• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.643-647
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• 2004

Natural antimicrobial substance from peanut (Arachis hypogaea) shells was isolated and structurally elucidated. Peanut shells were extracted with methanol (MeOH) and concentrated in vacuo, MeOH extract was solvent-fractionated with ethyl acetate (EtOAc) and various buffer to obtain EtOAc acidic, neutral, and phenolic fractions. EtOAc neutral fraction, which showed antimicrobial activity, was purified through silica gel adsorption column, Sephadex LH-20 column, ODS column, and high performance liquid chromatographies, and its active substance was isolated and identified as pratensein (3',5,7-trihydroxy-4'-methoxyisoflavone) by spectroscopic methods of proton-nuclear magnetic resonance, mass spectrometry, and nuclear overhauser enhancement spectroscopy.

• The Plant Pathology Journal
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• v.20 no.1
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• pp.75-80
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• 2004

In an attempt to develop effective biocontrol system for management of stem rot disease in groundnut, 57 bacterial isolates and 13 isolates of Trichoderma spp. were evaluated for their antagonistic activity against Sclerotium rolfsii. The antagonists were selected based on their ability to inhibit the external growth of S. rolfsii from infected groundnut seeds. Four isolates of Pseudomonas fluorescens, GB 4, GB 8, GB 10 and GB 27, and T. viride pq 1 were identified as potent antagonists of S. rolfsii. T. viride pq 1 produced extracellular chitinase and parasitized the mycelium of S. rolfsii. Under controlled environment conditions, P. fluorescens GB 10, GB 27, T. viride pq 1 and the systemic fungicide Thiram(equation omitted) reduced the mortality of S. rolfsii inoculated to groundnut seedlings by 58.0％, 55.9％, 70.0％ and 25.9％, respectively compared to control. In vitro growth of P. fluorescens GB 10 and GB 27 was compatible with T. viride pq 1 and Thiram(equation omitted). Integrated use of these two bacterial isolates with T. viride pq 1 or Thiram(equation omitted) improved their biocontrol efficacy. Combined application of either GB 10 or GB 27 with T. viride pq 1 was significantly effective than that with Thiram(equation omitted) in protecting groundnut seedlings from stem rot infection.

• Journal of the korean society of oceanography
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• v.34 no.3
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• pp.167-171
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• 1999

Since toxic Alexandrium catenella and non-toxic A. fraterculus are morphologically similar, they are difficult to discriminate under the light microscope. However, a novel technology, such as fluorescein isothiocyanate (FITC)-conjugated lectin probes enables easy and rapid differentiation. Toxic A. catenella bound seven different lectins, whereas the non-toxic A. fratercuzus did not bind Arachis hypogaea (PNA) lectin. In addition, Pseudo-nitrschia species in this study were also difficult to identify to species level with light microscope techniques, but it was possible to classify them using fluorescent lectins. Pseudo-nitzschia multistriata, P. subfraudulenta and P. pungens bound Canavalia ensiformis (ConA), whereas P. subpaclfica did not, and P. pungens also bound Ricinus communis (RCA). These results imply that lectin could be used as a critical tool in the differentiation of P. multistriata, P. subfraudulenta and P. pungens. However, P. subpacifica was not differentiated by the lectins tested. Therefore, it isconcluded that lectin probes are useful for discriminating toxic A. catenella from non-toxic A. fraterculus, and for the identification of some Pseudo-nitzschia species. In addition, this method has a great potential to speed and detection between non-toxic and toxic harmful algal blooms (HABs) in Korean biotoxin monitoring systems.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.5
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• pp.339-342
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• 2000

Near-infrared reflectance spectroscopy (NIRS) was used to estimate the lipid and protein contents in ground seed samples of perilla (Perilla frutescens Brit.) and peanut (Arachis hypogaea L.). A total of 46 perilla and 80 peanut calibration samples and 23 perilla and 46 pea. nut NIRS validation samples were used for NIRS equation development and validation, respectively. Validation of these NIRS equations showed a range of very low bias (-0.05 to 0.13 %) and standard error of prediction corrected for bias (0.224 to 0.803%) and very high coefficient of determination ($R^2$) (0.962 to 0.985). It was concluded that NIRS could be adapted as a mass screening method for lipid and protein contents in perilla and peanut seed.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.385-390
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• 2009

A resveratrol synthase (RS) gene was isolated from peanut (Arachis hypogaea, L. cv. Jinpoong) plants. This gene was placed under the control of the cauliflower mosaic virus 35S promoter (CaMV35S) and introduced into two Korean varieties of potato (Solanum tuberosum L. cvs. Jasim and Jowon) plants by Agrobacterium-mediated gene transfer. Putative transformants were screened by PCR with primers designed from CaMV 35S promoter, NOS terminator and RS gene. Most of selected transgenic potato plants showed the amplification of expected fragments by PCR of genomic DNA with gene-specific primers, while they were absent in untransformed control plants. Expression of the resveratrol synthase gene was also examined by northern blot analysis. The transformants showed a band which was lacking in the control plant, confirming that the introduced gene is transcribed into mRNA in the transformants. The strength of the band, which reflected the level of mRNA expression, differed among the individual transformants. Among the transformants obtained, the highest trans-resveratrol content in the transgenic young leaves of purple-fleshed "Jashim" was $2.11{\mu}gg^{-1}$ fresh weight and that in the microtubers in vitro of purple fleshed "Jashim" was $8.31{\mu}gg^{-1}$ fresh weight. This amount of resveratrol may have a positive biological effect on human health.

• The Plant Pathology Journal
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• v.18 no.4
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• pp.204-209
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• 2002

Andhra Pradesh is one of the major groundnut growing states in India. A total of 182 groundnut samples collected at harvesting from farmers fields in five districts, namely; Anantapur, Chittoor, Cuddapah, Kurnool, and Mahaboobnagar, during 1999 and 2000 rainy seasons were evaluated for the presence of mycotoxins (both aflatoxins and zearalenone) and toxigenic fungi. In samples collected from each district, average seed infection by Aspergillus flavus and Fusarium spp. was 11.9-18.3% and 5.6-12.8% in 1999, and 9.5-14.1% and 9.4-11.9% in 2000, respectively. Among the samples collected, 20.3% and 16.5% were contaminated with aflatoxin in 1999 and 2000, respectively, and in 11.4% and 8.7% of the seed samples collected in two seasons, the aflatoxin content was >30 $\mu\textrm{g}$/kg. An alarming aflatoxin content of 851.9$\mu\textrm{g}$/kg was found in samples collected from Anantapur district during the rainy season in 1999. Zearalenone was not detected in any of the samples collected in 1999, while 2 out of 103 samples collected in 2000 were contaminated with 35.1 and 129.4$\mu\textrm{g}$/kg. Under in vitro cultural conditions, 35.8% of the 173 A. flavus isolates collected from the groundnut samples produced aflatoxins at concentrations of 94.3-1598.6 ng/$\textrm{m}{\ell}$ and 3% of the 266 Fusarium spp. isolates produced 98.1-847.3 $\mu\textrm{g}$/g of zearalenone. The results emphasize the need for a more systematic and regular monitoring of pre-harvest aflatoxin contamination.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.374-378
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• 2002

To evaluate growth habits, fresh pod yield potential, and possibility of early and late seeding, seeding dates were extended from March 21 to June 20 by PE mulching and non-mulching. Soil temperature, under 5cm from surface, above 15$^{\circ}C$ at 10 a.m. in early seeding reached about March 25 in mulching and April 5 to April 12 in non-mulching. Days to emergence and first flowering were accelerated owing to increasing temperature, as seeding was delayed. Days to emergence according to seeding dates reduced 21 to 8 day in mulching and 33 to 10 day in non-mulching. Days to flowering were ranged from 51 to 26 day in mulching and from 69 to 32 day in non-mulching and differences between mulching and non-mulching on each seeding date had 18 to 4 days. Early seedings till April 21 had 160-170 flowers per plant for 8 weeks, while late seedings from May 21 increased more speedily with 200 flower for 6 weeks. Harvesting of fresh peanut, at 80 days after first flowering, was possible from Aug. 1 to Oct. 7 (133-108 days to harvest) by mulching and from Aug. 19 to Oct. 12 (151 to 114 days) by non-mulching. Yields between mulching and non-mulching in early seeding until April 21 had more difference, but in late seeding after May 21 was higher and showed insignificance. Pod setting periods by early and late seeding were about 3 weeks equally. In late seeding pod setting were almost concentrated for front 15 days. In spite of difference of fresh pod weight between two seeding times, the distributions of average of seed weight showed nearly same tendency.

• Korean Journal of Medicinal Crop Science
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• v.12 no.5
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• pp.406-414
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• 2004

Resveratrol, which is both a phytoalexin with antifungal activity and a phytochemical associated with reduced cancer risk and reduced cardiovascular disease, is synthesized in a limited number of plant species including peanut. Resveratrol synthesis is catalyzed by the enzyme stilbene synthase including resveratrol synthase (RS). Resveratrol synthase gene (RS3) obtained from peanut, Arachis hypogaea, Fabaceae has been transferred into chinese foxglove, Rehmannia glutinosa by using Agrobacterium mediated transformation. RS t-DNA introduced to chinese foxglove (R. glutinosa L) by transformation and its reaction product, $resveratrol-3-O-{\beta}-D-glucoside$ was isolated and characterized using HPLC. Also its biological effects was tested in inhibition of the lipid peroxidation of mouse LDL by glycosylated stilbenes derivatives obtained from transgenic plants. $Resveratrol-3-O-{\beta}-D-glucoside$ isolated from transgenic R. glutinosa L. showed antimicrobial activity of the growth inhibition zone against Escherichia coli and Salmonella typhimurium. Therefore, this compound can be contributed to be useful as a phytoalexin for plant health as well as a phytochemical for human health.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.295-301
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• 1992

Eight crop residues : 1, sorghum (Sorqhum bicolor) straw, 2, maize (Zea mays) straw, 3, cotton (Gossypium Sp.) straw, 4, sunflower (Helianthus Sp.) straw, 5, cotton (Gossypium Sp.) seed hulls, 6, groundnut (Archais hypogaea) hulls, 7, maize (Zea mays) cobs, 8, sugarcane (Saccharum officinarum) bagasse and two forest grasses 9, Heteropogan contortus dry grass and 10, Sehima nervosum dry grass were subjected to three physical processing 1, chopping (2-3 cm) 2, grinding (8 mm sieve) and 3, pelleting (10 mm die holes). The processed material was fed ad lib. Along with 250 g of concentrate mixture per head per day to 6 adult local goats and 16 adult Nellore rams in ten digestion experiments and finally assessed the nutritive value of the processed roughages by difference method. Grinding increased bulk density by 32.4 (cotton seed hulls, CSH) to 88.1% (Sehima dry grass) while pelleting of ground material increased bulk density by 53.9 (maize cobs) to 235.8% (maize straw). The average particle size ranged from $584.1/^U$ (sorghum straw) to $1467/^U$ (CSH). Modulus of uniformity ranged from 2:5:3 (sorghum straw) to 7:2:1 (CSH) while modulus of fineness ranged from 3.4 (sorghum straw) to 5.4 (CSH). Molasses absorbability was highest with cotton seed hulls and least with maize cobs. Pelleting increased DM intake of the residues except cotton seed hulls compared to grinding. Grinding of chopped material/unprocessed material increased DM intake on sorghum straw and cotton seed hulls. Sheep consumed more DM compared to goats on all the residues except sorghum and sunflower straws. Pelleting increased nutritive value of all the residues compared to grinding and chopping. However, no difference was observed in the nutritive value due to grinding and chopping. Goats performed better compared to sheep in utilizing the fibrous residues.

• The Plant Pathology Journal
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• v.20 no.1
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• pp.67-74
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• 2004

A complete understanding of the epidemiological factors required for optimum for disease development facilitates the design of effective and reliable screening techniques and also disease prediction models. An attempt was made to study the effects of different temperatures ($15-35^{\circ}C$) and leaf wetness periods (4-24 h) on the development of late leaf spot (LLS) in three groundnut genotypes differing in their susceptibility to LLS infection. Irrespective of the genotype, the disease progress evaluated based on different components of resistance was maximum between $15-20^{\circ}C$ and minimum between $20-25^{\circ}C$. At temperatures $\geq$$30^{\circ}C$, LLS development was insignificant. The overall severity of LLS increased with an increase in the leaf wetness period from 4 h to 12 h a day. Further increase of wetness period to 16 h resulted in a rapid increase in the severity. Thereafter, the disease severity gradually decreased with an increase in the wetness period. The effect of temperature and wetness periods on the individual component of disease quantification was not uniform compared between genotypes with different levels of susceptibility/resistance to LLS infection. The results of this study indicate that temperature and leaf wetness period are critical in late leaf spot screening programs since the expression of disease symptoms measured from disease initiation till defoliation, varied differently in the test genotypes with respect to change in these two parameters.