Pea Sprouts Research Articles

The influence of light-emitting diodes on the phenolic compounds and antioxidant activities in pea sprouts

The effects of various light-emitting diodes (LEDs), such as red, blue, and yellow LED lamps, as well as white fluorescent lamps and darkness, on the levels of phenolic compounds and antioxidant activities in pea sprouts were evaluated. The total phenolic (TPC) and total flavonoid contents (TFC) of the pea sprouts under the blue and red LED light, as well as the white fluorescent lamps, were 1.46, 1.25, 1.45 times and 24.55, 21.01, 24.29 times, respectively, when compared to the dark environment control. The ABTS cation radical-scavenging activity, ferric reducing activity power (FRAP), and reducing power of the pea sprouts under blue LED light were 1.75, 3.52, and 1.97 times, respectively, compared to the control. The blue LED light significantly increased all of the individual phenolic contents when compared to the control. These results indicate that blue LED light should be recommended as a light source for enhancing the content of phenolic compounds.

Effect of Zinc Enrichment on Growth and Nutritional Quality in Pea Sprouts

Zinc (Zn) is essential in plant nutrition and a fundamental component. Zn deficiency causes 450,000 deaths of children under 5 years of age every year. The slight lack of Zn leads to more diseases in humans, such as anorexia, loss of appetite, smell and taste failure. Thus, biofortification is used to provide the Zn nutritional status of plant food. The present study was conducted to investigate the effects of exogenous application of Zn by soaking and spraying on Zn contents, nutrition composition and antioxidant capacity in sprout. The results showed that plant growth was gradually increased from 10 to 50 mg L-1 of Zn; the nutrient values were also incremented by Zn of certain concentrations; and applied Zn treatment improved the total antioxidant capacity and contents of free amino acid. However, when Zn was over 50 mg L-1, it resulted in reductions of nutrition value and antioxidant capacity, inhibiting the sprout growth. These results indicated that the optimal dose of Zn by soaking or spraying was 40-50 mg L-1; and the impact of spraying was better than that of soaking. It was effective to enrich Zn content in certain extent by soaking or spraying, which could increase the nutrition value and antioxidant capacity as functional foods.

The Effects of Light and Temperature on Biotin Synthesis in Pea Sprouts.

Biotin is an essential micronutrient, and is a cofactor for several carboxylases that are involved in the metabolism of glucose, fatty acids, and amino acids. Because plant cells can synthesize their own biotin, a wide variety of plant-based foods contains significant amounts of biotin; however, the influence of environmental conditions on the biotin content in plants remains largely unclear. In the present study, we investigated the effects of different cultivation conditions on the biotin content and biotin synthesis in pea sprouts (Pisum sativum). In the experiment, the pea sprouts were removed from their cotyledons and cultivated by hydroponics under five different lighting and temperature conditions (control [25ºC, 12-h light/12-h dark cycle], low light [25ºC, 4-h light/20-h dark cycle], dark [25ºC, 24 h dark], low temperature [12ºC, 12-h light/12-h dark cycle], and cold [6ºC, 12-h light/12-h dark cycle]) for 10 d. Compared to the biotin content of pea sprouts under the control conditions, the biotin contents of pea sprouts under the low-light, dark, and cold conditions had significantly decreased. The dark group showed the lowest biotin content among the groups. Expression of the biotin synthase gene (bio2) was also significantly decreased under the dark and cold conditions compared to the control condition, in a manner similar to that observed for the biotin content. No significant differences in the adenosine triphosphate content were observed among the groups. These results indicate that environmental conditions such as light and temperature modulate the biotin content of pea plant tissues by regulating the expression of biotin synthase.

Evaluation of Pea (Pisum sativum L.) Genetic Resources for Sprout and Analysis of Optimum Culture Condition for Pea Sprout

본 연구는 완두나물로 활용 가능한 유전자원을 선발하고, 그에 적합한 재배조건을 설정하고자 재배 온도 및 기간에 따른 완두나물의 재배특성 및 항산화 활성을 분석하여 완두를 이용한 채소용 나물 최적 재배 조건을 구명하고자 실시하였다. 1. 완두 유전자원 38점 중 완두 나물로 이용 가능한 자원으로 PI269803, PI343278, PI343283, PI343300와 PI343307을 1차적으로 선발하였다. 2. 1차 선발된 완두자원을 대상으로 완두나물 재배 조건을 설정하기 위하여 <TEX>$20^{\circ}C$</TEX>, <TEX>$23^{\circ}C$</TEX>와 <TEX>$25^{\circ}C$</TEX>에서 각각 7일간 재배하였다. 그 결과 전장과 배축장은 <TEX>$20^{\circ}C$</TEX>와 <TEX>$25^{\circ}C$</TEX>에 비해 <TEX>$23^{\circ}C$</TEX>에서 가장 높게 증가하였다. 3. 재배온도별 나물수율은 <TEX>$23^{\circ}C$</TEX>에서 가장 높게 나타났으며, 유전자원 PI269803와 PI343300이 다른 자원에 비해 높은 나물수율을 나타내었다. 4. 재배온도별 완두나물의 조단백질 함량을 분석한 결과 온도에 따른 조단백질 변화는 나타나지 않았다. 5. 재배 온도별 완두나물의 폴리페놀 함량과 자유 라디칼 소거능을 측정함으로써 항산화 특성을 조사하였다. 그 결과 PI343278와 PI343283에서는 재배 온도가 증가함에 따라 폴리페놀 함량과 자유 라디칼 소거능이 감소하는 경향을 나타내었다. 그러나 PI269803와 PI343300에서는 <TEX>$20^{\circ}C$</TEX>와 <TEX>$25^{\circ}C$</TEX>에 비해 <TEX>$23^{\circ}C$</TEX>에서 높은 폴리페놀 함량과 항산화 활성을 나타내었다. 6. 높은 나물수율과 항산화 특성을 보이는 PI269803과 PI343300은 완두나물 이용에 적합한 자원으로 예상된다. Thirty-eight Pea (Pisum sativum L.) genotypes were screened to identify varieties to be suitable for sprout. Based on seed yield and sprout qualities such as whole length and sprout yield, five genotypes (PI269803, PI343278, PI343283, PI343300 and PI 343307) were primarily selected as candidates for pea sprouts. In order to determine optimal cultivation condition for pea sprouting, growth characteristics were investigated according to the change of germination temperature and days for sprouting. Whole length and hypocotyl length were observed to increase as a time dependent manner at each tested temperature (20, 23, and <TEX>$25^{\circ}C$</TEX>). However, whole length, hypocotyl length, and sprout yield were highly increased at <TEX>$23^{\circ}C$</TEX> compared to 20 and <TEX>$25^{\circ}C$</TEX>. Especially, PI269803 and PI343300 showed higher sprout yield than the others. In addition, the effect of the change of germination temperature on antioxidant properties was estimated by measuring total phenolic content (TPC) and free radical scavenging activity (DPPH and ABST activity). TPC and DPPH/ABST activities of PI269803 and PI343300 were higher at <TEX>$23^{\circ}C$</TEX> than at 20 and <TEX>$25^{\circ}C$</TEX>, while antioxidant properties of PI343278 and PI343283 were decreased in a temperature-dependent manner. The results show a high degree of correlation between TPC and antioxidant activities and suggest that the temperature change for pea sprouting could be responsible for antioxidant properties. Taken together, these results provide optimal cultivation conditions for pea sprouting and suggest that PI269803 and PI343300 with high sprout yield and antioxidant properties could be used for pea sprouts.

Impact of cold atmospheric pressure plasma on physiology and flavonol glycoside profile of peas (Pisum sativum ‘Salamanca’)

Application of plasma is well-established in various industrial processes; its use has also been suggested as an innovative technology in the food sector. Besides the ability to inactivate undesirable microorganisms on heat-sensitive foods, cold atmospheric pressure plasma (CAPP) may also modify and intensify the secondary metabolism in agricultural plant produces along the whole value-added chain. This is because CAPP provides a source of reactive oxygen and nitrogen species and specific UV radiation.The objective of this study was to determine the effects of CAPP treatment on the flavonol glycoside profile of pea seedlings (Pisum sativum ‘Salamanca’), while considering the potential impact on their metabolic activity in different growth stages. Pea seeds, sprouts, and seedlings were exposed to semi-direct CAPP using a dielectric barrier discharge device with air as the process gas. Applying voltages between 6 and 12kVpp at a frequency of 3.0kHz resulted in optical emission spectra dominated by UV-B and UV-C radiation. The specific energy densities were monitored upon varying voltages and treatment times.Exposing swollen pea seeds to plasma (9kVpp) between 1 and 10min increased germination rate and dry matter content but decreased growth rate. Non-acylated and monoacylated triglycosides of quercetin and kaempferol dominated the flavonol glycoside profile, quercetin-3-O-p-coumaroyl-triglucoside being the main flavonoid glycoside. In 15d-old pea seedlings, the concentration of flavonoid glycosides was dose-dependently decreased after two CAPP treatments compared to none or three treatments. Furthermore, photosynthetic efficiency of treated pea sprouts and seedlings declined potentially indicating a negative effect of CAPP treatment on plant metabolism. The responses of pea tissues greatly depended on time point and duration of CAPP treatments. This study represents a first step towards the implementation of the CAPP technology for a targeted modification of valuable secondary plant metabolites during post-harvest chain of agricultural produces.

Effects of sprouting and postharvest storage under cool temperature conditions on starch content and antioxidant capacity of green pea, lentil and young mung bean sprouts

The effects of germination of selected legumes and further storage of sprouts under cool conditions on the phenolics, antioxidant activity and starch content and their potential bioaccessibility were elucidated. In green pea and mung bean sprouts a slight increase of chemically extractable phenolics (including flavonoids) during the first 4days of sprouting was observed. Digestion in vitro released phenolics; however, flavonoids were poorly bioaccessible. Storage of green pea sprouts decreased reducing power and increased the antiradical ability. Reducing potential of potentially bioaccessible fraction of stored lentil sprouts was elevated of 40%, 31% and 23% in 3-, 4- and 5-day-old sprouts, respectively. Postharvest storage significantly increases the starch digestibility and values of expected glycemic index (eGI) – the highest eGIs were determined for 5-day-old stored sprouts; 75.17-green pea, 83.18-lentil and 89.87-mung bean. Bioactivity and nutritional quality of legumes is affected by sprouting and further storage at low temperatures.

Selenium speciation analysis of selenium-enriched food sprouts

In this present study, we prepared selenium-enriched pea and wheat sprouts. During our research we aimed not only to measure the total selenium content of the sprouts but to identify different selenium species.&#x0D; Scientifical researches show why the analytical examination of different selenium (Se) species is necessary: consumption of all kind of Se-species is useful for a person who suffers in selenium deficit, while there is significant difference between effects of different Se-species on person, in whose body the Se-level is just satisfactory. Biological availability, capitalization, accumulation, toxicity of Se-species are different, but the main difference was manifested in the anti-cancer effect of selenium.&#x0D; During our research selenium was used in form of sodium selenite and sodium selenate, the concentration of the solutions used for germination was 10 mg dm-3. Control treatment meant germination in distilled water. Total selenium content of sprout samples was measured after microwave digestion by inductively coupled plasma mass spectrometry (ICP-MS). Different extraction solvents were applied during sample preparation in order to separate different Se-species (0.1 M and 0.2 M HCl or 10 mM citric acid buffer). We wanted the following question to be answered: Which extraction solvent resulted the best extraction efficiency? Selenium speciation analysis of sprout sample extracts was performed by high performance liquid chromatography with anion exchange column, detection of selenium species was performed by ICP-MS.&#x0D; Evaluating our experimental results we have been found that significant amount of selenium of inorganic forms used during germination transformed into organic selenium compounds. There was difference between the amount of Se-species in pea and wheat sprouts and selenium uptake and repartition of selenium species were depended on Se-form used during germination. In addition the chromatogram analysis made us clear as well, that the citric acid solvent proved to be the most effective extraction solvent during sample preparation int he view of organic Se species.

Use of ultrasonication to enhance pea seed germination and microbial quality of pea sprouts

SummaryThis study investigated the effects of ultrasonication, heating and chemical washing on decontamination of seeds of three pea (Pisum sativum) varieties and the microbial safety of their sprouts. Most of the decontamination treatments increased germination, decreased microbial load and enhanced sprout growth. Ultrasonication and NaOCl treatments reduced total aerobic counts on sprouts by 5.86 and 5.51 log units (averages of three varieties), respectively; while other chemical treatments (350 mL L−1 ethanol, 350 mL L−1 vinegar and 10 g L−1 NaCl solutions) failed to reduce total aerobic counts sufficiently enough to secure microbial safety. The ultrasonication not only improved germination (increased from an average of 83 to 97%), but also reduced the total aerobic counts to 2.21 log10 CFU g−1 on seed sprouts. Ultrasonication also increased the sprouts yield to 301.83 g per 10 g seeds. Therefore, ultrasonication can be used as a microbial control treatment for pea sprout production.

Contamination of ready-to-eat raw vegetables with Clostridium difficile in France.

The presence of Clostridium difficile in food like shellfish, vegetables and meat has been reported in several publications during the past few years. The objective of this study was to assess the prevalence of ready-to-eat raw vegetables contaminated with C. difficile in France. One hundred and four ready-to-eat salads and vegetables were studied. Toxigenic C. difficile strains were isolated in three samples (2.9 %): two ready-to-eat salads (one heart of lettuce and one lamb's lettuce salad) and one portion of pea sprouts. The strains belonged to three different PCR ribotypes: 001, 014/020/077 and 015. The detection thresholds for vegetative cells and spores cells varied between 1 and 3 c.f.u. in 20 g salad and between 6 and 15 c.f.u. in 20 g salad, respectively, for the method employed.

Bowman-Birk inhibitor-like protein is secreted by sprouted pea seeds in response to induced colonization by enteropathogenic Escherichia coli.

The interaction between the clinical isolate of enteropathogenic Escherichia coli (EPEC) SBANU8 and pea sprouts was compared with avirulent K 12. E. coli. This was carried out by repeated co-incubation with pea sprouts for 5 days, and the protein profile of the culture supernatant was analyzed by single and two-dimensional electrophoresis. Mass spectrometry analysis led to the identification of two serine protease inhibitors including a Bowman-Birk-type protein secreted by pea sprouts in response to clinical isolate. Expression of the E. coli intimin gene involved in animal host colonization and virulence was studied by reverse transcription polymerase chain reaction. Expression of this gene was high in SBANU8 when co-incubated with pea sprouts. The present study gives baseline data on the molecular level interactions of EPEC and pea sprouts, which are needed to design the outbreak control strategies.

Radiation processing of minimally processed sprouts (dew gram and chick pea): effect on sensory, nutritional and microbiological quality

SummarySprouts have become an important part of the diet because of their nutritive value and low‐calorie content. The effect of radiation processing (1 and 2 kGy dose) on minimally processed dew gram and chick pea sprouts with respect to different quality parameters was studied over a storage period of 16 days at 8 °C. Radiation treatment and storage period did not have any significant effect on the sensory as well as nutritional qualities of irradiated dew gram and chick pea sprout. No significant change (P &gt; 0.05) was observed in the colour and firmness of irradiated sprouts as compared to control samples. However, radiation processing resulted in significant reduction in aerobic plate counts (APC), coliform counts (CC), yeast and mould count (YMC) and staphylococci counts (SC). Radiation processing of dew gram and chick pea sprouts at 1 and 2 kGy extends the shelf life without affecting sensory and nutritional qualities.

Bifunctional cytosolic UDP-glucose 4-epimerases catalyse the interconversion between UDP-D-xylose and UDP-L-arabinose in plants.

UDP-sugars serve as substrates in the synthesis of cell wall polysaccharides and are themselves generated through sequential interconversion reactions from UDP-Glc (UDP-glucose) as the starting substrate in the cytosol and the Golgi apparatus. For the present study, a soluble enzyme with UDP-Xyl (UDP-xylose) 4-epimerase activity was purified approx. 300-fold from pea (Pisum sativum L.) sprouts by conventional chromatography. The N-terminal amino acid sequence of the enzyme revealed that it is encoded by a predicted UDP-Glc 4-epimerase gene, PsUGE1, and is distinct from the UDP-Xyl 4-epimerase localized in the Golgi apparatus. rPsUGE1 (recombinant P. sativum UGE1) expressed in Escherichia coli exhibited both UDP-Xyl 4-epimerase and UDP-Glc 4-epimerase activities with apparent Km values of 0.31, 0.29, 0.16 and 0.15 mM for UDP-Glc, UDP-Gal (UDP-galactose), UDP-Ara (UDP-L-arabinose) and UDP-Xyl respectively. The apparent equilibrium constant for UDP-Ara formation from UDP-Xyl was 0.89, whereas that for UDP-Gal formation from UDP-Glc was 0.24. Phylogenetic analysis revealed that PsUGE1 forms a group with Arabidopsis UDP-Glc 4-epimerases, AtUGE1 and AtUGE3, apart from a group including AtUGE2, AtUGE4 and AtUGE5. Similar to rPsUGE1, recombinant AtUGE1 and AtUGE3 expressed in E. coli showed high UDP-Xyl 4-epimerase activity in addition to their UDP-Glc 4-epimerase activity. Our results suggest that PsUGE1 and its close homologues catalyse the interconversion between UDP-Xyl and UDP-Ara as the last step in the cytosolic de novo pathway for UDP-Ara generation. Alternatively, the net flux of metabolites may be from UDP-Ara to UDP-Xyl as part of the salvage pathway for Ara.

HEALTH-RELATED FUNCTIONALITY OF PHENOLIC-ENRICHED PEA SPROUTS IN RELATION TO DIABETES AND HYPERTENSION MANAGEMENT

ABSTRACT The rationale for this investigation is that phenolic content in light-modulated pea seedlings could be enhanced by exogenous elicitors with antioxidant potential such as folic acid and vitamin C. Such phenolic-enriched extracts may have health benefits to consumers. The antioxidant-linked functional attributes of the phenolic-enriched extracts were evaluated for potential health-related benefits. Specifically, effectiveness in inhibiting α-amylase and α-glucosidase in relation to hyperglycemia (linked to diabetes management), as well as inhibiting angiotensin-converting enzyme I (ACE I), in relation to hypertension, was evaluated. The results show that phenolic-enriched extracts had the ability to inhibit α-amylase and α-glucosidase activity. On the day with the highest total phenolic content, day 8, inhibition of α-amylase and α-glucosidase was most prominent. Further, the same extracts showed positive benefits for potential hypertension management reflected in the inhibition of ACE I. These results taken together indicated that light-sprouted pea seedling extracts when incorporated into the diet could contribute to potential management of hyperglycemia linked to diabetes and hypertension related to cardiovascular risk. PRACTICAL APPLICATIONS In this in vitro study results show the positive effect of the different phenolic-enriched pea sprouts on hyperglycemia risk factors. It is clear that phenolic-enriched pea sprouts have high antioxidant activity, ACE 1 inhibitory activity and also good inhibitory activity on carbohydrate-modulating enzyme such as alpha-glucosidase related to glucose absorption in the intestine. The potential for managing both glucose absorption and cellular redox dysfunction for preventing postprandial hyperglycemia linked to type 2 diabetes and hyperglycemia-induced vascular complications leading to hypertension can be designed in part through food systems and therefore provides the rationale basis for further clinical studies. This strategy can be further extended to enhance phenolic-linked health benefits of a wide variety of legumes, fruits and vegetables and therefore can be the basis for food ingredient design for functional food applications.

THE EFFECTS OF GERMINATION ON THE SENSORY QUALITY AND IMMUNOREACTIVE PROPERTIES OF PEA (PISUM SATIVUM L.) AND SOYBEAN (GLYCINE MAX)

ABSTRACT The seeds of pea and soybean were germinated with and without light at 20C up to 3 days. After germination, fresh sprouts were subjected to sensory evaluation using quantitative descriptive analysis and hedonic tests. Changes in the immunoreactivity of the samples were determined by competitive enzyme‐linked immunoabsorbent assay using rabbit polyclonal antisera to pea and soybean proteins. The results indicated that the sensory quality of pea sprouts was significantly better than that of soybean. The dominating attributes differentiating the soybean samples from the pea samples were rancid odor and taste, which had clearly negative effect on their overall quality. The immunoreactive properties of the samples were dependent on whether they were with or without cotyledons. Removal of the cotyledons almost completely reduced the immunoreactivity of soybean and pea. The presence or absence of light during the germination process did not affect the results. PRACTICAL APPLICATIONSThe results indicated that the germination of pea and soybean seeds is a relevant processing technique for reducing their immunoreactivity. This suggests that pea and soybean sprouts could be used to develop the special products for people who suffer from food allergic disorders. Further studies in this field should be carried out to determine whether it is possible to reduce the total immunoreactivity of pea and soybean seeds by prolonging their germination time. From the sensory viewpoint, pea sprouts appear to have an advantage over soybean sprouts in food system applications. The substantial reasons for the limited use of soybean sprouts arise from their rancid odor and taste.

Assessment of protein fractions of three cultivars of Pisum sativum L.: effect of germination

Protein composition, nitrogen and amino acid content of Osborne fractions in different cultivars of Pisum sativum L. (cv. ucero, cv. ramrod and cv. agra) seeds were investigated and the effect of germination on these parameters was also analysed. Albumins comprised the main protein fraction in raw seeds, globulins were constituted mainly by vicilin, with a smaller proportion of the glutelin and prolamine fractions. Regarding the amino acid profile of pea protein fractions, although differences among pea cultivars were found, in general albumin, glutelin and prolamine fractions presented Asp, Glu and Gly as the major non-essential amino acids (NEAA) and Lys as the main essential amino acid (EAA). The globulin fraction, however, presented Asp, Glu, Gly and Arg as the major NEAA and Leu, Phe, Lys, and Thr as the main EAA. In general, the albumin fraction accounted for more sulphur amino acids and Lys, followed by the glutelin + prolamine fraction. Germination caused an increase in the total protein content of P. sativum cv. ucero and P. sativum cv. ramrod. In the albumin fraction a wide number of proteins underwent degradation and convicilin disappeared from the globulin fraction of pea sprouts whilst vicilin and legumin decreased slightly. In general, all the Osborne fractions of pea sprouts presented higher EAA contents than raw seeds. The estimated essential amino acid indexes of protein fractions for P. sativum cv. ucero (EAAIadult and EAAIegg) improved with the germination process whilst for P. sativum cv. ramrod and P. sativum cv. agra depended on the Osborne fraction.

Effect of radiation processing on nutritional and sensory quality of minimally processed green gram and garden pea sprouts

In the present study, radiation processing of minimally processed green gram and garden pea sprouts was carried out at doses 1 and 2 kGy. The effect of this treatment on different quality parameters like vitamin C content, total carotenoids content, sensory quality, texture, and color was determined over a storage period of 12 days at two different temperatures, a 4 and 8 °C. It was observed that treatment of irradiation (1 and 2 kGy) and storage period did not have any significant effect on vitamin C content of control as well as irradiated sprout samples stored at 4 and 8 °C. Total carotenoids content of sprouts stored at 4, as well as at 8 °C, for 12 days remained almost unchanged after irradiation as well as during storage. Sensory evaluation studies showed that irradiation had no significant effect ( p>0.05) on the ratings of any of the sensory attributes in green gram as well as garden pea sprouts and, thus, did not alter the overall acceptability of the irradiated sprouts. Textural studies revealed that there was no significant change ( p>0.05) in the firmness of irradiated sprouts (1 and 2 kGy) as compared to control samples at both the temperatures. Storage period of 12 days also did not affect the firmness of sprouts significantly. Color measurement results indicated no drastic change in the color coordinates of the green gram samples except greenness of controls stored at both the temperatures, which showed insignificant decrease in the a * values. Thus, the nutritional as well as sensory quality of minimally processed green gram and garden pea sprouts did not alter significantly after gamma irradiation with a dose of 1 and 2 kGy.

Evaluation of zinc and magnesium bioavailability from pea (Pisum sativum, L.) sprouts. Effect of illumination and different germination periods

SummaryThe effect of sprouting pea seeds (Pisum sativum, L) for 2, 4 and 6 days, with and without light, on the content of zinc (Zn) and magnesium (Mg) and their nutritive utilisation by growing rats was studied. Soaking of pea seeds prior to germination caused a 49% reduction in Zn content followed by minor losses during germination. The content of Mg decreased by 6% as a result of the soaking process, and by 20–28% during germination. Sprouting for 2 and 4 days improved the bioavailability of Zn and Mg from pea seeds (from 32.2 to 88.6–108.0 μg retained Zn per day, and from 1.64 to 2.97–4.79 mg retained Mg per day in raw and sprouted pea flour diets, respectively), outweighing the reductions in Zn and Mg content because of seed soaking. The presence or absence of light during the germination process did not affect the results. We conclude that sprouting of peas for 4 days was the most effective treatment to improve the bioavailability of Zn and Mg in pea seeds.

INHIBITION OF HELICOBACTER PYLORI BY PHENOLIC EXTRACTS OF SPROUTED PEAS (PISUM SATIVUM L.)

Infection by Helicobacter pylori is associated with gastric and duodenal ulcers. Conventional treatments to eradicate it have side-effects such as diarrhea and dizziness. The excessive use of antibiotics could also lead to antibiotic-resistant bacteria. The use of plant phenolic phytochemicals can be an alternative because of their health benefits due to both antioxidant activity and antimicrobial activity. The pea (Pisum sativum), the world's second most important pulse crop, produces phenolic phytochemicals with antimicrobial potential. Because the synthesis of phenolic compounds increases with stress, we investigated the anti-H. pylori effectiveness of extracts from pea sprouts, germinated in the dark condition following treatment with either distilled water or acetyl salicylic acid. The peas were germinated for 8 days and the sprouted samples were measured for total soluble phenolic content, antioxidant and guaiacol peroxidase activity. Subsequently, the sprout extracts were tested for anti-H. pylori activity using the agar diffusion method and the effective dose was determined based on phenolic content. The results showed that both acetyl salicylic acid-treated and untreated pea sprouts at days 5 and 8 had anti-H. pylori activity. The minimum volume for inhibition was 50 μL of extracts. The inhibitory effects were dose dependent. From this study, the potential to use natural phenolic phytochemicals from pea sprouts to control H. pylori was found to be promising. This provides a strategy and foundation to design legume phenolics as functional ingredients against H. pylori.

糖1-リン酸に幅広い基質特性性を有する新規のUDP-糖ピロフォスフォリラーゼ

糖1-リン酸に幅広い基質特性性を有する新規のUDP-糖ピロフォスフォリラーゼ

UDP-sugar Pyrophosphorylase with Broad Substrate Specificity Toward Various Monosaccharide 1-Phosphates from Pea Sprouts

UDP-sugars, activated forms of monosaccharides, are synthesized through de novo and salvage pathways and serve as substrates for the synthesis of polysaccharides, glycolipids, and glycoproteins in higher plants. A UDP-sugar pyrophosphorylase, designated PsUSP, was purified about 1,200-fold from pea (Pisum sativum L.) sprouts by conventional chromatography. The apparent molecular mass of the purified PsUSP was 67,000 Da. The enzyme catalyzed the formation of UDP-Glc, UDP-Gal, UDP-glucuronic acid, UDP-l-arabinose, and UDP-xylose from respective monosaccharide 1-phosphates in the presence of UTP as a co-substrate, indicating that the enzyme has broad substrate specificity toward monosaccharide 1-phosphates. Maximum activity of the enzyme occurred at pH 6.5-7.5, and at 45 degrees C in the presence of 2 mm Mg(2+). The apparent K(m) values for Glc 1-phosphate and l-arabinose 1-phosphate were 0.34 and 0.96 mm, respectively. PsUSP cDNA was cloned by reverse transcriptase-PCR. PsUSP appears to encode a protein with a molecular mass of 66,040 Da (600 amino acids) and possesses a uridine-binding site, which has also been found in a human UDP-N-acetylhexosamine pyrophosphorylase. Phylogenetic analysis revealed that PsUSP can be categorized in a group together with homologues from Arabidopsis and rice, which is distinct from the UDP-Glc and UDP-N-acetylhexosamine pyrophosphorylase groups. Recombinant PsUSP expressed in Escherichia coli catalyzed the formation of UDP-sugars from monosaccharide 1-phosphates and UTP with efficiency similar to that of the native enzyme. These results indicate that the enzyme is a novel type of UDP-sugar pyrophosphorylase, which catalyzes the formation of various UDP-sugars at the end of salvage pathways in higher plants.