Phytochemical Profiling and Assessment of Antidiabetic Activity of Curcuma Angustifolia Rhizome Methanolic Extract: An In Vitro and In Silico Analysis.

Curcuma angustifolia Roxb. is a plant with medicinal potential, traditionally used to treat different diseases. The present study aimed to determine the antidiabetic activity of C. angustifolia rhizome in vitro and in silico. The methanolic extract of C. angustifolia rhizome was analyzed by FTIR and GC-MS to determine the phytochemicals present. The antidiabetic potential of the extract was evaluated by different assays in vitro. The extract inhibited both α-amylase and α-glucosidase enzymes and the glucose diffusion through the dialysis membrane in a concentration-dependent manner with IC50 values of 530.39±0.09, 293.75±0.11, and 551.74±0.3 µg/ml respectively. The methanolic extract also improved yeast cell's ability to take up glucose across plasma membranes and the adsorption of glucose. The findings were supported by molecular docking studies. The results showed that the methanol extract of C. angustifolia rhizome has significant antidiabetic activity and thus can be also studied to isolate the potential compound with antidiabetic activities.

Assessment of the Anti-Breast Cancer Effects of Urolithin with Molecular Docking Studies in the In Vitro Condition: Introducing a Novel Chemotherapeutic Drug.

A lot of research has been done on using natural items as diabetes treatment. The molecular docking study was conducted to evaluate the inhibitory activities of urolithin A against α-amylase, α-glucosidase, and aldose reductase. The molecular docking calculations indicated the probable interactions and the characteristics of these contacts at an atomic level. The results of the docking calculations showed the docking score of urolithin A against α-amylase was -5.169 kcal/mol. This value for α-glucosidase and aldose reductase was -3.657 kcal/mol and -7.635 kcal/mol, respectively. In general, the outcomes of the docking calculations revealed that urolithin A can construct several hydrogen bonds and hydrophobic contacts with the assessed enzymes and reduces their activities considerably. The properties of urolithin against common human breast cancer cell lines, i.e., SkBr3, MDA-MB-231, MCF-7, Hs578T, Evsa-T, BT-549, AU565 and 600MPE were evaluated. The IC50 of the urolithin was 400, 443, 392, 418, 397, 530, 566 and 551 against SkBr3, MDA-MB-231, MCF-7, Hs578T, Evsa-T, BT-549, AU565 and 600MPE, respectively. After doing the clinical trial studies, the recent molecule may be used as an anti-breast cancer supplement in humans. IC50 values of urolithin A on α-amylase, α-glucosidase, and aldose reductase enzymes were obtained at 16.14, 1.06 and 98.73 µM, respectively.

HPA-SAM co-activation among racially diverse, economically disadvantaged early adolescents: Secondary analysis with a preliminary test of a multisystem, person-centered approach.

Investigating the co-activation of hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenomedullary (SAM) responses to acute stress can provide insight into how risk might become biologically embedded during early adolescence and improve understanding of what distinguishes physiological dysregulation from normative/expected physiological responses to stress. Evidence has thus far been mixed as to whether symmetric or asymmetric co-activation patterns are associated with higher exposure to chronic stress and poorer mental health outcomes during adolescence. This study expands on a prior multisystem, person-centered analysis of lower-risk, racially homogenous youth by focusing on HPA-SAM co-activation patterns in a higher-risk, racially diverse sample of early adolescents from low-income families (N = 119, Mage=11.79 years, 55.5% female, 52.7% mono-racial Black). The present study was conducted by performing secondary analysis of data from the baseline assessment of an intervention efficacy trial. Participants and caregivers completed questionnaires; youth also completed the Trier Social Stress Test-Modified (TSST-M) and provided six saliva samples. Multitrajectory modeling (MTM) of salivary cortisol and alpha-amylase levels identified four HPA-SAM co-activation profiles. In accordance with the asymmetric-risk model, youth exhibiting Low HPA-High SAM (n = 46) and High HPA-Low SAM (n = 28) profiles experienced more stressful life events, posttraumatic stress, and emotional and behavioral problems relative to Low HPA-Low SAM (n = 30) and High HPA-High SAM (n = 15) youth. Findings highlight potential differences in biological embedding of risk during early adolescence based on individuals' exposure to chronic stress and illustrate the utility of multisystem and person-centered approaches in understanding how risk might get "underneath the skin" across systems.

Exploring biological efficacy of novel benzothiazole linked 2,5-disubstituted-1,3,4-oxadiazole hybrids as efficient α-amylase inhibitors: Synthesis, characterization, inhibition, molecular docking, molecular dynamics and Monte Carlo based QSAR studies.

In an effort to explore a class of novel antidiabetic agents, we have made an effort to synergize the α-amylase inhibitory potential of 1,3-benzothiazole and 1,3,4-oxadiazole scaffolds by combining the two into a single structure via an ether linkage. The structure of synthesized benzothiazole clubbed oxadiazole derivatives are established by different spectral techniques. The synthesized hybrids are evaluated for their in vitro inhibitory potential against α-amylase. Compound 8f is found to be the most potent with a significant inhibition (87.5 ± 0.74% at 50 µg/mL, 82.27 ± 1.85% at 25 µg/mL and 79.94 ± 1.88% at 12.5 µg/mL) when compared to positive control acarbose (77.96 ± 2.06%, 71.17 ± 0.60%, 67.24 ± 1.16% at 50 µg/mL, 25 µg/mL and 12.5 µg/mL concentration). Molecular docking of the most potent enzyme inhibitor, 8f, shows promising interaction with the binding site of biological macromolecule Aspergillus oryzae α-amylase (PDB ID: 7TAA) and human pancreatic α-amylase (PDB ID: 3BAJ). To a step further, in-depth QSAR studies show a significant correlation between the experimental and the predicted inhibitory activities with the best Rvalidation2= 0.8701. The developed QSAR model can provide ample information about the structural features responsible for the increase and decrease of inhibitory activity. The mechanistic interpretation of the structure-activity relationship (SAR) is done with the help of combined computational calculations i.e. molecular docking and QSAR. Finally, molecular dynamic simulations are performed to get an insight into the binding mode of the most potent derivative with α-amylase from A. oryzae (PDB ID: 7TAA) and human pancreas (PDB ID: 3BAJ).

Assessment of Chemopreventive Potential of the Plant Extracts against Liver Cancer Using HepG2 Cell Line.

The edible parts of the plants Camellia sinensis, Vitis vinifera and Withania somnifera were extensively used in ancient practices such as Ayurveda, owing to their potent biomedical significance. They are very rich in secondary metabolites such as polyphenols, which are very good antioxidants and exhibit anti-carcinogenic properties. This study aims to evaluate the anti-cancerous properties of these plant crude extracts on human liver cancer HepG2 cells. The leaves of Camellia sinensis, Withania somnifera and the seeds of Vitis vinifera were collected and methanolic extracts were prepared. Then, these extracts were subjected to DPPH, α- amylase assays to determine the antioxidant properties. A MTT assay was performed to investigate the viability of the extracts of HepG2 cells, and the mode of cell death was detected by Ao/EtBr staining and flow cytometry with PI Annexin- V FITC dual staining. Then, the protein expression of BAX and BCl2 was studied using fluorescent dye to determine the regulation of the BAX and BCl2 genes. We observed that all the three extracts showed the presence of bioactive compounds such as polyphenols or phytochemicals. The W. somnifera bioactive compounds were found to have the highest anti-proliferative activity on human liver cancer cells.

Mentha pulegium L.: A Plant Underestimated for Its Toxicity to Be Recovered from the Perspective of the Circular Economy.

The aim of the study was to investigate the micromorphology of Mentha pulegium leaves and flowers harvested in three different Sicilian (Italy) areas with peculiar pedo-climatic conditions, and to characterize the phytochemical profile, the phytotoxic activity, and the eco-compatibility of their essential oils (EOs) for potential use as safe bioherbicides. Light microscopy (LM) and scanning electron microscopy (SEM) highlighted that M. pulegium indumentum consists of non-glandular and glandular trichomes of different types. Peltate trichomes of plants from the different sites showed few significant differences in dimension and abundance, but they were characterized by a surprisingly high number of secretory cells both in leaves and flowers. Phytochemical analyses showed that oxygenated monoterpenes were the most abundant class in all the EOs investigated (92.2-97.7%), but two different chemotypes, pulegone/isomenthone and piperitone/isomenthone, were found. The complex of morphological and phytochemical data indicates that soil salinity strongly affects the expression of the toxic metabolite pulegone, rather than the EO yield. Phytotoxicity tests showed a moderate activity of EOs against the selected species as confirmed by α-amylase assay. Moreover, the low toxicity on brine shrimp provided a rationale for the possible use of investigated EOs as eco-friendly herbicides.

Maltoheptaoside hydrolysis with chromatographic detection and starch hydrolysis with reducing sugar analysis: Comparison of assays allows assessment of the roles of direct α-amylase inhibition and starch complexation.

The aim was to determine inhibition of human α-amylase activity by (poly)phenols using maltoheptaoside as substrate with direct chromatographic product quantification, compared to hydrolysis of amylose and amylopectin estimated using 3,5-dinitrosalicylic acid. Acarbose exhibited similar IC50 values (50% inhibition) with maltoheptaoside, amylopectin or amylose as substrates (2.37 ± 0.11, 3.71 ± 0.12 and 2.08 ± 0.01 µM respectively). Epigallocatechin gallate, quercetagetin and punicalagin were weaker inhibitors of hydrolysis of maltoheptaoside (<50% inhibition) than amylose (IC50: epigallocatechin gallate = 20.41 ± 0.25 µM, quercetagetin = 30.15 ± 2.05 µM) or amylopectin. Interference using 3,5-dinitrosalicylic acid was in the order punicalagin > epigallocatechin gallate > quercetagetin, with minimal interference using maltoheptaoside as substrate. The main inhibition mechanism of epigallocatechin gallate and punicalagin was through complexation with starch, especially amylose, whereas only quercetagetin additionally binds to the α-amylase active site. Interference is minimised using maltoheptaoside as substrate with product detection by chromatography, potentially allowing assessment of direct enzyme inhibition by almost any compound.

Assessment of the Phenolic Profiles, Hypoglycemic Activity, and Molecular Mechanism of Different Highland Barley (Hordeum vulgare L.) Varieties.

The phenolic profiles, hypoglycemic activity, and molecular mechanism of the effect on type 2 diabetes mellitus (T2DM) of four highland barley varieties were investigated in the present study. The fundamental phenolics in highland barley were ferulic acid, naringin, and catechin, which mainly existed in bound form. These varieties showed favorable hypoglycemic activity via inhibition of α-glucosidase and α-amylase activities, enhancement of glucose consumption, glycogen accumulation and glycogen synthase 2 (GYS2) activity, and down-regulation of glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) activities. Specifically, ZQ320 variety exhibited the strongest hypoglycemic activity compared to the other varieties. Highland barley phenolics could inhibit gluconeogenesis and motivate glycogen synthesis via down-regulating the gene expression of G6Pase, PEPCK, and glycogen synthase kinase 3ß (GSK3ß), while activating the expression of insulin receptor substrate-1 (IRS-1), phosphatidylinositol 3 kinase (PI3K), serine/threonine kinase (Akt), GYS2, and glucose transporter type 4 (GLUT4). Therefore, phenolics from highland barley could be served as suitable candidates for therapeutic agent in T2DM to improve human health.

Bioconjugation as a smart immobilization approach for α-amylase enzyme using stimuli-responsive Eudragit-L100 polymer: a robust biocatalyst for applications in pharmaceutical industry.

Enzymes are powerful versatile biocatalysts, however, industrial application of enzymes is usually hampered by their susceptibility. Bio-inspired Eudragit-α-amylase conjugate (E-AC) was proposed as a biocatalyst for various pharmaceutical and industrial applications. In this study, α -Amylase (E.C. 3.2.1.1) was immobilized by covalent conjugation to Eudragit L-100 under mild conditions. The effect of polymer, carbodiimide and enzyme concentrations on optimization of (E-AC) was investigated. In addition, characterization of the free α -Amylase and E-AC with regard to pH, temperature, kinetic parameters, reusability and operational and storage conditions was carried out. Results showed a shift of the optimum pH of E-AC towards the alkaline side whereas, E-AC exhibited higher thermal stability at all tested temperatures. The kinetic parameters, Km values were 2.87 mg/ml and 3.15 mg/ml and Vmax values were 8.35 mg/ml/min and 8.98 mg/ml/min for free and E-AC, respectively. E-AC retained 85% of the initial activity after five consecutive amylolytic cycles, thus emphasizing its powerful potentials. Operational storage and thermal stability were highly improved as well for E-AC conjugate with an 11.6 stabilization factor in comparison to the free α-amylase. In this study, Eudragit L-100 polymer was successfully used as smart immobilization support to create a reversibly soluble-insoluble enzyme biocatalyst to enforce and extend biotechnological applications of α-amylase in the pharmaceutical industry.

Beyond model interpretability using LDA and decision trees for α-amylase and α-glucosidase inhibitor classification studies.

In this report are used two data sets involving the main antidiabetic enzyme targets α-amylase and α-glucosidase. The prediction of α-amylase and α-glucosidase inhibitory activity as antidiabetic is carried out using LDA and classification trees (CT). A large data set of 640 compounds for α-amylase and 1546 compounds in the case of α-glucosidase are selected to develop the tree model. In the case of CT-J48 have the better classification model performances for both targets with values above 80%-90% for the training and prediction sets, correspondingly. The best model shows an accuracy higher than 95% for training set; the model was also validated using 10-fold cross-validation procedure and through a test set achieving accuracy values of 85.32% and 86.80%, correspondingly. Additionally, the obtained model is compared with other approaches previously published in the international literature showing better results. Finally, we can say that the present results provided a double-target approach for increasing the estimation of antidiabetic chemicals identification aimed by double-way workflow in virtual screening pipelines.

Assessment of anxiety and stress markers in children submitted to educational strategies and ART-restoration: A randomized clinical trial.

OBJECTIVE: Although atraumatic restorative treatment (ART) is considered to be a good option for anxious patients, there is a lack of information whether ART associated to oral health educational strategy (OHES) would positively influence the level of anxiety and stress in children. This study aimed to evaluate the impact of OHES on anxiety and stress markers of schoolchildren submitted to ART. DESIGN: A sample of 78 six- to eight-year-old schoolchildren, with carious lesions in dentin, were randomly divided into groups: OHES + ART-group (n = 39) and ART-group (n = 39). OHES consisted of an educational interactive strategy performed once a week for four weeks. ART was performed using a standardized procedure with hand instruments and glass-ionomer cement. Anxiety and stress markers were assessed subjectively by the modified Venham Picture Test (m-VPT), modified Venham Anxiety Scale (m-VAS), while objective measures consisted of heart rate (HR) and salivary cortisol and alpha-amylase levels evaluated before, during and after treatment. RESULTS: The two groups did not differ in the perceived anxiety and in anxious behavior, and the variation along the treatment was not significant in both groups (p > 0.05). Both groups also showed higher HR "Before ART-restoration" than the other time-points as an anticipatory anxiety. ART group showed higher HR than OHES + ART group during the "Explanation of procedure" (p = 0.041) and "Deep excavation" (p = 0.018), and only ART group showed higher amylase levels "Before ART" compared to "After ART" (p = 0.004). CONCLUSIONS: It was concluded that OHES associated with ART showed a positive effect in modulating heart rate and alpha-amylase levels, that is, those markers of stress objectively measured during ART-restoration.

Cortisol and alpha-amylase assessment in psychotherapeutic intervention studies: A systematic review.

Dysregulations of the hypothalamus-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS), two of the most prominent stress-responsive systems, have been associated with the development and maintenance of various mental disorders. It has been suggested that these alterations might normalize in the course of psychotherapeutic interventions. We conducted a comprehensive review of psychotherapeutic intervention effects on HPA axis and ANS regulation in adult samples with mental disorders. We searched four databases for psychotherapeutic intervention studies with mentally ill patient samples, assessing cortisol and/or alpha-amylase before and after treatment. Study quality and confounder consideration within biomarker assessment were examined. Twenty-five studies were included. Psychotherapeutic interventions and biomarker assessment methodology varied substantially between studies. Accordingly, meta-analytical computations were deemed unfeasible. Study characteristics especially regarding cortisol and alpha-amylase assessment and analysis procedures were comprehensively reviewed. Study quality and biomarker confounder consideration ratings were mostly moderate to strong. Based on the results, we provide recommendations regarding intervention design and biomarker assessment methodology to increase comparability of psychotherapeutic treatment effects in future studies.

Psychological effects of exercise on community-dwelling older adults.

BACKGROUND: In recent years, there have been an increasing number of older adults who suffer from mental disorders globally. OBJECTIVE: The objective of this study was to examine the effect of an intervention that consisted of an exercise program to improve the mental health of community-dwelling older adults. PARTICIPANTS AND METHODS: The recruited participants of this study were community-dwelling older adults aged ≥60 years who participated in a comprehensive health promotion program in Kakogawa, Japan. Participants in the intervention group received an exercise program that was developed for older adults using Thera-Band. To measure participants' mental health status, a Japanese version of the short form of the Profile of Mood States (POMS-SF) was used. Stress markers were measured, such as salivary cortisol, alpha-amylase, and sIgA levels. All participants provided salivary samples and completed psychological questionnaires at baseline and 6-month follow-up. RESULTS: No significant differences were observed between the intervention and control groups with respect to POMS-SF score and salivary biomarker profile at baseline. After the intervention, the intervention group showed a significant decrease in the POMS-SF "fatigue" score and cortisol level. No significant changes were observed in the control group. CONCLUSION: Simultaneous changes in feelings of fatigue and cortisol levels were observed among subjects who had received the intervention of regular exercise. Further research is needed to investigate the effectiveness of exercise intervention in improving mental health among older adults.

An assessment of the nutraceutical potential of Juglans regia L. leaf powder in diabetic rats.

In this study, we evaluated the nutraceutical potential of Juglans regia L. (a dietary supplement and food-additive) by evaluating the in-vitro anti-diabetic potential and by assessing the in-vivo anti-hyperglycaemic, anti-hyperlipidaemic, and organ-protective effects of freshly-dried and powdered leaves of J. regia L. in diabetic rats. In the in-vivo experiments, dry powder of J. regia L. leaf (25, 50 and 100 mg/kg) was administered orally, twice daily (9.00 a.m. and 5 p.m.) to streptozocin-induced diabetic rats over a period of 28 days, during which body weight and blood glucose were monitored weekly. At the end of the experimental period, animals were sacrificed, blood was taken for assessment of lipid profile, antioxidant activity and liver/kidney biochemistry; while samples of the pancreas, liver and kidneys were fixed, processed, sectioned, and stained for general histology. Phytochemical evaluations of three extracts were carried out using HPLC-PDA validated procedures, while enzyme-inhibitory potentials were tested against α-amylase and α-glucosidase. In-vivo assays showed that twice-daily administration of J. regia L. leaf resulted in weight gain, glycaemic control, reversal of dyslipidaemia and biochemical evidences of liver/kidney injury, and protection against pancreas, liver and kidney tissue injury.

Single temperature liquefaction process at different operating pHs to improve ethanol production from Indian rice and corn feedstock.

Conventional grain ethanol manufacturing is a high-temperature energy-intensive process comprising of multiple-unit operations when combined with lower ethanol recovery results in higher production cost. In liquefaction, jet cooking accounts for significant energy cost, while strong acid or base used for pH adjustment presents a safety hazard. A need is felt for sustainable ethanol manufacturing process that is less hazardous, consumes lower energy, and operates in a low pH range of 4.50-5.50. A single temperature liquefaction (STL) process that could efficiently operate at lower liquefaction temperature over a pH range of 4.50-5.50 was developed using rice and corn feedstock. Ethanol recovery witnessed at pH 4.5, 5.0, and 5.5 are 481.2 ± 1.5, 492.4 ± 1.5, and 493.6 ± 1.5 L MT-1 rice, respectively. Similarly, ethanol recovery witnessed at pH 4.5, 5.0, and 5.5 are 404.6 ± 1.3, 413.9 ± 0.8, and 412.4 ± 1.8 L MT-1 corn, respectively. The improvement in ethanol recovery is attributed to higher starch conversion by alpha-amylase even at pH as low as 4.50. Thus, the STL process operated at pH lower than 5.20 is poised to enhance sustainability by offering dual advantage of energy as well as chemical saving.

Characteristics of Raw Starch-Digesting α-Amylase of Streptomyces badius DB-1 with Transglycosylation Activity and Its Applications.

Streptomyces badius DB-1 produces α-amylase extracellularly, and its production was enhanced 5.1-fold (from 9.47 ± 0.51 to 48.23 ± 1.45 U mL-1) due to optimization by one-variable-at-a-time and statistical approaches. Soluble starch emerged as the most influential factor that strongly affected enzyme production. The purified enzyme is a monomer with a molecular mass of ~57 kDa and optimally active at 50 °C and pH 6.0. The enzyme hydrolyzes soluble as well as raw starches into simpler sugars with a high proportion (>40.0 %) of maltotetraose. It is optimally active at moderate temperature and generates maltooligosaccharides from starch, thus, useful as an antistale in bread making. It also plays a role in increasing the formation of maltooligosaccharides due to transglycosylation activity, thus, finds application in functional foods. This is the first report on the production of raw starch-digesting α-amylase by S. badius with transglycosylation activity.

Development of an antidiabetic polyherbal formulation (ADPHF6) and assessment of its antioxidant activity against ROS-induced damage in pUC19 and human lymphocytes - an in vitro study.

BACKGROUND: Polyherbalism, an alternative natural-based therapy for various disorders, has been quoted about 1,300 years before in Sharangdhar Samhita. Herbal-based combination therapy stages a vital role for the treatment of type 2 diabetes mellitus (T2DM) and associated complications. The present study aims at developing an Ayurvedic-based polyherbal formulation (ADPHF6) and the assessing its antidiabetic and antioxidant property. METHODS: ADPHF6 polyherbal formulation was measured for phytochemical components by qualitative methods. The polyherbal formulation was quantitatively estimated for its phytochemical constituents, i. e. total phenol and flavonoid content. Further, the antioxidant property of ADPHF6 formulation was evaluated by 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging assay, hydrogen peroxide radical scavenging assay and metal chelating assay. α-Amylase and α-glucosidase inhibitory activities of polyherbal formulation were also assessed. ADPHF6 was further analysed for its protective antioxidant property against reactive oxygen species (ROS‾)-induced damage in human lymphocyte DNA and pUC19 plasmid. RESULTS: ADPHF6 polyherbal formulation revealed the presence of phytochemical constituents such as alkaloids, flavonoids, phenols, tannins, terpenoids, saponins and cardiac glycosides in significant levels. Further, it also measured the higher levels of total phenols (473.3±3.05 mg/g) and flavonoid (664±5.29 mg/g) content. Polyherbal formulation also exhibited IC50 values of 49.9±0.15, 65.1±0.10 and 60.1±0.05 mg/mL for 2,2- diphenyl-1-picryl-hydrazyl-hydrate (DPPH), hydrogen peroxide (H2O2) and Fe2+ radical scavenging activities, respectively. ADPHF6 revealed an inhibitory activity (IC50) of 0.67±0.01 and 0.81±0.01 mg/mL for α-amylase and glucosidase, respectively. Pre-treated human peripheral blood lymphocytes with ADPHF6 aqueous extract illustrated enhanced protection against ROS-mediated damage as compared with post-treated groups. DNA nicking assay rendered protective activity against the OH¯ radical-induced DNA damage in supercoiled pUC19 plasmid. CONCLUSIONS: Our present study demonstrates that ADPHF6 offers potent inhibitory activity against free radicals as well as digestive enzymes. However, studies should be conducted using in vivo model to further elucidate the effect against free radicals and its anti-hyperglycaemic activity in the management of non-insulin-dependent diabetes.

Modified Dietary Fiber from Cassava Pulp and Assessment of Mercury Bioaccessibility and Intestinal Uptake Using an In Vitro Digestion/Caco-2 Model System.

The ability of modified dietary fiber (MDF) generated from cassava pulp to modulate the bioaccessibility and intestinal absorption of heavy metals may be helpful to mitigate health risk associated with select foods including select fish high in methyl mercury. Using a coupled in vitro digestion/Caco-2 human intestinal cell model, the reduction of fish mercury bioaccessibility and intestinal uptake by MDF was investiaged. MDF was prepared from cassava pulp, a byproduct of tapioca production. The highest yield (79.68%) of MDF was obtained by enzymatic digestion with 0.1% α-amylase (w/v), 0.1% amyloglucosidase (v/v) and 1% neutrase (v/v). MDF and fish tissue were subjected to in vitro digestion and results suggest that MDF may reduce mercury bioaccessibility from fish to 34% to 85% compared to control in a dose-dependent manner. Additionally, accumulation of mercury from digesta containing fish and MDF was only modestly impacted by the presence of MDF. In conclusion, MDF prepared from cassava pulp may be useful as an ingredient to reduce mercury bioavailability from food such as fish specifically by inhibiting mercury transfer to the bioaccessibile fraction during digestion.

Performance Evaluation of a Salivary Amylase Biosensor for Stress Assessment in Military Field Research.

BACKGROUND: A convenient biosensor for real-time measurement of biomarkers for in-field psychophysiological stress research and military operations is desirable. We evaluated a hand-held device for measuring salivary amylase as a stress marker in medical technicians undergoing combat casualty care training using two different modalities in operating room and field settings. METHODS: Salivary amylase activity was measured by two biosensor methods: directly sampling saliva with a test strip placed under the tongue or pipetting a fixed volume of precollected saliva onto the test strip, followed by analyzing the sample on the strip using a biosensor. The two methods were compared for their accuracy and sensitivity to detect the stress response using an enzyme assay method as a standard. RESULTS: The measurements from the under-the-tongue method were not as consistent with those from the standard assay method as the values obtained from the pipetting method. The under-the-tongue method did not detect any significant increase in the amylase activity due to stress in the operating room (P > 0.1), in contrast to the significant increases observed using the pipetting method and assay method with a significance level less than 0.05 and 0.1, respectively. Furthermore, the under-the-tongue method showed no increased amylase activity in the field testing, while both the pipetting method and assay method showed increased amylase activity in the same group (P < 0.1). CONCLUSION: The accuracy and consistency of the biosensors need to be improved when used to directly measure salivary amylase activity under the tongue for stress assessment in military medical training.

In vitro digestibility of goat milk and kefir with a new standardised static digestion method (INFOGEST cost action) and bioactivities of the resultant peptides.

The hydrolysis degrees of goat milk and kefir during simulated gastrointestinal digestion and some bioactivities of the resulting peptides after fermentation and digestion were studied. A static in vitro digestion method by the COST FA1005 Action INFOGEST was used and goat milk and kefir were partially hydrolyzed during the gastric phase and had above 80% hydrolysis after duodenal digestion. There were no differences between the digestibility of goat milk and kefir (p > 0.05). Goat milk and kefir displayed about 7-fold antioxidant activity after digestion (p < 0.05). Fermentation showed no effect on the calcium-binding capacity of the samples (p > 0.05), however, after in vitro digestion calcium-binding capacity of the goat milk and kefir increased 2 and 5 fold, respectively (p < 0.05). Digested goat milk and kefir showed a higher dose-dependent inhibitory effect on α-amylase compared to undigested samples (p < 0.05). α-Glucosidase inhibitory activities and in vitro bile acid-binding capacities of the samples were not determined at the studied concentrations.