Tag Archives: antiradical activity

1293-1303 Z. Shakiryanova, R. Khegay, U. Gayibov, A. Saparbekova, Z. Konarbayeva, A. Latif and O. Smirnova
Isolation and study of a bioactive extract enriched with anthocyanin from red grape pomace (Cabernet Sauvignon)
Abstract |
Full text PDF (887 KB)

Isolation and study of a bioactive extract enriched with anthocyanin from red grape pomace (Cabernet Sauvignon)

Z. Shakiryanova¹, R. Khegay¹, U. Gayibov², A. Saparbekova¹, Z. Konarbayeva¹, A. Latif¹ and O. Smirnova³

¹M.Auezov South Kazakhstan University, Faculty of Chemical Engineering,
and Biotechnology Department of Biotechnology, Tauke khan avenue 5, KZ160000 Shymkent, Kazakhstan
²Academy of Sciences of Uzbekistan, Institute of Bioorganic Chemistry,
M. Ulugbek street 83, UZ100125 Tashkent, Uzbekistan
³HSE University, HSE Campus in St. Petersburg, School of Arts and Humanities, Department of Foreign Languages, 3 Kantemirovskaya Str., RU194100 Saint Petersburg, Russia
*Correspondence: zulya_sun@mail.ru

Abstract:

Grape pomace is a natural product rich in dietary fibers, polyphenols and anthocyanidins. By their chemical composition, secondary products from grape processing are valuable raw materials for obtaining a variety of new products. Recently, in food biotechnology, fermented and unfermented grape pomace have undergone a deeper study of the role of additives in dry powders or extracts. The quality and biological value of natural food products are determined by their chemical composition and a whole complex of integral organoleptic properties that depend on this composition. Natural anthocyanin dyes not only give color to vegetable raw materials, but also have a well-known physiological activity, in particular, coloring and antioxidant. Purified natural dyes have recently been increasingly used to improve the consumer properties of food products, in biologically active additives, in pharmaceutical preparations for the treatment and prevention of various diseases. At the same time, the composition of anthocyanins, even for the same variety of plant raw materials, is complex and variable; it depends on climatic conditions, on the maturity of berries, root crops, and the quality of agricultural work. Anthocyanins easily undergo a number of transformations depending on the conditions of extraction and analysis.

The originality and novelty of the isolation and production of biologically active extracts with antiradical properties from by-products of local wineries in ecologically safe areas of southern Kazakhstan lies in the fact that natural environmental conditions: high temperatures and low humidity which contribute to the formation of biologically active substances with increased concentrations. Current research was aimed at the deep study of extracts from grape pomace rich – anthocyanins.

Red grape pomaces of Vitis vinifera L. Cabernet Sauvignon were extracted using a solvent-based (SE) method with concentrations of 70% v/v and solid/liquid ratios of 1:10, followed by incubation at three different temperatures of 30 °C, 40 °C, and 50 °C for 1 h, 2 h, 3 h, and 4 h. All solvent extracts showed higher amounts of anthocyanin pigments. The maximum yield was obtained by using the optimal time of extraction (2 h at 50 °C), with the highest total anthocyanin recovery obtained by means of 70% ethanol. The anti-radical and toxic effects of the obtained extract (anthocyanin) were studied.

Key words:

, , , , ,




1860–1872 A. Ramata-Stunda, V. Valkovska, M. Borodušķis, D. Livkiša, E. Kaktiņa, B. Silamiķele, A. Borodušķe, A. Pentjušs and N. Rostoks
Development of metabolic engineering approaches to regulate the content of total phenolics, antiradical activity and organic acids in callus cultures of the highbush blueberry (Vaccinium corymbosum L.)
Abstract |
Full text PDF (478 KB)

Development of metabolic engineering approaches to regulate the content of total phenolics, antiradical activity and organic acids in callus cultures of the highbush blueberry (Vaccinium corymbosum L.)

A. Ramata-Stunda¹, V. Valkovska², M. Borodušķis¹, D. Livkiša¹, E. Kaktiņa¹, B. Silamiķele¹, A. Borodušķe¹, A. Pentjušs³ and N. Rostoks¹*

¹Faculty of Biology, University of Latvia, Jelgavas street 1, LV-1004 Riga, Latvia
²Faculty of Chemistry, University of Latvia, Jelgavas street 1, LV-1004 Riga, Latvia
³Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas street 1, LV-1004 Riga, Latvia
*Correspondence: nils.rostoks@lu.lv

Abstract:

Blueberry (Vaccinium corymbosum L.) is increasingly cultivated to produce high quality berries for consumption and potential applications in medicine, nutrition and as industrial precursors. Seasonal availability sets limitations on chemical compound isolation from cultivated plants. Biotechnological solutions, such as tissue cultures and metabolic engineering, can provide sufficient amounts of plant material with reasonably high metabolite levels, which may be adjusted by different strategies. Here, we describe our approach to modifying total phenolic content (TPC), antiradical activity (ARA) and amounts of selected organic acids in in vitro cultures of two varieties of V. corymbosum by varying the growth media. TPC, ARA and acid levels were determined in mature leaves of field-grown plants and in stable callus cultures derived from leaves of varieties ‘Bluecrop’ and ‘Duke’ grown on Murashige-Skoog (MS) and Woody plant (WP) media supplemented with varying concentrations and combinations of different plant growth hormones. TPC varied from 83 mg g-1 dry weight (DW) to 142 mg g-1 DW in leaves of ‘Bluecrop’ and ‘Duke’, respectively, and correlated with their ARA with ‘Duke’ at the lead. For callus cultures the highest ARA, as well as the highest TPC of 94 mg g-1 DW was observed in ‘Bluecrop’ grown on WP medium with 2,4-dichlorophenoxyacetic acid (2,4-D). High level of quinic acid was found in the mature leaves of all tested varieties, while callus cultures exhibited relative increase in amounts of malic, succinic and citric acids instead. Oxalic acid was found only in callus cultures.

Key words:

, , , , ,




1442–1450 I. Shepelev, R. Galoburda and T. Rakcejeva
Changes in the total phenol content in the industrial potato peel wastes during the storage
Abstract |
Full text PDF (270 KB)

Changes in the total phenol content in the industrial potato peel wastes during the storage

I. Shepelev*, R. Galoburda and T. Rakcejeva

Latvia University of Agriculture, Faculty of Food Technology, St. Liela 2, LV-3001 Jelgava, Latvia
*Correspondence: igor_shepelev@inbox.lv

Abstract:

 As a zero value by-product from the economic point of view, potato (Solanum tuberosum L.) peel is a good source of phenols. As a manufacturing waste, potato peels are stored at the uncontrolled conditions and are exposed to the fermentative, oxidative, and microbial degradation. The aim of the present study was to determine the phenol degradation dynamics in the stored peels so the maximum storage time could be defined to achieve the efficient phenol extraction. Three different types of samples were prepared by abrasion peeling method and stored at room temperature, in open air, up to six days. Phenol extracts were obtained using ethanol-based solvent. Total phenol content was expressed as a gallic acid equivalent; antiradical activity was measured using the 2,2-diphenyl-1-picrylhydrazylradical. Results revealed that total phenols during the storage are more stable in the larger peel samples that can be stored up to two days without significant changes in the total polyphenol content and antiradical activity. Finely shredded peel demonstrated significant decrease in the total phenol amount and in the antiradical activity already on the second day of the storage. This fact indicated that in the finely shredded peel samples phenols are easily accessible to the oxidative and fermentative processes. It is possible, that after peeling there were big amounts of chlorogenic acid in the samples. When total amount of polyphenols decreased, chlorogenic acid degraded and caffeic acid was released in sufficient amount to hold antiradical activity of the extract on the high level.

Key words:

, ,




969-978 L. Klavina
A study on bryophyte chemical composition–search for new applications
Abstract |
Full text PDF (374 KB)

A study on bryophyte chemical composition–search for new applications

L. Klavina

University of Latvia, Department of Environmental Science, Raina Blvd. 19, Riga, LV-1586, Latvia; e-mail: laura.klavina@lu.lv

Abstract:

Bryophytes are the taxonomic group in the plant kingdom represented with about 25’000 species. They contain a high number of biologically active compounds; however their use as a food source is negligible. The aim of this paper is to evaluate bryophyte chemical composition and new possible applications. In order to evaluate bryophyte potential usage as a raw food material, bryophyte basic chemical content and the secondary metabolite profile was determined. To obtain best results bryophyte secondary metabolite extraction options has been studied. Couple of extraction methods were used (conventional, ultrasound, microwave, supercritical CO2 extraction etc.) and different solvents (ethanol, water etc.). A total concentration of polyphenols and substances determining free radical scavenging activity has been determined. The extracts obtained from bryophytes have remarkable antioxidant activity, the extent of which depends on the extraction conditions and bryophyte species. Comparison of five extraction methods and several solvents indicates that microwave assisted extraction and supercritical CO2 extraction is the most promising approach to obtain highest yields of extractives.

Key words:

, , , ,