Yellow Onion Research Articles

THE USE OF ONION PEEL EXTRACT TO INHIBIT THE THERMAL OXIDATION OF POLYETHYLENE

The paper studies experimentally the antioxidant activity of onion peel acetone extracts of three varieties (Albion F1, Kaba, Red Baron) in the inhibition process of polyethylene thermal oxidation. The onion varieties differ in the color of their surface scales (colorless (white onion), yellow-orange (yellow onion), red (red onion)) and in the antioxidant properties of their extracts: red onion> yellow onion >> white onion. The results correspond to the mass of the extracted substances. A different sequence of onion varieties has been obtained in terms of the inhibitory effectiveness of their extracts: yellow onion> red onion >> white onion. The comparison of the extracted onion peel extracts with the industrial antioxidant Irganox 1010 in terms of inhibitory efficiency has been carried out. The paper presents and analyzes the IR spectra of the extracts.
 An increase in the extraction time from 24 hours to 56 days leads to an increase in the antioxidant properties of the extracts of all three varieties, but an increase in the inhibition efficiency is noted only for Albion F1 onion peel extract. In Red Baron and Kaba varieties, the main part of biologically active substances with antioxidant action is extracted from the peel into acetone during the first days of extraction.

Investigation of phenolic compounds and antioxidant activity in red and yellow onions and a synergistic utilization of skin extract in modified atmosphere packaging of salmon (Salmo salar)

AbstractThis study investigated potentially synergetic effects of red onion skin extract and modified atmosphere packaging (MAP) on lipid oxidation of salmon. The skin and flesh of red and yellow onions were extracted with water at 25°C, 45°C, 65°C and 90°C, ethanol and acetone in water solutions. Total anthocyanin and polyphenol levels and antioxidant capacity were determined after extraction. Minced salmon samples were mixed with red onion skin extract (ROSE) and packaged under MAP at different O2 concentrations (0%, 5%, 10% and 15% of total package gas composition) with 40% CO2 and balance N2. Polyphenol recovery and antioxidant capacity increased for each sample as the extraction temperature increased with hot water use. Water extraction at 90°C provided higher extraction yields than ethanol and acetone in water solutions. The ROSE treatment of fish with MAP reduced lipid oxidation rates as evidenced by a decrease in peroxide value (43%) and thiobarbituric acid reactive substance (TBARS) (30%). The ROSE might effectively suppress the free radicals in a MAP system. A skin extract and MAP application might increase the shelf life of salmon.

Effect of Anthocyanins Extracted from Peanut Skins, Roselle Calyces and Outer Peels of Onions on Quality and Colour Stability of Yoghurt Beverages during Storage

Anthocyanin have been used as a natural food colourant and as a source of natural antioxidants. Aqueous extracts of dried roselle calyces, outer peels of yellow onions, and peanut skins were used as sources of anthocyanin and other functional components such as phenolic and flavonoid compounds to fortify yoghurt beverages. Antioxidants, total phenolics, total flavonoids and anthocyanin were estimated in the plant extracts. Colour stability was evaluated in yoghurt beverages fortified with anthocyanin extracted during the storage period at 4±1°C for three weeks. The highest amount of total phenolic content was observed in peanut skin extract (1.645 mgžml-1), followed by dry outer peels of onions (1.5 mgžml-1) and roselle calyces (1.3 mgžml-1). Dry outer peels of onions showed the highest flavonoid content compared with peanut skin and roselle calyces extract. The highest amount of total anthocyanin was observed in roselle calyces (3.877 mg 100 g-1), followed by aqueous extract of onions skin (0.635 mg 100 g-1). During the storage period at 4±1 °C for three weeks, yoghurt beverages physicochemical and functional properties had been evaluated. The anthocyanin improved the colour, appearance, and overall acceptability of fortified yoghurt beverages. The overall results suggested that it is possible to produce high-quality yoghurt beverages fortified by adding 0.2% extracts of dry peanut skins, dry roselle calyces, and dry outer peels of yellow onions, which obtaining colours degree of red-orange, cheery red, and orange-yellow, respectively, colour stability during the storage period at 4±1°C for three weeks.

Antioxidant effect of ethanolic onion (Allium cepa) husk extract in ageing rats.

The role of natural antioxidants in preventing of age-relating diseases is evident. The vegetable industry generates a large amount of waste, which is a good source of antioxidants.The aim of the study was the investigation of the antioxidant effect of long-term consumption of ethanolic yellow onion husk extract in ageing laboratory rodents.Twenty male Wistar albino rats were divided randomly into two groups (n = 10): a control group and an experimental group that received ethanolic yellow onion husk extract (2 mL/rat diluted with distilled water; activity of 4.44 µmol-equiv. quercetin) for 188 days. Oxygen radical absorbance capacity and ferric reducing antioxidant power assays were used to determine the total antioxidant capacity of the extract, which amounted to 941.4 ± 32.7 µmol equiv. Trolox/g raw material and 167.4 ± 16.4 µmol-equiv. quercetin/g raw material, respectively. Oral intake of the onion husk extract affected the indicators of the antioxidant system of the liver and the brain but not of the blood and plasma, mainly due to elevations in the activity of catalase and superoxide dismutase in the liver by 44.4% and 79.1%, respectively, and in the brain by three-fold and 79.1%, respectively.The availability, cheapness and high antioxidant potential of onion waste qualifies it a good source of functional ingredients and bioactive substances applicable in the food and pharmaceutical industries.

Onion husk (Állium cépa) as a promising source of natural antioxidants

The search for new sources of natural antioxidants is an important area of research. The total antioxidant capacities (TAC) of ethanol and aqueous extracts of yellow, red and white onion husks, rosemary and basil were determined by the Oxygen Radical Absorbance Capacity method using fluorometer Fluoroskan Ascent FL and the Ferric Reducing/Antioxidant Power spectrophotometer SF-2000 and expressed in µmol-equiv. Trolox/g of a sample and µmol-equiv. dihydroquercetin / g of a sample, respectively. Ethanol and aqueous extracts of red onion husk demonstrated the greatest TACs and amounted to 709.17±21.68 µmol-equiv. Trolox/g and 2048.83±64.97 µmol-equiv. Trolox/g, and these significantly exceeded the TACs of such popular spices in the food industry as basil and rosemary. TACs of both extracts of yellow onion husk were approximately equivalent to rosemary. Ethanol extracts of red and yellow onion husk demonstrated the greatest TACs and amounted to 2005.64±33.59 µmol-equiv. dihydroquercetin /g and 941.39±65.43 µmol-equiv. dihydroquercetin /g, respectively, and these significantly exceeded the corresponding TACs of basil and rosemary. TACs of aqueous extracts were approximately equivalent to rosemary, but below the TAC of basil. The absence of bright taste and aroma of red and yellow onion husk extracts, high total antioxidant capacity for neutralization of free radicals by both mechanisms of interaction, as well as the availability of raw materials in large scale confirms that this waste of the fruit and vegetable industry is a promising source of natural antioxidants.

β-lactoglobulin and its thermolysin derived hydrolysates on regulating selected biological functions of onion skin flavonoids through microencapsulation

ABSTRACT β-lactoglobulin and its thermolysin-derived hydrolysates were compared regarding the potential for microencapsulating of the flavonoids from yellow onion skins. Antioxidant activity of powders was of 500.28 ± 2.89 mMol Trolox/g dry weight (DW) for hydrolysates (P1) and 480.11 ± 4.45 mMol Trolox/g DW for whole protein (P2). Both powders showed antidiabetic activity against α-glucosidase, with inhibitory effect of 44.79 ± 0.58% for P1 and 32.76 ± 2.08% for P2. The bioinformatics analysis indicated that the Ala32-Ser37, Val59-Ile72, Leu111-Tyr118 and Val139-Ala148 amino acid sequences are particularly important for exerting potential antidiabetic activity. The finest powder was P2, with small 1–2 µm microspherosomes, whereas the peptides caused the agglutination of the flavonoids, leading to coacervates larger than 20 μm. Such an integrative approach might be useful in terms of recovering health-promoting bioactives from underutilized sources, such as onion skins and whey, contributing to the management and valorization of by-products, simultaneous with the development of innovative ingredients for functional applications.

Correction to: Evaluation of forty-five cultivars as affected by bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds of intermediate-day yellow onion (Allium cepa L.) in South Korea

Correction to: Evaluation of forty-five cultivars as affected by bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds of intermediate-day yellow onion (Allium cepa L.) in South Korea

Bovine β-lactoglobulin peptides as novel carriers for flavonoids extracted with supercritical fluids from yellow onion skins.

Our study describes in detail the binding mechanism between the main flavonoids that were extracted from onion skins by supercritical CO2 and peptides from whey proteins, from the perspective of obtaining multifunctional ingredients, with health-promoting benefits. The supercritical CO2 extract had 202.31± 11.56mg quercetin equivalents/g DW as the major flavonoid and antioxidant activity of 404.93±1.39mMTrolox/g DW. The experiments on thermolysin-derived peptides fluorescence quenching by flavonoids extract allowed estimating the binding parameters, in terms of binding constants, and the number of binding sites. The thermodynamic analysis indicated that the main forces involved in complex formation were hydrogen bonds and van der Waals interactions. Molecular docking tests indicated that peptide fluorescence quenching upon gradual addition of onion skin extract might be due to flavonoids binding by Val15 -Ser21 . All 7 to 14 amino acids long peptides appeared to have affinity toward quercetin-3,4'-O-diglucoside and quercetin-4'-O-monoglucoside. The study is important as a potential solution for reuse of valuable resources, underutilized, such as whey peptides and yellow onion skins flavonoids for efficient microencapsulation, as a holistic approach to deliver healthy and nutritious food. PRACTICAL APPLICATION: A growing interest was noticed in the last years in investigating the interactions between proteins and different biologically active compounds, such as to provide knowledge for efficient development of new food, pharmaceutical, and cosmetic products. Recent studies suggest that flavonoid-protein complexes may be designed to improve the functional performance of the flavonoids. The results obtained in this study bring certain benefits in terms of exploiting the bioactive potential of both flavonoids and bioactive peptides, for developing of formulas with improved functional properties.

Co-Microencapsulation of Flavonoids from Yellow Onion Skins and Lactic Acid Bacteria Lead to Multifunctional Ingredient for Nutraceutical and Pharmaceutics Applications.

In this study, flavonoids extracted from yellow onion skins and Lactobacillus casei were encapsulated in a combination of whey protein isolate, inulin and maltodextrin with an encapsulation efficiency of 84.82 ± 0.72% for flavonoids and 72.49 ± 0.11% for lactic acid bacteria. The obtained powder showed a flavonoid content of 89.49 ± 4.12 mg quercetin equivalents/g dry weight (DW) and an antioxidant activity of 39.27 ± 0.45 mM Trolox/g DW. The powder presented a significant antidiabetic and anti-inflammatory potential, with an inhibitory effect on α-amylase, lipase and lipoxygenase of 76.40 ± 2.30%, 82.58 ± 3.36% and 49.01 ± 0.62%, respectively. The results obtained for in vitro digestion showed that the coating materials have a protective effect on the flavonoids release. Cytotoxicity results indicated that the powder was cytocompatible up to a concentration of 500 μg/mL. The functional potential of the powder was tested by adding in a selected food matrix, highlighting a good stability of the phytochemicals, whereas an increase with 1 log cell forming unit (CFU)/g DW was observed after 21 days of storage. The obtained results are promising in the valorization of natural antioxidants in combination with lactic acid bacteria in order to develop multifunctional ingredients with value-added for food and pharmaceutics applications.

Evaluation of forty-five cultivars as affected by bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds of intermediate-day yellow onion (Allium cepa L.) in South Korea

We evaluated and classified forty five onion cultivars according to bulb initiation, bulb and scale characteristics, minerals and organic compounds contents, and storage quality in South Korea during 2016/2017 and 2017/2018 growing seasons. Field experiment was conducted in randomized block design with three replications. Bulb initiation ranged from 153 days after transplanting (DAT, April 2) to 177 DAT (April 26). Fresh bulb weight (FBW) and bulb index (BI) were 285.5 ± 18.5 g/individual, 0.93 ± 0.05, respectively. Number of scales (NS), number of center (NC), and scale thickness (ST) were 7.6 ± 0.2, 2.3 ± 0.2, and 5.5 ± 0.2 mm/scale, respectively. Chroma and Lightness of bulb skin were 27.1 ± 1.9, 61.2 ± 2.3, respectively. Storage loss (SL) on December 12 was 19.4 ± 5.9%. Nitrogen (N), Carbon (C) and sulfur (S) contents were 1.36 ± 0.14, 37.9 ± 3.2 and 0.40 ± 0.06 mg kg−1 on a fresh weight basis. Total soluble solids (TSS) and total phenolics content (TPC) were 8.6 ± 0.6 °Bx, 164.8 ± 15.6 mg GE kg−1 on a fresh weight basis. Days from transplanting to bulb initiation was significantly positively correlated with bulb height, NC, dry matter, N, C, S, TSS, TPC, total flavonoids content (TFC) etc., while it was negatively correlated with rot loss and SL. Dry matter content was significantly positively correlated with N, C, S, TSS, TPC, TFC etc., while it was negatively correlated with SL. Storage loss was negatively correlated with N, S, Potassium and TSS. Dendrogram of agglomerative hierarchical clustering for the forty five cultivars based on bulb initiation, bulb and scale characteristics, and bulb minerals and organic compounds contents classified five cultivar groups. Cluster 1 featured the earliest bulb initiation and the greatest SL. Cluster 2 featured the fewest NS and NR, and the thickest ST. Cluster 3 featured the greatest FBW, and the most NS and NC. Cluster 4 featured the greatest BI and the thinnest ST. Cluster 5 featured the lowest SL, and the highest minerals and antioxidant compounds contents. This information should be helpful for onion growers to decide onion cultivar and for onion breeders to promote new cultivars depending on their purpose.

Tailoring the Health-Promoting Potential of Protein Hydrolysate Derived from Fish Wastes and Flavonoids from Yellow Onion Skins: From Binding Mechanisms to Microencapsulated Functional Ingredients.

This study focuses on combining different bioprocessing tools in order to develop an in-depth engineering approach for enhancing the biological properties of two valuable food by-products, namely fish waste and yellow onion skins, in a single new bioactive formulation. Bone tissue from phytophagous carp (Hypophthalmichthys molitrix) was used to obtain bioactive peptides through papain-assisted hydrolysis. The peptides with molecular weight lower than 3 kDa were characterized through MALDI-ToF/ToF mass spectrometry and bioinformatics tools. As a prerequisite for microencapsulation, the ability of these peptides to bind the flavonoids extracted from yellow onion skins was further tested through fluorescence quenching measurements. The results obtained demonstrate a considerable binding potency with a binding value of 106 and also the presence of one single or one class of binding site during the interaction process of flavonoids with peptides, in which the main forces involved are hydrogen bonds and van der Waals interactions. In the freeze-drying microencapsulation process, an efficiency for total flavonoids of 88.68 ± 2.37% was obtained, considering the total flavonoids and total polyphenols from the powder of 75.72 ± 2.58 quercetin equivalents/g dry weight (DW) and 97.32 ± 2.80 gallic acid equivalents/g DW, respectively. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test on the L929 cell line cultivated in the presence of different concentrations of microencapsulated samples (0.05–1.5 mg/mL) proved no sign of cytotoxicity, the cell viability being over 80% for all the samples.

First report of Fusarium proliferatum causing necrotic leaf lesions and bulb rot on storage onion (Allium cepa) in southwestern Idaho.

In September 2014, a high rate of bulb rot (5-15% depending on producer) was reported across all cultivars developing early in the storage season in the onion producing region of southwestern Idaho. Spanish yellow onion bulbs cv. Vaquero displaying tan to light brown necrotic rot were obtained. The bulb rot originated in the neck and spread to successive scales (Figure 1). In August 2015, onion cv. Redwing and Vaquero were observed to have wet necrotic lesions developing on leaves in the field (Figure 2). Margins of necrotic tissue, 1-2 cm3, were excised, surface sterilized, plated on water agar medium and incubated at 24°C. Hyphal growth was sub-cultured from eight strains (A- D in 2014; E-H in 2015) to fresh potato dextrose agar to obtain pure cultures. Cultures were characteristic of Fusarium species as described by Nelson et al. (1983) with the presence of microconidia formed on polyphialides with macroconidia present. Primers ITS4-A1 and ITS5 primers (White et al. 1990); EF-1 and EF-2 (O'Donnell et al. 1998); and fRPB2-5F and fRPB2-7cR (Liu et al. 1999) were used to amplify regions of the ITS, elongation factor 1-α and the second largest subunit of DNA-directed RNA polymerase II. Amplicons were sequenced and analyzed using BLAST (https://www.ncbi.nlm.nih.gov/) and in combination using Pairwise DNA Alignment and Polyphasic Identification (http://www.westerdijkinstitute.nl/Fusarium/DefaultInfo.aspx?Page=Home) as described by O'Donnell et al. 2015. Analysis indicated that these strains are Fusarium proliferatum, which is part of the F. fujikuroi species complex (O'Donnell et al. 1998). Similarity (99.5%) was observed in pairwise analyses and the polyphasic identification clustering to representative F. proliferatum strain NRRL 22944 and others. Sequences were submitted to Genbank and registered accession numbers are found in Table 1. To complete Koch's postulates, cv. Vaquero onion bulbs were surface sterilized and injected with 3 × 105 microconidia into the shoulder of each bulb. Five bulbs were inoculated for each isolate, placed in a mesh bag, and incubated at 30°C in the dark. Five bulbs injected with sterile water and five non-inoculated bulbs served as controls. After 14 days, each bulb was sliced vertically down the center and inspected for rot. All eight strains induced tan to light brown necrotic rot symptoms in each inoculated bulb. No symptoms were observed for the water inoculated and the non-inoculated onion bulbs. A fungus was isolated from the necrotic tissue and confirmed to be F. proliferatum as described above. Ten µl aliquots containing 1 × 105 microconidia of F. proliferatum strains (C, E-H) were applied to leaves in triplicate of 12-week-old onion plants (cv. Vaquero) wounded with a 21-gauge needle. Water controls were included. Within three days lesions, with light chlorosis, began to form and quickly spread on the leaves. A fungus was isolated and confirmed to be F. proliferatum as described above. This is the first extensive description and identification of F. proliferatum causing bulb rot in storage in Idaho (Mohan et al. 1997). In addition, this is the first report of the fungus causing leaf infection in the field. These findings confirm F. proliferatum as the causal agent of the high incidence of bulb rot observed in 2014 and 2015. This bulb rot continues to occur in southwestern Idaho and since the pathogen can cause leaf infections growers are encouraged to be vigilant for both leaf lesions during the growing season and bulb rot in storage.

Determination of Organosulfides from Onion Oil.

Qualitative and semi-quantitative analysis of organosulfides extracted from oil obtained by steam distillation of yellow onions was performed by gas chromatography-mass spectrometry (GC-MS). The extraction efficiency of organosulfides from onion oil was evaluated across four solvents: dichloromethane; diethyl ether; n-pentane; and hexanes. Analysis of solvent extracted organosulfides by GC-MS provided qualitative results that support the use of dichloromethane over other solvents based on identification of 27 organosulfides from the dichloromethane extract as compared to 10 from diethyl ether; 19 from n-pentane; and 17 from hexanes. Semi-quantitative evaluation of organosulfides present in the dichloromethane extract was performed using diallyl disulfide as the internal reference standard. Three organosulfides were detected in the extract at ≥5 mg/kg; 18 organosulfides between 3–5 mg/kg; and six organosulfides at <3 mg/kg. The E/Z isomers of 1-propenyl propyl trisulfide were among the most prevalent components extracted from the onion oil across all solvents; and 3,6-diethyl-1,2,4,5-tetrathiane was among the most abundant organosulfides in all solvents except hexanes. The method described here for the extraction of organosulfides from steam distilled onion oil surveys common solvents to arrive at a qualitative and semi-quantitative method of analysis for agricultural products involving onions; onion oil; and secondary metabolites of Allium spp.

Enhanced Yield of Bioactivities from Onion (Allium cepa L.) Skin and Their Antioxidant and Anti-α-Amylase Activities.

There is increasing concern for reduction of the ecological impacts of industrial waste caused by fruits and vegetables. To reduce costs of onion waste disposal while obtaining value-added products, onion skin can be used to extract quercetin, a natural flavonoid with antioxidant, anti-inflammatory and anti-cancer effects. The aim was to optimize quercetin extraction from brown onion (Allium cepa L.) skin through investigation of the effects of different parameters on quercetin yield. Operational parameters for conventional maceration extraction and for ultrasound-assisted extraction were compared: solvent type, mass-to-liquid ratio, extraction time and temperature. Antioxidant capacity was determined using DPPH· radical scavenging assays and quercetin yield using HPLC/DAD. Anti-α-amylase activity of onion skin extracts was investigated using α-amylase inhibition assays. Optimal extraction conditions of quercetin from onion skin were obtained with maceration extraction, 50% ethanol, 1:100 mass-to-liquid ratio, 25 °C, for 15 min. Under these conditions, the antioxidant capacity (expressed as quercetin equivalents) was 18.7 mg/g and the mass fraction of quercetin was 7.96 mg/g. The onion skin extracts showed a dose-dependent relationship between dry extract concentration and α-amylase inhibition, which confirms that this onion skin extract can be considered as an anti-diabetes agent.

Evaluation of onion cultivars as affected by bulb maturity and bulb characteristics of intermediate-day yellow onions in South Korea

ABSTRACT This study evaluated the performance of 55 intermediate-day onion cultivars (Allium cepa L.) in southeastern Korea, and clustered the cultivars based on bulb maturity and marketable bulb yield (MBY). Days from transplanting to bulb initiation (DTB) ranged from 146 to 177. Fresh bulb weight (FBW) and MBY were lower in early or mid-maturing cultivars than in late-maturing ones. The cultivar ‘Eomcheongnan’ produced the greatest FBW and MBY in the mid-maturing cultivars. Of the late maturing cultivars, ‘Art’, ‘K-star’, ‘Okkimaru’, ‘Cheonjujunggo’, ‘Worldstar’, and ‘Johwang’ ranked for MBY with more than 73.0 Mg ha−1. Only 10 late-maturing cultivars including 6 cultivars with more than 73.0 Mg ha−1, ‘Dekanmaru’, ‘Newmars’, ‘Hanaro’ and ‘Strike’ had a significantly greater than 4 cultivars (‘Volve’, ‘SuperRich’, ‘Marathoner’, and ‘Gangwon 1 ho’) with the lowest MBY, which might be due to difference in maturity too short with 14–26 April for bulb initiation, and 3–13 June for harvest. Higher air temperature and lower rainfall during bulb development stage did not affect days from transplanting to harvest (DTH), but negatively affected FBW. In 47 cultivars except for early and mid-maturing cultivars which started bulb initiation before 10 April, MBY was positively correlated with only DTH (R = 0.401) and FBW (R = 0.960). All the 55 cultivars were classified into 5 clusters, but there were close distances in clusters among late-maturing cultivars.

Increased Flavonol Levels in Tobacco Expressing AcFLS Affect Flower Color and Root Growth

The onion (Allium cepa L.) flavonol synthase (AcFLS-HRB) gene, encoding an enzyme responsible for flavonol biosynthesis in yellow onion, was recently identified and enzymatically characterized. Here, we performed an in vivo feeding assay involving bacterial expression of AcFLS-HRB and observed that it exhibited both flavanone 3-hydroxylase (F3H) and FLS activity. Transgenic tobacco (Nicotiana tabacum) expressing AcFLS-HRB produced lighter-pink flowers compared to wild-type plants. In transgenic petals, AcFLS-HRB was highly expressed at the mRNA and protein levels, and most AcFLS-HRB protein accumulated in the insoluble microsomal fractions. High-performance liquid chromatography (HPLC) analysis showed that flavonol levels increased but anthocyanin levels decreased in transgenic petals, indicating that AcFLS-HRB is a functional gene in planta. Gene expression analysis showed the reduced transcript levels of general phenylpropanoid biosynthetic genes and flavonoid biosynthetic genes in AcFLS-HRB overexpressed tobacco petals. Additionally, transgenic tobacco plants at the seedling stages showed increased primary root and root hair length and enhanced quercetin signals in roots. Exogenous supplementation with quercetin 3-O-rutinoside (rutin) led to the same phenotypic changes in root growth, suggesting that rutin is the causal compound that promotes root growth in tobacco. Therefore, augmenting flavonol levels affects both flower color and root growth in tobacco.

English

The qualitative phytochemical analysis of oil, juice and dry forms of garlic and three species of onions (red, brown and white onions) was investigated. Samples of fresh and dried garlic, red, brown and white onions were prepared and analyzed. All the samples were analyzed for the presence of phytochemicals which include saponins, flavonoids, phenols, tannins, triterpenoids, cardiac glycosides, steroids and alkaloids. Results of the juice samples showed that garlic has the lowest phytochemical content while red and brown onions recorded the highest and similar phytochemical contents. All the samples gave positive results for saponins and cardiac glycosides. For the dry samples, garlic had the lowest phytochemicals while the red and brown onions had the highest. The oil extracts of garlic and white onions had lower phyto-nutrients while red and brown species still possessed higher phyto-nutrients with steroids and saponins present in all samples. This study concludes that brown onions has the highest phytonutrients in all forms and are recommended as the most preferred option in health and disease. &nbsp; Key words: Flavonoid, tannins, saponin,phytochemical, onions, garlic, Makurdi

First Report of Dickeya fangzhongdai Causing Soft Rot of Onion in New York State

In early July 2014, an outbreak of soft rot disease of onion (Allium cepa L.) occurred in Orange County, NY. Symptoms developed following rainy, hot, humid weather and included chlorosis, maceration of leaves, browning, and plant collapse within a few days. Bulbs from diseased plants appeared normal, but inner tissues were macerated. Disease was first apparent in a field of red onions (cv. Redwing); later yellow onions (cultivar unknown) in an adjacent field were symptomatic. Standard techniques were used to isolate bacteria from diseased red onion bulbs (Bonasera et al. 2017). Briefly, 14 onion bulbs were cut open with a disinfected knife, and diseased tissues were probed with sterile wooden applicators and streaked on onion extract medium agar (Zaid et al. 2012). Plates were incubated for 2 days at 28°C, and individual colonies were streaked to purity on Luria–Bertani (LB) agar. Small white bacterial colonies with irregular margins were obtained as the predominant type from three samples. A representative colony was identified as Dickeya sp. based on the sequence of a portion of its 16S rRNA gene amplified by fD1/rP2 (Weisburg et al. 1991). Several more colonies were assessed using ADE1 and ADE2 PCR primers specific to Dickeya genus (Nassar et al. 1996), which also indicated that these isolates belonged to the genus Dickeya. Genomic DNA of one of these colonies, AP6, was extracted and sequenced using an Illumina NextSeq500 by the Institute of Biotechnology at Cornell University. Raw reads were processed (Ma et al. 2019) and used for de novo assembly with SPAdes 1.12. The draft genome assembly resulted in 260 contigs, with an N50 size of 50,007 bp, totaling 5.11 Mbp, and it was deposited in GenBank as accession number VS. We conducted average nucleotide identity and in silico DNA-DNA hybridization tests to determine the species of Dickeya strain AP6 using Python package pyANI and GGDC (https://ggdc.dsmz.de), respectively. These analyses indicated that AP6 belongs to species Dickeya fangzhongdai. Koch’s postulates were completed with D. fangzhongdai AP6. Two leaves each of three 80-day-old, healthy-appearing, controlled environment-grown onion plants (cv. Fortress for the first replicate, cv. Redwing for the second and third replicates) were inoculated with D. fangzhongdai AP6. The leaves were first punctured with sterile toothpicks, and then the wound was smeared with bacteria grown overnight on LB agar. One plant was punched with sterile toothpicks as a negative control. Elongated lesions with water-soaking at the margins were observed around the inoculation sites after incubating for 24 h at 30°C; no symptoms were observed on control plants. Disease symptoms progressed very rapidly; after 72 h, all AP6-inoculated plants had collapsed completely, and foliage was quite water-soaked. The experiment was conducted three times. We isolated three isolates from water-soaked lesions 24 h after inoculation and used dnaX sequencing on one of the reisolated colonies to confirm that bacteria in the diseased tissue were identical to the D. fangzhongdai inoculum. D. fangzhongdai was first identified in China as causing bleeding canker necrosis on pear (Tian et al. 2016). D. fangzhongdai was reported to cause soft rot in Welsh onion in Taiwan (Tsai et al. 2019), diseased Phalaenopsis orchids in Slovenia and Aglaonema in St. Lucia, and was found in water samples from Scotland and Malaysia (Alic et al. 2018; Pritchard et al. 2013). Soft rot disease of onion was reported in the United States (Ceponis et al. 1986), but its causal organism had not been investigated thoroughly. Here we report that D. fangzhongdai caused an outbreak of soft rot of onions in Orange County, NY.

Protocatechuic acid and quercetin glucosides in onions attenuate changes induced by high fat diet in rats.

Yellow onion waste from industrial peeling was used to obtain three pure preparations: protocatechuic acid (PA), quercetin diglycosides (QD) and quercetin monoglycosides (QM). PA contained 61% protocatechuic acid, QD contained 35% quercetin diglucosides, mainly quercetin-3,4'-diglucoside, and QM contained 41% monoglucosides, mainly quercetin-4'-glucoside. The highest antioxidant activity was shown by PA. The effects of preparations on the digestive functions of the gastrointestinal tract of rats as well as the biochemical parameters and antioxidant capacity of the blood in model research on Wistar rats sustained by a high-fat diet were assessed (5 groups per 8 animals). The results of the present experiment showed that different onion phenolic preparations differently modulated the enzymatic activity of faecal (P < 0.001) and caecal (P < 0.001) microbiota. For instance, the QD preparation but not QM efficiently reduced the faecal and caecal bacterial β-glucuronidase activity. Both protocatechuic acid and quercetin monoglycosides showed a beneficial effect by regulating blood lipids (reduction of TC (P < 0.001) and TG (P < 0.001), non-HDL increase in HDL (P < 0.001)), thereby lowering the risk factors for atherosclerotic lesions AI (P = 0.038) and AII (P = 0.013). In addition, onion phenols showed a strong antioxidant effect, however, with a different mechanism: protocatechuic acid via serum ACL (P = 0.033) increase and hepatic GSSG (P = 0.070) decrease, QM via ACW (P < 0.001) increase and hepatic TBARS (P = 0.002) decrease, and QD via serum ACW increase and hepatic GSSG decrease. It can be concluded that onion polyphenols with a lower molar weight, i.e. QM more preferably affect the blood lipid profile than QD. However QD more efficiently reduced the faecal and caecal bacterial β-glucuronidase activity.

Faktor-faktor Yang Mempengaruhi Permintaan Bawang Merah Di Kota Medan

Shallot is a horticultural commodity classified as vegetable spices that serve as a seasoning for food and traditional medicine. The importance of shallot for cooking makes the demand for shallot continue to increase every year. This research aims to see what factors influence the demand for shallot in Medan City. This research was conducted in Medan Deli Market and Kemiri Market. Sampling used this research used the Accidental Sampling method, which determines the sample based on people who are accidentally encountered in the study area. The number of samples examined in this research is 40 samples of shallot consumers. This research uses Best Linear Unbiased Estimation and Multiple Linear Regression methods. The variables studied were the price of shallot, the income of consumers, the number of family members and the price of yellow onion. The result of this research indicates that the factor that influences the demand for shallot is the price of shallot, the income of consumers and the number of family members, while those that do not affect is the price of yellow onion.