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Bu çalışmanın amacı, farklı kurutma metotlarının (dondurarak kurutma, sıcak hava, vakum ve mikrodalga kurutma) balkabağı posasının (BP) renk parametreleri, toplam fenolik (TF) içeriği, toplam flavonoid (TFl) içeriği ve antioksidan aktivite (AA) üzerindeki etkisini gözlemlemektir. Ek olarak, fenolik madde ekstraksiyon koşulları Yanıt Yüzey Yöntemi ile dondurularak kurutulmuş BP ekstraktı kullanılarak optimize edilmiştir. BP kurutma koşulları; sıcak hava ve vakum kurutma için 30 ve 60 °C ve mikrodalga kurutma için 120 ve 600 W olarak belirlenmiştir. Kurutulmuş BP için; TF içeriği, TFl içeriği ve AA sırasıyla 1.88 ± 0.01- 4.86 ± 0.27 mg gallik asit eşdeğeri/g kuru madde, 1.32 ± 0.05-3.09 ± 0.29 mg kateşin eşdeğeri/g kuru madde ve 1.45 ± 0.15-4.27 ± 0.27 mg askorbik asit eş değeri/g kuru madde arasında değişmiştir. Bu çalışma kurutulmuş BP’nin biyoaktif potansiyeline bağlı olarak fonksiyonel bir bileşen olarak kullanılabileceğini göstermiştir.

The aim of this study was to investigate the effect of essential oil (EO) addition (1, 2, and 3% v/v) obtained from different plants (Santolina chamaecyparissus (SC), Schinus molle (SM), and Eucalyptus globulus (EG) on the antimicrobial, physical, water vapor permeability, mechanical, optical and microstructural properties of the carboxymethyl cellulose (CMC) films. The films containing EO at the concentration of 3% showed the highest antimicrobial activity on tested microorganisms. The EO content increase from 1% to 3% in films decreased the moisture content and water solubility of all films. The water vapor permeability also decreased in films with EGEO but it increased in films with SCEO and SMEO. While the tensile strength (TS) of films containing EO (29.43 ± 3.28–77.05 ± 0.02 MPa) was determined higher than the TS of the control (24.60 ± 0.54 MPa), the elongation at break (E%) of films (14.41 ± 0.02–33.01 ± 0.01%) were lower than E% of the control (37.06 ± 0.85%). The microstructures of films were homogeneous in the films containing 1% and 2% EOs. CMC films gained a significant antimicrobial property and improved its characteristic properties with the incorporation of EOs presenting a good potential for applying to foods.

OBJECTIVES: To analyze the role of each subunit from Sucrase-Isomaltase (SI) and Maltase-Glucoamylase (MG) on the glucose production from corn starch (NC), Waxy starch (WX) and Hylon V (HLV) starch predigested with pancreatic amylase (Amy). METHODS: The starches were selected based on their ratios of α-1,4 and α-1,6 linkages. Starches were predigested with Amy for 0, 10, 20, 30, 60 and 120 min. After predigestion starches were hydrolyzed with different combinations of recombinant C terminal (C) and N terminal (N) subunits of Sucrase-Isomaltase (SI) and Maltase-Glucoamylase (MG), each at the relative maltase activity of: 40% C-SI, 20% N-SI, 32% C-MG and 8% N-MG, resembling the observed in the human intestinal mucosa. Glucose release was quantified by a real-time glucose oxidase-peroxidase method at 37°C. RESULTS: C-MG subunit hydrolyzed the three starches without predigestion by Amy at rates of 2.9 ± 0.02, 2.5 ± 0.02 and 2.4 ± 0.05 ng/min of glucose for WX, HLV and NC, respectively. C-SI subunit produced only 0.9 ± 0.02 ng/min glucose from the starches not predigested by Amy. After 30 min of Amy predigestion, the rates of glucose release by C-MG were modified to 13.3 ± 0.09, 12.3 ± 0.08 and 11.6 ± 0.08 ng/min for HLV, NC and WX, respectively. The same predigestion modified glucose release by C-SI subunit to 3.9 ± 0.02, 4.7 ± 0.08 and 5.8 ± 0.03 for WX, NC and HLV, respectively. In starches predigested 60 or 120 min, C-MG subunit alone or together with N-MG showed lower activity than expected, suggesting the occurrence of substrate inhibition. Together the four MG and SI subunits showed clear differences on the rates of glucose production from the starches predigested with Amy for 120 min (22.8 ± 0.133 for WX, 26.4 ± 0.2 for NC and 26.7 ± 0.8 for HLV; all ng/min) which correlated with the glucose production by the N and C SI subunits together (15.5 ± 0.9 for WX, 19.4 ± 0.09 for NC and 23.85 ± 0.12 for HLV; all ng/min). CONCLUSIONS: We found complex interactions among the starch structure, extent of amylase digestion and the rate of glucose release by each C and N subunits of SI and MG. Thus, the rate of intestinal starch digestion depends on the structure of the starches, the predigestion by amylase and, importantly, the relative abundance and catalytic properties of the individual subunits of MG and SI. FUNDING SOURCES: Consejo Nacional de Ciencias y Tecnología (CONACyT), Mexico.

The aim of this study was to produce set-type non-dairy yogurt from oat milk pasteurized by thermal (T) and UV-C (coiled-tube type)-assisted thermal (UV–C-T) processes. The yogurts were produced from untreated, T- (63 °C, 30 min) and UV-C-T-treated (10 cycles, 77.67 J/mL, 60 °C) oat milk by lactic acid fermentation and their microbiological, physicochemical, textural and sensorial changes were monitored for 21 days. The reduction in E. coli K-12 was ca. 5 log cfu/mL for both T and UV-C-T treated samples. Yogurts from UV-C-T-treated oat milk had the highest pH (5–6) and the lowest syneresis value during the storage time. L* (60.9 ± 0.1) and b* (4.9 ± 0.1) values of yogurts from UV-C-T-treated oat milk were lower compared to untreated and T-treated oat milk. Yogurts from UV-C-T-treated oat milk had higher hardness (g) and adhesive forces (g) values than the untreated and T-treated yogurts during the storage time. Moreover, there was no significant difference (P

In this study, it was hypothesized that dietary phenolic compounds selectively inhibit the individual C- and N-terminal (Ct, Nt) subunits of the two small intestinal α-glucosidases, maltase-glucoamylase (MGAM) and sucrase-isomaltase (SI), for a modulated glycemic carbohydrate digestion. The inhibition by chlorogenic acid, caffeic acid, gallic acid, (+)-catechin, and (-)-epigallocatechin gallate (EGCG) on individual recombinant human Nt-MGAM and Nt-SI and on mouse Ct-MGAM and Ct-SI was assayed using maltose as the substrate. Inhibition constants, inhibition mechanisms, and IC50 values for each combination of phenolic compound and enzymatic subunit were determined. EGCG and chlorogenic acid were found to be more potent inhibitors for selectively inhibiting the two subunits with highest activity, Ct-MGAM and Ct-SI. All compounds displayed noncompetitive type inhibition. Inhibition of fast-digesting Ct-MGAM and Ct-SI by EGCG and chlorogenic acid could lead to a slow, but complete, digestion of starch for improved glycemic response of starchy foods with potential health benefit.

Diverse natural phenolic compounds show inhibition activity of intestinal α-glucosidases, which may constitute the molecular basis for their ability to control systemic glycemia. Additionally, phenolics can modify mRNA expression for proteins involved in nutritional, metabolic or immune processes. To explore the possibility that phenolics can regulate the mRNA expression, enzymatic activity, and protein synthesis/processing of intestinal Maltase-Glucoamylase (MGAM) and Sucrase-Isomaltase (SI), small intestinal explants from Balb/c mice were cultured for 24 h in the presence or absence of gallic acid, caffeic acid, and (+)-catechin at 0.1, 0.5, and 1 mM. We measured the levels of MGAM and SI mRNA expression by qRT-PCR, maltase and sucrase activities by a standard colorimetric method and the molecular size distribution of MGAM and SI proteins by western blotting. mRNA expression for MGAM was induced by the three phenolic compounds at 0.1 mM. mRNA expression for SI was induced by caffeic and gallic acids, but not by (+)-catechin. Caffeic acid was the most effective inducer of mRNA expression of these enzymes. Total maltase and sucrase activities were not affected by treatment with phenolics. The proportion of high molecular size forms of MGAM was significantly increased by two of the three phenolic compounds, but little effect was observed on SI proteins. Thus, changes in the protein synthesis/processing, affecting the proportions of the different molecular forms of MGAM, may account for the lack of correlation between mRNA expression and enzymatic activity.

Microwave assisted extraction of sour cherry pomace at different conditions were compared with conventional extraction in terms of total phenolic content and antiradical efficiency. Total phenolic content and antiradical efficiency at the optimum conditions (700 W, ethanol-water, 12 min, 20 mL solvent/ g solid) of microwave assisted extraction were 14.14 mg GAE/g sample and 28.32 mg DPPH·/g sample, respectively. Total phenolic content and antiradical efficiency of extracts obtained by conventional extraction were 13.78 mg GAE/g sample and 24.74 mg DPPH·/g sample, respectively. Microwave assisted extraction increased antiradical efficiency and concentration of phenolic acids and shortened extraction time significantly.

Maltase-Glucoamylase (MGAM) and Sucrase-Isomaltase (SI) are α-glucosidases of the membrane of small intestinal enterocytes responsible for the digestion of dietary carbohydrates into glucose and other monosaccharides. MGAM and SI mRNA expression, protein synthesis and catalytic activity of MGAM and SI are found predominantly in enterocytes; however, they are also found in lower amounts in other non-intestinal tissues, notably blood leukocytes and kidney cells. Little information exists on the functions, the mRNA expression, the nature of the respective proteins and catalytic properties of MGAM and SI in non-intestinal tissues. To correlate the transcription, synthesis and activity of these enzymes, we measured the mRNA expression of MGAM and SI; the catalytic activities of maltase, sucrase, and isomaltase; and the presence of the respective proteins in small intestine and other tissues such as spleen, kidney and pancreas of 8 weeks old mice. Small intestine showed the highest level of mRNA expression of M...

Some polyphenols inhibit the activities of the four subunits of intestinal α-glucosidases, maltase-glucoamylase (Mgam) and sucrase-isomaltase (Si). The use of polyphenols as modulators of the rate ...

Some polyphenolic compounds inhibit the intestinal alpha-glucosidases. However, it is not clear how those compounds affect the enzyme activity of the individual C or N terminals subunits of maltase-glucoamylase (Mgam) and sucrase-isomaltase (Si). ObjectiveTo modulate the enzymatic activity of the most active C terminal-Mgam (Ct-Mgam) and C terminal Si (Ct-Si) by selected polyphenols in order to control the glucose release from the starch digestion. MethodsMaltase activities of recombinant Ct-Mgam and Ct-Si subunits were measured by Tris Glucose- Oxidase (TGO) method. The reactions were stopped by TGO and the optical density was measured at 450 nm. ResultsMaltase activity of both enzymes was inhibited. IC50 values were 0.58 and 0.571 mM for caffeic acid, 0.039 and 0.014 mM chlorogenic acid, 0.139 and 0.213 mM for (+)-catechin hydrate, 0.383 and 0.177 mM for gallic acid, 0.041 and 0.014 mM for (−) epigallocatechin gallate for Ct-Si and Ct-Mgam, respectively. ConclusionsThe results indicate that the potencie...