Polyphenols and inhibitory effects of crude and purified extracts from tomato varieties on the formation of advanced glycation end products and the activity of angiotensin-converting and acetylcholinesterase enzymes.

The study analyzed the inhibitory effects (IC50) of crude and purified extracts from Maliniak, Cerise, Black Prince and Lima tomatoes on the formation of advanced glycation end products (AGEs), the activity of angiotensin-converting (ACE) and acetylcholinesterase (AChE) enzymes. Polyphenol composition (LC-MS) and antioxidant capacity (PCL, FRAP) were measured. The purified extracts of Black Prince tomatoes were the most potent inhibitors of AGEs in BSA-GLU (7.20mg/mL) and BSA-MGO (9.53mg/mL) models. The purified extracts of Cerise and Black Prince tomatoes had the highest ACE (0.50-0.44mg/mL) and AChE (7.93-5.83mg/mL) inhibitory activity. Cerise variety showed the highest polyphenol concentrations in crude (488.93µg/g DM) and purified (8394.99µg/g DM) extracts. The highest PCLACW and FRAP values were found for Cerise purified extracts (71.83 and 87.78µmol Trolox/g DM). Caffeic acid, caffeoyl-glucose, linocaffein, glucosyl-coumarate, vanillic acid, rutin and TPI values were significantly correlated with BSA-MGO, anti-ACE, anti-AChE and PCLACW parameters.

Functionality of porous starch obtained by amylase or amyloglucosidase treatments.

Porous starch is attracting very much attention for its absorption and shielding ability in many food applications. The effect of two different enzymes, fungal α-amylase (AM) or amyloglucosidase (AMG), on corn starch at sub-gelatinization temperature was studied as an alternative to obtain porous starch. Biochemical features, thermal and structural analyses of treated starches were studied. Microscopic analysis of the granules confirmed the enzymatic modification of the starches obtaining porous structures with more agglomerates in the case of AMG treated starches. Several changes in thermal properties and hydrolysis kinetics were observed in enzymatically modified starches. Hydration properties were significantly affected by enzymatic modification being greater influenced by AMG activity, and the opposite trend was observed in the pasting properties. Overall, results showed that enzymatic modification at sub-gelatinization temperatures really offer an attractive alternative for obtaining porous starch granules to be used in a variety of foods applications.

Effect of gamma-radiation and microwave heating on endosperm microstructure in relation to some technological properties of wheat grain.

Grains of the Polish winter wheat variety Begra were subject to gamma-radiation (60Co) within the dose range of 0.05-10 kGy and microwave treatment from 15 to 180 s, the latter resulting in a bulk grain temperature ranging from 28 to 98 degrees C. Both processes were responsible for marked structural changes of wheat kernel endosperm and were pronounced with increasing dose of ionizing radiation or with prolonged time of microwave treatment. Endosperm microstructures of wheat kernels treated with gamma-radiation ranging from 0.05 to 0.5 kGy did not differ from that of untreated ones. Only some changes in the structure of starch granules and proteins were observed at doses of 1, 5 and 10 kGy. Simultaneously at the doses of 5 and 10 kGy a statistically significant decrease of falling number, sodium dodecyl sulfate (SDS) sedimentation values, dough stability and energy were observed, while dough weakening progressed. Microwave treatment longer than 90 s caused marked changes in kernel endosperm structure. Some changes of proteins caused by denaturation created visible fibrils as well as high swelling and deformation of starch granules. This was followed by an increase in the falling number value, decrease in the estimated results of SDS sedimentation test, lowering of the percent of gluten washed out and of the dough energy, respectively. Also a significant decrease in bread quality expressed by volume and score was observed with increasing time of exposure to microwave.