Variability of arginine content and yield components in Valencia peanut germplasm.

Peanut seeds are rich in arginine, an amino acid that has several positive effects on human health. Establishing the genetic variability of arginine content in peanut will be useful for breeding programs that have high arginine as one of their goals. The objective of this study was to evaluate the variation of arginine content, pods/plant, seeds/pod, seed weight, and yield in Valencia peanut germplasm. One hundred and thirty peanut genotypes were grown under field condition for two years. A randomized complete block design with three replications was used for this study. Arginine content was analyzed in peanut seeds at harvest using spectrophotometry. Yield and yield components were recorded for each genotype. Significant differences in arginine content and yield components were found in the tested Valencia peanut germplasm. Arginine content ranged from 8.68-23.35 µg/g seed. Kremena was the best overall genotype of high arginine content, number of pods/plant, 100 seed weight and pod yield.

Fructan:fructan 1-fructosyltransferase and inulin hydrolase activities relating to inulin and soluble sugars in Jerusalem artichoke (Helianthus tuberosus Linn.) tubers during storage.

Influences of harvest time and storage conditions on activities of fructan:fructan1-fructosyltransferase (1-FFT) and inulin hydrolase (InH) in relation to inulin and soluble sugars of Jerusalem artichoke (Helianthus tuberosus L.) tubers were investigated. Maturity affected 1-FFT-activity, inulin contents, and inulin profiles of the tubers harvested between 30 and 70 days after flowering (DAF). Decreases in 1-FFT activity, high molecular weight inulin, and inulin content were observed in late-harvested tubers. The tubers harvested at 50 DAF had the highest inulin content (734.9 ± 20.5 g kg-1 DW) with a high degree of polymerization (28% of DP >30). During storage of the tubers, increases in InH activity (reached its peak at 15 days of storage) and gradual decreases in 1-FFT activity took placed. These changes were associated with inulin depolymerization, causing decreases in inulin content and increases in soluble sugars. As well, decreasing storage temperatures would retain high inulin content and keep low soluble sugars; and freezing at -18 °C would best retard 1-FFT, InH, and inulin changes.

Identification of peanut seed prolamins with an antifungal role by 2D-GE and drought treatment.

This work revealed peanut seed prolamins likely displaying a defensive role besides the known nitrogen storage. Drought stress and proteomic approaches were used in varieties of peanuts to explore the prolamin member in association with a test against Aspergillus flavus spore germination. The stress effect was showed by aerial biomass, leaf content of malondialdehyde, and seed contamination by A. flavus. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles were not informative for the antifungal polypeptides. From two-dimensional gel electrophoresis, the suspected polypeptides were those with pI 5.45-5.75 and sizes of 22.0-30.5 kDa specifically in Spanish-type peanuts. Regarding to the drought effect in most of these peanuts, the spot peak volume analysis deduced three novel prolamin-related antifungal polypeptides at pI 5.75-5.8 with 30.5, 27.5-28.5, and 22.0-22.5 kDa, which was confirmed after isoelectric purification at pH 5.60. The data could not yet conclude their correlation with resistance to drought and to seed infection by A. flavus.

Preparation of Inulin Powder from Jerusalem Artichoke (Helianthus tuberosus L.) Tuber.

The complete procedure for the production of inulin powder from Jerusalem artichoke tubers (JAT) was investigated. The procedure consists of isolation of inulin from JAT, elimination of color from the inulin extract and solidification. Washed tubers were first sliced, dried in a 60 °C oven for 10 h and then milled and sieved into a powder. Inulin was isolated from the JAT powder by hot water extraction using an accelerated solvent extractor (ASE). The effects of temperature and time for the extraction were investigated. The highest extraction efficiency was obtained at the extraction temperature of 80 °C for 20 min. The color of the extract was eliminated using ion exchange process with diethylaminoethyl cellulose as the sorbent. The inulin powder was subsequently obtained by freeze drying. Inulin content and inulin profiles were monitored to evaluate the efficiencies of the complete procedure. The inulin content was indirectly determined by spectrophotometry from free and total fructose measurements using potassium iodide. The inulin profile was monitored using high performance anion exchange chromatography equipped with integrated pulse amperometric detection (HPAEC-PAD). The proposed method provided the inulin production yield of 92.5%. The present procedure is fast, simple and effective for production of inulin powder from JAT. In addition, infrared spectra and some physico-chemical properties of the obtained inulin powder were determined and compared with the standard inulin.

The combination of multiple plant growth promotion and hydrolytic enzyme producing rhizobacteria and their effect on Jerusalem artichoke growth improvement.

Rhizobacteria are well recognized for their beneficial multifunctions as key promoters of plant development, suppressing pathogens, and improving soil health. In this study, experiments focused on characterizing the plant growth promotion (PGP) and extracellular hydrolase production traits of rhizobacteria, and their impact on Jerusalem artichoke growth. A total of 50 isolates proved capable of either direct PGP or hydrolase-producing traits. Two promising strains (Enterobacter cloacae S81 and Pseudomonas azotoformans C2-114) showed potential on phosphate and potassium solubilization, IAA production, and 1-aminocyclopropane-1-carboxylic acid deaminase activity and hydrolase production. A hydrolase-producing strain (Bacillus subtilis S42) was able to generate cellulase, protease, amylase, ß-glucosidase, and phosphatase. These three selected strains also gave positive results for indirect PGP traits such as siderophore, ammonia, oxalate oxidase, polyamine, exopolysaccharide, biofilm, motility, and tolerance to salinity and drought stress. Colonization was observed using a scanning electron microscope and rhizobacteria appeared at the root surface. Interestingly, inoculation with consortia strains (S42, S81, and C2-114) significantly increased all plant parameters, including height, biomass, root (length, surface, diameter, and volume), and tuber fresh weight. Therefore, we recommend that potential consortia of PGP and hydrolase-producing rhizobacteria be employed as a biofertilizer to improve soil and boost crop productivity.

Crop model determined mega-environments for cassava yield trials on paddy fields following rice.

The Cropping System Model (CSM)-MANIHOT-Cassava provides the opportunity to determine target environments for cassava (Manihot esculenta Crantz) yield trials by simulating growth and yield data for various environments. The aim of this research was to investigate whether cassava production on paddy fields in Northeast, Thailand could be grouped into mega-environments using the model. Simulations for four different cassava genotypes grown on paddy field following rice harvest was conducted for various soil types and the weather data from 1988 to 2017. The genotype main effect plus genotype by environment interaction (GGE biplot) technique was used to group the mega-environments. The analyses of yearly data showed inconsistent results across years for environment grouping and for the winning genotypes of the individual environment group. An analysis using GGE biplot with the average value of the simulated storage root dry weight (SDW) for 30 years indicated that all 41 environments were grouped into two different mega-environments. This study demonstrated the ability of the CSM-MANIHOT-Cassava to help identify the mega-environments for cassava yield trials on paddy field during off-season of rice that could help reduce both time and resources.

Single and co-inoculum of endophytic bacteria promote growth and yield of Jerusalem artichoke through upregulation of plant genes under drought stress.

Helianthus tuberosus L. (Jerusalem artichoke) produce inulin, a type of fructan, which possesses several biotechnology applications, e.g., sugar syrup, prebiotics, fiber in diabetic food, enabling blood sugar and cholesterol reduction. Drought reduces inulin accumulation in the tubers of Jerusalem artichoke as the plants protect themselves from this stress by induction of stress gene responses, effecting growth reduction. Endophytic bacteria are promising candidates to promote plant growth and yield particularly under abiotic stress. Therefore, three endophytic bacteria with plant growth promoting properties were examined for their ability to improve Jerusalem artichoke growth and yield under both well-watered and drought conditions when inoculated individually or in combinations in pot experiments with 2 factorial random complete block design. The interactions of the endophytic bacteria and plant host determined the differential gene expression in response to drought as revealed by quantitative polymerase chain reaction. Single inoculum of the endophytic bacteria increased the height, weight, root traits, and harvest index of Jerusalem artichoke compared to co-inocula under both well-watered and drought conditions. However, the co-inocula of Rossellomorea aquimaris strain 3.13 and Bacillus velezensis strain 5.18 proved to be a synergistic combination leading to high inulin accumulation; while the co-inocula of B. velezensis strain 5.18 and Micrococcus luteus strain 4.43 were not beneficial when used in combination. The genes, dehydrin like protein and ethylene responsive element binding factor, were upregulated in the plants inoculated with single inoculum and co-inocula of all endophytic bacteria during drought stress. Moreover, the gene expression of indole-3-acetic acid (IAA) amido synthetase were up-regulated in Jerusalem artichoke inoculated with M. luteus strain 4.43 during drought stress. The fructan:fructan 1-fructosyltransferase (1-FFT) was also stimulated by the endophytic bacteria particularly in drought condition; the results of this study could explain the relationship between endophytic bacteria and plant host for growth and yield promotion under well-watered and drought conditions.

Physiological and Proteomic Responses of Cassava to Short-Term Extreme Cool and Hot Temperature.

Temperature is one of the most critical factors affecting cassava metabolism and growth. This research was conducted to investigate the effects of short-term exposure to extreme cool (15 °C) and hot (45 °C) temperature on photosynthesis, biochemical and proteomics changes in potted plants of two cassava cultivars, namely Rayong 9 and Kasetsart 50. One-month-old plants were exposed to 15, 30, and 45 °C for 60 min in a temperature chamber under light intensity of 700 µmol m-2 s-1. Compared to the optimum temperature (30 °C), exposure to 15 °C resulted in 28% reduction in stomatal conductance (gs) and 62% reduction in net photosynthesis rate (Pn). In contrast, gs under 45 °C increased 2.61 folds, while Pn was reduced by 50%. The lower Pn but higher electron transport rate (ETR) of the cold-stressed plants indicated that a greater proportion of electrons was transported via alternative pathways to protect chloroplast from being damaged by reactive oxygen species (ROS). Moreover, malondialdehyde (MDA) contents, a marker related to the amount of ROS, were significantly higher at low temperature. Proteomics analysis revealed some interesting differentially expressed proteins (DEPs) including annexin, a multi-functional protein functioning in early events of heat stress signaling. In response to low-temperature stress, AP2/ERF domain-containing protein (a cold-related transcription factor) and glutaredoxin domain-containing protein (a component of redox signaling network under cold stress) were detected. Taken together, both cultivars were more sensitive to low than high temperature. Moreover, Rayong 9 displayed higher Pn under both temperature stresses, and was more efficient in controlling ROS under cold stress than Kasetsart 50.

Promoting growth and production of sunchoke (Helianthus tuberosus) by co-inoculation with phosphate solubilizing bacteria and arbuscular mycorrhizal fungi under drought.

Due to different functions of phosphate solubilizing bacteria (PSB) and arbuscular mycorrhizal fungi (AMF), their potential synergistic effects on enhancing plant growth and yield are worth investigating, especially under adverse conditions. This work focused on the isolation of PSB and characterization for their plant growth promoting properties under drought. The most efficient P solubilizing bacterium was isolated and identified as Burkholderia vietnamiensis strain KKUT8-1. Then, a factorial experiment on the performance of sunchoke (Helianthus tuberosus) was set up with four factors, viz., PSB (presence or absence of KKUT8-1), AMF (presence or absence of Rhizophagus aggregatus), rock phosphate (RP; added or not) and moisture (well-watered (WW) or drought (DS) conditions). Sunchoke performance was enhanced by the presence of AMF, whereas addition of PSB had a positive effect on SPAD values and inulin concentration. Drought reduced plant performance, while addition of RP reduced photosynthetic rate. There was little evidence for synergistic effects between PSB and AMF, except for SPAD values and inulin concentration. Plants that were co-inoculated with AMF and PSB had highest SPAD value, shoot diameter, leaf area, leaf number, chlorophyll concentration, plant biomass, tuber production, root growth and total soluble sugar concentration. Co-inoculated plants also had increased plant water status, reduced electrolyte leakage, and reduced malondialdehyde and proline concentration. Strain KKUT8-1 is the first strain of B. vietnamiensis capable of promoting growth and yield of sunchoke. Enhanced production of sunchoke by a combination of AMF and PSB was much better than the application of RP. Our finding offers an opportunity to develop combinations of biological inoculants for increasing the growth and production of sunchoke under drought in the future.

Dual-Purpose of the Winged Bean (Psophocarpus tetragonolobus (L.) DC.), the Neglected Tropical Legume, Based on Pod and Tuber Yields.

Winged beans (Psophocarpus tetragonolobus (L.) DC.) are grown as a vegetable legume crop in Thailand. All parts of the plant, including pods, seeds, leaves, flowers, and tubers are edible and are rich in protein and nutrients. Although the major consumption of winged bean is based on pod and tuber yields, only the people of Myanmar and Indonesia utilize winged bean tubers as food materials. The usefulness of the winged bean as an alternative crop for staple food and feed can shed some light on the impact of winged bean. Therefore, the evaluation of the dual purpose of the winged bean based on pod tuber yields is the objective of this study. In this study, ten-winged bean accessions-six accessions obtained from introduced sources and four accessions obtained from local Thai varieties-were laid out in randomized complete block design (RCBD) with three replications at the Agronomy Field Crop Station, Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand from September 2019 to April 2020 and from October 2020 to April 2021. Data, including total pod weight, number of pods, pod length, 10-pod weight, and tuber weight were recorded, and the proximate nutrient and mineral contents in the tubers were also determined. The results revealed that the principal effects of year (Y) and genotype (G) were significant for total pod weight and the number of pods. Moreover, the Y × G interactions were principal effects upon the total pod weights and tuber weights. The results indicated that superior genotype and appropriate environmental conditions are key elements in successful winged bean production for both pod and tuber yields. The winged bean accessions W099 and W018 were consistent in both experimental years for pod and tuber yields at 23.6 and 18.36 T/ha and 15.20 and 15.5 T/ha, respectively. Each accession also proved high in tuber protein content at 20.92% and 21.04%, respectively, as well as significant in fiber, energy, and minerals. The results suggest that the winged bean accessions W099 and W018 can be used for dual-purpose winged bean production in Thailand.

Bio-control of Stem Rot in Jerusalem Artichoke (Helianthus tuberosus L.) in Field Conditions.

Stem rot is a serious disease in Jerusalem artichoke (JA). To reduce the impact of this disease on yield and quality farmers often use fungicides, but this control method can be expensive and leave chemical residues. The objective of this study was to evaluate the efficacy of two biological control agents, Trichoderma harzianum T9 and Bacillus firmus BSR032 for control of Sclerotium rolfsii under field conditions. Four accessions of JA (HEL246, HEL65, JA47, and JA12) were treated or notreated with T. harzianum T9 and B. firmus BSR032 in a 4 × 2 × 2 factorial experiment in two fields (environments), one unfertilized and one fertilized. Plants were inoculated with S. rolfsii and disease was evaluated at 3-day intervals for 46 days. T. harzianum T9 and B. firmus BSR032 reduced disease incidence by 48% and 49%, respectively, whereas T. harzianum T9 + B. firmus BSR032 reduced disease incidence by 37%. The efficacy of T. harzianum T9 and B. firmus BSR032 for control of S. rolfsii was dependent on environments and genotypes. The expression of host plant resistance also depended on the environment. However, HEL246 showed consistently low disease incidence and severity index in both environments (fertilized and unfertilized). Individually, T. harzianum T9, B. firmus BSR032, or host plant resistance control stem rot caused by S. rolfsii in JA. However, no combination of these treatments provided more effective control than each alone.

Combination of arbuscular mycorrhizal fungi and phosphate solubilizing bacteria on growth and production of Helianthus tuberosus under field condition.

In this work, the effects of co-inoculation between an arbuscular mycorrhizal fungus (AMF) and a phosphate solubilizing bacteria (PSB) to promote the growth and production of sunchoke under field condition were investigated during 2016 and 2017. Four treatments were set up as follows: plants without inoculation, with AMF inoculation, with PSB inoculation and with co-inoculation of PSB and AMF. The results showed the presence of PSB and AMF colonization at the harvest stage in both years. This suggested the survival of PSB and successful AMF colonization throughout the experiments. According to correlation analysis, PSB positively affected AMF spore density and colonization rate. Also, both AMF and PSB positively correlated with growth and production of sunchoke. Co-inoculation could enhance various plant parameters. However, better results in 2016 were found in co-inoculation treatment, while AMF inoculation performed the best in 2017. All of these results suggested that our AMF and PSB could effectively promote growth and production of sunchoke under field conditions. Such effects were varied due to different environmental conditions each year. Note that this is the first study showing successful co-inoculation of AMF and PSB for promoting growth and yield of sunchoke in the real cultivation fields.

Co-Inoculation of an Endophytic and Arbuscular Mycorrhizal Fungus Improve Growth and Yield of Helianthus tuberosus L. under Field Condition.

Endophytic fungi (EPF) and arbuscular mycorrhizal fungi (AMF) symbioses can promote the growth and productivity of several types of plants. This work aimed to investigate the effect of co-inoculation of an EPF Exserohilum rostratum NMS1.5 and an AMF Glomus etunicatum UDCN52867 g.5 on the growth and yields of sunchoke (Helianthus tuberosus L.) compared to the effects of full-dose and half-dose chemical fertilizer (15-15-15) under field conditions. Several plant growth parameters of the co-inoculated plants were significantly higher than the other treatments. Remarkably, such an effect was relatively equal to that of the full-dose chemical fertilizers. Moreover, the co-inoculation of EPF and AMF significantly improved the tuber yield production, even better than the use of a chemical fertilizer. This is the first report to show that plant growth promoting effects of the co-inoculation of EPF and AMF were exceptionally greater than those of the chemical fertilizer. Therefore, our EPF and AMF could potentially be used as a biofertilizer for promoting the growth and yield of sunchoke in the fields.

Interaction between Phosphate Solubilizing Bacteria and Arbuscular Mycorrhizal Fungi on Growth Promotion and Tuber Inulin Content of Helianthus tuberosus L.

Arbuscular mycorrhizal fungi (AMF) and phosphate solubilizing bacteria (PSB) could interact synergistically because PSB solubilize sparingly available phosphorous compounds into orthophosphate that AMF can absorb and transport to the host plant. Little is known about the interactions between these two groups in terms of promoting Jerusalem artichoke, Helianthus tuberosus L., which is widely planted by farmers because of its high inulin content. Production depends mainly on synthetic fertilizers as source of plant nutrients. This study aimed to isolate and characterize PSB and investigate the effects of co-inoculation of AMF and PSB on plant performance and inulin accumulation. Isolate UDJA102x89-9, identified as Klebsiella variicola (KV), showed phosphate-solubilizing ability and produced high amounts of several organic acids in vitro and of indole-3-acetic acid (IAA). The experiment combined KV and two AMF species (Glomus multisubtensum (GM) and Rhizophagus intraradices (RI)). Co-inoculation of KV with RI, in combination with rock phosphate, showed the largest increases in plant growth and tuber inulin content, compared both to an unfertilized and fertilized control. This result would reveal whether the phosphate solubilization and IAA property of the PSB in vitro played a significant role in changing plant growth and production, and the available P was subsequently taken up and transported to plant roots by AMF. The high combined effect may have the potential for use by farmers in the future as a biofertilizer for inulin production by Helianthus tuberosus L.

Biological Control of Alternaria Leaf Spot Caused by Alternaria spp. in Jerusalem Artichoke (Helianthus tuberosus L.) under Two Fertilization Regimes.

The objectives of this study were to evaluate the efficacy of integrating resistant genotypes of Jerusalem artichoke with Trichoderma harzianum isolate T9 to control Alternaria leaf spot caused by Alternaria spp. under two fertilization regimes and to determine whether T9 application induced chitinase and ß-1,3-glucanase activity in Jerusalem artichoke leaves. Six Jerusalem artichoke varieties (resistant varieties JA15, JA86, and JA116 and susceptible varieties HEL246, HEL293, and JA109) and three disease control methods (a non-inoculated control, application of T. harzianum T9, and fungicide sprays (propiconazole at a rate of 30 mL/20 L of water, 375 ppm)) was conducted in two separate trials (different fertilization regimes) at the experimental farm of the Faculty of Agriculture, Khon Kaen University, Khon Kaen, Thailand. Resistant genotypes controlled Alternaria leaf spot effectively. Application of Trichoderma showed low efficacy to control Alternaria leaf spot, but in specific susceptible genotypes-HEL246 and HEL293-the application of Trichoderma could reduce disease severity up to 10%. The application of Trichoderma was associated with a rise in production of chitinase and ß-1,3-glucanase in HEL246 seedlings. The number of Trichoderma propagules in soil, as well as the extent of colonization of roots and leaves, were monitored. The results indicated that application of Trichoderma had higher propagules than non-inoculated control. Neither varietal resistance nor the disease control methods used in this study impacted the yield or yield components of Jerusalem artichoke.

Endophytic Bacteria Improve Root Traits, Biomass and Yield of Helianthus tuberosus L. under Normal and Deficit Water Conditions.

Drought is more concerned to be a huge problem for agriculture as it affects plant growth and yield. Endophytic bacteria act as plant growth promoting bacteria that have roles for improving plant growth under stress conditions. The properties of four strains of endophytic bacteria were determined under water deficit medium with 20% polyethylene glycol. Bacillus aquimaris strain 3.13 showed high 1-aminocyclopropane-1-carboxylate (ACC) deaminase production; Micrococcus luteus strain 4.43 produced indole acetic acid (IAA). Exopolysaccharide production was high in Bacillus methylotrophicus strain 5.18 while Bacillus sp. strain 5.2 did not show major properties for drought response. Inoculation of endophytic bacteria into plants, strain 3.13 and 4.43 increased height, shoot and root weight, root length, root diameter, root volume, root area and root surface of Jerusalem artichoke grown under water limitation, clearly shown in water supply at 1/3 of available water. These increases were caused by bacteria ACC deaminase and IAA production; moreover, strain 4.43 boosted leaf area and chlorophyll levels, leading to increased photosynthesis under drought at 60 days of planting. The harvest index was high in the treatment with strain 4.43 and 3.13 under 1/3 of available water, promoting tuber numbers and tuber weight. Inulin content was unchanged in the control between well-watered and drought conditions. In comparison, inulin levels were higher in the endophytic bacteria treatment under both conditions, although yields dipped under drought. Thus, the endophytic bacteria promoted in plant growth and yield under drought; they had outstanding function in the enhancement of inulin content under wellwatered condition.

Peanut testa extracts possessing histone deacetylase inhibitory activity induce apoptosis in cholangiocarcinoma cells.

Previous studies demonstrated that peanut testa extracts (KK4 and ICG15042) containing natural histone deacetylase (HDAC) inhibitors inhibited the growth of several human cancer cell lines via apoptosis induction. The aims of this study were to investigate the anti-proliferative effects and the mechanism(s) responsible for apoptosis induction mediated by these peanut testa extracts in human cholangiocarcinoma cell lines (KKU-M214 and KKU-100). The anti-proliferative effects were assessed by MTT assay. Apoptotic cell death and cell cycle arrest were analyzed by flow cytometry. The caspase activities were studied using colorimetric caspase activity assay and western blot analysis. Our results revealed that KK4 and ICG15042 extracts inhibited cell proliferation of both KKU-M214 and KKU-100 cells in a dose- and time-dependent manner, with IC50 values of 38.28 ±â€¯0.29 (KK4), 43.91 ±â€¯1.94 (ICG15042) µg/mL for KKU-M214 and 78.40 ±â€¯1.74 (KK4), 82.77 ±â€¯0.94 (ICG15042) µg/mL for KKU-100 at 72 h. Apoptosis induction by these peanut testa extracts were observed in both KKU-M214 and KKU-100 cells in a concentration-dependent manner. Moreover, the percentage of cells in the sub-G1 phase was significantly increased in both KKU-M214 and KKU-100 cells. Cell cycle arrest was not observed in other cell cycle phases. Activation of caspases 8 and 3 were apparent integral parts of apoptosis induction in both cells. Both peanut testa extracts also caused down-regulation of p53, p21, Bcl-2 and pERK1/2 protein expression in these cells. These results suggest that peanut testa extracts may be potential anti-cancer agents for cholangiocarcinoma chemoprevention or chemotherapy.

Cytotoxic effects of peanut phenolics possessing histone deacetylase inhibitory activity in breast and cervical cancer cell lines.

BACKGROUND: Epigenetic histone modifications are considered as a promising avenue for cancer preventive and therapeutic strategies. The purpose of this study was to evaluate the antiproliferative and histone deacetylase (HDAC) inhibitory activity of selected peanut phenolics, including p-coumaric acid, ferulic acid, sinapinic acid and resveratrol, in MCF-7 and HeLa cells. METHODS: The cytotoxic and HDAC inhibitory activities were assessed by MTT assays, flow cytometric analyses of cell cycle arrest and apoptosis induction, and western blotting. RESULTS: The results showed that all four phenolics inhibited proliferation of both MCF-7 and HeLa cells in a dose-dependent manner. Among the phenolics tested, resveratrol was the most effective in inhibiting growth of cancer cells. Treatment with all phenolics resulted in histone H3 hyperacetylation in both cell lines, indicating potential for HDAC inhibition. These phenolics induced apoptosis in both MCF-7 and HeLa cells in a concentration-dependent manner. Moreover, all phenolics induced G0/G1-phase arrest of the cell cycle in MCF-7 cells while p-coumaric and ferulic acids caused S-phase arrest in HeLa cells. Exposure to p-coumaric acid increased p53 and p21 expression but decreased CDK4 levels in both cell types, which could result in the observed G0/G1 arrest. Moreover, inhibition of ERK1/2 phosphorylation by ferulic acid and resveratrol contributed to cell growth inhibition. CONCLUSION: Peanut phenolics appear to influence the extent of histone acetylation in MCF-7 and HeLa cells, and this activity modulates multiple pathways that are implicated in cancer prevention.

Changes in Protein Expression in Peanut Leaves in the Response to Progressive Water Stress.

This investigation was carried out at the Department of Plant Science and Agricultural Resources, Khon Kaen University in the rainy season of 2011. The objective of this study was to identify proteins in leaves of drought-susceptible peanut plants when regulated by progressive water stresses. The drought-susceptible peanut plants of Khon Kaen 4 cultivar were grown in pots under controlled environment. At day 30 after seed emergence, the plants were subjected to stress conditions for 5 and 6 days. The results showed that withheld water supply for 5 and 6 days gave moderately and severely water stresses, respectively. Under moderate water stress conditions, two up-regulated and eight down-regulated proteins were attained. The up-regulated proteins were striated fibre assembling and flap endonuclease 1. The down-regulated proteins were peptidyl-prolyl cis-trans isomerase FKBP4, tRNA(Ile)-lysidine synthase, chloroplastic, chloroplastic thioredoxin F-type, cytidinedeaminase 7, ALF domain class transcription factor, nudix hydrolase 8, pentatricopeptide repeat super-family protein, putative and ribulose-1,5-bisphosphate carboxylase/oxygenase, a large sub-unit. Under severe water stress conditions, two proteins, i.e., tRNA(Ile) lysidine synthase, chloroplastic and ALF domain class transcription factor did not change their relative abundance significantly where it indicated drought acclimation. The remaining proteins displayed significant changes and the changes were the same as those found in the peanut leaves when deprived water for 5 days. Up-regulated proteins are responsible for alleviating oxidative damages to plant genome and mediating plants responsive to the environmental factors in providing mechanical support, barriers and a rapid transport route. Down-regulated proteins were associated with drought susceptibility of the Khon Kaen 4 peanut plants.

Extractions of High Quality RNA from the Seeds of Jerusalem Artichoke and Other Plant Species with High Levels of Starch and Lipid.

Jerusalem artichoke (Helianthus tuberosus L.) is an important tuber crop. However, Jerusalem artichoke seeds contain high levels of starch and lipid, making the extraction of high-quality RNA extremely difficult and the gene expression analysis challenging. This study was aimed to improve existing methods for extracting total RNA from Jerusalem artichoke dry seeds and to assess the applicability of the improved method in other plant species. Five RNA extraction methods were evaluated on Jerusalem artichoke seeds and two were modified. One modified method with the significant improvement was applied to assay seeds of diverse Jerusalem artichoke accessions, sunflower, rice, maize, peanut and marigold. The effectiveness of the improved method to extract total RNA from seeds was assessed using qPCR analysis of four selected genes. The improved method of Ma and Yang (2011) yielded a maximum RNA solubility and removed most interfering substances. The improved protocol generated 29 to 41 µg RNA/30 mg fresh weight. An A260/A280 ratio of 1.79 to 2.22 showed their RNA purity. Extracted RNA was effective for downstream applications such as first-stranded cDNA synthesis, cDNA cloning and qPCR. The improved method was also effective to extract total RNA from seeds of sunflower, rice, maize and peanut that are rich in polyphenols, lipids and polysaccharides.