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In this research, parboiling was carried out at different times (5 and 15 min) on germinated paddy rice (GPR) from various basmati and non-basmati varieties. The results showed that as the parboiling time increased from 5 to 15 min, Δ $\Delta $ E, ash content, total dietary fiber, mineral content, cooking time, and textural properties increased while L*, lipid content, total starch, gruel solid loss, water absorption, oil absorption, foaming capacity, sugar profile, and total phenolic and flavonoid content decreased as compared to GPR. All pasting properties of GPR increased except breakdown as the parboiling time increased from 5 to 15 min. Parboiling altered the properties of GPR due to starch gelatinization. Total essential amino acid and gamma-aminobutyric acid decreased as the parboiling time (5 to 15 min) increased. The germinated parboiled brown rice could create a highly nutritious alternative to regular brown rice as it offers improved texture and cooking qualities.

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This article examined the effect of geographical (different climate conditions) and floral origins on some quality parameters of honey including the activity of diastase enzyme. Moreover, some non-quality parameters were investigated such as the pH, fructose, glucose, ratio of fructose/glucose and invertase. The honey samples were collected from Asir (cold climate) and Jazan (hot climate) regions at the southwestern part of Saudi Arabia. The geographical origin significantly affected the mean value moisture of the Acacia honey (p-value = 0.02), conductivity of the polyfloral honey (p-value = 0.03), sucrose of the Acacia honey (p-value = 0.02), diastase activity of the Acacia (p-value = 0.001), Ziziphus (p-value = 0.046) and polyfloral honey (p-value ≤ 0.001), fructose of the Acacia honey (p-value = 0.01), glucose of the Ziziphus honey (p-value = 0.03), fructose/ glucose ratio of the Ziziphus honey (p-value = 0.035), and invertase activity of the polyfloral honey (p-value ≤ 0.001). Regarding the effect of the floral origin of the honey from Asir region, the sucrose percentage of the Acacia honey was significantly more than that of the polyfloral honey (p- value = 0.003), the diastase activity of the Acacia honey was significantly more than its activity in the Ziziphus honey (p- value = 0.044), glucose percentage of the Ziziphus honey was significantly more the glucose percentage of the Acacia honey (p-value = 0.009) and the fructose/ glucose ratio of the Ziziphus honey was significantly more than that of the Acacia and polyforal honeys (p-value = 0.011 and p-value = 0.045, respectively). Concerning the significant effects of the floral origin on the quality parameters of the honey samples from Jazan region, the moisture of the Ziziphus honey was significantly increased when compared to the moisture of the Acacia honey (p-value = 0.038), the acidity of the polfloral honey was significantly more than the acidity of the Acacia honey (p-value = 0.049), the sum of fructose and glucose of the polyfloral honey was significantly increased compared to that of the Acacia honey (p-value = 0.015), the pH of the Ziziphus hiney was significantly more than the pH of the polyfloral honey (0.011) and the fructose of the polfloral honey was significantly more than that of the Acacia honey (p-value = 0.031). The effect of the geographical origin of the honey samples on their quality parameters depends on their floral origin and the effect of their floral origin differs according to their geographical origin. This article suggests considering collectively the geographical and floral origins effect when developing honey standards. However, the Codex standards for honey started considering this issue when it changed the standard concentration of HMF in honey from not more than 80-40 mg/Kg for honeys from cold climate and 80 mg/Kg for honeys from hot climates.

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Buritirana (Mauritella armata) is a fruit from a native Brazilian palm tree whose economic and industrial potential is still little explored. The nutritional composition and carbohydrates; organic acids; fatty acids; triacylglycerol; and phenolics profile of buritirana pulp, shells, and seeds were performed in this study. In addition, pH, color, ant total carotenoid, phenolic, flavonoids, flavonols, tannins, and antioxidant potential (ABTS, DPPH, ILP, FRAP, CUPRAC, and TRC) were determined in these parts of the fruit. The results indicated high lipid content and energy value for pulp (30.53 g 100 g-1, and 351.21 kcal 100 g-1, respectively) and shells (18.41 g 100 g-1, and 276.73 kcal 100 g-1, respectively). On the other hand, high fiber (63.09 g 100 g-1), starch (2.66 g 100 g-1), and carbohydrates (28.60 g 100 g-1) contents were observed for the seeds. Glucose was the main carbohydrate found in pulp and seed, while sucrose was the main sugar in shells. Tartaric acid was the predominant organic acid in pulp and shells (16.60 and 10.96 mg 100 g-1, respectively), while malic acid was the main organic acid in seeds (58.78 mg 100 g-1). Oleic and palmitic acid were the main fatty acids detected in buritirana pulp, shells, and seeds. Buritirana pulp and shells showed a high content of total phenolic and total flavonoid (918.58 and 940.63 mg GAE 100 g-1; and 679.31 and 444.94 mg CE 100 g-1, respectively). Moreover, a high antioxidant potential (DPPH•, CUPRAC, and ILP) was observed in the extracts obtained from pulp and shells. The pulp showed a significant content of carotenoids (270.23 µg g-1). Among the 28 phenolic compounds determined in buritirana pulp and seeds, and 27 in shells, 22 (pulp and seeds), and 21 (shells) were reported by first time in the literature. Ferulic acid in pulp and shells (99.39 and 111.69 µg g-1) and pinocembrin in seeds (19.21 µg g-1) were the main phenolic compounds identified in buritirana. Multivariate analysis showed high correlation of phenolic compounds on antioxidant potential. The results showed that buritirana is rich in nutrients and bioactive products and can be fully utilized. The products resulting from buritirana processing can be applied in the food, cosmetics, and pharmaceutical industries.

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OBJECTIVE: To evaluate 4-point per day self-monitoring of blood glucose (SMBG) every 2 weeks compared with every week. METHODS: A total of 104 patients with lifestyle-controlled gestational diabetes (GDMA1) were randomized to 2-weekly or weekly 4-point per day (fasting on awakening and 2-h post-meals) SMBG. Primary outcome was the change in glycated hemoglobin (HbA1c) level from enrollment to 36 weeks of pregnancy across trial arms. The non-inferiority margin was an HbA1c increase of 0.2%. RESULTS: The mean difference for change in HbA1c from enrollment to 36 weeks was 0.003% (95% confidence interval [CI] -0.098% to +0.093%), within the 0.2% non-inferiority margin. The change in HbA1c level increased significantly within both trial arms-0.275% ± 0.241% (P < 0.001) in 2-weekly arm versus 0.277% ± 0.236% (P < 0.001) in the weekly arm. Participants randomized to 2-weekly SMBG were significantly less likely to receive anti-glycemic treatment-5/52 (9.6%) versus 14/50 (28.0%) (relative risk 0.34, 95% CI 0.13-0.88; P = 0.017). All secondary outcomes-maternal weight gain, preterm delivery, cesarean delivery, birthweight, and neonatal admission-were not significantly different. CONCLUSIONS: In GDMA1, 2-weekly is non-inferior to weekly SMBG on the change in HbA1c level. Two-weekly SMBG appeared to be adequate for monitoring women with GDMA1. CLINICAL TRIAL REGISTRATION: This study was registered in ISRCTN registry on March 25, 2022 with trial identification number: ISRCTN13404790 (https://doi.org/10.1186/ISRCTN13404790). The first participant was recruited on April 12, 2022.

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Sauce-flavor Daqu is an important source of fermentation power in baijiu brewing. Revealing carbohydrate metabolism will help to explore the underlying reasons for the difference in fermentation performance of Daqu. In this study, metagenomic and metaproteomic technologies were performed to explore the carbohydrate metabolism network and its active functional microorganisms of Sauce-flavor Daqu. The sugar profile was analyzed using LC-MS to confirm the metabolic network. The results showed that 23 fungi and 5 bacteria were involved in carbohydrate metabolism. Starch metabolism, cellulose metabolism, and glucan metabolism were the main metabolic pathways, in which fungi especially Aspergillus were more involved than bacteria. Among these active microorganisms, Saccharomycopsis fibuligera, Aspergillus oryzae, Monascus purpureus, Byssochlamys spectabilis, Lichtheimia ramosa, Thermomyces lanuginosus, and Thermoascus aurantiacus were significant functional microorganisms with the ability to produce multiple enzymes. Lichtheimia ramosa, Lichtheimia corymbifera and Kroppenstedtia eburnea were biomarkers of Daqu in the first round, granting it a better liquefaction ability. ß-amylase derived from wheat also played an important role in starch degradation, and the synergistic effect with α-amylase endowed Daqu with higher liquefaction power in the first two rounds. The results of this study are of great significance for the analysis of the mechanism of Daqu fermentation and provide a reliable theoretical basis for strengthening the fermentation performance of Daqu.

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Background: The International Diabetes Federation estimates that 16.2% of livebirths in 2017 were affected by hyperglycemia in pregnancy, with 85.1% due to gestational diabetes mellitus (GDM). Daily blood glucose monitoring compared with alternate day testing in mild GDM is associated with similar pregnancy outcomes. Data are sparse on the ideal frequency for self-monitoring of blood glucose (SMBG) in mild GDM for glycemic control. A higher HbA1c at late pregnancy is associated with adverse pregnancy outcomes. We sought to evaluate three days compared to one day per week of four-point self-monitoring of blood glucose (SMBG) in gestational diabetes mellitus (GDM) controlled by lifestyle changes for glycemic control. Methods: This randomized trial was conducted from February−December 2018. A total of 106 women with lifestyle-controlled GDM were randomized to three days (SMBG3) or one day (SMBG1) per week of four-point (fasting and two-hours post-meal) SMBG. The primary outcome was the change in the HbA1c level at recruitment and 36-weeks gestation within and across trial arms. The student t-test was used for between-arm analyses and a paired t-test for within-arm analyses. Results: The HbA1c level through pregnancy increased significantly in both trial arms: mean increase of 0.21% ± 0.26%, p < 0.001 (SMBG3), and 0.19% ± 0.24%, p < 0.001 (SMBG1), but the 0.02% difference across trial arms was not significant (p = 0.79). Maternal weight gain (3.1 ± 2.1 kg vs. 3.3 ± 3.0 kg, p = 0.72), cesarean delivery (24/52 (48%) vs. 23/53 (43%), RR 1.06, 95% CI: 0.69−1.62, p = 0.77), neonatal birthweight (3.1 ± 0.4 kg vs. 3.0 ± 0.4 kg, p = 0.53) and neonatal intensive care unit admission (4/52 (8%) vs. 3/53 (6%), RR 1.36, 95% CI: 0.32−5.78, p = 0.68) were not significantly different for SMBG3 vs. SMBG1, respectively. Other maternal and neonatal secondary outcomes were not significantly different. Conclusion: In mild GDM, three days compared to one day per week showed a similar HbA1c levels change at 36-weeks gestation. Maternal and neonatal outcomes were also not significantly different. Less frequent monitoring of SMBG as a standard of care in mild GDM deserves further study and consideration.

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Demand for honeydew honey (HDH) is growing, both from consumers and the food industry, due to its potential antimicrobial, anti-inflammatory, and antioxidant properties. However, information on the chemical profile of HDH remains scant, particularly on New Zealand honeydew honey (NZHDH). This paper aims to provide a comprehensive chemical analysis of NZHDH produced from honeybees, which feed on nectar exuded by the scale insect Ultracoelostoma assimile. This insect feeds on most species of the Southern Beech (Nothofagus spp.). The proximate composition, mineral profile, sugar profile, phenolic profile, amino acid profile, and antioxidant activity of NZHDH was determined and compared to results for HDH and other varieties of honey previously reported in literature. It was determined that the antioxidant activity of NZHDH is comparable to several studies on Manuka honey, which is widely considered as the "gold standard" for its antioxidant activity. This demonstrated that NZHDH indeed had excellent antioxidant properties. This study was the first time that a quantitative amino acid profile has been produced for NZHDH. The major amino acids were proline, L-aspartic acid, L-glutamic acid, L-alaine, and L-phenylalanine. The major phenolic compounds were pinocembrin, abscisic acid, and pinobanksin. Of the phenolic compounds quantified in this study, only p-hydroxybenzoic acid has previously been quantified in NZHDH.

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Background: To study maternal-fetal outcomes in patients of GDM diagnosed by International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria but subsequently using a twenty-four-hour seven-value sugar profile to evaluate patients before instituting management. Methods: This prospective observational study was conducted at a tertiary hospital in New Delhi, India, over a period of one year. During this period, women diagnosed as GDM between 24 and 28 weeks of gestation using IADPSG criteria underwent seven-value sugar profile in twenty-four hours before initiating any therapy. Those with normal profile were kept on observation only, whereas others were managed by Medical Nutrition Therapy (MNT) with or without pharmacotherapy as required to maintain euglycemia. Maternal and fetal outcomes were documented and analysed to detect differences between the groups. Results: Out of 2279 pregnant women, 201 (8.8%) were diagnosed as GDM. The twenty-four-hour seven-value sugar profile was normal in 78 (38.8%) patients, who were managed only by close observation. Treatment was given to other patients; 93 (46.2%) patients were managed with MNT only, whereas pharmacotherapy by way of metformin was added to 22 (10.9%) patients and 8 (3.9%) patients required insulin. Differences in maternal-fetal outcomes between the treated and untreated groups were not found to be statistically significant. Conclusions: The policy of evaluating patients with twenty-four-hour seven-value sugar profile after an abnormal Oral Glucose Tolerance Test eliminated over one-third women from receiving treatment and interventions for GDM without compromising maternal-fetal outcomes.

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In recent years, an increasing interest in reducing sugar consumption has been observed and many studies are conducted on the use of polyols in the osmotic dehydration process to obtain candied or dried fruits. The studies in the literature have focused on the kinetics of the process as well as the basic physical properties. In the scientific literature, there is a lack of investigation of the influence of such polyol solutions such as sorbitol and mannitol used as osmotic substances during the osmotic dehydration process on the contents of bioactive components, including natural colourants. Thus, the aim of the study was to evaluate the impact of polyols (mannitol and sorbitol) in different concentrations on the process kinetics and on chosen physical (colour and structural changes) as well as chemical (sugars and polyol content, total anthocyanin content, total polyphenol content, vitamin C, antioxidant activity) properties of osmotic-dehydrated organic strawberries. Generally, the results showed that the best solution for osmotic dehydration is 30% or 40% sorbitol solutions, while mannitol solution is not recommended due to difficulties with preparing a high-concentration solution and its crystallization in the tissue. In the case of sorbitol, the changes of bioactive compounds, as well as colour change, were similar to the sucrose solution. However, the profile of the sugar changed significantly, in which sucrose, glucose, and fructose were reduced in organic strawberries and were partially replaced by polyols.

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The benefits of natural honeybee products (e.g., honey, royal jelly, beeswax, propolis, beevenom and pollen) to the immune system are remarkable, and many of them are involved in the induction of antibody production, maturation of immune cells and stimulation of the immune system. The type of plants in the geographical area, climatic conditions and production method have a significantly influence on the nutritional quality of honey. However, this variability can influence consumer liking by the sensory attributes of the product. The aim of this work was to compare the most popular honeys from Poland in terms of nutritional value, organoleptic properties and antioxidant activity. In the study, five varieties of honey (honeydew, forest, buckwheat, linden and dandelion) from conventional and organic production methods were tested. The nutritional characteristics of honey samples included acidity, content of water, sugars, vitamin C, HMF and phenolics (total and flavonoids), while honey color, taste, aroma and consistency were investigated in the organoleptic characteristics. The antioxidant activity was determined in water- and ethanol-soluble honey extracts using DPPH and ORAC tests. The results showed that organoleptic and nutritional characteristics of popular Polish honeys differ significantly in relation to plant source and production method. The significant effect of honey variety on the content of HMF, saccharose and phenolics, as well as acidity and antioxidant capacity were noted. The impact of variety and variety × production method interaction was significant in the case of the content of vitamin C, glucose and fructose. A visible difference of buckwheat and forest honeys from other samples was observed. The highest content of total phenolics with antioxidant activity based on the SET mechanism was found in buckwheat honeys, while forest honeys were richer in flavonoids.

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The present study aimed to investigate the effect of initial vacuum package (VP), air package (AP) and salt-solution package (NP) on texture softening and package-swelling of Paocai by comparing the changes in physicochemical properties, pectinolysis, microstructure, microbial profile, as well as sugar and organic acid profiles during storage. Results showed that, when compared with AP and NP, with suppressive microbial invasion and less total pectinase activity, VP could retain more soluble pectin and induce more compact microstructure of Paocai, leading to higher hardness of Paocai during storage. As for package-swelling, VP mitigated gas-production in package by changing the microbial composition and metabolic patterns of sugar and organic acid in Paocai, especially targeted regulating the abundance of genus Kazachstania. This study provided a perspective for appropriate packaging technology to control the pectinase activity as well as cell-invading and gas-producing microorganisms for manufacturing fermented vegetable with better texture and non-package-swelling.

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Green macroalgae comprise significant amount of structural carbohydrates for their conversion to liquid biofuels. However, it generally relies on species characteristics and the variability in seasonal profile to determine its route for bioprocessing. Hence, this study was conducted to analyze the indigenous marine macroalgal strain (Ulva prolifera) with respect to periodic trend and reducing sugar extraction. Consequently, in our investigation, the monthly variation in sugar profile and bioethanol yield was assessed between the monsoon and post-monsoon seasons, of which relatively high reducing sugar and fermentative bioethanol yield of about 0.152 ± 0.009 g/gdw and 6.275 ± 0.161 g/L was obtained for the October-month isolate (MITM10). Thereafter, the biochemical profile of this collected biomass (MITM10) revealed carbohydrate 34.98 ± 3.30%, protein 12.45 ± 0.49%, and lipid 1.93 ± 0.07%, respectively, on dry weight basis. Of these, the total carbohydrate fraction yielded the maximum reducing sugar of 0.156 ± 0.005 g/gdw under optimal conditions (11.07% (w/v) dosage, 0.9 M H2SO4, 121°C for 50 min) for thermal-acid hydrolysis. Furthermore, the elimination of polysaccharides was confirmed using the characterization techniques scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Therefore, the present thermochemical treatment method provides a species-specific novel strategy to breakdown the macroalgal cell wall polysaccharides that enhances sugar extraction for its utilization as an efficient bioenergy resource.

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BACKGROUND: Antenatal corticosteroids (ACS) are increasingly used to improve prematurity-related neonatal outcome. A recognized and common adverse effect from administration of antenatal corticosteroid is maternal hyperglycemia. Even normal pregnancy is characterized by relative insulin resistance and glucose intolerance. Treatment of maternal hyperglycemia after ACS might be indicated due to the higher risk of neonatal acidosis which may coincide with premature birth. Metformin is increasingly used to manage diabetes mellitus during pregnancy as it is effective and more patient friendly. There is no data on prophylactic metformin to maintain euglycemia following antenatal corticosteroids administration. METHODS: A double blind randomized trial. 103 women scheduled to receive two doses of 12-mg intramuscular dexamethasone 12-hour apart were separately randomized to take prophylactic metformin or placebo after stratification according to their gestational diabetes (GDM) status. First oral dose of allocated study drug was taken at enrolment and continued 500 mg twice daily for 72 hours if not delivered. Six-point blood sugar profiles were obtained each day (pre- and two-hour post breakfast, lunch and dinner) for up to three consecutive days. A hyperglycemic episode is defined as capillary glucose fasting/pre-meal ≥ 5.3 mmol/L or two-hour post prandial/meal ≥ 6.7 mmol/L. Primary outcome was hyperglycemic episodes on Day-1 (first six blood sugar profile points) following antenatal corticosteroids. RESULTS: Number of hyperglycemic episodes on the first day were not significantly different (mean ± standard deviation) 3.9 ± 1.4 (metformin) vs. 4.1 ± 1.6 (placebo) p = 0.64. Hyperglycemic episodes markedly reduced on second day in both arms to 0.9 ± 1.0 (metformin) vs. 1.2 ± 1.0 (placebo) p = 0.15 and further reduced to 0.6 ± 1.0 (metformin) vs. 0.7 ± 1.0 (placebo) p = 0.67 on third day. Hypoglycemic episodes during the 3-day study period were few and all other secondary outcomes were not significantly different. CONCLUSIONS: In euglycemic and diet controllable gestational diabetes mellitus women, antenatal corticosteroids cause sustained maternal hyperglycemia only on Day-1. The magnitude of Day-1 hyperglycemia is generally low. Prophylactic metformin does not reduce antenatal corticosteroids' hyperglycemic effect. TRIAL REGISTRATION: The trial is registered in the ISRCTN registry on May 4 2017 with trial identifier https://doi.org/10.1186/ISRCTN10156101 .

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PURPOSE: To compare 3 consecutive days of hyperglycemic response following antenatal dexamethasone regimens of 12-mg or 6-mg doses 12 hourly in diet-controlled gestational diabetes. METHODS: A randomized controlled trial was carried out in a university hospital in Malaysia. Women with lifestyle-controlled gestational diabetes scheduled to receive clinically indicated antenatal corticosteroids (dexamethasone) were randomized to 12-mg 12 hourly for one day (2 × 12-mg) or 6-mg 12-hourly for two days (4 × 6-mg). 6-point (pre and 2-h postprandial) daily self-monitoring of capillary blood sugar profile for up to 3 consecutive days was started after the first dexamethasone injection. Hyperglycemia is defined as blood glucose pre-meal ≥ 5.3 or 2 h postprandial ≥ 6.7 mmol/L. The primary outcome was a number of hyperglycemic episodes in Day-1 (first 6 BSP points). A sample size of 30 per group (N = 60) was planned. RESULTS: Median [interquartile range] hyperglycemic episodes 4 [2.5-5] vs. 4 [3-5] p = 0.3 in the first day, 3 [2-4] vs. 1 [0-3] p = 0.01 on the second day, 0 [0-1] vs. 0 [0-1] p = 0.6 on the third day and over the entire 3 trial days 7 [6-9] vs. 6 [4-8] p = 0.17 for 6-mg vs. 12-mg arms, respectively. 2/30 (7%) in each arm received an anti-glycemic agent during the 3-day trial period (capillary glucose exceeded 11 mmol/L). Mean birth weight (2.89 vs. 2.49 kg p < 0.01) and gestational age at delivery (37.7 vs. 36.6 weeks p = 0.03) were higher and median delivery blood loss (300 vs. 400 ml p = 0.02) was lower in the 12-mg arm; all other secondary outcomes were not significantly different. CONCLUSION: In gestational diabetes, 2 × 12-mg could be preferred over 4 × 6-mg dexamethasone as hyperglycemic episodes were fewer on Day-2, fewer injections were needed and the regimen was completed sooner. CLINICAL TRIAL REGISTRATION: http://www.isrctn.com/ISRCTN16613220 .

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Eugenia stipitata is a fruit native to the Brazilian Amazonian region, belonging to the Myrtaceae family whose chemical composition has been little evidenced. In this study, we evaluated for the first time the nutritional composition, bioactive compounds and antioxidant properties of two fractions of this fruit. It was observed that the edible fraction had a higher content of minerals such as K, Ca and Mg (827.66 ± 14.51; 107.16 ± 1.54; and 75.65 ± 1.28 mg 100 g-1 dw, respectively), sucrose (38.01 ± 2.94 mg g-1 dw), fructose (17.58 ± 0.80 mg g-1 dw), and maltotetraose (1.63 ± 0.09 mg g-1 dw). In this same fraction, about 30 volatile compounds were found, mainly biciclo(3.2.1)octan-3-one, 6 (2-hydroxyethyl)-, endo-; butanoic acid, 2-methyl-, hexyl ester and p-ocimene. In turn, the seed had the highest number of compounds identified by ESI-LTQ-MS/MS (including vanillic acid, gallic acid hexoside, catechin hexoside, luteolin hexoside, among others), higher content of phenolics (142.43 ± 0.82 mg GAE g-1 dw), flavonoids (43.73 ± 0.23 mg CE g-1 dw), and antioxidant capacity (139.59 ± 2.47; 447.94 ± 2.70; and 100.07 ± 10.50 µM TE g-1 dw for DPPH, ABTS, and ORAC, respectively). These results suggest that Eugenia stipitata has excellent nutritional value and great functional potential, and may contribute to a greater commercial exploitation of this fruit, not only in food, but also in the pharmaceutical and cosmetic industries.

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Mannooligosaccharides (MOSs) are one of the most commonly used biomass-derived feed additives. The effectiveness of MOS varies with the length of oligosaccharides, medium length MOSs such as mannotetraose and mannopentaose being the most efficient. This study aims at improving specificity of ß-mannanase from Aspergillus niger toward the desirable product size through rational-based enzyme engineering. Tyr 42 and Tyr 132 were mutated to Gly to extend the substrate binding site, allowing higher molecular weight MOS to non-catalytically bind to the enzyme. Hydrolysis product content was analyzed by high-performance anion-exchange chromatography with pulsed amperometric detection. Instead of mannobiose, the enzyme variants yielded mannotriose and mannotetraose as the major products, followed by mannobiose and mannopentaose. Overall, 42% improvement in production yield of highly active mannotetraose and mannopentaose was achieved. This validates the use of engineered ß-mannanase to selectively produce larger MOS, making them promising candidates for large-scale MOS enzymatic production process.

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This study was carried out to compare the antioxidant and nutritional properties of coconut (Cocos nucifera L.) sap with other natural sources of sugar such as sugar palm (Borassus flabellifer) and sugarcane (Saccharum officinarum L.). Coconut sap and juice from sugar palm and sugarcane were analyzed for proximate composition, pH and total soluble solid (TSS), color, sugar profile, vitamin profile, antioxidant properties (total phenolic contents, DPPH, FRAP, and ABTS), and mineral content. The results indicated that coconut sap possesses high DPPH (23.42%), FRAP (2.09 mM/ml), and ABTS (21.85%) compared with the juices. Coconut sap also had high vitamin C (116.19 µg/ml) and ash (0.27%) contents, especially in potassium (960.87 mg/L) and sodium (183.21 mg/L) which also indicating high content of minerals. These properties showed that coconut sap could be served as a potential healthier sugar source compared with sugar palm and sugarcane juices.

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BACKGROUND: Coconut sugar has a caramel color with a taste like brown sugar. It is commonly used as natural sweetener. However, coconut sugar has been produced from coconut sap using a traditional method that involves heating the sap at high temperature (>100 °C) in an open pan for a long period (3-5 h). This conventional method results in an over-cooked sugar, which leads to quality deterioration in terms of both its physical and chemical properties. The current study aimed to investigate the processing of coconut sap into sugar syrup using alternative processing techniques such as rotary vacuum evaporation (RE) and microwave evaporation (ME), comparing them with open-heat evaporation (OHE) technique. RESULTS: Coconut sugar syrup produced by rotary evaporation at 60 °C and 250 mbar vacuum (RE-60) required the shortest production time (12.2 min) and the lowest processing temperature (54.8 °C) when compared with ME (13 min and 103.2 °C) and OHE (46.8 min and 101.6 °C). It also had a light brownish color with a higher L* value (35.17) than the ME (29.84) and OHE (23.84) methods. It was found to contain higher amounts of monosaccharides (fructose and glucose) and lower amounts of disaccharides (sucrose). Furthermore, the amount of energy required for RE-60 (0.35 kWh) was much less than for OHE (0.83 kWh). CONCLUSION: This study provided an alternative processing method for the sugar processing industry to produce coconut sugar using the rotary evaporation method at 60 °C under 250 mbar vacuum with better physicochemical qualities, shorter processing time, and minimum input energy. © 2020 Society of Chemical Industry.

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The berry of Physalis peruviana L. (Solanaceae) represents an important socio-economical commodity for Latin America. The absence of a clear phenotype renders it difficult to trace its place of origin. In this study, Cape gooseberries from eight different regions within the Peruvian Andes were profiled for their metabolism implementing a NMR platform. Twenty-four compounds could be unequivocally identified and sixteen quantified. One-way ANOVA and post-hoc Tukey test revealed that all of the quantified metabolites changed significantly among regions: Bambamarca I showed the most accumulated significant differences. The coefficient of variation demonstrated high phenotypic plasticity for amino acids, while sugars displayed low phenotypic plasticity. Correlation analysis highlighted the closely coordinated behavior of the amino acid profile. Finally, PLS-DA revealed a clear separation among the regions based on their metabolic profiles, accentuating the discriminatory capacity of NMR in establishing significant phytochemical differences between producing regions of the fruit of P. peruviana L.

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Honey is a food of high importance due to its nutritional value. The effect of late harvest and pollen composition on honey quality and antimicrobial activity was studied. Different physicochemical parameters were determined as quality indicators. The HMF content, diastase activity, sugar content, antimicrobial activity, and hydrogen peroxide content were selected in current work as the crucial parameters for evaluation. The results proved that the late harvested honey sample showed a vast number of pollens from different blossom periods. The hydrogen peroxide content and antimicrobial activity of late harvested honey was significantly increased (proved by t-test), whereas the honey seems to be affected significantly from weather conditions since the HMF content was also increased. The diastase activity was proved to be lower than the respective in fresh honey, whereas no difference was observed on the sugar content. Finally, the effect of origin and processing in late harvested honey was discussed.

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