Bioavailability of zinc from cooked philippine milled,undermilled, and brown rice,as assessed in rats by using growth,bone zinc,and zinc-65 retention

The nutritional bioavailability of zinc from cooked milled, undermilled, and brown Philippine rice (variety PSB Rc14) was evaluated in rats, comparing results based on weight gain, tibia zinc incorporation (slope ratio analyses), and zinc radiotracer retention. Milling reduced the phytic acid and mineral content of the rice, resulting in zinc concentrations of 16.5, 19.4, and 27.2 microg/g and phytate/zinc molar ratios of 4, 20, and 28 for milled, undermilled, and brown rice, respectively. Measured zinc bioavailability was similar whether using growth, bone zinc, or radioisotope retention as criteria, at approximately 92, 86, and 77% of zinc sulfate, for milled, undermilled, and brown rice, respectively. However, the higher percent bioavailability of the zinc after milling was insufficient to compensate for the lower zinc content. With respect to zinc, the nutritional value was inversely related to milling, providing approximately 15, 17, and 21 microg bioavailable zinc/g rice, respectively, for milled, undermilled and brown rice of this variety.     

Effect of different foliar zinc application at different growth stages on seed zinc concentration and its impact on seedling vigor in rice

This study evaluated how zinc (Zn) concentration of rice (Oryza sativa L.) seed may be increased and subsequent seedling growth improved by foliar Zn application. Eight foliar Zn treatments of 0.5% zinc sulfate (ZnSO₄?·?7H₂O) were applied to the rice plant at different growth stages. The resulting seeds were germinated to evaluate effects of seed Zn on seedling growth. Foliar Zn increased paddy Zn concentration only when applied after flowering, with larger increases when applications were repeated. The largest increases of up to ten-fold were in the husk, and smaller increases in brown rice Zn. In the first few days of germination, seedlings from seeds with 42 to 67?mg Zn?kg^?1 had longer roots and coleoptiles than those from seeds with 18?mg Zn?kg^?1, but this effect disappeared later. The benefit of high seed Zn in seedling growth is also indicated by a positive correlation between Zn concentration in germinating seeds and the combined roots and shoot dry weight (r?=?0.55, p?相似文献   

Impact of Feedstock,Parboiling Condition,and Nutrient Concentration on Simultaneous Fortification of Two U.S. Long‐Grain Rice Cultivars with Iron and Zinc

This work investigated the effect of parboiling on simultaneous fortification of rice with iron (Fe) and zinc (Zn) using rough rice and brown rice as feedstocks. Three fortificant concentrations (0, 100, and 200 mg/L for both Fe and Zn) were tested, and two long‐grain rice cultivars (CLXL745 and RoyJ) were used as test samples. Cultivar had little impact on the retention of Fe and Zn; steaming combined with soaking significantly increased the migration of Fe and Zn into the endosperm compared with soaking only. The Fe and Zn contents of the resultant parboiled head rice were related to the initial concentrations in the soaking water and were 7.2–17.6 and 21.8–31.9 mg/kg, respectively, when rough rice was used as a feedstock, and they significantly increased to 32.4–84.9 mg/kg for Fe and 45.8–78.4 mg/kg for Zn when brown rice was used as a feedstock. Mineral retention after simulated washing was 87.5–95.1% for Fe and 81.1–84.3% for Zn. Dilute‐HCl extractability as an indicator of mineral bioavailability was 66.2–72.4% for Fe and 83.4–92.0% for Zn. The results indicate that brown rice is a better feedstock than rough rice for mineral fortification via parboiling.     

拔节期土壤施锌对小麦籽粒中锌生物有效性影响评估

本研究通过2012—2013及2013—2014两个年度的田间试验,在小麦(扬麦-16)的拔节期土壤施加高用量的锌肥,通过植酸/锌摩尔比法,对小麦籽粒进行了锌生物有效性评价,每公顷施ZnSO4·7H2O的量达到300 kg能显著提高小麦籽粒锌含量,小麦籽粒锌含量达到60 mg/kg以上,小麦籽粒植酸/锌摩尔比显著降低,植酸/锌摩尔比最大可降低至15以下,表明小麦锌强化后籽粒中锌的生物有效性得到显著提高。     

Analysis of phenolic compounds in white rice, brown rice, and germinated brown rice

Two hydroxycinnamate sucrose esters, 6'-O-(E)-feruloylsucrose and 6'-O-(E)-sinapoylsucrose, were isolated from methanol extracts of rice bran. Soluble and insoluble phenolic compounds as well as 6'-O-(E)-feruloylsucrose and 6'-O-(E)-sinapoylsucrose from white rice, brown rice, and germinated brown rice were analyzed using HPLC. The results demonstrated that the content of insoluble phenolic compounds was significantly higher than that of soluble phenolics in rice, whereas almost all compounds identified in germinated brown rice and brown rice were more abundant than those in white rice. 6'-O-(E)-Feruloylsucrose (1.09 mg/100 g of flour) and 6'-O-(E)-sinapoylsucrose (0.41 mg/100 g of flour) were found to be the major soluble phenolic compounds in brown rice. During germination, an approximately 70% decrease was observed in the content of the two hydroxycinnamate sucrose esters, whereas free phenolic acid content increased significantly; the ferulic acid content of brown rice (0.32 mg/100 g of flour) increased to 0.48 mg/100 g of flour and became the most abundant phenolic compound in germinated brown rice. The content of sinapinic acid increased to 0.21 mg/100 g of flour, which is nearly 10 times as much as that in brown rice (0.02 mg/100 g of flour). In addition, the total content of insoluble phenolic compounds increased from 18.47 mg/100 g of flour in brown rice to 24.78 mg/100 g of flour in germinated brown rice. These data suggest that appropriate germination of brown rice may be a method to improve health-related benefits.     

Effect of Parboiling on Milling,Physicochemical, and Textural Properties of Medium‐ and Long‐Grain Germinated Brown Rice

Germinated brown rice is considered a more nutritious and palatable cooked product than conventional brown rice. However, germination usually decreases rice milling yield and alters some physicochemical properties. Parboiling is commonly used to increase milling yield and retain nutrients, but it also changes rice color and texture. The objective of this study was to investigate the effect of parboiling on milling, physicochemical, and textural properties of a medium‐grain and a long‐grain rice after germination at varying durations. Germinated rice samples of three germination durations were prepared with one germination time before the optimum time at which 70% of rice revealed hull protrusion, the optimum time, and one time after. Germinated rice was then immediately parboiled at 120°C for 20 min and was then immediately dried. The milling, physicochemical, and textural properties of parboiled germinated rice from both cultivars were determined. Parboiling significantly decreased the percentage of brokens, whiteness, and the apparent amylose content and increased γ‐aminobutyric acid content (GABA) in the nongerminated rice and rice at the first germination duration for both cultivars. Parboiling reduced pasting viscosities for both cultivars, but Jupiter still exhibited higher pasting viscosities than Wells. Cooked parboiled germinated rice was overall softer than nonparboiled rice because of kernel splitting, but Wells remained harder and less sticky than Jupiter. In conclusion, it is beneficial to combine parboiling with germination to enhance nutritional values and improve milling properties without affecting textural properties for both rice cultivars.     

土施和喷施锌肥对冬小麦子粒锌含量及生物有效性的影响

为揭示潜在性缺锌土壤上不同施锌方式对小麦子粒锌含量及其生物有效性的影响,选用5个冬小麦品种进行了土施和喷施锌肥的田间裂区试验。结果表明,供试土壤条件下,不同施锌方式对小麦产量均无明显影响,但是在一定施锌方式下小麦子粒锌含量大幅度提高。与对照相比,土施、喷施及土施+喷施锌肥提高小麦子粒锌含量幅度分别为-6.1%、64%和83%,提高小麦子粒锌携出量幅度分别为-3.6%、69%和83%。3个施锌处理降低子粒中植酸含量的幅度分别为-2.4%、7.2%和1.5%,降低植酸与锌摩尔比的幅度分别为-25%、41%和44%,且不同品种之间也存在一定差异;虽然植酸与锌的摩尔比有所下降,但仍高于20。此外,单独土施锌肥虽可大幅度提高耕层土壤有效锌含量,但对子粒锌含量及生物有效性的影响很小。总之,在小麦生长后期喷施锌肥是提高潜在性缺锌土壤上小麦子粒锌含量和生物有效性较为经济的方式,对改善小麦锌营养品质有较好作用。     

Fortification of milk with calcium: effect on calcium bioavailability and interactions with iron and zinc

Calcium solubility, dialysability, and transport and uptake (retention + transport) by Caco-2 cells as indicators of calcium bioavailability have been estimated in the in vitro gastrointestinal digests of milk and calcium fortified milk. A significant linear correlation (p < 0.05) was obtained between calcium uptake and the amount of soluble calcium added to the cells, and also between percentage calcium uptake and the calcium measured in the analyzed samples. The solubility, dialysis, transport, and uptake values are higher (p < 0.05) for calcium fortified milks than for nonfortified milks; that is, calcium fortification increases not only calcium content but also its bioavailability. An inhibitory effect of calcium from fortified milks upon iron absorption was found. The observed effect of calcium from fortified milks upon zinc bioavailability depends on the in vitro method used, zinc solubility and dialysis decrease in calcium fortified milks, and percentage zinc uptake remains unchanged.     

不同品种水稻糙米对Cd Cu Zn积累特性的研究

以酸性矿山废水污染的含有多种重金属的农田土壤为供试土壤,通过盆栽实验,研究不同水稻品种,不同类型、不同遗传背景水稻糙米重金属Cd、Cu、Zn的积累差异。结果表明,供试水稻糙米Cd含量为0.006～0.092mg·kg-1,最高值和最低值相差15倍;Cu含量为6.712～27.117mg·kg-1,最高值和最低值相差4倍;Zn含量为28.390～43.296mg·kg-1,最高值和最低值相差不到1倍。常规稻和杂交稻糙米的Cd、Cu、Zn含量差异不明显。三系杂交稻的糙米Cd、Cu含量极显著高于二系杂交稻,而二系杂交稻糙米中Zn含量则显著高于三系杂交稻。不同遗传背景水稻品种糙米Cd、Cu、Zn含量也存在明显差异。相关分析结果表明,糙米中Cu、Cd含量间呈极显著正相关,Cu、Zn含量之间存在显著负相关,而Cd、Zn含量间的相关性不明显。     

Effects of Germination Duration on Milling,Physicochemical, and Textural Properties of Medium‐ and Long‐Grain Rice

Germinated brown rice is popular in Asia for its increased γ‐aminobutyric acid (GABA) content and sweeter and softer texture compared with conventional brown rice. However, most studies investigated germinated rice properties on medium‐grain or aromatic rice. The objective of this study was to compare differences between a medium‐grain (Jupiter) and a long‐grain (Wells) rice under similar germination conditions on their milling, physicochemical, and textural properties over the course of germination. Rough rice was soaked in water at 25°C for 12 h and then incubated at 30–34°C for four germination durations. Wells had a higher breakage percentage and a greater weight decrease than Jupiter during germination. Wells had a significantly lower GABA content before germination and at the first two germination durations than Jupiter, but the GABA content in Wells significantly increased at the third germination duration to become significantly higher than that of Jupiter. There were no significant changes in gelatinization temperatures and pasting properties of germinated rice from both cultivars at different germination durations. The cooked rice hardness from Wells decreased at the longest germination duration, whereas Jupiter showed a more significant decrease in cooked rice stickiness from germination. The results demonstrate that the impacts of germination on physical, chemical, and textural properties of rice were affected by grain type and germination duration.     

Zinc priming promotes seed germination and seedling vigor of rice

The present study evaluated effects of seed zinc (Zn) priming at concentrations from 0 to 25 mM ZnSO₄ on seedling vigor and viability in rice (Oryza sativa L.). Zinc priming substantially increased Zn concentration in the husk, but not in brown rice. The movement of primed Zn from the husk into the inner layers of rice seed during germination was suggested by Zn concentration declining in the husk coinciding with the increase in brown rice over time (r = –0.62; p < 1%), which did not happen in unprimed seed. Zinc priming significantly enhanced seedling growth and development up to 5 mM. Germination rate, root number, and dry weight were much higher than in unprimed seed, but higher Zn concentrations (10 and 25 mM) depressed seedling vigor. Priming rice seed with 2.5 mM Zn also improved the germination rate of rice in a Zn‐deficient soil, with or without soil Zn application. The results confirm that priming rice seed with Zn can improve germination and seedling vigor and for the first time show how Zn requirement of germinating rice seed and seedlings can be met by the prime Zn accumulated in the husk.     

Zinc absorption from low phytic acid genotypes of maize (Zea mays L.), Barley (Hordeum vulgare L.), and Rice (Oryza sativa L.) assessed in a suckling rat pup model

Dietary phytic acid is a major causative factor for low Zn bioavailability in many cereal- and legume-based diets. The bioavailability of Zn in seed of low phytic acid (lpa) variants of maize ( Zea mays L.), rice ( Oryza sativa L.), and barley ( Hordeum vulgare L.) was evaluated using a suckling rat pup model. Suckling rat pups (14 days old, n = 6-8/treatment) were fasted for 6 h and intubated with (65)Zn-radiolabeled suspensions prepared using seed produced by either wild-type (normal phytic acid) or lpa genotypes of each cereal. Test solutions were radiolabeled overnight (all genotypes) or immediately prior to intubation (barley genotypes). Pups were killed 6 h postintubation and tissues removed and counted in a gamma counter. Zn absorption was low from wild-type genotypes of maize (21, 33%) and rice (26%), and phytic acid reduction resulted in significantly higher Zn absorption, 47-52 and 35-52%, respectively. Zn absorption from wild-type barley incubated overnight was high (86-91%), and phytate reduction did not improve Zn absorption (84-90%), which is likely due to endogenous phytase activity. When the wild-type barley solutions were prepared immediately before intubation, Zn absorption was significantly lower (63, 78%) than from the lpa cultivars (92, 96%). Variation in seed or flour phenolic acid levels did not affect Zn absorption. Differences in seed Zn levels did not substantially affect Zn absorption. Thus, when phytic acid is abundant in a diet, it has a larger effect on Zn absorption than the level of Zn. Therefore, reducing the phytic acid content of staple cereal grains may contribute to enhancing Zn nutrition of populations consuming these staple foods.     

Effect of foliar application of zinc, selenium, and iron fertilizers on nutrients concentration and yield of rice grain in China

Zn, Se, and Fe levels in 65 Chinese rice samples were investigated, and the results indicated that these micronutrients contents of rice products from different location varied considerably. The mean contents of Zn, Se and Fe in these rice samples were 21.5+/-1.8, 0.020+/-0.012, and 12.4+/-4.3 mg kg(-1), respectively, which were too low to meet the micronutrient demands for the population feeding on the rice as staple. A field orthogonal experiment L9 (3(4)) was conducted on rice cultivar Wuyunjing 7, to evaluate the effect of Zn, Se, and Fe foliar fertilization on the concentration of these micronutrients, yield, and protein and ash content of rice grain. The results indicated that Zn and Se were the main variables influencing the Zn, Se, and Fe content of rice, and the optimal combination of fertilization for enhancing these micronutrients was 0.90 kg ha(-1) Zn, 0.015 kg ha(-1) Se, and 0.90 kg ha(-1) Fe. Under the optimal application condition, Zn, Se, and Fe content of rice could be significantly increased by 36.7%, 194.1%, and 37.1%, respectively, compared with the control, without affecting grain yield and protein and ash content of rice products. Moreover, in the confirmation experiment on rice cultivar Ninggeng 1, the optimal fertilization could increase the Zn, Se, and Fe content of rice up to 17.4, 0.123, and 14.2 mg kg(-1), respectively.     

Biofortification of common bean as a complementary approach to addressing zinc deficiency in South Africans

Deficiencies of vitamin A, iodine, iron and zinc (Zn) in humans are caused partly by the consumption of food that has insufficient quantities of these. Their deficiency has a negative impact on the health, wellbeing, social and economic status of human beings. A national survey conducted in 2012 identified deficiencies of vitamin A, Fe, and Zn among other nutrients in South Africans and regarded the deficiencies of vitamin A and Fe as a moderate but not Zn. This review discusses causes of Zn prevalence in low-income South Africans and that it is largely caused by the low content of Zn in their diets. Initiatives to reduce Zn deficiency include fortification of wheat products and maize meal which has failed to address it successfully. Weaknesses of fortification include high cost of fortified food products to low-income populations, poor regulation in ensuring compliance in fortification, non-fortification of sorghum meal, and leaching of fortified nutrients during processing. This review suggests Zn-biofortification of locally-preferred common bean cultivars as an alternative strategy to compliment fortification. The review also discusses advantages of adopting biofortified Nutritional Andean common beans. Furthermore, the review suggests initiatives including evaluation of the common bean genotypes’ adaptation to different agro-ecologies.     

提高发芽糙米得率的复合酶预处理工艺优化

为解决传统工艺生产发芽糙米浸泡时间长、生产效率低等问题,提出以纤维素酶和木聚糖酶的复合溶液代替蒸馏水浸泡发芽前糙米的新工艺。以糙米为原料,探究复合酶预处理工艺中酶解时间、酶解温度、复合酶浓度及配比对发芽糙米得率的影响规律,采用二次正交旋转中心组合设计试验,建立了各因素对发芽糙米得率影响的数学模型。结果表明:酶解时间、酶解温度、复合酶浓度及酶配比对发芽糙米得率影响显著(P0.05),得到优化参数组合为:酶解时间135 min,酶解温度35℃,复合酶浓度0.57 g/L、纤维素酶和木聚糖酶质量比1.86:1,在此条件下,与传统工艺相比浸泡时间缩短62.5%、发芽糙米得率及γ-氨基丁酸含量分别提高约3.90%和3.86 mg/(100 g)。通过对酶解后糙米皮层微观结构的观察分析,糙米皮层在复合酶作用下部分降解,胚乳中淀粉更易与水分子相结合,从而吸水速率提升。研究结果可为发芽糙米生产提供参考。     

不同白菜品种对锌的响应及锌利用效率研究

采用盆栽试验研究了白菜[Brassica campestris L.ssp.Chinensis(L.)Makino]4个品种对不同浓度锌(Zn 0、1、10 mg/kg)的响应.结果表明,白菜的生物量及体内锌含量随锌水平的增加而增加;但白菜品种对锌营养反应的敏感性不同.地上部锌含量、锌积累量和锌吸收效率均以日本华冠(J...     

Variation in Polyphenols,Tocols, γ‐Aminobutyric Acid,and Antioxidant Properties in Whole Grain Rice (Oryza sativa L.) as Affected by Different Germination Time

Dynamic alterations in the polyphenols, tocols, antioxidant activities (AOA), and γ‐aminobutyric acid (GABA) contents of white, red, and black germinated rice upon different germination periods were studied. The results indicated that the contents of the free, bound, and total phenolics and AOA steadily increased during germination, even though the free part of colored germinated brown rice (GBR) showed a notable decline at the earlier stages, but still higher than the white rice. The compositions of the nine phenolic acids and six tocols generally accumulated in a time‐ and variety‐dependent manner during the germination process. However, the contents of p‐coumaric, ferulic, and sinapic acids displayed a pronounced increase with the duration of germination in all cultivars. The GABA in white, red, and black GBR accumulated to the highest content at the end of germination, which was 4.7, 14.2, and 6.7‐fold of their respective nongerminated counterparts. Interestingly, the total anthocyanin content in black GBR displayed a constant drop at earlier stages and then a rise at the later stages. These results suggest that prolonged germination may further increase the functional properties of GBR.     

硫酸锌处理对玉米种子萌发的生理效应

以郑单958和农大108为材料,研究了硫酸锌浸种对老化玉米种子萌发及萌发过程中生理特性的影响。结果表明,适量的锌处理显著提高了玉米种子的发芽势、活力指数和单株幼苗干重,增强了种子萌发过程中的过氧化物酶(POD)、过氧化氢酶(CAT)、脱氢酶活性,降低了丙二醛(MDA)含量,增加了可溶性糖和可溶性蛋白含量。不同品种锌的适宜浓度不同,其中郑单958品种以0.4 g/L锌处理效果最好,而农大108品种以0.8 g/L的锌作用效果为佳。表明硫酸锌处理加快了玉米种子的萌发速率,提高了玉米种子萌发期间的抗氧化水平,减缓了脂质过氧化作用,促进了种子萌发时的物质代谢。     

Uptake of iron,zinc, manganese,and copper by seedlings of hybrid and traditional rice cultivars from different soil types 1

In pot experiments, uptake of zinc (Zn), copper (Cu), iron (Fe), and manganese (Mn) by hybrid rice from different soil types was compared with a traditional rice (Oryza sativa L.) cultivar. The concentration and total uptake of Fe in the shoots of hybrid rice grown in Oxisol and Ultisol were lower than those of the traditional cultivar. The concentration and total uptake of Zn in the shoots of hybrid rice grown in the Inceptisol (calcareous) were significantly higher than those of the traditional cultivar. Higher ratios of Zn and Fe in upper leaves (UL) to the lower leaves (LL) were found in hybrid rice grown in the calcareous Zn‐deficiency soil. The results indicated that hybrid rice root avoided absorbing excess Fe from Fe‐toxic soils due to its higher oxidizing power, and was more efficient in absorbing Zn from calcareous Zn‐deficient soils than the traditional cultivar.     

氮锌肥配施对南方香粳稻产量和品质的影响

【目的】研究氮锌肥配施对南方香粳稻产量和外观加工品质、蒸煮食味品质、香气的影响,为南方香粳稻的调优栽培提供科学依据。【方法】田间试验于2020和2021年在扬州大学试验基地进行,供试粳稻品种为宁香粳9号和南粳46。在施锌(+Zn)和不施锌(Zn0)条件下,分别设3个施氮水平：0 (N0)、180 kg/hm²(N180)、270 kg/hm²(N270),共6个处理。于收获期,测定产量和产量构成因素,分析籽粒加工外观、食味和香气品质。【结果】提高氮肥用量可显著增加香粳稻产量,而施用锌肥对香粳稻产量无显著影响,+ZnN270处理宁香粳9号和南粳46产量均最高,分别达10.48 t/hm²和10.40 t/hm²;相同氮肥用量下,增施锌肥对产量没有显著影响。宁香粳9号和南粳46的最佳稻米加工和外观品质均以+ZnN270处理最优。在相同氮肥用量下,施用锌肥改善了香粳稻的加工和外观品质。与N0处理相比,在N180和N270处理下两品种的直链淀粉含量下降了8.44%～13.16%,蛋白质含量增加了9.79%～...