Onion Bulb Extract Research Articles

Effect of Garlic and Onions Extract Enriched with Honey Treatment on the Lipid Profile, Biochemical and Hematological Biomarker Status in Healthy Women

The onion and the garlic are among the oldest cultivated plants, serving as food and medicinal uses. The present study was aimed to investigate the effect of honey, onion (Allium cepa) bulb and garlic (Allium sativum) clove extracts on the cardiovascular risque biomarker in healthy women. In a 15 days treatment, 20 women were divided into two groups (n=10), the first group is the group of control (reference) and the other group is women receive aqueous extract of mixt compound (honey, garlic and onions) (test) for 15 days. Some biochemical and hematological parameters were analyzed. Results obtained show that Cholesterol (p <0.05), Triglyceride (p <0.01) and serum calcium level were significantly decreased in the test group compared to reference group however, the level of Creatinine was significantly increased (p <0.05) in test group compared to reference group. Our results demonstrated also that there was no significant change (p≥0.05) in all hematological parameters levels in test group compared to reference group. From the results of the study we can conclude that onion, and garlic extracts enriched with bee honey have a protective effect on lipids profile. Thus, onion, and garlic are beneficial in the prevention of cardiovascular diseases.

Management of Lycoriella ingenua (Diptera: Sciaridae) on oyster mushroom (Pleurotus ostreatus) through different botanicals

Oyster mushroom cultivation may be adversely affected by insect pests, including dark-winged fungus gnats, Lycoriella ingenua Dufour. The experiment was conducted to study the efficacy of different botanicals against L. ingenua on oyster mushroom. Five treatments, i.e., neem aqueous extract (5%), onion bulb extract (4%), garlic bulb extract (4%), eucalyptus leaf extract (6%) and an untreated control were tested. The lowest number of L. ingenua adults 2.69 ± 0.10 was observed in the neem aqueous extract treatments followed by garlic bulb extract (2.89 ± 0.09), while highest number (6.17 ± 0.21) was observed in untreated control followed by eucalyptus leaf extract and onion bulb extract with 3.70 ± 0.08 and 3.39 ± 0.08 number of adults, respectively. Neem aqueous extract treated bags showed a significantly higher mean number of mushrooms (10.14 ± 0.34) compared to control (4.72 ± 0.26). The highest yield (422.6 ± 5.81 g) was obtained from neem aqueous extract treated bags while the lowest yield (198.6 ± 8.00 g) from control. The biological efficiency of oyster mushroom was highest (80.70 ± 0.84%) in neem aqueous extract treated bags while lowest (46.15 ± 2.44%) was observed from control. Similarly, highest moisture content (92.83 ± 1.38%) was recorded from neem aqueous extract treated bags, and lowest moisture content (64.78 ± 2.01%) was recorded from control. Neem aqueous extract reduced the infestation of L. ingenua adults and gave highest yield of mushroom. Therefore, it is recommended that it should be used in the IPM program against L. ingenua on oyster mushroom.

Onion bulb extract can both reverse and prevent colitis in mice via inhibition of pro-inflammatory signaling molecules and neutrophil activity.

Onion is one of the most commonly used plants in the traditional medicine for the treatment of various diseases. We recently demonstrated the anti-inflammatory properties of onion bulb extract (OBE) in reducing colitis severity in mice when administered at the same time of colitis induction. However, whether onion can reverse established colitis or even prevent its development has not been investigated. To test 1. whether OBE can reduce colitis severity when given either before (preventative approach) or after (treatment approach) colitis induction and if so, 2. what are the mechanisms by which onion can achieve these effects. Colitis was induced by dextran sulfate sodium (DSS) administration using treatment and preventative approaches. The severity of the inflammation was determined by the gross and histological assessments. The colonic level/activity of pro-inflammatory molecules and immune cell markers was assessed by immunofluorescence and western blotting analysis. In vitro neutrophil superoxide release and survival was assessed by chemilumenecense and Annexin-V/7AAD assays respectively. OBE treatment significantly reduced colitis severity in both approaches, the colonic expression/activity profile of pro-inflammatory molecules, inhibited WKYMVm-induced superoxide release, and increased spontaneous apoptosis of neutrophils in vitro. OBE can be used as an effective option in the prevention and/or the treatment of established colitis.

Onion Bulb Extract Downregulates EGFR/ERK1/2/AKT Signaling Pathway and Synergizes With Steroids to Inhibit Allergic Inflammation

The treatment of allergic diseases, such as asthma, with both conventional and novel therapies presents a challenge both in terms of optimal effect and cost. On the other hand, traditional therapies utilizing natural products such as onion have been in use for centuries with demonstrated efficacy and safety but without much knowledge of their mechanims of action. In this study, we investigated if the anti-inflammatory effects of onion bulb extract (OBE) are mediated via the modulation of the EGFR/ERK1/2/AKT signaling pathway, and whether OBE can synergise with steroids to produce greater anti-inflammatory actions. Treatment with OBE inhibited the house dust mite (HDM)-induced increased phosphorylation of EGFR, ERK1/2 and AKT which resulted in the inhibition of HDM-induced increase in airway cellular influx, perivascular and peribronchial inflammation, goblet cell hyper/metaplasia, and also inhibited ex vivo eosinophil chemotaxis. Moreover, treatment with a combination of a low dose OBE and low dose dexamethasone resulted in a significant inhibition of the HDM-induced cellular influx, perivascular and peribronchial inflammation, goblet cell hyper/metaplasia, and increased the pERK1/2 levels, whereas neither treatment, when given alone, had any discernible effects. This study therefore shows that inhibition of the EGFR/ERK1/2/AKT-dependent signaling pathway is one of the key mechanisms by which OBE can mediate its anti-inflammatory effects in diseases such as asthma. Importantly, this study also demonstrates that combining OBE with steroids results in significantly enhanced anti-inflammatory effects. This action may have important potential implications for future asthma therapy.

Evaluation of botanicals against growth of Rhizoctonia solani under in vitro condition

Rhizoctonia solaniis a multiphagous widely distributed plant pathogen. Web blight caused by Rhizoctonia solani causes huge yield loses in urdbean (Vigna mungo). All the commercially grown varieties are susceptible. Being a typical soil borne fungus, its management through chemicals is expensive and not feasible, because of the physiological heterogeneity of the soil and other edaphic factors etc. Integrated approaches of the disease management are paying more attentiveness in terms of sustainability. The study was conducted at Department of Plant Pathology, College of Agriculture, Jabalpur, Jawaharlal Nehru Krishi Vishwavidyalaya (M.P) during 2018-19. It was carried out to know the efficacy of different botanicals on the mycelial growth of Rhizoctonia solani under in vitro condition. From the present study it could be concluded that all eight tested phytoextracts evaluated for their efficacy inhibiting R. solaniat different concentration of 10% and 20% under in vitro conditions using poisoned food technique significantly inhibited the growth of R. solani. The maximum percent inhibition in growth was recorded by onion and garlic bulb extracts.

Formulation and Physical Characterization of Onion (Allium ascalonicum L) Bulb Extract in Cream Using Tween 80 and Span 60 as the Emulgator

In Indonesia, it is not uncommon to find children who suffer from fever which can occur due to the change of weather from the rainy season during the dry season or vice versa. Communities in rural areas generally use onion (Allium ascalonicum L) to relieve fever in children. Cream preparations are made by varying the concentration of the emulgator to determine the effect of different concentrations of the emulgator on the physical characteristics of the cream preparation. The emulgator used is tween 80 and span 60 with a concentration of Formula 1: 3.5%, Formula 2: 3.75%, formula 3: 4%. Physical evaluations carried out in this study were organoleptic, pH, homogeneity, cream washability, cream type, viscosity, spreadability, adhesion, and freeze-thaw tests. The results of the study it can be concluded that the differences in the concentration of the emulgator can affect the physical characteristics of the cream preparation, namely in the spreading test and the adhesion test shows that F3 (4%) can reduce the spreadability of the cream preparation but can be attached to a long time when compared to F1 (3.5%) and F2 (3.75%). The physically optimal cream preparation formula is F1 and F2 because it meets all the requirements in the evaluation test.
 
 Keywords: Cream, onion, emulgator, physical characteristics

The Effect of Dayak Onion Bulb Ethanol Extract (Sisyrinchium palmifolium L.) on Triglyceride Level and Aorta Histopathology in Diabetes Melitus White Rat Induced by Alloxan

The high prevalence of diabetes mellitus in Indonesia has made antidiabetic treatment efforts increasingly popular. In addition, the many side effects caused by the use of chemical drugs, triggered the development of research on herbal therapy. The purpose of this study was to determine the effectiveness of Dayak onion bulb extract in reducing two-hour postprandial blood glucose, triglyceride levels, and the amount of lipid vacuoles in aorta blood vessels of diabetic rat. The long-term goal of this study is the creation of innovation products in the form of standardized herbs as complementary therapies that can be used daily by the community, so that the risk of morbidity can be reduced. The research design used was randomized control group pretest posttest design. The results of blood glucose analysis showed that there were significant differences between the positive control group with the 400 mg/KgBW and 800 mg/KgBW extract group, with a significance value of 0,000. In the extract group, 400 mg/KgBW with 800 mg/KgBW extract group showed no significant difference with a significance value of 0.390. The results of the analysis of triglyceride levels showed no significant difference between the positive control group with the 400 mg/KgBW extract group, with a significance value of 0.981. However, there were significant differences between the positive control group with the 800 mg/KgBW extract group with a significance value of 0.025. Between the 400 mg/KgBW and 800 mg/KgBW extract groups, there was a difference with a significance value of 0.024. Aorta histopathology results showed that there was a significant difference in the number of lipid vacuoles between the positive control group and the 400 mg/KgBW extract group and 800 mg/KgBW extract group. Based on the research, it can be concluded that the extract dose of 400 mg/KgBW is a dose that is able to influence the decrease in blood glucose levels, triglycerides and the amount of lipid vacuoles in the aorta blood vessels.

Evolvement of nutraceutical onion plants engineered for resveratrol biosynthetic pathway

Genetically engineered onion expressing codon-optimized VvSTS1 gene accumulated stilbenes and extended life span in yeast and can serve as potential nutraceutical. Resveratrol (RV) is a natural polyphenolic compound found in certain plant species including grapes. RV is well known for its nutraceutical properties and to assuage several disease conditions. Onion is the second most consumed vegetable worldwide and contains large quantities of precursor molecules, malonyl-CoA and para-coumaroyl-CoA that are needed for RV biosynthesis. The present study reports the development of nutraceutical onion by engineering RV biosynthetic pathway. A codon-optimized grapevine synthetic stilbene synthase gene (VvSTS1) was synthesized using native grapevine sequence. Six-week-old healthy yellowish compact nodular calli were co-cultivated with Agrobacterium tumefaciens harbouring pCAMBIA1300-hpt II-CaMV35S-VvSTS1-nos. PCR analysis revealed the presence of VvSTS1 and hpt II genes in putative transgenics. Southern blot analysis confirmed the integration of VvSTS1 gene and independent nature of transformants. LC-ESI-HRMS analysis revealed the accumulation of variable quantities of RV (24.98-50.18µg/g FW) and its glycosylated form polydatin (33.6-67.15µg/g FW) in both leaves and bulbs, respectively, indicating the successful engineering of RV biosynthetic pathway into onion. The transgenic onion bulb extracts extended the life span in haploid yeast. The transgenic onion accumulating RV and polydatin, developed for the first of its kind, may serve as a potential nutraceutical resource.

Onion bulb extract reduces colitis severity in mice via modulation of colonic inflammatory pathways and the apoptotic machinery

Ethnopharmacological relevanceThe use of nutraceutical-based products has increased in recent years due to their demonstrated efficacy and their good safety profile. Onion is one of the most commonly used plants in the traditional medicine for the management of various conditions including inflammatory and gastrointestinal diseases. However, little is known regarding the molecular mechanism of the anti-inflammatory effects of onion particularly in inflammatory bowel disease (IBD). Aim of the studyTo test the anti-inflammatory effects of onion bulb extract (OBE) in an IBD mouse model and the molecular mechanisms responsible for these effects such as modulation of the expression and/or the activity profile of various pro-inflammatory molecules. Materials and methodsColitis was induced in mice by dextran sulfate sodium (DSS) daily administration for 5 days. Animals were sacrificed, colons were removed and the severity of the inflammation was determined by the gross and histological assessments. The colonic level/activity of various cytokines and chemokines were measured using proteome profiling-based assay, western blotting, and immunofluorescence techniques. ResultsDSS-induced colitis was significantly reduced by the daily OBE treatment and 5-aminosalicylic acid (5-ASA, positive control), particularly at 100–200 mg/kg doses, at both the gross and histological levels. OBE was also shown to reduce colonic expression and activity of several pro-inflammatory molecules and signaling pathways, such as mitogen activated protein kinase family, mammalian target of rapamycin, cyclooxygenase-2, and tissue inhibitors of metalloproteinases. In addition, OBE reduced the expression of interferon-γ, various C–C and C-X-C chemokines, and molecules involved in the apoptotic machinery such as cytochrome c, caspase-3 and -8, B-cell lymphoma-extra-large and −2. ConclusionsOBE showed anti-inflammatory actions in IBD mouse model, which is attributed, in part, to the modulation of the expression and the activity of important pro-inflammatory molecules and signaling pathways involved in the inflammatory response. These data suggest that OBE may be a promising lead in the therapeutic management of IBD.

Pengaruh Pemberian Ekstrak Umbi Bawang Dayak (Eleutherine palmifolia L. Merr.) Terhadap Kadar Mda (Malondialdehid) Serum Tikus Putih (Rattus norvegicus) Jantan Galur Wistar Yang Diinduksi Parasetamol

<h2>ABSTRACT</h2><p><strong>Background:</strong> Paracetamol induced hepatotoxic effect because paracetamol increased production of N-acetyl-para-benzoquinone imine (NAPQI). Dayak onion contains flavonoids that inhibits cytochrome P450 activity, increases Glutation S-transferase (GST) activity, and scavenges free radicals.</p><p><strong>Method</strong><strong>: </strong>This study used 24 male wistar rats (<em>Rattus norvegicus</em>) divided into 3 groups: group of rats without paracetamol induction, group of rats induced by 1750mg/kgBW paracetamol on 14th day, and group of rats given 300mg/kgBW dayak onion bulb extract (<em>Eleutherine palmifolia</em> L. Merr) for 14 days and induced by 1750 mg/kgBW paracetamol on 14th day. <strong></strong></p><p><strong>Result</strong><strong>: </strong>The result of One Way Anova showed that serum malondialdehyde level of group of rats induced by paracetamol ( =129,063±42,0497mg/dl) was significantly higher (p=0.006) than group of rats without paracetamol induction ( =85,688±15,9976mg/dl). Serum malondialdehyde (MDA) level of group of rats given dayak onion bulb extract induced by paracetamol ( =118,500±19,4054mg/dl) was not significantly lower (p=0,463) than group of rats induced by paracetamol ( =129,063±42,0497mg/dl).</p><p><strong>Conclusion:</strong> The conclusion of this study showed that paracetamol significantly increased serum malondialdehyde (MDA) level and dayak onion bulb extract was not significantly decreased serum malondialdehyde (MDA) level.</p><p><strong>Keywords: </strong><em>Eleutherine palmifolia</em> L. Merr, malondialdehyde, paracetamol</p>

Effect of natural products on the production and activity of Clostridium difficile toxins in vitro

Clostridium difficile infection is a toxin-mediated disease of the colon. C. difficile virulence is primarily attributed to the production of toxin A and toxin B; thus this study was aimed to investigate the effect of a range of natural products on the production and activity of C. difficile toxins in vitro. Twenty-two natural products were investigated against four C. difficile strains. The activity of products against toxins was determined using Vero and HT-29 cells cytotoxicity and neutral red uptake assays. The indirect effect of products on toxin-mediated cytotoxicity was determined using the same cell lines. The effect of seven products on toxin production by C. difficile was determined using ELISA. Zingerone (0.3 mg/ml) protected both cell lines from C. difficile cytopathic effects, confirmed by the neutral red uptake assay (P < 0.05). Three Leptospermum honeys (4% w/v), fresh onion bulb extract (12.5% v/v) and trans-cinnamaldehyde (0.005% v/v) all reduced toxin production and activity significantly (P ≤ 0.023). Garlic clove powder (4.7 mg/ml) only reduced toxin activity (P ≤ 0.047). Overall, several natural products had activity against C. difficile toxins in vitro encouraging further investigation against C. difficile toxins in vivo.

Bioavailability of Quercetin from Onion Extracts after Intraruminal Application in Cows.

The aim of the present study was to investigate the bioavailability of quercetin from onion bulb (OB) and onion skin (OS) extracts in ruminants. Three non-lactating cows equipped with a permanent rumen fistula intraruminally received equimolar amounts of quercetin as either aglycone, rutin, or OB or OS extract, respectively, at a dose of 50 mg of quercetin equivalents/kg of body weight. Blood samples were drawn before and frequently within the 24 h period after application of the respective substance. Quercetin and quercetin metabolites with an intact flavonol structure (kaempferol, isorhamnetin, and tamarixetin) were analyzed in plasma samples by high-performance liquid chromatography with fluorescence detection. All quercetin sources administered resulted in a fast increase of the plasma concentrations of quercetin and total flavonols (sum of quercetin and its metabolites), followed by a rapid decline, whereby significant higher concentrations occurred with OB extract and rutin compared to quercetin aglycone and OS extract, respectively. The results clearly demonstrate a higher systemic availability of quercetin from OB extract and rutin. Taken together, OB extract with a high content of quercetin glucosides is an interesting source for the application of quercetin to ruminants.

Effects of natural products on several stages of the spore cycle of Clostridium difficile in vitro.

To investigate the effect of natural products on the spore cycle of Clostridium difficile invitro. Twenty-two natural products were investigated using four C. difficile strains. Effects on sporulation, determined using microscopy and a conventional spore recovery assay, showed that fresh onion bulb extract (6·3% vv-1 ) and coconut oil (8% vv-1 ) inhibited sporulation in all four isolates by 66-86% and 51-88%, respectively, compared to untreated controls. Fresh ginger rhizome extract (25% vv-1 ) was also inhibitory, although to a lesser extent. Using a standard spore germination and outgrowth assay, germination was unaffected by the 22 products, whereas outgrowth was significantly reduced by artichoke extract (18·8mgml-1 ), fresh onion bulb extract (25% vv-1 ), Leptospermum honeys (8% wv-1 ) and allicin (75mgml-1 ; P<0·01). Sporicidal activity, investigated using a standard plate recovery assay, was minimal. Three of the 22 natural products (13%) showed inhibitory effects on sporulation of C. difficile and six products (27%) reduced vegetative outgrowth of C. difficile. This study shows the potential of natural products to inhibit different stages of C. difficile sporulation and encourages further investigation in this field.

Biosynthesis and Characterization of Zinc Oxide Nanoparticles using Onion Bulb Extract

Biosynthesis and Characterization of Zinc Oxide Nanoparticles using Onion Bulb Extract

EFEKTIVITAS DAYA HAMBAT BAKTERI EKSTRAK BAWANG DAYAK TERSTANDARISASI FLAVONOID TERHADAP Enterococcus Faecalis (In vitro)

Background: Enterococcus faecalis is a bacterium which most often found on the wall of the root canal after the root canal treatment. It can be eliminated by NaOCl solution with high concentrations of 5,25%, this can cause toxic effects of the network around it. Dayak onion (Eleutherine palmifolia (L) Merr ) has antibacterial substances resulting active compound content one of it is flavonoid. Purpose: This study aims to determine the differences antibacterial activity of Dayak onion bulb which contains flavonoid compound on the growth of Enterococcus faecalis. Method: This experimental research using post test only with group design with 6 treatments groups, namely Dayak onion bulb extract 20 mg/ml, 40 mg/ml, 60 mg/ml and 80 mg/ml with 5,25% NaOCl as positive control and ethanol 96%as negative control. Result: The results of calculation inhibitory zone obtained the most effective concentration is 80 mg/ml of 21,314 mm,which is the category of high inhibitory zone, but no bacterial growth higher than the NaOCl 5,25% with a mean inhibition zone is 24,416 mm. The analysis data using shpiro-wilk to test a normality test and homogeneity test using levene’s test data showed normal and homogeneous (p<0,05). The analysis data is using one way Anova test that show there is significant differences p=0,000 (p<0,05), then further post hoc LSD test showed significant differences between concentrations of extract of Dayak onion bulb, NaOCl 5,25% and ethanol 96% p=0,000 (p<0,05). Conclusion: there are differences in the antibacterial activity of dayak onion bulb which contains flavonoid compounds on the growth of enterococcus faecalis and inhibitory zone obtained the most effective concentration is 80 mg/ml of 21,314 mm, but no bacterial growth higher than the NaOCl 5,25% with a mean inhibition zone is 24,416 mm.

Light-Regulatory Effect on the Phytosynthesis of Silver Nanoparticles Using Aqueous Extract of Garlic (&lt;i&gt;Allium sativum&lt;/i&gt;) and Onion (&lt;i&gt;Allium cepa&lt;/i&gt;) Bulb

Green synthesis emerged as an exciting approach in the field of nanotechnology. Biogenesis of nanosilver is simple, eco-friendly, safe and cost-efficacious and therefore gaining impetus nowadays. An effort has been made to understand the possible induced mechanism for the biosynthesis of silver nanoparticles by exposing a mixture of 1 mM AgNO 3 with aqueous extracts of garlic ( Allium sativum ) and onion ( Allium cepa ) under light and dark conditions. In the synthesis of silver nanoparticles, components of garlic and onion bulb extract served both as capping and reducing agents, whereas the light acted as catalyst. Green synthesized silver nanoparticles were quantified spectrophotometrically at different time intervals. Scanning electron microscopy confirmed that biosynthesized nanoparticles were polydispersed, spherical in shape and under the size range of 100 nm. Light proved to be an stimulating factor in the green synthesis of silver nanoparticles which may vary from species to species.

Ekstrak Bawang Tiwai (Eleutherine Americana Merr) Sebagai Antioksidan Pada Minyak Kelapa

Tiwa i onion bulb extract (EBT) contain phenol compounds that be used as an antioxidant ingredients. U t ilizalion tiwai onion bulb extract as an antioxidant is expected to increase t h e value and u tili z ati on t iwai onion bulbs. This rese a rc h was con d ucte d to obtain tiwai onion bulb extrect concentration as antioxidant ingredients of coconut oil. Extraction process is done by adding 96% ethanol solvent /0 onion liwai flour and tnen incorporated into tile glass beaker. allowed to stand for 24 hours and then filtered to obtain a liquid extract. Rendement liwai onion bulb extract solvent 96% ethanol is 10,2%. The average value of total phenol content of onion bulb extract tiwai solvent 96% ethanol is 0 ,043± 0 ,001ppm. Tile liquid extract was t h en per f o rm e d vacuum evaporation and the obtained f u rt er extract ti wai and then put in oven vacuum. Extract obtained is then inserted i n to tne coconut oil, and then analyzed with the parameters of color, odor. proxide number and acid number , wit h storage t ime for 3 months. Based on test result, it is o bt eine d that the concentretstions of tiwai onion bulb extract 100-200 mg/kg was able to maintain storage time of coconut oil until the 3 mont period specified in the study.

EVALUATION OF PHYTOEXTRACTS AGAINST MACROPHOMINA PHASEOLINA (TASSI) GOID CAUSING ROOT ROT OF SESAME

Occurrence of root rot disease in sesame has become a major constraint for cultivation of sesame in Junagadh district of Gujarat State (India). Considering the fact, the following investigation was carried out for this pathological problem. The efficacy of various botanicals were evaluated against Macrophomina phaseolina (Tassi.) Goid causing root rot of sesame. The phytoextracts of nine plant species were evaluated in vitro by poisoned food technique against M. phaseolina. The extract of garlic cloves (Allium sativum L.) was proved excellent with maximum inhibiting (77.65 %) mycelial growth and scanty sclerotial formation followed by onion bulb extract (Allium cepa L.) (63.98%). while least growth inhibition (32.34 %) was recorded in ginger rhizome extract.

Compatibility study of isolates of Trichoderma spp. with plant extracts

The potential Trichoderma is an exceptionally good model of bio-control agent as it is ubiquitous, easy to isolate and culture multiply rapidly on many substrates. There are several mechanisms involved in Trichoderma antagonism namely antibiosis whereby the antagonistic fungus shows production of volatile metabolites including ethylene and acetone as well as diffusible antibiotics and environmentally safe and economically viable strategy for control of various plant diseases has led to an increased plant based products in agriculture. The results of neem leaves, garlic and onion bulb extracts significantly reduced the growth of isolates of Trichoderma species. It was also noted that an increase in the concentration (5 % to 15 %) resulted in subsequent decrease in growth of the isolates. The inhibition per cent at lower concentration i.e ., 5 per cent of neem, garlic and onion extracts was ranging from 20.89 to 27.99, 9.51 to 17.11 and 7.95 to 12.5, respectively. Whereas, at higher concentration i.e ., 15 per cent, it was 44.53 to 55.09, 34.59 to 39.86 and 31.56 to 39.55, respectively. The average per cent inhibition in mycelial growth of isolates species wise indicated that all the seven species were more or less similar regarding sensitivity towards tested plant extracts.

Total phenolics, antioxidant and xanthine oxidase inhibitory activity of three colored onions (Allium cepa L.)

Methanolic extracts from bulbs of three onion (Allium cepa L.) varieties: red (Pusa Red), white (Pusa White Round), and yellow (Arka Pitamber) and the CHCl 3, Et 2O, EtOAc, and n-BuOH fractions obtained from those extracts were investigated for their total phenolics and antioxidant activity. The antioxidant activity measurements, expressed as total antioxidant status (TAS), were 5.2–50.18, 2.2–35.6 and 3.5–42.2 mg ml−1 for red, white and yellow onion bulb extracts, respectively, as compared to trolox (IC 50, 40.2 mg ml−1). The total phenolic content of the samples was 62–186, 56–156 and 68–165 mg GAE ml−1 for red, white and yellow onion bulb extracts, respectively, with all solvents. There was a positive correlation between the total phenolic content and antioxidant activity for MeOH extracts and EtOAc fractions (R2=0.96, 0.8 respectively). Of the selected colored onion bulbs the red onion (IC 50=14.2 μg ml−1) revealed more potent xanthine oxidase inhibitory activity to those of yellow (IC 50=15.5 μg ml−1) and white onion (IC 50=17.0 μg ml−1) in vitro and as compared to control allopurinol (IC 50=10.5 μg ml−1). The kinetic study by xanthine oxidase revealed that the white and yellow onion extracts were non-competitive inhibitors, as Km values were constant, while Vmax consequently decreased with increased inhibitor concentration. In the red onion extract there was an increase in Km values while Vmax remained constant at all extract concentrations, thus confirming a competitive type of inhibition by the Lineweaver–Burk equation. These findings suggest that these onion varieties can be considered as potential sources of antioxidants and XO inhibitory agents.