Antioxidant Effects of Glechoma hederacea as a Food Additive

The antioxidant properties of Glechoma hederacea L. (Lamiaceae), of Serbian origin, were studied in respect to its potential use in foodstuffs. Ethanol-water (8:2, v/v) and purified ethyl acetate extracts of the plant were found to possess significant antioxidant activity. Tests were performed on two different substrates, prime steam pork lard and active-carbon-treated edible sunflower oil, using Schaal oven test storage conditions at 60 degrees C. The ethanol-water and purified ethyl acetate extracts of G. hederacea showed strong concentration-dependent antioxidant activity. On the contrary, under the Rancimat method conditions at 120 degrees C, the ethanol-water extract showed significantly stronger antioxidant activity, in comparison with the other tested extracts. All activities were compared with commercial antioxidants, such as BHA and a tocopherol mixture, respectively. For the first time, the activity of the flavonol quercetagetin was determined

The Effect of Partial Root-Zone Drying on Tomato Fruit Growth

Tomato fruit growth and productivity are complex processes depending on the interaction between physiological, genetic and environmental factors. Under current climate conditions of drought and scarce water supply, the challenge is to increase water use efficiency and to sustain tomato yield. Partial root-zone drying technique (PRD) is one of the irrigation methods with the potential to increase the water use efficiency and sustain the yield of many crops including tomato. The aim of presented results was to investigate the effects of PRD on tomato fruit growth, the activity of cell wall-associated peroxidase and ABA content in pericarp of tomato cultivar Ailsa Craig. The experiment was done in controlled conditions and plants under PRD received 70% of water given to full irrigated plants (FI) plants. In PRD irrigation is applied to one half of the root system while the other half dried down and then the treatment was reversed. ABA content in fruit pericarp was measured by ELISA test and cell wall-associated peroxidase activity by a guaiacol test. Fruit growth parameters showed that the maximal growth rate was significantly higher in FI plants than PRD but because the longer period of cell expansion the final diameter of PRD tomato fruits was slightly higher in PRD than in FI fruits. ABA content in tomato pericarp declined during the tomato development until the end of cell growth phase without significant differences between PRD and FI treated plants. The activity of peroxidase was significantly higher in PRD compared to FI. The significantly increase in the activity of enzyme cell wall-associated peroxidase in tomato fruit pericarp under PRD conditions coincided with the end of cell growth and the beginning of the ripening process. These results pointed out that this enzyme may control tomato fruit maturation

Uticaj genotipa sojinog zrna i HTC proizvodnog postupka na aktivnost tripsin inhibitora sojinog mleka

Kunitz inhibitor (KTI) and Bowman-Birk trypsin inhibitor (BBI) are inhibitors of digestive enzymes in raw soybeans. Due to their antinutritive properties in the active state, their inactivation by heat treatment is commonly used. Soymilk is a turbid and stable colloidal solution, obtained by thermal treatment of soybean. In this study soymilk was made on a pilot-plant scale from six soybean cultivars using hydrothermal cooking (HTC) as the production method. This procedure is significantly different from the traditional one. The aim of this investigation was to evaluate the impact of the HTC processing for soymilk production and different soybean genotypes on trypsin inhibitor content and activity. Obtained soymilk contained BBI in trace amounts, in the BBI-polymeric forms. The BBI monomeric forms were not detected. The soymilk of the investigated soybean genotypes had very similar KTI levels (2.34-2.99%). Results have suggested that the soybean genotype does not have substantial effects on the levels of KTI, as well as on the value of residual trypsin inhibitor activity (rTIA). The total content of TI and rTIA showed a strong dependence (r=0.91; p lt 0.05). HTC-soymilk rTIA was lt 20% (7.15-19.89%). These results have indicated that HTC processed soymilk is applicable for human consumption.U sirovoj soji Kunitz-ov (KTI) i Bowman-Birk-ov inhibitor tripsina (BBI) su inhibitori digestivnih enzima. Da bi se poboljšao nutritivni kvalitet hrane od soje, tripsin inhibitori (TI) se inaktiviraju uglavnom termickom obradom. Sojino mleko je mutni i koloidni rastvor, dobijen nakon termičkog tretmana sojinog zrna. U ovoj studiji sojino mleko je napravljeno od šest sorti soje u pilot postrojenju metodom koja uključuje hidrotermičko kuvanje (engl. hydrothermal cooking - HTC). Ovaj postupak se znatno razlikuje od tradicionalnog. Cilj ovog rada je bio da se proceni uticaj HTC postupka za proizvodnju sojinog mleka i različitih genotipova sojinog zrna na sadržaj i aktivnost tripsin inhibitora. Dobij eno sojino mleko je sadržalo BBI u tragovima, u formi BBI-polimera. BBI-monomerne forme nisu detektovane. Sojina mleka od ispitivanih genotipova soje imaju veoma slične sadržaj e KTI (2,34-2,99%). Rezultati su pokazali da genotip sojinog zrna nema značajne efekte na sadžaj KTI, kao i na vrednost rezidualne tripsin inhibitorske aktivnosti (rTIA). Ukupan sadržaj TI i vrednost rTIA je u snažnoj korelaciji (r= 0,91; p lt 0,05). HTC sojina mleka imala su vrednosti za rTIA lt 20% (7,15-19,89%). Ovi rezultati su pokazali da sojina mleka dobijena nakon HTC obrade mogu biti namenjena za ishranu ljudi

Karakterizacija polipeptidnog sastava različitih genotipova soje

The polypeptide composition of soluble proteins of three soya bean genotypes - Nena, ZPS-015 and L91-4042, the latter without Kunitz trypsin inhibitor were studied. SDS-polyacrilamid gel electrophoreses and scanning densitometry of the obtained gels were used to estimate the polypeptide composition. Polypeptide analyses indicated that soybean genotypes express significant differences in both, the protein structure and the protein complex. The lowest content of two major storage proteins, β-conglycinin (7S) and glycinin (11S) was detected in the line without Kunitz trypsin inhibitor (19.49% i 42.13% respectively), the highest β-conglycinin content was in the line ZPS-015 (24.60%) and the glycinine content in the line Nena (45.06%). One polypeptide fraction with a molecular weight close to the molecular weight of γ-conglycinin was noticed only in the soybean genotype L91-4042. The various magnitude in the protein complex was observed in the γ-conglycinin content. The differences in the protein content and the protein structure was also observed in minor protein fractions. The difference in the polypeptide composition of the investigated genotypes was related to previous investigations of soya bean cheese production. The solublity of the soybean protein and the 11S:7S ration has strong influence to the mass and the quality of tofu. Very strong negative correlation exists between the 11S:7S ration and the mass of tofu. Understanding the soya bean genotype protein structure could contribute to characterisation of the existing soya bean lines and to selection of the new soya bean lines with specific functional properties. It is very important for soya bean processing and utilisation.U radu je proučavan polipeptidni sastav rastvorljivih proteina tri genotipa soje - Nena, ZPS-015 i L91-4042. Utvrđivanje polipeptidnog sastava izvršeno je SDS-poliakrilamidnomnom gel elektroforezom i HPLC tehnikom. Polipeptidna analiza je pokazala da sorte soje ispoljavaju značajne genotipske razlike u strukturi proteina i proteinskog kompleksa. Najniži sadržaj dva glavna rezervna proteina soje, β-konglicinina i glicinina detektovan je kod sorte bez Kunitz-ovog tripsin inhibitora (19,49%, odnosno 42,13%) dok je kod sorte ZPS-015 uočen najviši sadržaj β-konglicinin (24,60%), a glicinina je bilo najviše kod genotipa Nena (45.06%). Kod sorte L91-4042 uočena je jedna polipeptidna frakcija čija je molekulska masa bliska γ-konglicininu, a nije prisutna kod ostala dva genotipa. Heterogenost sastava i sadržaja proteinskog kompleksa ispoljen je i kod manje zastupljenih proteinskih frakcija. Okarakterisane genotipske razlike u strukturi proteinskog kompleksa dovedene su u vezu sa ranijim istraživanjima veznim za proizvodnju sojinog sira. Utvrđeno je da na prinos i kvalitet sojinog sira utiče rastvorljivost proteina i odnos glicinin: β konglicinin

Paradajz - model biljka za ispitivanje rastenja i razvića plodova

Because of its specific biochemical and molecular properties and nutrient importance, tomato (Solanum lycopersicum) is an established model to study fruit growth and development. This review paper addresses several aspects of tomato fruit growth and development including its specific phases, control by water regime, cell wall enzymes, plant hormones and metabolic processes.U ovom radu dat je pregled najnovijih rezultata koji su od značaja za razumevanje biohemijskih i fizioloških procesa u toku rastenja plodova. Rezultati su predstavljeni za paradajz kao model biljku za ispitivanje plodova. Iako nisu detaljno predstavljena, genetska istraživanja takođe doprinose poznavanju rastenja i razvića plodova. Prinos paradajza, kao i drugih kultura, u značajnoj meri zavisi od efikasnosti rastenja plodova te su stoga stečena znanja i od praktičnog značaja

The B group vitamins and mineral elements in the selective removal of wheat kernel layers

The objective of this study was to investigate how selective removal of the surface layers of whole wheat grains by abrasive scouring affects the distribution of mineral elements (macronutrients, micronutrients and trace elements) and the B group vitamins (thiamin, riboflavin pyridoxine, pantothenic acid and niacin) in three soft winter wheat varieties (Partizanka, Novosadska rana and Lasta). Although representing technologically different quality classes of wheat, the varieties were not significantly different in the B group vitamin contents, except for pyridoxine. Whole grains of all varieties exhibited very similar scouring behavior in reduction of vitamins: the most intensive investigated regime only slightly, but not significantly reduced the concentration of the B group vitamins. The nutritive value of scoured wheat grains with regard to the B group vitamins was preserved. The investigated minerals were: Na, K, Ca, Mg, N4n, Fe, Cu, Zn, Ni, Cr, Se, Pb and Cd. The concentrations of minerals in scoured wheat grains were significantly reduced, dropping on average to 65% of the initial values for macro and 55% for microelements. The change of concentrations with the duration of applied treatment followed different patterns for different elements. Furthermore, a different pattern of the change for the same element in different wheat varieties was noticed. This might be due either to different mechanical properties of bran and bran layer interfaces or genotypic variability in distribution of elements in wheat grain. Severe reduction in Pb concentrations was achieved leading to improvement of whole-wheat food safety

Influence of different genotypes on trypsin inhibitor levels and activity in soybeans

This study describes the relationship between the two major trypsin inhibitors (TI) in soybean, i.e., the Kunitz (KTI) and Bowman-Birk (BBI) trypsin inhibitors, as well as between them and the corresponding trypsin inhibitor activity (TIA). Twelve investigated soybean genotypes showed significant differences in TI levels and TIA. A very strong positive correlation was found between the levels of KTI and total BBI (r = 0.94, P lt 0.05). No relationship was found between KTI, BBI or total TI and TIA. Based on this data, it appears that the levels of major TI in soybean are related. Understanding the relationship between trypsin inhibitors and their activities could be useful for further improvement of the health impacts of soy proteins

Proteinski sastav tofua korigovanog kvaliteta

Soybeans are an inexpensive, high-quality protein source. Soybeans have long been a staple of the human diet in Asia, especially as tofu, which is prepared from soymilk. In this study, tofu was made using a new production method which includes hydrothermal cooking (HTC) and rennin-pepsin coagulant. The effects of the addition of gallic acid to the slurry during tofu processing were studied. Tofu was made from two soybean genotypes: Lana and Balkan. The observed genotypes are characterized by relatively high content of total proteins in flour, from 45.88% to 48.83%. The prepared tofu samples are characterized by extremely high content of total proteins (52.17% - Lana tofu and 56.08% - Balkan tofu). The presence of gallic acid significantly affects the solubility of tofu protein. The applied modifications of traditional procedure of tofu production significantly improved sensory properties of soybean protein products.Tofu je želirani proteinski proizvod, koji se dobija koagulacijom zagrejanog sojinog mleka. Potrošačima naše populacije ne odgovara aroma 'zelenog zrna', takozvani 'leguminozni miris i ukus', koji se oseća u proizvodima soje pripremljenim na tradicionalni način. Sa namerom poboljšanja arome dobijenih sireva, pripremljen je tofu primenom hidrotermičkog tretmana i enzima za koagulaciju mleka (himozin-pepsin) uz dodatak galne kiselina, koja je jak antiseptik i antioksidant. Zahvaljujući visokom sadržaju ukupnih proteina sojinog semena (45,88-48,83% u obezmašćenom brašnu) i pripremljeni tofu se karakteriše visokim sadržajem ukupnih proteina (52,17% s.m.- Lana tofu i 65,08 % s.m. - Balkan tofu). Postupak dodatka galne kiseline menja sadržaj rastvorljivih proteina (27,48% - Lana tofu i 41,55% - Balkan tofu) koji se značajno razlikuje u odnosu na uzorke bez nje (14,20% - Lana tofu i 28,88% - Balkan tofu). Poliakrilamidnom-gel elektroforezom ekstrakta tofua pripremljenog uz dodatak galne kiseline razdvojen je veći broj komponenata, koje se ne uočavaju na elektroforegramima tofua nemodifikovanog kvaliteta. Gasnohromatografskom analizom isparljivih komponenata tofua registrovan je uglavnom acetaldehid, tako da je postignut cilj ublažavanja legulinoznog mirisa. Poboljšanje senzornih karakteristika potvrđuju i povoljne senzorne ocene koje su dobili uzorci pripremljeni sa galnom kiselinom (3,65 - Lana tofu i 3,87 - Balkan tofu)

Određivanje nutritivne vrednosti pšeničnog hleba sa dodatkom mešavine semena kvinoje, heljde i tikve

The purpose of this research was to blend quinoa (Chenopodium quinoa Willd.), buckwheat (Fagopyrum esculentum Möench) and pumpkin (Cucurbita pepo L.) seed kernels at 40% level with wheat flour and to examine the effect of this blend on nutritional and sensory quality and also energy values of the pan bread. Hydrothermal preparation of these supplements is included. Chemical composition of the investigated materials, wheat bread and supplemented bread, was determined using relevant AOAC methods. Chemical composition of supplemented bread with an increase in protein, oil and crude fiber was superior in comparison with control wheat bread. Sensory properties of supplemented bread such as specific volume, appearance, crust and crumb texture, aroma-odor and color were evaluated and found excellent.Cilj rada je bio da se ispita mogućnost proizvodnje pšeničnog hleba sa dodatkom semena kvinoje, heljde i tikve do nivoa od 40%. Kvinoja (Chenopodium quinoa Willd., familija Amaranthaceae) je pseudocerealija. U ovom radu je korišćena danska sorta KVL 37, gajena u okolini Beograda. Domaća komercijalna semena heljde (Fagopyrum esculentum Möench) i tikve (Cucurbita pepo L.) su nabavljena u lokalnoj radnji zdrave hrane. U ovom radu su prikazani hemijski sastavi prečišćenog semena kvinoje, kao i semena heljde i tikve. Heljda i kvinoja su odabrane zbog toga što ne sadrže gluten, a imaju visok sadržaj kvalitetnih proteina. Očišćeno seme tikve (golica) je odabrano zbog toga što sadrži veliki procenat nutritivno i zdravstveno vrednog ulja i proteina. Analizirane su hemijske i tehnološke osobine mešavine ovih semena i pšeničnog brašna, kao i mogućnost njihove primene u proizvodnji hleba u kalupu. Određen je hemijski sastav i nutritivna energetska vrednost pšeničnog hleba pripremljenog sa dodatkom 15% semena kvinoje, 15% semena heljde i 10% golice. U odnosu na kontrolni pšenični hleb, obogaćeni hleb je sadržao 6% više proteina, 3,8% više ulja i oko 5% više sirovih vlakana. Sadržaj skroba u obogaćenom hlebu je bio niži za oko 8%. Energetska vrednost obogaćenog hleba je porasla za oko 150 kJ/100 g. Obogaćeni hleb je imao dobru specifičnu zapreminu i odlične senzorne osobine. Pokazano je da je ispitivana mešavina pšeničnog brašna i odabranih semena pogodna za proizvodnju hleba u kalupu, povećane nutritivne vrednosti

Promene polipeptidne strukture sojinog proteinskog izolata pri termičkoj inaktivaciji antinutritivnih komponenti

The change of polypeptide composition of soybean isolates, prepared from samples treated by autoclaving in the aim of trypsin inhibitors inactivation (0.5 bar; 5,10 and 15 min.) was investigated. By densitometric analysis of SDS-PAGE-gels, the composition of soybean isolated protein was determined. According to our results, glycinin showed the highest content among proteins of soybean isolates. Depending on duration of soybeans heating, the percentage of glycinin in resulting isolate was 47.14-53.08%. High content of acidic (30.02-30.98%) and basic (15.12-18.24%) polypeptides of glycinin was registered. High content of a-subunit of P-conlycinin was determined (11.49-8.99%). The presence of Bowman-Birk TI as well as lypoxigenase, was not registered in any of protein isolates.Cilj ovog rada bio je da se ispita uticaj nadpritiska 0,5 bara, radne temperature 96°C u trajanju od 5,10 i 15 minuta u autoklavu na promene polipeptidne strukture dobijenih proteinskih Izolata iz lomljenog sojinog zrna. Potvrđena je termostabilnost molekulaglicinina (47,14-53,08%), i manja stabilnost B-konglicinina (15,31-25,45%). Denzitomelrijska analiza SDS-elektroforegrama ukazuje na izraženu termostabilnost kiselih A1,2,4(27,50-26,31%) i baznih B1,2,3,4(18,24-15,12%) polipeptlda glicinina. Sadržaj a-polipeptida fikonglicinina pokazuje linearnu zavisnost od trajanja primenjenih tretmana (10,92-8,99%). Nakon ovih tretmana zapažena je smanjena tripsininhibitorska aktivnost (TIA), pri čemu je nosilac TIA Kunitz-ov TI (5,00-8,80%), dok je Bowman-Birk-ov inhibitor registrovan samo kod izolata iz netretiranog lomljenog sojinog zrna (3,92%)