Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “peanut”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
PubMed2000

High relative humidity increases yield, harvest index, flowering, and gynophore growth of hydroponically grown peanut plants.

Growth chamber experiments were conducted to study the physiological and growth response of peanut (Arachis hypogaea L.) to 50% and 85% relative humidity (RH). The objective was to determine the effects of RH on pod and seed yield, harvest index, and flowering of peanut grown by the nutrient film technique (NFT). 'Georgia Red' peanut plants (14 days old) were planted into growth channels (0.15 x 0.15 x 1.2 m). Plants were spaced 25 cm apart with 15 cm between channels. A modified half-Hoagland solution with an additional 2 mM Ca was used. Solution pH was maintained between 6.4 and 6.7, and electrical conductivity (EC) ranged between 1100 and 1200 microS cm-1. Temperature regimes of 28/22 degrees C were maintained during the light/dark periods (12 hours each) with photosynthetic photon flux (PPF) at canopy level of 500 micromoles-m-2s-1. Foliage and pod fresh and dry weights, total seed yield, harvest index (HI), and seed maturity were greater at high than at low RH. Plants grown at 85% RH had greater total and individual leaflet area and stomatal conductance, flowered 3 days earlier and had a greater number of flowers reaching anthesis. Gynophores grew more rapidly at 85% than at 50% RH.

Arachis↗
PubMed2003

[Effects of potash fertilizer on nutrient absorption by peanut and its yield and benefit].

Studies in Jianghuai hilly region showed that at definite N and P levels, applying potash fertilizer could regulate the transportation and distribution of nutrients in peanut plants, accelerate their absorption of N, P and K, increase the dry matter accumulation in their reproductive organs, and increase their yield, quality, and disease resistance. For each 100 kg pod products, the absorption of N, P and K was 3.08-5.35 kg, 0.6-1.2 kg and 3.45-6.66 kg, respectively. The K absorption was the biggest, and it was accumulated mainly in nutritive organs. The absorbed N and P were mainly accumulated in pods and other reproductive organs. The contents of N, P and K in all organs were increased with increasing potassium levels, and the amount of increased K was the biggest. The yield and economic benefit were the highest when the amount of applied potassium reached to 150-180 kg.hm-2 and N:P:K = 2:1:2. The highest pod yield was 5425.5 kg.hm-2, the highest benefit was 13,878.7 yuan.hm-2, and the ratio of output/input reached 6.75:1. The yield and economic benefit of peanut were decreased obviously when the amount of applied potassium was over 225 kg.hm-2. Thus, the prescription of N150, P75 and K150 was recommended for the balance fertilization of peanut production in this region.

Absorption↗
PubMed2004

[Synthesis and degradation of the peanut storage proteins during seed development and germination].

Three polypeptides, 41 kD and 38.5 kD subunits of arachin and 60.5 kD subunit of conarachin in peanut (Arachis hypogaea L. Shanyou 523) seeds were purified by gel filtration and SDS-PAGE. Polyclonal antibodies against these subunits were raised in mice. Western blot showed that the subunits appeared in axes and cotyledons at the tissue differentiation stage. The 60.5 kD subunit was firstly synthesized and accumulated in considerable quantity in axes and cotyledons, and then the 41 kD and 38.5 kD subunits increased during the development of peanut embryos. The degradation patterns of these three subunits were different during the germination of peanut seeds. The 41 kD and 38.5 kD subunits in the axes and cotyledons were degraded earlier than the 60.5 kD subunit.

Allergens↗
PubMedDate not supplied

Structural and functional alterations in major peanut allergens caused by thermal processing.

The majority of foods that we eat are subjected to some type of processing either at home or by the manufacturer. The biochemical reactions that occur in foods as a result of thermal processing can be both beneficial and harmful. Here, we briefly review the effects of thermal processing and some of the effects of the Maillard reaction on the allergenicity of food proteins. Specifically, we focus on the known effects of roasting on the allergenic properties of peanut proteins and the contribution of Maillard reaction products or advanced glycation end products to these observed effects. The most thorough understanding of the effects of thermal processing on allergenicity involves the peanut proteins. Thermal processing alters specific biophysical and immunological properties of peanut proteins, such as structure, function, solubility, digestibility, immunoglobulin E (IgE) binding, and T-cell responses. A better understanding of the effects of thermal processing-induced biochemical and immunological alterations is of utmost importance for proper risk assessment of existing and newly introduced proteins in the food source, as well as development of effective diagnostic tools and therapeutic treatments for food allergy.

Allergens↗
PubMed2005

[Effects of soil water status on gas exchange of peanut and early rice leaves].

The gas exchange characteristics of peanut and early rice leaves were investigated in experimental plots under different soil water conditions over a long growth period. The results showed that at the branching stage of peanut, the stomatal conductance (Gs) and transpiration rate (Tr) decreased slightly under mild and moderate soil water stress, while the net photosynthetic rate (Pn) and leaf water use efficiency (WUE) increased. The Gs/Tr ratio also increased under mild water stress, but decreased under moderate water stress. At podding stage, the Gs, Tr, Gs/Tr ratio and Pn decreased, while WUE increased significantly under mild and moderate water stress. The peanut was suffered from water stress at its pod setting stage. At the grain filling stage of early rice, the Gs, Tr and Gs/Tr ratio fluctuated insignificantly under mild and moderate water stress, while Pn and WUE increased significantly, with an increase in grain yield under mild water stress. It's suggested that the combination of Gs and Gs/Tr ratio could be a reference index for crop water stress, namely, crops could be hazarded by water stress when Gs and Gs/Tr decreased synchronously.

Arachis↗
PubMed1991

Inhibition of chemically-induced skin carcinogenesis in mice by peanut oil preparations.

Epidermal hyperplasia and sebaceous gland destruction - good indicators of carcinogenic potential - were studied in short-term mouse skin experiments following application of BaP and TPA dissolved either in a peanut oil mixture or in acetone. Subsequently, the carcinogenicity of BaP and DMBA alone or in association with TPA was dissolved in the same vehicles, and determined in mouse long-term skin tests. In parallel, ODC activity and binding to DNA, RNA and proteins were examined in epidermal cells after exposure to TPA and BaP respectively. When the peanut oil excipient was used as a solvent, a complete inhibition of BaP and TPA activities was observed in short-term skin tests, as well as a complete inhibition of BaP, DMBA and TPA carcinogenicity in long-term tests. TPA-induced ODC activity was suppressed by the peanut oil mixture while BaP binding to nucleic acids and proteins of epidermal cells was only slightly inhibited. These results indicate that the excipient possesses anti-carcinogenic potentials for epidermal cells. The persistence of BaP binding to macromolecules in epidermal cells without tumor development suggests that the carcinogenic action of BaP may include both genotoxic and epigenetic mechanisms.

9,10-Dimethyl-1,2-benzanthracene↗
PubMedDate not supplied

Determination of aflatoxin concentrations in peanut butter by enzyme-linked immunosorbent assay (ELISA): study of three commercial ELISA kits.

Sixteen United Kingdom analytical laboratories participated in an evaluation of 3 commercially available enzyme-linked immunosorbent assay (ELISA) kits for analysis of aflatoxin in peanut butter. Each laboratory was sent 3 sets of 10 randomly numbered samples of peanut butter. Each set consisted of 5 pairs of undisclosed duplicates. Four of the sets of duplicates were naturally contaminated butters with "target" aflatoxin values (estimated by liquid chromatography) between 8 and 81 micrograms/kg. The fifth pair was a blank peanut butter containing approximately 3 micrograms/kg of total aflatoxins. A statistical treatment of the results of the study is presented, together with discussion of the relative merits of the different kits.

Aflatoxins↗
PubMed1986

[Replacement of peanut oil used for the fortification of sugar with vitamin A for other vegetable oils available in Central America].

The objective of this study was to determine the technical feasibility of replacing the peanut oil used in the preparation of the premix to fortify sugar with vitamin A, for other vegetable oils available in Central America. For this purpose, cottonseed, soybean, corn and African Palm oils were tested. Premixes were prepared using each one of the oils and stored for evaluation during a six-month period. A premix prepared with peanut oil was used as a control. It was found that the stability of vitamin A was similar in all premixes; less than 10% of the original activity was lost through the duration of the study. The physical characteristics of the premixes were also acceptable, with the exception of the one containing soybean oil which became caked and rancid. The peroxide content of the oils contained in the premixes increased throughout the study period. The lowest level of oxidation occurred in the premix made with African Palm oil. Its peroxide content changed only from 1.4 to 8.8 mEq/kg of oil. In contrast, that containing soybean oil showed the greatest change in peroxide from 2.8 to 130.0 mEq/kg of oil. It was concluded that it is indeed technically feasible to substitute the peanut oil by another vegetable oil, which should be low in peroxides and of high stability. Furthermore, it should not alter significantly the stability of the vitamin A contained in the premix during storage. On this basis, the African Palm oil was the most suitable one.

Arachis↗
PubMedDate not supplied

Optimum methanol concentration and solvent/peanut ratio for extraction of aflatoxin from raw peanuts by modified AOAC method II.

The amount of aflatoxin extracted from raw peanuts by using the water-slurry modification of AOAC Method II was determined for 49 different combinations of methanol concentrations and solvent/peanut ratio. Results indicate that the amount of aflatoxins B1 and B2 extracted from raw peanuts is a function of both methanol concentration and solvent/peanut ratio, and a cubic equation was developed, using regression techniques, to describe the combined effects. From the functional relationship, the predicted methanol concentration and solvent/peanut ratio that extracts the most aflatoxin B1 was computed to be 60.0% and 10.8 mL solvent/g peanuts, respectively. This combination extracted 12.1% more aflatoxin than did AOAC Method II.

Aflatoxins↗
PubMed1986

IgE-mediated allergy to peanut, cow's milk, and egg in children with special reference to maternal diet.

Nineteen children with IgE-mediated allergy associated with strongly positive prick skin tests and RASTs to peanut or cow's milk and/or egg were studied. Seventeen of the children had been breast fed, ten had been exclusively breast fed for a minimum of 5 months. Reactions to these foods occurred on first exposure to the food in all but one instance, suggesting that in 18 instances sensitization had occurred antenatally or via the breast. A retrospective inquiry indicated that most of the mothers had had a generous intake of the food(s) to which their children were sensitized, but mothers of sensitized children did not consume more of these foods than the mothers of non-sensitized children; moreover, avoidance of the foods (peanut in two instances and egg in one) did not ensure freedom from sensitization to peanut and/or egg. Breast feeding by itself cannot be guaranteed to protect against the development of food allergy.

Anaphylaxis↗
PubMed1985

Peanut shell colitis.

A 40-year-old physician experienced abdominal pain, loose stools, hematochezia, and anal discomfort with defecation associated with the daily consumption of 15 to 30 whole peanuts, including the shells. Thorough evaluation revealed only nonspecific colitis of the distal portion of the sigmoid colon and inflamed hemorrhoids. Discontinuation of whole peanut ingestion was associated with symptomatic, endoscopic, and histological resolution. In this patient, undigested peanut shells seem to have caused a nonspecific colitis, perhaps as the result of mechanical abrasion of the colonic mucosa.

Adult↗
PubMedDate not supplied

Liquid chromatographic analysis system for cyclopiazonic acid in peanuts.

A liquid chromatographic procedure has been developed for analysis of cyclopiazonic acid in peanuts. The chromatographic system specifies a C18 or C8 column loaded with 4-dodecyldiethylenetriamine and an aqueous mobile phase containing 4-dodecyldiethylenetriamine, zinc acetate, ammonium acetate, 2-propanol, and acetonitrile. Cyclopiazonic acid was extracted from peanuts with methanol-chloroform (20 + 80), partitioned into aqueous sodium bicarbonate, acidified, and back-extracted into dichloromethane. The limit of detection (280 nm UV) was approximately 4 ng and detector response was linear to at least 1 microgram pure cyclopiazonic acid. The recovery of cyclopiazonic acid from peanuts spiked at 68.9, 210, and 955 micrograms/kg was 85.9% (12.86% CV), 72.9% (6.43% CV), and 81.4% (0.40% CV), respectively. Calculation of the chromatographic peak parameters based on the exponentially modified Gaussian model indicated that the C18 column produced less peak skewing than did the C8 column.

Arachis↗
PubMed1983

Dilution errors in aflatoxin determinations caused by compounds extracted from peanuts.

Several methods have been developed to analyze peanuts for aflatoxin by using thin layer chromatography (TLC). These methods depend on solvent extraction of aflatoxin from a sample of the product. Unfortunately, solvent solutions used to extract aflatoxin from peanuts also extract measurable quantities of other compounds such as oils, fats, sugars, and protein. The volume of these extracted compounds causes error in measuring the proportion of the solvent solution analyzed for aflatoxin. Also, because the cleanup procedures for some methods are inadequate, the volume of some of these extracted compounds also causes error in measuring the proportion of the extracted aflatoxin placed on TLC plates. These 2 errors cause underestimation of aflatoxin concentrations by approximately 11, 14, and 5% for the CB method, the modified version of the BF method generally used for raw peanuts, and a water slurry method, respectively. The correction specified by the CB method for fats in the extraction solvent reduces the approximate error for the CB method from 11 to 1%.

Aflatoxins↗
PubMed1981

Determination of aflatoxin B1 in corn, wheat, and peanut butter by enzyme-linked immunosorbent assay and solid phase radioimmunoassay.

Determinations of aflatoxin B1 in corn, wheat, and peanut butter by an enzyme-linked immunoassay (ELISA) and a solid-phase radioimmunoassay (RIA) were compared. Samples spiked with 2.9-43.2 ppb B1 were subjected to AOAC extraction procedure 26.017 or 26.023. The extracts were concentrated, redissolved in methanol, diluted in phosphate-buffered saline with Tween 20, and directly analyzed for B1 by either ELISA or RIA. At 5.8 ppb or greater, recoveries for B1 in corn, wheat, and peanut butter samples were 80.0, 86.6, and 94.8% by ELISA and 61.0, 93.3, and 110.0% by RIA, respectively. Recoveries greater than 120% were obtained for the wheat and peanut butter samples spiked with 2.9 ppb aflatoxin B1 by the RIA method but not by ELISA. Overall results indicated that ELISA gave more consistent data, relatively lower standard deviations, and lower coefficients of variation than did RIA. Analysis of 3 samples naturally contaminated with aflatoxins revealed that the ELISA data were comparable to those obtained by other established chemical methods.

Aflatoxin B1↗
PubMed1982

Comparison of rapid high pressure liquid chromatographic and CB methods for determination of aflatoxins in corn and peanuts.

A method is described for the rapid determination of aflatoxins in corn and peanut samples by high pressure liquid chromatography. The method was compared with the current CB method (AOAC 26.026). For 7 samples of corn and 14 samples of peanut meal and peanut butter, the correlation between methods is 0.991, and no significant difference exist between methods, using the Student's t-test at 15.7% alpha-risk.

Aflatoxins↗
PubMed1980

[Effects of soluble carbohydrates from several tropical foods (cassava, peanuts, coconut and papaya) on calcium utilization in the rat].

Ethanolic extracts containing soluble sugars were prepared from four foods : cassava, peanut, coconut and papaye. Six-month-old rats were given by stomach tube 10 mM CaCl2 solution (+ 45Ca) containing a carbohydrate. Depending on the group, the carbohydrate was glucose or melibiose or raffinose at 200 mM concentration, or one ethanolic extract. Blood samples were taken at different times after the administration and plasma radioactivity was measured. Rats were sacrificed at 24 hours; femur radioactivity was used as a measure of calcium absorption. Extracts of cassava, peanut, and papaye were the more patent in promoting calcium absorption. Extracts of coconut were less effective. This physiological activity of the extracts was correlated with the nature of sugars, identified by paper chromatography. Cassava contained raffinose, peanut included fructose, raffinose and stachyose. Fructose was abundant in papaye but in little quantity in coconut. The present experiments or earlier works had showed that these sugars enhanced calcium utilization.

Animals↗
PubMedDate not supplied

Extraction of aflatoxins from naturally contaminated peanuts with different solvents and solvent/peanut ratios.

A study was conducted to compare the extraction efficiencies of aflatoxins (B1, B2, G1, and G2) from low, medium, and high concentrations (approximately 10, 100, and 1000 ppb, respectively) of naturally contaminated peanut samples by using different solvents and solvent-to-peanut sample ratios. Solvents used were 80:20 methanol/water at 2:1, 3:1, and 5:1 solvent to sample ratios; 60:40 methanol/water at 5:1 solvent to sample ratio; and 90:10 acetonitrile/water at 2:1 and 4:1 solvent to sample ratios. The solvents 80:20 methanol/water at a 3:1 ratio of solvent to sample and 90:10 acetonitrile/water at a 2:1 ratio were consistently more efficient than all other solvents, regardless of the aflatoxin concentration. The solvent 90:10 acetonitrile/water at a 4:1 solvent-to-sample ratio was consistently the least efficient regardless of aflatoxin concentration based on analytical results with liquid chromatography (LC). The results are relevant in selecting an appropriate extraction solvent for use at peanut grading points.

Aflatoxins↗
PubMed1994

Evidence for the presence of Mn(II) in a peanut peroxidase. An EPR study.

The characteristics of the paramagnetic centers of the main cationic isozyme of peanut peroxidase are analyzed using electron paramagnetic resonance. Two main paramagnetic species have been detected. The EPR spectrum of the native cationic peanut peroxidase shows features which correspond to those of high spin ferric heme iron. A second paramagnetic center has been identified as manganese (Mn2+). The EPR spectra of the reduced enzyme and its fluoride, cyano, carbon monoxide, thiolate and hydroxy derivatives have been studied. The signal attributed to Mn(II) disappeared after dialysis against 50 mM EDTA, which removed the Mn ions, as it was confirmed by atomic absorption spectroscopy. The disappearance of the Mn signal after the formation of the cyano, thiolate and hydroxy complexes suggest a transfer of electrons from the Mn(II) ions. The significance of manganese in the catalytic cycle of cationic peanut peroxidase discussed.

Arachis↗