The current interest of the scientific community for the exploitation of high-value compounds from macroalgae is related to the increasing knowledge of their biological activities and health benefits. Macroalgae phenolic compounds, particularly phlorotannins, have gained particular attention due to their specific bioactivities, including antioxidant, antiproliferative, or antidiabetic. Notwithstanding, the characterization of macroalgae phenolic compounds is a multi-step task, with high challenges associated with their isolation and characterization, due to the highly complex and polysaccharide-rich matrix of macroalgae. Therefore, this fraction is far from being fully explored. In fact, a critical revision of the extraction and characterization methodologies already used in the analysis of phenolic compounds from macroalgae is lacking in the literature, and it is of uttermost importance to compile validated methodologies and discourage misleading practices. The aim of this review is to discuss the state-of-the-art of phenolic compounds already identified in green, red, and brown macroalgae, reviewing their structural classification, as well as critically discussing extraction methodologies, chromatographic separation techniques, and the analytical strategies for their characterization, including information about structural identification techniques and key spectroscopic profiles. For the first time, mass spectrometry data of phlorotannins, a chemical family quite exclusive of macroalgae, is compiled and discussed.

Passiflora is a highly diverse genus where taxonomic lack of consensus remains. This may be the reason why numerous studies do not specify to the infraspecific level the plant material used or lack consistency in the nomenclature of botanical formae of Passiflora edulis. Ultimately, this may contribute to inaccurate chemical composition and health effects attributed to different Passiflora edulis species and formae. Hence, this review aims to overcome these challenges by exploring the phytochemical profile, specific nutritional value and potential health benefits of purple passion fruit (PPF). PPF is often consumed fresh for its pulp (including seeds) or juice, either directly or added to food dishes. It is also used industrially to produce a wide range of products, where peels and seeds are abundant by-products, most often discarded or used in low-value applications. Herein, in a perspective of integral valorisation of the fruit, the potential use of all PPF fractions (peel, pulp and seeds) is discussed as a source of important macro and micronutrients, adequate to integrate a balanced and healthy diet. In addition, the phytochemical profile of such fractions is also discussed along with the associated in vitro biological activities (antioxidant, anti-inflammatory, antibacterial and antifungal) and in vivo beneficial effects in the management of several diseases (asthma, hypertension, osteoarthritis, diabetes and pulmonary fibrosis). In summary, this review gathers the current knowledge on the nutritional and phytochemical composition of PPF and highlights the potential of using all fractions as a source of ingredients in food formulations that promote health and well-being. At the same time, it also contributes to defining sustainable strategies for an integrated valorisation of this natural product.