foods Review Potential Health Benefits of Plant Food-Derived Bioactive Components: An Overview Mrinal Samtiya 1 , Rotimi E. Aluko 2 , Tejpal Dhewa 1,* and José Manuel Moreno-Rojas 3,* 1 Department of Nutrition Biology, School of Interdisciplinary and Applied Sciences, Central University of Haryana, Mahendergarh, Haryana 123031, India; [email protected] 2 Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada; [email protected] 3 Department of Food Science and Health, Andalusian Institute of Agricultural and Fisheries Research and Training (IFAPA), Alameda del Obispo, Avda. Menéndez Pidal, SN, 14004 Córdoba, Spain * Correspondence: [email protected] (T.D.); [email protected] (J.M.M.-R.) Abstract: Plant foods are consumed worldwide due to their immense energy density and nutritive value. Their consumption has been following an increasing trend due to several metabolic disorders linked to non-vegetarian diets. In addition to their nutritive value, plant foods contain several bioactive constituents that have been shown to possess health-promoting properties. Plant-derived bioactive compounds, such as biologically active proteins, polyphenols, phytosterols, biogenic amines, carotenoids, etc., have been reported to be beneficial for human health, for instance in cases of cancer, cardiovascular diseases, and diabetes, as well as for people with gut, immune function, and neurodegenerative disorders. Previous studies have reported that bioactive components possess antioxidative, anti-inflammatory, and immunomodulatory properties, in addition to improving intestinal barrier functioning etc., which contribute to their ability to mitigate the pathological impact of various human diseases. This review describes the bioactive components derived from fruit, Citation: Samtiya, M.; Aluko, R.E.; vegetables, cereals, and other plant sources with health promoting attributes, and the mechanisms Dhewa, T.; Moreno-Rojas, J.M. responsible for the bioactive properties of some of these plant components. This review mainly Potential Health Benefits of Plant compiles the potential of food derived bioactive compounds, providing information for researchers Food-Derived Bioactive Components: that may be valuable for devising future strategies such as choosing promising bioactive ingredients An Overview. Foods 2021, 10, 839. to make functional foods for various non-communicable disorders. https://doi.org/10.3390/foods10040839 Keywords: plant foods; bioactive components; antioxidants; polyphenols; anti-inflammatory; chronic Academic Editor: Isabel Sierra Alonso diseases; human health; gut health Received: 2 March 2021 Accepted: 6 April 2021 Published: 12 April 2021 1. Introduction Food delivers several nutrients that are essential for life as well as many molecules Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in or components with bioactive properties involved in health improvement and disease published maps and institutional affil- protection. Guidelines for a healthy diet recommend high intakes of plant-based foods such iations. as eating at least 400 g of fruits and vegetables on a daily basis [1]. Plants contain minerals that are necessary components of a healthy human diet, in addition to several primary and secondary metabolites that influence nutrition and human health [2]. Secondary metabolites are not crucial for the general development or functioning of plants, but these compounds present biological activity that makes them very useful as ingredients to Copyright: © 2021 by the authors. formulate traditional and modern medicines. Fruits and vegetables are rich sources of Licensee MDPI, Basel, Switzerland. This article is an open access article micronutrients (magnesium, calcium, and potassium) and bioactive components (including distributed under the terms and non-nutrients) consisting of phytochemicals such as polyphenols, dietary fiber, carotenoids, conditions of the Creative Commons and vitamins. Figure1 shows a brief overview of plant-derived bioactive compounds. Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). Foods 2021, 10, 839. https://doi.org/10.3390/foods10040839 https://www.mdpi.com/journal/foods FoodsFoods 20212021,, 1010,, 839 x FOR PEER REVIEW 2 of 25 2 of 23 FigureFigure 1. Brief 1. overview Brief overview of plant-derived of plant bioactive-derived compounds. bioactive compounds. It has been established that more than 5000 different phytochemical compounds are presentIt inhas grains, been vegetables established and fruits,that more though than many 5000 more different remain unidentified phytochemical [3]. compounds are Enormouslypresent advantageousin grains, vegetables attributes of wholeand fruits, grains, though vegetables, many and fruits more have remain been unidentified [3]. associatedEnormous with bioactively advantageous non-nutritional attributes chemical of components whole grains, commonly vegetables, known as phy-and fruits have been tochemicals.associated It has with been bioactive suggested thatnon whole-nutritional foods may chemical have 5000–25,000 components individual commonly known as phytochemicalsphytochemicals. with potentially It has been bioactive suggested properties that [whole4,5]. Cereals foods and may pulses have are 5000 vi-–25,000 individual tal sources of fiber (dietary), minerals, proteins, calories, vitamins, and antioxidants, all of whichphytochemicals have been confirmed with potential as functionally bioactive food constituents properties [6]. The [4,5] wide. Cereals variety and of pulses are vital secondarysources metabolites of fiber present (dietary), in plant minerals, sources include prote glycoalkaloids,ins, calories, antioxidantvitamins, compo-and antioxidants, all of nents,which and vitamins, have been which confirmed have been confirmed as functional to have food many constituents beneficial effects [6] for. The human wide variety of sec- health,ondary for instance metabolites antioxidative, present anti-inflammatory in plant sources and cardioprotectiveinclude glycoalkaloids, properties, inantioxidant compo- addition to preventing obesity and regulating diabetes [2,7]. Fruit is the fleshy part of plantsnents, that is and sweet vitamins, or sour and which edible inhave its raw bee state.n confirmed It provides to ample have sources many of beneficial sugars, effects for hu- vitaminsman and health, bioactive for ingredientsinstance antioxidative, such as phenols andanti fiber-inflammatory that have been and reported cardioprotective for proper- theirties biological, in addition activity to which preventing is related obesity with their and ability regulating to attenuate diabetes the progression [2,7]. Fruit of is the fleshy part certainof degenerativeplants that disordersis sweet [ 8o].r sour and edible in its raw state. It provides ample sources of sugarsPlant-derived, vitamins natural and antioxidants bioactive areingredients principally such polyphenols, as phenols such asand stilbenes, fiber that have been re- anthocyanins, flavonoids, lignans, and phenolic acids, in addition to carotenoids (carotenes andported xanthophylls), for their vitamins biological C, and vitaminactivit E.y Thesewhich natural is related antioxidants, with their in particular ability to attenuate the carotenoidsprogression and polyphenols, of certain degenerative possess a wide disorders variety of biological[8]. attributes, such as anti-aging, Plant anti-inflammatory,-derived natural anti-viral, antioxidants anti-microbial, are and principally anti-cancer propertiespolyphenols [9–11]., such as stilbenes, anthocyanins,Recently, food-derived flavonoids, proteins lignans or peptides, and have phenolic gained acids importance, in addition due to their to carotenoids (caro- bioactive properties, which were shown to be dependent on their amino acid sequences [12]. tenes and xanthophylls), vitamins C, and vitamin E. These natural antioxidants, in par- ticular carotenoids and polyphenols, possess a wide variety of biological attributes, such as anti-aging, anti-inflammatory, anti-viral, anti-microbial, and anti-cancer properties [9–11]. Recently, food-derived proteins or peptides have gained importance due to their bioactive properties, which were shown to be dependent on their amino acid sequences [12]. Bioactive peptides are defined as specific amino acid sequences that exhibit a useful biological activity or with exert a positive influence on human health and body functions, regardless of their nutritive importance [13]. It has been reported that plant proteins contain bioactive peptides (BAPs) as inactive amino acid sequences when present within Foods 2021, 10, 839 3 of 25 Bioactive peptides are defined as specific amino acid sequences that exhibit a useful biological activity or with exert a positive influence on human health and body functions, regardless of their nutritive importance [13]. It has been reported that plant proteins contain bioactive peptides (BAPs) as inactive amino acid sequences when present within the native protein. However, BAPs can be readily released by various processes including fermentation, in vitro or human gastrointestinal tract enzyme-catalyzed proteolysis, and food processing [14–16]. BAPs have been reported in legumes that may prevent chronic disorders, but research studies related to cereals remain limited [17]. This review focuses on the bioactive components of plant foods, such as fruits, vegetables, cereals, grains, and their potential relevance