Onosma riedliana Binzet & Orcan, a traditionally used plant species, has been explored for its therapeutic potential in this study. The work presented here is the first report on the phenolic profile and biological activity of this species. Three extracts of varying polarity were prepared, with the methanolic extract containing the highest phenolic content (97.62 ± 0.20 mgGAE/g). Key phenolic compounds identified included pinoresinol, hesperidin, 4-hydroxybenzoic acid, and p-coumaric acid. The methanolic extract exhibited exceptional antioxidant properties, rivaling Trolox as a positive control, primarily attributed to hesperidin and luteolin. Moreover, the ethyl acetate extract demonstrated remarkable inhibition of cholinesterase and tyrosinase enzymes, while the methanolic extract displayed potent activity against carbohydrate hydrolytic enzymes, α-amylase and α-glucosidase. Again, phenolic compounds were shown to be responsible for the inhibition of cholinesterases and tyrosinase, but not for α-amylase and α-glucosidase. These findings underscore Onosma riedliana's potential for incorporation into diverse pharmaceutical formulations, given its multifaceted bioactivity.
Production of amylases by fungi under solid-state fermentation is considered the best methodology for commercial scaling that addresses the ever-escalating needs of the worldwide enzyme market. Here response surface methodology (RSM) was used for the optimization of process variables for α-amylase enzyme production from Trichoderma virens using watermelon rinds (WMR) under solid-state fermentation (SSF). The statistical model included four variables, each detected at two levels, followed by model development with partial purification and characterization of α-amylase. The partially purified α-amylase was characterized with regard to optimum pH, temperature, kinetic constant, and substrate specificity. The results indicated that both pH and moisture content had a significant effect (P < 0.05) on α-amylase production (880 U/g) under optimized process conditions at a 3-day incubation time, moisture content of 50%, 30 °C, and pH 6.98. Statistical optimization using RSM showed R2 values of 0.9934, demonstrating the validity of the model. Five α-amylases were separated by using DEAE-Sepharose and characterized with a wide range of optimized pH values (pH 4.5-9.0), temperature optima (40-60 °C), low Km values (2.27-3.3 mg/mL), and high substrate specificity toward large substrates. In conclusion, this study presents an efficient and green approach for utilization of agro-waste for production of the valuable α-amylase enzyme using RSM under SSF. RSM was particularly beneficial for the optimization and analysis of the effective process parameters.
Combining high-carbohydrate food with polyphenol-rich food is a possible way of producing slowly digestible starch with beneficial health properties. In Japan, non-glutinous and glutinous rice are cooked with adzuki bean and the colour of the cooked rice is pale red. In this article, we show that (1) the red colour of rice could be attributed to the oxidation of adzuki bean procyanidins, (2) pancreatin-induced starch digestion of the red-coloured non-glutinous rice was slower than white rice and (3) the digestion of amylose and potato starch but not amylopectin became slower by heating with procyanidin B2. Furthermore, the rate of starch digestion of red-coloured rice was not affected by nitrite treatment under simulated gastric conditions. The above results show that procyanidins could bind to amylose independent of the starch source by heating and could suppress starch digestion by α-amylase in the intestine.
- MeSH
- alfa-amylasy MeSH
- amylopektin metabolismus MeSH
- amylosa metabolismus MeSH
- biflavonoidy MeSH
- katechin MeSH
- lidé MeSH
- pankreatin metabolismus MeSH
- proantokyanidiny metabolismus MeSH
- rýže (rod) * MeSH
- trávení * MeSH
- vaření MeSH
- vigna * MeSH
- vysoká teplota MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Japonsko MeSH
S rozvojom civilizačných chorôb, ako je diabetes mellitus, metabolický syndróm, prípadne obezita, rastie aj úsilie nachádzať nové liečivá predovšetkým z prírodných zdrojov. Patria medzi ne aj inhibítory α-amylázy, enzýmu, ktorý v tele zdravého človeka štiepi polysacharidy na jednoduchšie cukry. Vzhľadom k tomu, že toto štiepenie ovplyvňuje glykémiu, ktorú je snaha terapeuticky meniť, vzrastá aj záujem o tieto látky. Tento prehľadový článok mapuje druhy inhibítorov amylázy vrátane ich prírodných zdrojov.
Development of civilization diseases such as diabetes mellitus, metabolic syndrome or obesity, enforces the increasing effort to find new drugs, especially from natural sources. These include α-amylase inhibitors, which break down polysacharides into simple sugars in the body of a healthy person. As this cleavage affects the level of blood sugar, which is sought to be therapeutically influenced, there is a growing interest in these substances. This review maps the types of amylase inhibitors, including their natural resources.
- Klíčová slova
- rostlinné inhibítory, štěpení škrobu,
- MeSH
- alfa-amylasy antagonisté a inhibitory terapeutické užití MeSH
- amylasy * antagonisté a inhibitory terapeutické užití MeSH
- lidé MeSH
- škrob metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- přehledy MeSH
The diet rich in fruits and vegetables reduces the risk of metabolic syndrome, including diabetes development by various mechanisms of action, mainly due to the presence of polyphenolic compounds. Extracts from different conifer species are known to be a rich source of various polyphenols. In the present study we elucidated the in vitro mechanism of anti-diabetic activity of silver fir (Abies alba) wood and bark extracts and compared their activity to non-coniferous sweet chestnut wood extract and standardized maritime pine bark extract. Extracts and lignans were tested for their inhibitory activity of enzymes involved in the regulation of blood glucose in vitro. The ability of extracts to protect against oxidative stress in high glucose environment was tested on mouse myoblast cell line. Silver fir wood and bark extracts were shown to be effective inhibitors of α-glucosidase, α-amylase and dipeptidyl peptidase 4, three enzymes involved in the regulation of blood glucose levels. Coniferous extracts also showed protection against oxidative stress generated in high glucose environment. Lignans, particularly pinoresinol diglucoside, isolariciresinol and secolariciresinol were shown to be important contributors of antihyperglycemic activity through inhibition of dipeptidyl peptidase 4. This corroborates previously published in vivo results on blood glucose level obtained with silver fir wood extract and supports the use of silver fir wood and bark extracts as food supplements or functional foods in borderline diabetes.
- MeSH
- alfa-amylasy antagonisté a inhibitory MeSH
- alfa-glukosidasy metabolismus MeSH
- buněčné linie MeSH
- dipeptidylpeptidasa 4 metabolismus MeSH
- dřevo chemie MeSH
- hypoglykemika izolace a purifikace farmakologie MeSH
- inhibitory dipeptidylpeptidasy 4 izolace a purifikace farmakologie MeSH
- inhibitory glykosidových hydrolas izolace a purifikace farmakologie MeSH
- jedle chemie MeSH
- krevní glukóza účinky léků MeSH
- kůra rostlin chemie MeSH
- lidé MeSH
- myši MeSH
- oxidační stres účinky léků MeSH
- rostlinné extrakty izolace a purifikace farmakologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Pancreatic α-amylase plays an important role in dietary starch hydrolysis in the small intestine and participates in enhanced glucose concentration after meals. It seems to be a problem for diabetic patients, who suffer from longer postprandial hyperglycemia after meal consumption than healthy people. There are commercially available drugs that inhibit α-amylase and thus reduce the postprandial hyperglycemia effect. However, these drugs may cause severe side effects. Conversely, some naturally occurring flavonoids were suggested to have an α-amylase-inhibiting effect without any side effects. There had been no rapid, undemanding method in terms of sample and reagent preparation that would enable screening of many potential inhibitors. Therefore, we developed an online capillary electrophoresis method to monitor α-amylase activity in the presence of an inhibitor. Each reaction constituent was introduced separately, directly into a capillary where the reagents were mixed by diffusion, which resulted in a 5-min analysis including conditioning of the capillary. We applied the method to test the inhibitory effect of flavonoid standards and their mixture and we investigated the inhibitory effect of ethanolic extract from Betula pendula bark. The developed method presents a faster and less expensive alternative to previously described offline methods. Graphical abstract Online CE screening of α-amylase inhibitors.
- MeSH
- alfa-amylasy krev MeSH
- diabetes mellitus 2. typu * farmakoterapie komplikace MeSH
- dospělí MeSH
- dvojitá slepá metoda MeSH
- hypoglykemika aplikace a dávkování terapeutické užití MeSH
- lidé středního věku MeSH
- lidé MeSH
- lipasa krev MeSH
- liraglutid * aplikace a dávkování terapeutické užití MeSH
- metformin aplikace a dávkování terapeutické užití MeSH
- nadváha komplikace MeSH
- pankreas * metabolismus účinky léků MeSH
- randomizované kontrolované studie jako téma MeSH
- receptor pro glukagonu podobný peptid 1 agonisté metabolismus MeSH
- senioři MeSH
- sitagliptin fosfát * aplikace a dávkování terapeutické užití MeSH
- trypsinogen krev moč MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
This study examined the biochemical characteristics of α-amylase and hormonal (adipokinetic hormone: AKH) stimulation of α-amylase activity in the cockroach (Periplaneta americana) midgut. We applied two AKHs in vivo and in vitro, then measured resultant amylase activity and gene expression, as well as the expression of AKH receptor (AKHR). The results revealed that optimal amylase activity is characterized by the following: pH: 5.7, temperature: 38.4 °C, Km (Michaelis-Menten constant): 2.54 mg starch/mL, and Vmax (maximum reaction velocity): 0.185 μmol maltose/mL/min. In vivo application of AKHs resulted in significant increase of amylase activity: by two-fold in the gastric caeca and 4-7 fold in the rest of the midgut. In vitro experiments supported results seen in vivo: a 24-h incubation with the hormones resulted in the increase of amylase activity by 1.4 times in the caeca and 4-9 times in the midgut. Further, gene expression analyses reveal that AKHR is expressed in both the caeca and the rest of the midgut, although expression levels in the former were 23 times higher than levels in the latter. A similar pattern was found for the amylase (AMY) gene. Hormonal treatment did not affect the expression of either gene. This study is the first to provide evidence indicating direct AKH stimulation of digestive enzyme activity in the insect midgut, supported by specific AKHR gene expression in this organ.
- MeSH
- alfa-amylasy metabolismus MeSH
- gastrointestinální trakt účinky léků enzymologie MeSH
- hmyzí hormony metabolismus farmakologie MeSH
- kyselina pyrrolidonkarboxylová analogy a deriváty metabolismus farmakologie MeSH
- oligopeptidy metabolismus farmakologie MeSH
- Periplaneta účinky léků enzymologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In germinating seeds under unfavorable environmental conditions, the mobilization of stores in the cotyledons is delayed, which may result in a different modulation of carbohydrates balance and a decrease in seedling vigor. Tall fescue (Festuca arundinacea Schreb.) caryopses grown at 4°C in the dark for an extended period in complete absence of nutrients, showed an unexpected ability to survive. Seedlings grown at 4°C for 210 days were morphologically identical to seedlings grown at 23°C for 21 days. After 400 days, seedlings grown at 4°C were able to differentiate plastids to chloroplast in just few days once transferred to the light and 23°C. Tall fescue exposed to prolonged period at 4°C showed marked anatomical changes: cell wall thickening, undifferentiated plastids, more root hairs and less xylem lignification. Physiological modifications were also observed, in particular related to sugar content, GA and ABA levels and amylolytic enzymes pattern. The phytohormones profiles exhibited at 4 and 23°C were comparable when normalized to the respective physiological states. Both the onset and the completion of germination were linked to GA and ABA levels, as well as to the ratio between these two hormones. All plants showed a sharp decline in carbohydrate content, with a consequent onset of gradual sugar starvation. This explained the slowed then full arrest in growth under both treatment regimes. The analysis of amylolytic activity showed that Ca2+ played a central role in the stabilization of several isoforms. Overall, convergence of starvation and hormone signals meet in crosstalk to regulate germination, growth and development in tall fescue.
- MeSH
- alfa-amylasy metabolismus MeSH
- buněčná stěna metabolismus fyziologie MeSH
- časové faktory MeSH
- Festuca metabolismus fyziologie MeSH
- fyziologická adaptace fyziologie účinky záření MeSH
- fyziologický stres fyziologie MeSH
- gibereliny metabolismus MeSH
- kořeny rostlin metabolismus fyziologie MeSH
- kotyledon metabolismus fyziologie MeSH
- kyselina abscisová metabolismus MeSH
- lignin metabolismus MeSH
- nízká teplota MeSH
- rostlinné proteiny metabolismus MeSH
- sacharidy analýza MeSH
- semenáček fyziologie MeSH
- světlo MeSH
- tma MeSH
- vápník metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
