Effect Of Germination Conditions Research Articles

Effects of germination conditions on enzyme activities and starch hydrolysis of long-grain brown rice in relation to flour properties and bread qualities.

Gluten-free products from rice are gaining popularity because of its hypoallergenic characteristic. The absence of gluten results in inferior bread qualities such as hard texture, reduced volume, and shorter shelf-life. Hydrolytic enzymes are activated during germination to stimulate plant growth, and germinated brown rice (GBR) has been shown to improve gluten-free bread properties. However, the changes in hydrolytic enzyme activities under different germination conditions and their relationship with the properties of germinated rice flour and bread have not been reported. Therefore, the objectives of this work were to investigate the activities of amylases and protease in GBR under aerobic and anaerobic germination for 2 and 4 days and their impacts on starch hydrolysis, flour properties, and bread qualities. Greater enzyme activities were observed in GBR germinated under aerobic condition and a longer time, and correlated with increased sugar content and foaming capacity. Breads were prepared from GBR along with brown rice (control). GBR breads showed a greater specific volume (4% to 10%), a reduced hardness (34% to 90%), and a lower starch retrogradation (66% to 90%) compared with the control. Bread prepared from 4-day aerobic GBR had the largest reduction in starch molecular size and displayed the lowest hardness and starch retrogradation. After stored for 5 days, GBR breads exhibited no change in specific volume and less hardness and retrogradation than the control bread. In conclusion, greater activities of protease and amylases in GBR significantly increased foaming capacity and reduced starch molecule size, respectively, which were responsible for the improved GBR bread qualities. PRACTICAL APPLICATION: Rice flour is widely used as the main ingredient in gluten-free breads, which however tend to have poor texture and reduced shelf-life due to the absence of gluten. The qualities of gluten-free breads are usually improved by the addition of many ingredients such as tapioca and potato starches. Germination process naturally produces bioactive compounds and activates enzymes. Germination conditions that produce greater activities of amylases and protease can be used to produce gluten-free breads with better qualities and longer shelf-life without the addition of starch.

Effect of Germination Conditions and Mashing Temperature on the Amylolytic Enzyme Activity and Degree of Starch Saccharification of Brown Rice Cultivars During Syrup Production.

The germination process activates amylolytic enzymes that can produce rice syrup through mashing, however the factors affecting enzyme activities and soluble saccharides have not been investigated. This study characterized amylolytic enzymes activities, including α-amylase, β-amylase, and α-glucosidase, and soluble saccharides from germinated rice cultivars of four rice cultivars, including waxy, short grain, medium grain, and long grain, under aerobic and anaerobic germination conditions over 4 days and then mashed at 55, 65, 75, and 85 °C. The results showed that the long-grain rice had higher activities of all three enzymes, whereas the waxy rice exhibited lower activities. Glucose and maltose were the predominant saccharides at low mashing temperatures of 55 °C and 65 °C; saccharides of degree of polymerization 3 to 7 became significant at mashing temperatures of 75 °C and 85 °C. The amount and composition of saccharides were strongly influenced by rice cultivar, and germination and mashing conditions. The findings highlight the importance of rice components and starch structure on the amount and composition of soluble saccharides from germinated brown rice. PRACTICAL APPLICATION: Rice syrup is commercially produced by the addition of external bacterial enzymes to brown or milled rice. Germinated brown rice is naturally rich in nutrients and amylases, both are produced during the germination process. Because of the presence of naturally activated amylases, germinated brown rice could be used to produce rice syrup without the addition of external enzymes while preserving the nutrients from germination of brown rice.

Effects of germination conditions on peptides accumulation in soybean (Glycine max L. Merr.)

High levels of peptides can accumulate in tissues of legumes during germination. In this study, effects of germination conditions (pH, temperature, and time) on protease activity and peptides accumulation in soybean were investigated. The desirable level scope of parameters was used to further optimise germination conditions for peptides accumulation using response surface methodology. Results showed that protease activity and peptides yield were significantly influenced by pH, temperature, and time (P<0.05). The optimal pH, temperature, and time for protease activity were 5, 25 °C, and 6 days, respectively. Meanwhile, the optimal pH, temperature, and time for peptides content were 5, 30 °C, and 5 days, respectively. Box–Behnken design indicated the following optimal germination conditions: pH 4.8, temperature 29 °C, and time 5 days. Under these conditions, the highest peptides content (14.46 mg g–1 FW) in germinated soybean was obtained. The present study indicates that germinated soybean can be a valuable component of peptides-enriched foods.

Effects of germination on the nutritive value and bioactive compounds of brown rice breads

The effect of germination conditions on the nutritional benefits of germinated brown rice flour (GBR) bread has been determined. The proximate composition, phytic acid, in vitro protein digestibility and in vitro enzymatic hydrolysis of starch, glucose and starch content, as well as the most relevant bioactive compounds (GABA, γ-oryzanol and total phenolic compounds) and antioxidant activity of breads prepared with GBR at different germination conditions was determined. When comparing different germination times (0h, 12h, 24h and 48h), germination for 48h provides GBR bread with nutritionally superior quality on the basis of its higher content of protein, lipids and bioactive compounds (GABA and polyphenols), increased antioxidant activity and reduced phytic acid content and glycaemic index, although a slight decrease in in vitro protein digestibility was detected. Overall, germination seems to be a natural and sustainable way to improving the nutritional quality of gluten-free rice breads.

Effect of Germination and Thermal Treatments on Folates in Rye

Effects of germination conditions and thermal processes on folate contents of rye were investigated. Total folate contents were determined microbiologically with Lactobacillus rhamnosus (ATCC 7469) as the growth indicator organism, and individual folates were determined by high-performance liquid chromatography after affinity chromatographic purification. Germination increased the folate content by 1.7-3.8-fold, depending on germination temperature, with a maximum content of 250 micro g/100 g dry matter. Hypocotylar roots with their notably high folate concentrations (600-1180 micro g/100 g dry matter) contributed 30-50% of the folate contents of germinated grains. Germination altered the proportions of folates, increasing the proportion of 5-methyltetrahydrofolate and decreasing the proportion of formylated folate compounds. Thermal treatments (extrusion, autoclaving and puffing, and IR and toasting) resulted in significant folate losses. However, folate levels in grains that were germinated and then were heat processed were higher than for native (nongerminated) grains. Opportunities to optimize rye processing to enhance folate levels in rye-based foods are discussed.

Factors affecting germination of jointed goatgrass (Aegilops cylindrica) seed

Specific knowledge about the dormancy, germination, and emergence patterns of weed species aids the development of integrated management strategies. The after-ripening period for jointed goatgrass seed was quantified, and the effects of germination conditions and spikelet structures on jointed goatgrass seed germination were measured. As the duration of after-ripening increased, jointed goatgrass seed germinated earlier, at faster rates, and to greater final percentages compared to non–after-ripened seed. Both primary and secondary positioned seed within jointed goatgrass spikelets were nondormant after 16 wk after-ripening at 22 ± 2 C. Germination of dormant seed depended on incubation temperature and dark/light conditions. Sixty-seven percent of spikelets produced a radicle when exposed to low temperatures in the dark, and light at warm temperatures increased germination by 7%. The relationship between light and incubation temperature was similar also for germination of the primary positioned seed in nondormant spikelets; however, the magnitude of the effect increased. Light increased germination of seed incubated at warm temperatures by 18%. Coleoptile emergence was dependent on planting depth for three jointed goatgrass populations, winter wheat, and spring wheat. Under optimum conditions in the greenhouse, no planting depth selectively allowed wheat germination and emergence while preventing jointed goatgrass germination and emergence. Glume removal increased jointed goatgrass secondary positioned seed final germination percentage to 96%, increased the germination rate, and decreased the number of days required to reach 50% germination to 6 d. Glume removal also promoted germination of the primary seed within jointed goatgrass spikelets. Glume removal resulted in 80% of the spikelets having two coleoptiles, but did not alleviate dormancy completely in jointed goatgrass seed. Tillage and herbicide applications for jointed goatgrass control will be most effective in the fall when primary dormancy is lost, but before secondary dormancy is imposed.

Assessing the benefits of frugivory for seed germination: the importance of the deinhibition effect

Summary Many studies have examined the effects of frugivores on the germination of seeds of fleshy fruited plants. However, three key issues are rarely addressed: the need to measure germination of seeds in intact fruits; the effect of germination conditions on results; and the distinction between dead vs dormant seeds. A literature review including 51 plant species from 28 families found that the often‐measured scarification effect (germination of bird‐defecated vs hand‐cleaned seeds) is significantly smaller than the rarely‐measured deinhibition effect (germination of hand‐cleaned seeds vs those in intact fruits). Both the literature review and new experimental data show that germination conditions affect germination. In particular, seeds in intact fruits have much lower germination percentages in Petri dishes than in the field. Poor germination from intact fruits in Petri dishes may be an artefact. A field experiment with three New Zealand species showed variable effects of non‐removal of the fruit pericarp. The retention of the pericarp had no effect on germination in Nestegis cunninghamii; increased the proportion of seeds entering dormancy in Melicytus lanceolatus; and greatly increased seed mortality in Pennantia corymbosa. Germination experiments must be designed carefully to evaluate accurately the risks for plants of frugivory mutualism failures.

Effects of germination conditions on ascorbic acid level and yield of soybean sprouts

AbstractThe effects of light illumination on the ascorbic acid content and growth of soybean sprouts were investigated. Among the six light qualities studied, ultraviolet light had the highest promoting effect on the ascorbic acid content in soybean sprouts, increasing it by 77.0% compared with the darkness control, while red light had the highest promoting effect on the growth of soybean sprouts, increasing the total fresh weight by 16.6% compared with the darkness control. Experiments with different durations of ultraviolet and red light illumination in a day showed that 12 h ultraviolet (500 Lx) and 12 h red (1000 Lx) light diurnal cycles had the highest promoting effects on both the ascorbic acid level and fresh weight of soybean sprouts, increasing the ascorbic acid content and total fresh weight by 78.7 and 17.4% respectively compared with the darkness control. The results indicated that germination of soybeans under 12 h ultraviolet and 12 h red light diurnal cycles was an effective process for increasing the yield and enhancing the nutritional quality of soybean sprouts. Copyright © 2005 Society of Chemical Industry

Influence of germination on lectin in Lens culinaris seeds

The effect of germination conditions on the lectin of Lens culinaris var. Magda 20 seeds was studied. The seeds were germinated at 20 °C under different conditions of watering and light and for different periods of time. The seed lectin was assayed by haemagglutination and quantified by competitive ELISA. Changes in lectin content during germination were also monitored by SDS-PAGE and immunoblotting. Haemagglutinating activity and lectin content in the seeds were not changed during the first three days regardless of the conditions of the germination. However, lectin concentration was significantly higher after six days of germination; relative lectin levels being particularly high when germination was carried out in the light and with daily watering. The results of SDS-PAGE and immunoblotting have also shown that the lectin was not degraded during the first six days of germination however, other storage-proteins were broken down by proteolysis.

Direct sowing of Coffea arabica somatic embryos mass-produced in a bioreactor and regeneration of plants.

The effect of germination conditions on the morphology of Coffea arabica L. somatic embryos mass-produced in a 1-l temporary immersion bioreactor (RITA®) was studied with emphasis on direct sowing in soil. Using germinated embryos, direct sowing resulted in a highly successful conversion of embryos into plants. A culture density above 1600 embryos per 1-l bioreactor positively affected embryo morphology by causing higher embryonic axis elongation (+4-5 mm). At this density, the addition of a high concentration of sucrose (234 mM) 2 weeks before sowing promoted an increase in effective plant conversion in soil (78%) and a vigorous vegetative growth of the resulting plants. Furthermore, direct sowing reduced handling time to 13% and shelving area requirements to 6.3% of the values obtained by conventional acclimatization of plants developed on gel media.

Effect of Germination, under Different Environmental Conditions, on Saponins, Phytic Acid and Tannins in Lentils (Lens culinaris)

The effect of germination conditions on some antinutrients of Lens culinaris var Magda 20 seeds were studied. The seeds were germinated at 20°C under variable conditions of time, water and light. Quantitative analyses of the soyasapogenols, inositol phosphates and tannins were carried out by capillary gas chromatography, high-performance liquid chromatography and spectrophotometric techniques respectively. Germinated seeds at day 6 contained higher levels soyasapogenol B than the controls, whereas in general the tannin content was reduced. Total phytic acid amounts did not decrease after 3 days of germination but was greatly reduced after 6 days. This work shows that the optimal conditions to reduce some antinutritional factors (tannins and phytic acid) in lentils were 6 days of seed germination in dark and with alternate watering. Therefore, germination conditions offer a good opportunity to improve the nutritional quality of lentils. © 1997 SCI.

Effect of Germination, under Different Environmental Conditions, on Saponins, Phytic Acid and Tannins in Lentils (Lens culinaris)

The effect of germination conditions on some antinutrients of Lens culinaris var Magda 20 seeds were studied. The seeds were germinated at 20°C under variable conditions of time, water and light. Quantitative analyses of the soyasapogenols, inositol phosphates and tannins were carried out by capillary gas chromatography, high-performance liquid chromatography and spectrophotometric techniques respectively. Germinated seeds at day 6 contained higher levels soyasapogenol B than the controls, whereas in general the tannin content was reduced. Total phytic acid amounts did not decrease after 3 days of germination but was greatly reduced after 6 days. This work shows that the optimal conditions to reduce some antinutritional factors (tannins and phytic acid) in lentils were 6 days of seed germination in dark and with alternate watering. Therefore, germination conditions offer a good opportunity to improve the nutritional quality of lentils. © 1997 SCI.

EFFECT OF GERMINATION TIME, TEMPERATURE AND MOISTURE ON MALTING OF SORGHUM

The effect of germination conditions on sorghum malt quality and malting loss was studied by germinating sorghum for different periods of time up to 6 days over a range of temperatures (24 to approximately 36°C) and moisture conditions. The moisture conditions varied from that sufficient to maintain green malt weight to that where surface moisture remained on the malt throughout germination. Germination time, temperature, moisture and the three possible pairwise interactions all had a highly significant effect on malt diastatic power, free α-amino nitrogen and extract. Malting loss was highly significantly affected by germination time and moisture and their pair-wise interaction. However, over the range examined, germination temperature had no significant effect on malting loss. In general diastatic power, free α-amino nitrogen, extract, and malting loss all increased with germination time. Germination temperatures of 24° and 28°C were both equally good for the development of diastatic power, free α-amino nitrogen and extract but higher temperatures were progressively worse. Distatic power, free α-amino nitrogen, extract and malting loss were, in general, all increased by high moisture during germination. However, high moisture and a negative effect on diastatic power towards the end of the germination period.