QUALITY ASSESSMENT OF ORGANIC AND CONVENTIONAL AGRICULTURAL PRODUCTION OF PLANT PRODUCTS Justina Zykevičiūtė-Laugks Department of Forestry and Ecology, Aleksandras Stulginskis University, Studentu 11, Kaunas, Lithuania

What is benefit of organic? Organic Food is Healthy and Safe Organic Food Keeps Our Water Clean Organic Food Helps Protect Animals Organic Food Results in Less Soil Erosion Organic Food Offers Outstanding Flavor Organic Food is Becoming More Affordable Non-organic food often contains harmful hormones and pesticides. Pesticides are poisonous - by nature they're designed to kill. Pesticides can cause neurological problems, cancer, other skin problems. Logic says don't eat poison, right? Why not go organic and avoid pesticides?

The aim of the investigation Evaluate and approve various new methods of comparison for quality analysis of organic and conventional agricultural plant production. Studies should compare a variety of essential nutritional components that could therefore have an impact on health and the environment where they were produced. Biochemical composition Biocrystalisation and Hyperspectrical scan (Hollistic methods) Biocrystalisation and Hyperspectrical scan (Hollistic methods) Spectrophotometric analysis Electrochemical analysis

Quality parameters of carrot Carrot quality is determined by their biochemical composition. One of the main indicators is the amount of carotene in them. The organic farming system differs fundamentally in soil fertility, weed, pest and disease management, and makes higher demands on product quality and yield stability than conventional farming. The consumer quality can include such diverse attributes as vitamin content, absence of antimetabolic compounds, flavour, texture, colour, appearance and convenience.

Quality inner parameters for carrots

ANTIOXIDANT COMPONENTS IN CARROTS Carotenoids beta- carotene and tocopherol vitamins C and E phenolic compounds flavonoids endogenous metabolites dietary glutathione derivatives chlorogenic acid from 42.2% to 61.8% of total phenolic compounds [1] hydroxycinnamic acids [1] source: Wang, H., Hu, X., Chem, F., Wu, J., Zhang, Z., Liao, X. & Wang, Z. (2006), “Kinetics analysis of nonenzymatic browning in carrot juice concentrate during storage”, European, Food. Research & Technology, 223,

ANTIOXIDANT FEATURES AND ANALYSIS METHODS OF THE PHENOLIC COMPOUNDS Oxidation mechanism –Free radicals – oxidants Antioxidant features –Antioxidants in carrots Analysis methods –Spectrophotometric analysis to determine phenolic compounds and antioxidant activity General flavonoid chemical structure

FREE RADICAL It is an unbound compound (i.e., free) having one or more unpaired electrons

Sources of free radicals

Antioxidant features

Antioxidant Defense Processes Prevention—Balance between oxidative load and antioxidant function – Vitamin E, ascorbic acid, beta-carotene Interception—Local antioxidant levels – Vitamin E, glutathione, superoxide dismutase Repair—Mostly enzymatic – DNA repair system, reductases

Antioxidant Defense Processes Vitamin E−Protects lipids from the cell membrane bilayer from attack by free radicals Vitamin C−Quenches 1 in cytosol−Recycles vitamin E after it captures free radicals O2 Carotenoids−Beta-carotene quenches 1 ; may also inhibit free-radical-generating reactions−Autoregenerate with release of thermal energy O2

Objectives I.Effect of drying method: sliced and pressed carrots drying in fruit desicator under +40 ºC ; sliced carrots freeze-dried under vacuum condition by -72 ºC up to 72h. II.Effect of extraction with different solvent ratio (75% and 100% methanol). III.Spectrophotometric analysis: 1. Determination of total amount of phenolic compounds (expressed in galic acid equivalents mg/g for dry material according to the Folin-Ciocalteu colorimetric method ) 2. Determination of antioxidant activity (based on DPPH bleaching reaction slightly modified method of Brand-Williams et al.) The aim of research The determination of the total antioxidant activity and phenolic compounds of carrots extracts.

Methods of sample preparation Fresh sliced carrots Fresh pressed carrots Fresh sliced carrots freeze-dried under vacuum condition by -72 ºC up to 72h dried by +40 ºC in fruit desicator

Maceration of sample 0.25g and 0.5 g carrot stock and + 10ml 75% and 100% of MeOH shaking for 1 h filtering 75% or 100% of Methanol extract

Equipment: T70 UV-VIS spektrophotometer Spektrophotometrical analysis Diode matrix Prism Gap ray Sample Source UV detection at 760nm for phenolic compounds and 515nm for antioxidant activity

Spectrophotometry Follin-Cio Calteu reagent is used for Analysis of total amount of phenolic compounds and measured with 760nm. Expressed in gallic acid equivalents (mg/g) in dry material. DPPH radical scavenging activity is determined to measure the changes in colour (from deep-violet to light-yellow) at 515nm. (Brand Williams method)

Antioxidant activity Results Fig. 1. DPPH radical scavenger activity %. Samples: raw methanolic extract obtained using 0.5 g and 0,25g of dry carrot material and 10 ml 75% and 100% of methanol

Antioxidant activity and phenolic compounds Fig. 2. Content of phenolic compounds, using gallic acid as a standard and expressed as mg/g gallic acid equivalent (GAE) in dry carrots material. (Folin-Ciocalteu method). Antioxidant activity % as in Fig.1.

Time efect for antioxidant activity of 75% methanol extracts Fig. 3. The time influence on antioxidant activity dynamic (by 75% methanolic extracts).Significant time effect was until 30min p<0,05.

Time efect for antioxidant activity of 100% methanol extracts Fig. 4. Dynamic of AOX activity in 100% extracts. Mostly time effect was significant by sliced 0.5g and pressed0.5g.

Antioxidant activity was determined using DPPH radicals. Influence of drying method (sliced and dried in desicator +40 ºC or lyophilised under vacuum condition (freeze- dried) by –72 ºC) was not significant p>0.05, but solvent concentration showed significant correlation with antioxidant activity and phenolic compound (p<0.05). Drying methods were significant for phenolic compounds (p<0.05). Conclusions (I)

Among the weight of raw dryed material and the various ratio of methanolic extracts, significantly the best antioxidant activity shows 0.5g and 75% of sliced desiccated, freeze – dried and pressed desiccated samples. For the next step of sample preparation extraction with 75% of solvent and 0.5 g of dry material of carrots would be preferred. Conclusions (II)

Hyperspectrical analysis: jRw&url=http%3A%2F%2Fwww.photonics.com%2FArticle.aspx%3FAID%3D53223&ei=sr- VUZ7xH8SQtQaHv4G4Dw&bvm=bv ,d.bGE&psig=AFQjCNGLwDHU8REUkcFGe2xstAsZhiQGmw&ust= Determination of the proper operator on different tissues could help to analyze and model drying process and to control storage. Hyperspectral data of different carrot cultivars were tested under different storage conditions and bounded with other parameters of carrots, like pH, redox potential, specific eletrical conductivity, amount of nitrates. Recommendations for future research

DPPH + AH = DPPH – H + A DPPH + R = DPPH – H HPLC – DPPH radical scavenging method Buffered synthetic free radical 2,2-diphenyl- 1-picrylhydrazil DPPH radical solution is bleached when reacts with antioxidants HPLC–DPPH reaction detection setup

HPLC-DPPH Antioxidant activity EpikatechinLiuteolinApigeninPinocemrbin %RE0,001660,001810,008480,00679 Sample:Species diaphoretica Nr. 3 Inhibition of DPPH free radical is calculated from Rutin eqvivalent equition y = 3855,6x

Acknowledgements: Carrot samples provided by „Babtai Horticulture institute“ are ackowledged.