## 1 Introduction  
The global superfood market of was estimated to be worth USD 182.15 billion in 2023 and is expected to grow at an annual rate of 4.0% until 2030 [1]. In general, the term \"superfood\" refers to natural or minimally processed foods believed to have exceptional nutritional value [2]. These foods include mostly products of plant origin rich in nutrients and phytochemicals, such as certain fruits, vegetables, seeds, nuts, legumes, seaweed, spices, and herbs [3, 4]. The term \"superfood\" has been widely used in web search tools, social media sites, and marketing communication platforms, although it has no legal or clear scientific definition [4, 5]. Due to the ambiguity of the definition, the perception of superfoods is very subjective. Therefore, consumers' attitudes towards these products have recently been the subject of research in several countries, including the United Kingdom [6], Switzerland [7], Germany [5; 8], Slovenia [9], Malaysia [10], and India [11]. The findings of these studies suggest that superfoods are preferred by certain segments of consumers, primarily due to their perceived dietary and therapeutic benefits beyond basic nutrition.  
Superfoods are widely marketed in the form of powders, which are generally obtained by drying and size reduction of plant materials. Common dehydration methods include spray drying and freeze drying, while size reduction is achieved by crushing, grinding, or other pulverization methods. These processes concentrate nutrients and enable a longer shelf life, making powdered products more attractive for some consumers. In addition, powdering of foods may contribute to sustainable food production as it reduces the energy demand of storage and transport and minimizes food waste [12]. Superfood powders are generally categorized as food supplements or nutraceuticals, and they can also be used as ingredients of functional foods. These categories include products that are at the interface between nutrition and medicine. While functional foods usually refer to value-added products similar to regular foods, food supplements and nutraceuticals are marketed in doseable forms like capsules, tablets, powders, or ampoules of liquids [13]. To date, extensive research has been conducted related to nutraceuticals, focusing mainly on their safety, nutritional value, and potential biological activities [3; 14; 15; 16]. Nevertheless, there is a lack of comparative experimental studies on the nutritional value and functional properties of commercially available products. Scientific information is also incomplete regarding their odorants and other attributes that directly influence their sensory properties and consumers' acceptance.  
The aim of our work was to compare sixteen commercial nutraceutical powders that are marketed as superfoods, based on their composition, antioxidant capacity, and antimicrobial activity. In addition, the volatile fraction of the products was analyzed, as aromatic volatiles play important role in the biological activity and sensory characteristics of foods [17; 18]. For a comprehensive view, we aimed to compare products made from a large variety of raw materials. Our samples included powders of plants traditionally consumed in the Western world (e.g., spinach, rosehip, and ginger powders) and products that are made of raw materials considered exotic in most countries (e.g., goji berry, acerola, and moringa powders). In addition, microalgae and duckweed powders, as alternative nutrient sources, were also investigated.