Hop Compounds: Extraction Techniques, Chemical Analyses, Antioxidative, Antimicrobial, and Anticarcinogenic Effects

Abstract

Hop plants comprise a variety of natural compounds greatly differing in their structure and properties. A wide range of methods have been developed for their isolation and chemical analysis, as well as for determining their antioxidative, antimicrobial, and antigenotoxic potentials. This contribution provides an overview of extraction and fractionation techniques of the most important hop compounds known for their health-promoting features. Although hops remain the principal ingredient for providing the taste, stability, and antimicrobial protection of beer, they have found applications in the pharmaceutical and other food industries as well. This review focuses on numerous health-promoting effects of hops raging from antioxidative, sedative, and anti-inflammatory potentials, over anticarcinogenic features to estrogenic activity. Therefore, hops should be exploited for the prevention and even healing of several prevalent diseases like cardiovascular disorders and various cancer types. New ideas for future studies on hops are finally presented: computational investigations of chemical reactivities of hop compounds, nanoencapsulation, and synergistic effects leading to a higher bioavailability of biologically active substances as well as the application of waste hop biomass from breweries for the production of high-added-value products in accordance with the biorefinery concept.

Yield, Growth, Quality, Biochemical Characteristics and Elemental Composition of Plant Parts of Celery Leafy, Stalk and Root Types Grown in the Northern Hemisphere

“…Salehi et al [1] reports that celery flavonoids are represented by miricetin, quercetin, kaempferol, luteolin and apigenin, and the high levels of antioxidants determine its resistance to oxidative stress. Indeed, quercetin, kaempferol and apigenin exert strong anticarcinogenic effects by promoting apoptosis [23], and luteolin, quercetin and kaempferol display inhibition of estrogenic action [24].…”

Optimization of Enzyme-Assisted Extraction of Flavonoids from Corn Husks

“…The health-promoting properties of flavonoids are believed to arise primarily from their ability to scavenge free radicals and/or chelate metal ions [21]. In addition to being effective antioxidants, some of these compounds possess chemopreventive properties, which have been related to their capacity to interfere with the carcinogenesis process (initiation, promotion, and progression) [22,23]. Furthermore, mounting evidence from in vitro, in vivo, and epidemiological studies suggests that they may exert anti-inflammatory, anti-allergic, and antibacterial activities [21].…”

Microbial Growth and Biogenic Amine Production in a Balkan-Style Fresh Sausage during Refrigerated Storage under a CO2-Containing Anaerobic Atmosphere: Effect of the Addition of Zataria multiflora Essential Oil and Hops Extract

“…A current approach to extend the shelf-life of fresh sausages is the use of natural antimicrobials [9]. Hops, the strobiles (female flowers) of the Humulus lupulus L. plant, which are commonly used in brewery and have found application in other foods [10], appear to be a potentially suitable ingredient for this purpose. Hops contains antimicrobial compounds, such as prenylated acylphloroglucinols, bitter acids or xanthohumol, among others, which have been probed to inhibit Gram-positive bacteria [11,12].…”