period of 15 days with: immediate storage (IS) after harvest in a controlled chamber, delaying storage (DS), leaving bell pepper without cover for one day, and under cover (DSC) separately in a greenhouse and then storing them in the controlled chamber, respectively. Over the storage period, slower firmness reduction (19.88%) of the IS treated bell peppers was observed compared to other bell pepper samples with delayed cooling. Bell peppers that underwent IS treatment showed lower changes in TSS (°Bx) values (6.89 to 7.24) compared to other treatments during the storage period. Fewer changes in color (L*, h°, and C*) values were found with IS treated bell peppers. Overall changes in the assessed quality parameters of bell pepper samples were slower with IS treatment than delayed cooling treatments throughout the storage period. This study provides significant information on the handling of harvested bell pepper in a favorable environment before transportation to processing and storage centers.

Determination of fungicides in bell pepper using solid-liquid extraction with low temperature partitioning

A novel method based on solid-liquid extraction with low temperature partition combined with gas chromatography with electron capture detection was established for the determination and quantification of fungicides (azoxystrobin, chlorothalonil and difenoconazole) in bell pepper (Capsicum annum L.). The performance of the method was assessed by studying selectivity, limits of detection and quantification, linearity, accuracy, and precision. Linearity (r > 0.99) was achieved for all compounds when calibration was performed, and the limits of quantification were below the tolerance levels of fungicides set by Brazilian legislation, the European Union, and the Codex Alimentarius. The average recoveries ranged between 97 and 108%, with relative standard deviations ≤12.2%. The proposed analytical method has been successfully applied for the analysis of real bell peppers samples cultivated in Viçosa city, Minas Gerais State, Southeastern Brazil. The residual fungicide concentration in the bell pepper samples was azoxystrobin (0.12 ± 0.01 mg kg−1), difenoconazole (0.18 ± 0.01 mg kg−1) and chlorothalonil (1.73 ± 0.02 mg kg−1).

Magnetite-sporopollenin/graphene oxide as new preconcentration adsorbent for removal of polar organophosphorus pesticides in vegetables.

In this study, a new magnetic adsorbent based on magnetite-sporopollenin/graphene oxide (Fe3O4-SP/GO) was successfully developed. The adsorbent was applied for magnetic solid phase extraction (MSPE) of three selected polar organophosphorus pesticides (OPPs), namely, dimethoate, phenthoate, and phosphamidon, prior to gas chromatography analysis with electron capture detection (GC-μECD). The Fe3O4-SP/GO adsorbent combines the advantages of superior adsorption capability of the modified sporopollenin (SP) with graphene oxide (GO) and magnetite (Fe3O4) for easy isolation from sample solution. Several MSPE parameters were optimized. Under optimized conditions, excellent linearity (R2 ≥ 0.9994) was achieved using matrix match calibration in the range of 0.1 to 500ngmL-1. The limit of detection (LOD) method (S/N = 3) was from 0.02 to 0.05ngmL-1. The developed Fe3O4-SP/GO MSPE method was successfully applied for the determination of these three polar OPPs in cucumber, long beans, bell pepper, and tomato samples. Good recoveries (81.0-120.0%) and good relative standard deviation (RSD) (1.4-7.8%, n = 3) were obtained for the spiked OPPs (1ngmL-1) from real samples. This study is beneficial for adsorptive removal of toxic pesticide compounds from vegetable samples.

Characterization of Pepper leafroll chlorosis virus, a New Polerovirus Causing Yellowing Disease of Bell Pepper in Saudi Arabia.

During the growing seasons of 2014 through 2016, a total of 336 leaf samples from bell pepper (showing leafroll and interveinal yellowing) and arable weeds were collected from Riyadh region, Saudi Arabia. The use of a polerovirus generic reverse transcription (RT)-PCR assay confirmed their presence in the bell pepper samples. Sequencing of the generic amplicon revealed high similarity (87.6 to 98.1% in nt) with four poleroviruses; Tobacco vein distorting virus, Pepper vein yellows virus, Pepper yellows virus, and Pepper yellow leaf curl virus. To further characterize one of these isolates (105D), a larger part of the genome (∼1,300 nt) spanning approximately from the 3' end of ORF2 to the middle of ORF3, was amplified and sequenced. Blasting the resulting sequence revealed the low amino acid and nucleotide identity percentages in the coat protein and movement protein partial genes with viruses deposited in GenBank. Next-generation sequence was used to acquire a larger part of the genome, which resulted in the reconstruction of isolate 105D's partial genome (5,496 nt). Sequence similarity analysis revealed the presence of a divergent polerovirus isolate belonging to a new species that was tentatively named Pepper leafroll chlorosis virus (PeLRCV). Using a specific RT-PCR assay for this isolate confirmed the presence of this new viral species in the symptomatic peppers. Aphid transmission experiments showed that PeLRCV is vectored by Aphis gossypii and that it can infect at least five out of the 15 different plants species tested. Based on our findings, PeLRCV is a new member of genus Polerovirus in the family Luteoviridae.

Effect of environment and vibration on quality change of bell pepper (Capsicum annum L.)

Discoloration and dehydration are crucial problems associated with quality of bell pepper (Capsicum annuum L.). Color and weight loss of the bell pepper were measured at different vibration levels, storage environments and storage periods. Vibration tests were carried out at different ‘g’ levels from normal to the worst-case for 180 sec on the initial day. The effect of two different storage environments (10°C, 90 % RH and 18°C, 40 % RH) for four time periods (1, 4, 7 and 10 days) were observed. At 18°C, 40 % RH storage environment, more weight loss and duller color were observed. In the 10°C, 90 % RH storage environment, the group of bell pepper sample having 12 g level vibration had significantly much more weight loss compared to other groups. In this storage environment, most of bell pepper samples maintained vivid color. Storage life and fruit quality of bell pepper were affected by storage temperatures, humidity and duration. The results showed that high g level vibration, high temperature, and low humidity environment during harvesting and storage process of the bell pepper should be avoided.