Exploring Appropriate Reference Intervals and Clinical Decision Limits for Glucose-6-Phosphate Dehydrogenase Activity in Individuals From Guangzhou, China.

Background: Quantitative detection of glucose-6-phosphate dehydrogenase (G6PD) is commonly done to screen for G6PD deficiency. However, current reference intervals (RIs) of G6PD are unsuitable for evaluating G6PD-activity levels with local populations or associating G6PD variants with hemolysis risk to aid clinical decision-making. We explored appropriate RIs and clinical decision limits (CDLs) for G6PD activity in individuals from Guangzhou, China. Methods: We enrolled 5,852 unrelated individuals between 2020 and 2022 and screened their samples in quantitative assays for G6PD activity. We conducted further investigations, including G6PD genotyping, thalassemia genotyping, follow-up analysis, and statistical analysis, for different groups. Results: In Guangzhou, the RIs for the G6PD activities were 11.20-20.04 U/g Hb in male and 12.29-23.16 U/g Hb in female. The adjusted male median and normal male median (NMM) values were 15.47 U/g Hb and 15.51 U/g Hb, respectively. A threshold of 45% of the NMM could be used as a CDL to estimate the probability of G6PD variants. Our results revealed high hemolysis-risk CDLs (male: <10% of the NMM, female: <30% of the NMM), medium hemolysis-risk CDLs (male: 10%-45% of the NMM, female: 30%-79% of the NMM), and low hemolysis-risk CDLs (male: ≥ 45% of the NMM, female: ≥ 79% of the NMM). Conclusions: Collectively, our findings contribute to a more accurate evaluation of G6PD-activity levels within the local population and provide valuable insights for clinical decision-making. Specifically, identifying threshold values for G6PD variants and hemolysis risk enables improved prediction and management of G6PD deficiency, ultimately enhancing patient care and treatment outcomes.

Gut microbiota changes in animal models of spinal cord injury: a preclinical systematic review and meta-analysis.

BACKGROUND: An increasing number of studies show that the intestinal flora is closely related to spinal cord injury. Many researchers are exploring the changes in the richness, diversity, and evenness of intestinal flora in spinal cord injury animal models to identify the characteristic bacteria. METHODS: A comprehensive literature search was conducted using three databases: PubMed, Embase, and Web of Science. A meta-analysis was performed using R 4.3.1 to evaluate the comparison of microbiota diversity, richness, and evenness and the relative abundance of intestinal microbiota in animals with spinal cord injury and blank controls. RESULTS: Fifteen studies were included in the meta-analysis, of which 12 involved gut microbiota distribution indicators and 11 included intestinal microflora relative abundance indicators. Meta-analysis of high-dimensional indicators describing the distribution of the gut microbiota identified a substantial decline in the evenness and richness of the intestinal flora. In addition, the Actinobacteria phylum and Erysipelotrichales and Clostridiales orders were significantly different between the spinal cord injury and sham groups; therefore, they may be the characteristic bacteria in spinal cord injury models. CONCLUSION: Our meta-analysis suggested that the gut microbiota in the spinal cord injury animal model group was altered compared with that in the control group, with varying degrees of changes in richness and evenness and potentially pathogenic characteristic flora. More rigorous methodological studies are needed because of the high heterogeneity and limited sample size. Further research is needed to clinically apply intestinal microbiota and potentially guide fecal microbiota transplantation therapy.

Our meta-analysis showed that spinal cord injury significantly decreased the richness and evenness of intestinal flora in experimental animals.No statistically significant changes in the phyla flora during spinal cord injury have been found.Erysipelotrichales and Clostridiales may be the characteristic flora of gut microbiota changes during spinal cord injury.

Effect of Esketamine Gargle on Postoperative Sore Throat in Patients Undergoing Double-Lumen Endobronchial Intubation: A Randomised Controlled Trial.

Background: Postoperative sore throat is a frequent adverse event after double-lumen endobronchial tube (DLT) intubation. The aim of this study was to investigate whether esketamine gargle has a preventive effect on the incidence of postoperative sore throat in patients undergoing DLT intubation. Methods: This trial included 140 patients undergoing elective thoracic surgery at the third affiliated hospital of Sun Yat-Sen University. Patients were randomly allocated into the following two groups of 70 patients each: the control group, gargling with saline of 30 mL, and the esketamine group, gargling with an esketamine solution of 30 mL (2 mL/50 mg esketamine in 28 mL saline), 5 min prior to anaesthesia induction. The primary outcome was the incidence of sore throat 24 h after surgery. The main secondary outcomes included the incidence of sore throat and hoarseness at 1 h and 48 h after surgery, as well as the intraoperative haemodynamic responses. Results: The incidence of sore throat was significantly higher in the control group (47.1%, 33/70 patients) compared with the esketamine group (12.9%, 9/70 patients) at 24 h after surgery (RD, 0.41; 95% confidence interval, 0.26-0.57; p < 0.001). Furthermore, the incidence of sore throat at 1 h (p = 0.027), 24 h (p = 0.019), and seventh day (p = 0.031) as well as hoarseness at 1 h (p = 0.027), 24 h (p = 0.019), and 48 h (p = 0.031) after surgery were reduced in the esketamine group. Significant differences were seen in the peak levels of systolic blood pressure, mean arterial blood pressure, and heart rate between the groups during the intubation (p < 0.05). Besides, no patient developed an adverse reaction to esketamine. Conclusion: Preoperative gargling of esketamine can provide an effect against sore throat after DLT intubation without adverse side effects and effectively inhibit sharp elevations in heart rate and blood pressure during double-lumen intubation procedures.

Astrocyte senescence-like response related to peripheral nerve injury-induced neuropathic pain.

BACKGROUND: Peripheral nerve damage causes neuroinflammation, which plays a critical role in establishing and maintaining neuropathic pain (NeP). The mechanisms contributing to neuroinflammation remain poorly elucidated, and pharmacological strategies for NeP are limited. Thus, in this study, we planned to explore the possible link between astrocyte senescence and NeP disorders following chronic sciatic nerve injury. METHODS: An NeP animal model was established by inducing chronic constrictive injury (CCI) to the sciatic nerve in adult rats. A senolytic drug combination of dasatinib and quercetin was gavaged daily from the first postoperative day until the end of the study. Paw mechanical withdrawal threshold (PMWT) and paw thermal withdrawal latency (PTWL) were evaluated to assess behaviors in response to pain in the experimental rats. Senescence-associated ß-galactosidase staining, western blot analysis, and immunofluorescence were applied to examine the levels of proinflammatory factors and severity of the senescence-like response in the spinal cord. Lipopolysaccharide (LPS) was administered to induce senescence of spinal astrocytes in primary cultures in vitro, to explore the potential impacts of senescence on the secretion of proinflammatory factors. Furthermore, single-cell RNA sequencing (scRNA-seq) was conducted to identify senescence-related molecular responses in spinal astrocytes under neuropathic pain. RESULTS: Following sciatic nerve CCI, rats exhibited reduced PMWT and PTWL, increased levels of spinal proinflammatory factors, and an enhanced degree of senescence in spinal astrocytes. Treatment with dasatinib and quercetin effectively attenuated spinal neuroinflammation and mitigated the hypersensitivities of the rats subjected to sciatic nerve CCI. Mechanistically, the dasatinib-quercetin combination reversed senescence in LPS-stimulated primary cultured astrocytes and decreased the levels of proinflammatory factors. The scRNA-seq data revealed four potential senescence-related genes in the spinal astrocyte population, and the expression of clusterin (CLU) protein was validated via in vitro experiments. CONCLUSION: The findings indicate the potential role of astrocyte senescence in neuroinflammation following peripheral nerve injury, and suggest that targeting CLU activation in astrocytes might provide a novel therapeutic strategy to treat NeP.

Bone marrow-derived mesenchymal stem cells attenuate complete Freund's adjuvant-induced inflammatory pain by inhibiting the expression of P2X3.

Bone marrow-derived mesenchymal stem cells (BMSCs) show a good property for pain treatment by modulating inflammatory response. However, the underlying therapeutic effect and related mechanism of BMSCs on inflammatory pain remain unclear. Therefore, we explored the function and potential mechanism of BMSCs performing in a complete Freund's adjuvant (CFA)-induced inflammatory pain model in this study. Here, BMSCs were injected into the CFA-treated rats, and we used behavioural tests to evaluate the changes in hypersensitivity. High-throughput sequencing was used to screen out the hub genes. Molecular biology experiments were performed to detect the level of P2X3 or inflammatory mediators in rats and observed the distribution of P2X3 in neural cells. Furthermore, the function of the P2X3 was explored via inhibitor and activator experiments. Finally, we found that BMSCs alleviated hyperalgesia and spinal levels of pro-inflammatory factors in CFA-treated rats. High-throughput sequencing showed that P2X3 and P2X7 were identified as hub genes, and only the expression level of P2X3 was significantly down-regulated after BMSCs treatment. Immunohistochemistry showed that P2X3 mainly colocalized with microglia and astrocytes. The levels of P2X3 and pro-inflammatory factors were all significantly reduced after BMSC injection. Moreover, similar attenuation was found in the CFA-treated rats after injecting the P2X3 inhibitor, and a P2X3 antagonist reversed the attenuation induced by the BMSCs. These findings suggest that BMSCs exerted a therapeutic effect on inflammatory pain by inhibiting the expression of P2X3 and the excessive production of inflammatory mediators was associated with an increased P2X3 level and BMSC therapy reverse these effects.

Intrathecal liproxstatin-1 delivery inhibits ferroptosis and attenuates mechanical and thermal hypersensitivities in rats with complete Freund's adjuvant-induced inflammatory pain.

Previous studies have confirmed the relationship between iron-dependent ferroptosis and a peripheral nerve injury-induced neuropathic pain model. However, the role of ferroptosis in inflammatory pain remains inconclusive. Therefore, we aimed to explore whether ferroptosis in the spinal cord and dorsal root ganglion contributes to complete Freund's adjuvant (CFA)-induced painful behaviors in rats. Our results revealed that various biochemical and morphological changes were associated with ferroptosis in the spinal cord and dorsal root ganglion tissues of CFA rats. These changes included iron overload, enhanced lipid peroxidation, disorders of anti-acyl-coenzyme A synthetase long-chain family member 4 and glutathione peroxidase 4 levels, and abnormal morphological changes in mitochondria. Intrathecal treatment of liproxstatin-1 (a ferroptosis inhibitor) reversed these ferroptosis-related changes and alleviated mechanical and thermal hypersensitivities in CFA rats. Our study demonstrated the occurrence of ferroptosis in the spinal cord and dorsal root ganglion tissues in a rodent model of inflammatory pain and indicated that intrathecal administration of ferroptosis inhibitors, such as liproxstatin-1, is a potential therapeutic strategy for treating inflammatory pain.

Global Trends and Hotspots in Esketamine Research: A Bibliometric Analysis of Past and Estimation of Future Trends.

Background: Being the S-enantiomer of racemic ketamine, esketamine is found to be effective for sedation, analgesia, and treating depression. However, there is no comprehensive bibliometric analysis about esketamine research. In this study, we aimed to determine the scientific output and emerging topics related to esketamine. Methods: Esketamine-related articles and reviews that published between 2000 and 2020 were obtained from the Web of Science Core Collection database, using key word search of "esketamine" "esketamine hydrochloride", "s-ketamine", "S(+)-ketamine", "(S)-ketamine", or "(-)-ketamine". Various bibliographic elements were collected, including the annual number of publications, citation frequency, countries/regions, institutions, authors, journals, and keywords. Two sorts of scientometric software, namely VOS viewer and CiteSpace, were used to conduct bibliometric and knowledge-map analyses. Results: A total of 683 publications were included in the current study. We found the number of publications in esketamine research field had increased annually since 2016. The United States was the leader in this field, with the highest publications number (162, 23.72%), total citations (3504/9713, 36.08%) and H-index (40). The most productive institution was Chiba University in Japan, and esketamine-related papers were mainly published in the journal Anesthesia & Analgesia. The keyword co-occurrence analysis showed that keywords relevant to depression were the most frequent. Moreover, all identified keywords could be divided into four clusters, with the research focus gradually shifting from cluster of "anesthesia and analgesia detection" to "depression treatment effect.". Conclusion: The past two decades have shown a marked increase in esketamine research. The United States maintained a top position worldwide, making the most significant contributions in the field of esketamine research. The contributions and collaborations of Asian countries have continuously increased and is a strong area of growth as well as development in recent years. Additionally, the emerging hotspots of esketamine research concentrate on clarifying its depression treatment effect.

The distribution of phosphorus, carotenoids and tocochromanols in grains of four Chinese maize (Zea mays L.) varieties.

Grains of three specialty maize varieties and one conventional maize variety cultivated in China were collected and dissected to obtain the germ, endosperm, and pericarp fraction, and the distribution pattern of phosphorus, carotenoids, and tocochromanols was determined. The results showed that phytochemical contents varied significantly among different maize fractions. The germ fraction accounted for 78.3 to 86.5% of the total phosphorus present in the maize kernels. Over 86.9% of carotenoids were located in the endosperm. Except for waxy maize, 64.5 to 74.8% of the tocochromanols were contributed by the germ. Considerable differences in phytochemical contents were observed between the genotypes. Waxy maize contained the highest content of tocopherols, tocotrienols and tocochromanols meanwhile waxy maize had the lowest carotenoid and phytate phosphorus content. High lysine maize contained the highest levels in carotenoids and lowest tocochromanols. Over all, total carotenoids were significantly inversely associated with total tocochromanols.

Mechanism differences between reductive and oxidative dough rheology improvers in the formation of 1D and 3D gluten network.

Gluten network formed by oxidation of glutenin sulfhydryl groups is the determinant of dough rheological properties, while chemical reagents including oxidants and reductants are both used as dough rheology improvers under different circumstances. This study compares the impact of sodium metabisulfite (SMBS) and azodicarbonamide (ADA), as the representative reductive and oxidative dough improvers, at series of concentrations that offer or remove the same number of electrons form dough, respectively. The alveographic characterization, protein distribution and glutenin composition analysis, and free sulfhydryl measurement were performed on dough containing redox equivalent SMBS or ADA. Finally, at each optimal concentration, the dough protein network was analyzed with confocal microscopy. Results showed that SMBS increased the free sulfhydryl content, loosened the microstructure of gluten network, and thus enhanced dough extensibility. ADA reduced the free sulfhydryl content, compacted the dough microstructure, thus enhanced the tenacity and baking strength of dough. It is therefore proposed that the reductants reduce disulfide bonds in gluten network and renders the formation of one-dimensional gluten network while oxidants promote the disulfide linkage and formation of three-dimensional gluten network. This study offers a theoretic foundation of differentiating dough rheology improvers for their specified application.

Alterations in gut microflora populations and brush border functionality following intra-amniotic administration (Gallus gallus) of wheat bran prebiotic extracts.

Wheat bran is the by-product of milling wheat flour which is one of the richest sources of dietary fiber, and cellulase that can be used for increasing the soluble dietary fiber. We hypothesize that wheat bran prebiotics would improve mineral-metabolism gene expression, and intestinal functionality, and increase health-promoting bacterial populations in vivo (Gallus gallus). By using the intra-amniotic administration procedure, five groups (non-injected; 18 Ω H2O; 100 mg mL-1 wheat bran prebiotics; 100 mg mL-1 cellulase wheat bran prebiotics; 50 mg mL-1 Arbinose) were utilized. Upon hatch, the cecum, small intestine and liver were collected for assessment. The results indicated that wheat bran prebiotics significantly up regulated the expression of certain brush border membrane functional genes, and mineral metabolism related proteins, in addition to increasing the intestinal beneficial bacterial populations. Prebiotics from wheat bran, cellulase wheat bran and arabinose increased the intestinal villi height, and goblet cell diameters and numbers.

Effects of enzymes to improve sensory quality of frozen dough bread and analysis on its mechanism.

Baking quality of frozen dough is negatively affected by dough weakening and by a reduction in both yeast viability and activity during freezing and frozen storage. The objective of this study was to investigate effects of different enzymes, such as α-amylase, xylanase, celluase, glucose oxidase, and lipase on the texture and sensory quality of bread after frozen storage, as well as on dough properties, in terms of fermentation characteristics, freezable water contents and microstructure. Except for α-amylase, other enzymes improved the bread sensory quality and got higher overall acceptability, especially xylanase. Dough fermentative behavior showed that the maximum heights of frozen dough were increased by 33.2, 19.7 and 7.4%, respectively with xylanase, cellulase and lipase. Cellulase lowered gas holding ability of dough. Thermodynamic properties indicated that addition of enzyme decreased the freezable water contents in frozen dough. Scanning electronic microscopy revealed that freezing and frozen storage disrupted dough gluten network causing separation of starch granules from the gluten matrix. Inclusion of cellulase, xylanase and lipase made the frozen dough having a more continuous gluten network and smoother surface, and glucose oxidase increased the stability of the gluten work.

Effects of dough mixing time before adding konjac glucomannan on the quality of noodles.

In this study, effects of 5% konjac glucomannan (KGM) blended with low-protein flour at different dough mixing duration on the properties of dough and noodles were investigated. To prepare the KGM noodle samples, 5% KGM was added after low-protein flour mixed with water for 0, 2 and 4 min, respectively. The three samples above were defined as T0 KGM, T2 KGM and T4 KGM noodle samples, respectively. The results revealed that the elastic modulus (G') and viscous modulus (G″) of dough both increased with extending dough mixing time before adding KGM. T4 KGM samples showed the least cooking loss. Textural properties including hardness, cohesiveness and tensile strength of KGM noodles had a tendency to increase with a longer dough mixing time before adding KGM. Microstructure of dough and noodles confirmed that a longer dough mixing time before adding KGM made microstructure more compact with a thickened gluten matrix. The sensory quality of the T2 KGM and T4 KGM samples was better than that of the T0 KGM samples.

Robertsonian translocations: an overview of 872 Robertsonian translocations identified in a diagnostic laboratory in China.

Robertsonian translocations (ROBs) have an estimated incidence rate of 1/1000 births, making this type of rearrangement the most common structural chromosomal abnormalities seen in the general population. In this study, we reports 872 cases of ROBs from 205,001 specimens karyotyped postnatally in a single accredited laboratory in China, including 583 balanced ROBs, 264 unbalanced ROBs, 9 mosaic ROBs, and 18 complex ROBs. Ninety-three percent of the balanced ROBs observed were adults with infertility, miscarriage, or offspring(s) with known chromosomal abnormalities. Significant excess of females were found to be carriers of balanced ROBs with an adjusted male/female ratio of 0.77. Ninety-eight percent of the unbalanced ROBs observed were children with variable referral reasons. Almost all of the unbalanced ROBs involved chromosome 21 except a single ROB with [46,XX,der(13;14),+13] identified in a newborn girl with multiple congenital anomalies. Multiple novel ROB karyotypes were reported in this report. This study represents the largest collections of ROBs in Chinese population.

Mixing, tensile and pasting properties of wheat flour mixed with raw and enzyme treated rice bran.

Rice bran is a potential fiber and minerals source for nutrients enhancement of cereals food. For evaluation of rice bran applied in bread making, mixing properties, tensile and pasting properties of wheat flour dough with raw (RB) or enzymes treated rice bran (ERB) were investigated. Farinogram with two peaks, which was observed in the dough with 40 % ERB, was reported. For mixing properties, addition of RB and ERB significantly decreased water absorption and stability of wheat dough. Dough development time of mixed flour with ERB was longer than that with RB. Water absorption, stability time of the dough and farinograph quality number is negatively correlated with addition of RB and ERB. The alveograph tests indicated that extensibility of dough decreased remarkably with increased RB or ERB addition and RB had more negative effects than that of the ERB. Results of pasting behaviors predicted that addition of RB or ERB, could slow down starch retrogradation and delay bread staling. In general, wheat flour mixed with 20 % RB or ERB was fit for bread making and the later expects better sensory and nutritional values.

Effect of a small amount of sodium carbonate on konjac glucomannan-induced changes in thermal behavior of wheat starch.

The effects of konjac glucomannan (KGM) on thermal behavior of wheat starch have been studied in the presence of low concentrations of Na2CO3 (0.1-0.2 wt% of starch). Confocal laser scanning microscopy (CLSM) allows the visualization of the starch gelatinization process and granule remnants in starch pastes. Heating the starch dispersion in KGM-Na2CO3 solution significantly delays granule swelling and inhibits amylose leaching, whereas Na2CO3 alone, at the same concentration, has little effect. Na2CO3 assists KGM in producing the extremely high viscosity of starch paste, attributing to a less remarkable breakdown of viscosity in subsequent heating, and protecting starch granules against crystallite melting. The distinct partially networked film around the surface of starch granules is evident in the CLSM images. We propose that Na2CO3 could trigger the formation of complexes between KGM and starch polymers, which exerts a protective effect on granular structure and modifying gelatinization characteristics of the mixtures.

Phytase activity in brown rice during steeping and sprouting.

Phytase in brown rice will be activated and accumulated during seed germination. Changes of phytase activity in brown rice during two stages of germination (steeping and sprouting) affected by process conditions were studied. It was shown that steeping led to significant decrease of phytase activity (p < 0.01), varying with steeping temperature and steeping medium composition. Steeping respectively in demineralized water, 0.5 mM CaCl2 and 0.1 M H2O2 at 20 °C for 24 h led to the lowest phytase activity in brown rice, which was only 25% of that in raw rice. At steeping stage, steeping media had no significant effect. During the sprouting stage, phytase activity increased with prolonged time and gradually reached stable levels, and with higher temperature in the range of 15-25 °C. Phytase activity in brown rice reached 320-340 U kg-(1) after 5 d sprouting. The evolution pattern of phytase activity during sprouting differed with the solutes previously used during steeping. Steeping either with CaCl2 or H2O2 caused a delay followed by a rapid activation of phytase, while for control, a gradual accumulation of phytase activity was observed. Compared with acidic and alkaline steeping solutions, demineralized water at neutral (6.8) pH provided the best pre-treatment prior to sprouting at 25 °C, to activate maximum levels of phytase. Extreme conditions, either strong acidic or alkaline inhibited activation of phytase, and changed appearance of brown rice kernel as well.

Effect of neutrase, alcalase, and papain hydrolysis of whey protein concentrates on iron uptake by Caco-2 cells.

Effects of enzymatic hydrolysates of whey protein concentrates (WPC) on iron absorption were studied using in vitro digestion combined with Caco-2 cell models for improved iron absorption. Neutrase- and papain-treated WPC could improve iron absorption; especially hydrolysates by Neutrase could significantly increase iron absorption to 12.8% compared to 3.8% in the control. Hydrolysates by alcalase had negative effects to the lowest at 0.57%. Two new bands at molecular weights (MW) around and below 10 kDa occurred at tricine-SDS-PAGE of hydrolysates by Neutrase, and one new band at MW below 10 kDa occurred in hydrolysates by papain. No new band was observed in hydrolysates by alcalase. Concentration of free amino acids indicated that, except for tyrosine and phenylalanine, amino acids in papain-treated hydrolysates were higher than that of alcalase, and no cysteine and proline were found in hydrolysates by alcalase. The results suggested that hydrolysate by Neutrase-treated WPC is a promising facilitator for iron absorption. Peptides of MW around and lower than 10 kDa and aspartic acid, serine, glutamic acid, glycin, cysteine, histidine, and proline may be contributors to enhancement.

In vitro solubility of calcium, iron and zinc in relation to phytic acid levels in rice-based consumer products in China.

In vitro solubility of calcium, iron and zinc in relation to phytic acid (PA) levels in 30 commercial rice-based foods from China was studied. Solubility of minerals and molar ratios of PA to minerals varied with degrees of processing. In primary products, [PA]/[Ca] values were less than 5 and [PA]/[Fe] and [PA]/[Zn] similarly ranged between 5 and 74, with most values between 20 and 30. [PA]/[mineral] molar ratios in intensively processed products were lower. Solubility of calcium ranged from 0% to 87%, with the lowest in brown rice (12%) and the highest in infant foods (50%). Iron solubility in two-thirds of samples was lower than 30%, and that of zinc narrowly ranged from 6% to 30%. Solubility of minerals was not significantly affected by [PA]/[mineral]. At present, neither primary nor intensively processed rice-based products are good dietary sources of minerals. Improvements should be attempted by dephytinization, mineral fortification or, preferably, combination of both.

In vitro solubility of calcium, iron, and zinc in rice bran treated with phytase, cellulase, and protease.

Absorption of minerals is inhibited by phytic acid, fiber, and protein because of the chelates formed. Response surface method (RSM) was used in this study to evaluate the effect of application of commercial phytase, protease, and cellulase in rice bran on the in vitro solubility of calcium (IVCa), iron (IVFe), and zinc (IVZn). It is shown that IVCa and IVZn were significantly improved by the application of phytase and cellulase, and the models of two second-order polynomials are recommended for prediction, with coefficients at R(2) = 0.86 and R(2) = 0.88, respectively. Interaction between protease and cellulase also significantly affected IVCa and IVZn. Cellulase had more efficiency than phytase on IVCa. Differing in its effect on Ca and Zn, phytase had a significant linear correlation with IVFe, and none of the other processing parameters exerted a significant effect. The largest increment for IVFe, IVCa, and IVZn occurred in the treatment with applications of phytase at 2.5 U g(-1) and protease and cellulase at 0.2% and 1%, respectively, which were 3.3, 3.6, and 4.3 times, respectively, that of the untreated material.

Effects of soaking, germination and fermentation on phytic acid, total and in vitro soluble zinc in brown rice.

Rice is an important staple food in Asian countries. In rural areas it is also a major source of micronutrients. Unfortunately, the bioavailability of minerals, e.g. zinc from rice, is low because it is present as an insoluble complex with food components such as phytic acid. We investigated the effects of soaking, germination and fermentation with an aim to reduce the content of phytic acid, while maintaining sufficient levels of zinc, in the expectation of increasing its bioavailability. Fermentation treatments were most effective in decreasing phytic acid (56-96% removal), followed by soaking at 10°C after preheating (42-59%). Steeping of intact kernels for 24h at 25°C had the least effect on phytic acid removal (<20%). With increased germination periods at 30°C, phytic acid removal progressed from 4% to 60%. Most wet processing procedures, except soaking after wet preheating, caused a loss of dry mass and zinc (1-20%). In vitro solubility, as a percentage of total zinc in soaked rice, was significantly higher than in untreated brown rice while, in steeped brown rice, it was lower (p<0.05). Fermentation and germination did not have significant effects on the solubility of zinc. The expected improvement due to lower phytic acid levels was not confirmed by increasing levels of in vitro soluble zinc. This may result from zinc complexation to other food components.