## 1 Introduction  
Recently, there has been a rising interest in the identification, quantification and extraction of plant compounds with a beneficial effect on human health that can be utilized in the food, cosmetic or para-pharmaceutical industry. The identification of these compounds can generate new food supplements or food products [1]. Resveratrol (3,5,4\({}^{\prime}\)-trihydroxystilbene) is a natural phenol compound which is a part of the stilbene family [2] and it is synthesized by plants as a result of exposure to various stressful factors, such as exposure to ultraviolet radiation [3], damage and fungal parasites, etc. [4]. This compound offers potential positive therapeutic effects on slowing down the aging process [5], antioxidant effect against free radicals [6], anti-aging effects on skin by suppressing the responsible enzymes, antibacterial effects [7], antifungal effects [8], anti-inflammatory activity [9], anti-carcinogenic effect, cardio protective effects [10], protection against diseases of the nervous system [11] and beneficial effects on the symptoms of diabetes [7]. Due to the positive impact of resveratrol intake to the human body confirmed by research, resveratrol supplements have been commercialized since 2012 [12]. This antioxidant is further used in the cosmetic [13] and food industries, with the permission of the Commission Implementing Decision (EU) 2016/1190 for the use of resveratrol as a new food ingredient in the European Union [14]. In the food industry, resveratrol started to be used in many areas, such as in manufacturing edible films enriched with this compound [15, 16] or in the chocolate industry as an antioxidant [17]. Although resveratrol has been successfully extracted from several types of waste from the wine industry (seeds [18], grape skins [19], grape marc [4, 20, 21, 22, 23], stems [24, 25],leaves [26]), the highest level of resveratrol was determined in the prunings resulting from the annual winter pruning of the vineyard [27]. A wide range of research has shown that vine punings contain a large amount of trans-resveratrol [28]. In pruning waste, the predominant stilbenoids identified were trans-\(\varepsilon\)-vinefirin and trans-resveratrol [24]. Moreover, after the pruning, vine wastes still accumulate this compound [29], due to structural genes, 4 CL, PAL, C4H, and STS (forming trans-resveratrol), which are still active, the content of trans-resveratrol rising by up to 40 times post-harvest [30]. [PERSON] et al. (2014) analyzed the content of some parts of vine and grapes and reported that trans-resveratrol content starts rising in the spring months, meeting a maximum level in autumn, and then declines with the reduction in temperatures [27]. Both the plant growth conditions (climatic conditions and plant management) as well as the type and variety of _Vitis genus_ significantly influence the composition and concentration of stilbenes in the shoots. The content of stilbene can fluctuate depending on the variety, although the climatic conditions of agricultural cultivation of vines are the same. This is because stilbenes are a part of the plant's protection to pathogen infection, and varieties resistant to these infections will synthesize a greater amount of stilbenes [31]. Grapes (_Vitis_ spp.) are one of the world's largest fruit crops, with 74.5 million tons cultivated in 2014 [16]. The cultivation of vines annually generates significant amounts of viticulture waste, such as shoots, tendrils, leaves and wood, with an estimated amount of 1-5 t per hectare per year [30]. These wastes can represent a source of bioactive substances, especially due to the fact that they are usually composted or burned for disposal [1]. Polyphenols were extracted often from pruning wastes using different techniques, supercritical fluid extraction method being used lately [32; 33]. Lately, due to a rising widespread consumption of grapes and the massive waste generation, multiple uses were found for this waste.