Goji berries have long been used for their nutritional value and medicinal purposes in Asian countries. In the last two decades, goji berries have become popular around the world and are consumed as a functional food due to wide-range bioactive compounds with health-promoting properties. In addition, they are gaining increased research attention as a source of functional ingredients with potential industrial applications. This review focuses on the antioxidant properties of goji berries, scientific evidence on their health effects based on human interventional studies, safety concerns, goji berry processing technologies, and applications of goji berry-based ingredients in developing functional food products.
Since the fruits of Lycium L. species (Fructus lycii, goji berries) are promoted as a “superfood” with plenty of health benefits, there is extensive research interest in their nutritional and phytochemical composition. In the present study, the nutritional value, minerals, fatty acid composition, and bioactive compounds of L. barbarum L., red, yellow, and black goji berry (L. ruthenicum Murray.) cultivated in Serbia were investigated. Antioxidant and antimicrobial properties of their methanol extracts were assessed. Red goji berry had the highest content of fats, dietary fiber, iron, total carotenoids, and 2-O-β-d-glucopyranosyl-l-ascorbic acid (AA-2βG). The yellow goji berry extract showed the highest level of flavonoids and the most prominent antimicrobial (especially against Gram-negative bacteria) properties. The highest total phenolic content and the most potent antioxidant activity were observed for the extract of black goji berry. Therefore, all goji berries could be a valuable source of bioactive compounds in the food and pharmaceutical industry.
Blackthorn (Prunus spinosa L.) fruit is bluish-black wild fruit traditionally used in nutrition and medicine. It is recently gaining attention as a functional food and an underutilized source of bioactive compounds for application in the food and pharmaceutical industry. This study aimed to assess the health-promoting potential of blackthorn fruits from Serbia by examining their chemical composition and in vitro biological activities. Phytochemical analysis of the blackthorn fruit extracts was performed using LC-DAD-ESI-MS. The total phenolic (TPC), total flavonoid (TFC), total anthocyanin (TAC) content, antioxidant capacity, and enzyme inhibitory activities were determined spectrophotometrically. The antimicrobial and prebiotic properties were tested using the broth microdilution method. Twenty-seven phenolics belonging to the classes of hydroxybenzoic and hydroxycinnamic acids derivatives, flavonoids, and anthocyanins were identified, with caffeoylquinic acid as the most abundant compound. Blackthorn extracts were characterized by notable TPCs, TFCs, and TACs, and free radical scavenging and reducing ability. The enzyme inhibitory effects (IC50 = 0.43–2.16 mg/mL) were observed towards α-amylase, α-glucosidase, acetylcholinesterase, and tyrosinase. Blackthorn fruit extracts in a concentration-dependent manner (0.3–5 mg/mL) stimulated the growth of several probiotic microorganisms and their mixtures, especially the yeast Saccharomyces boulardii. Obtained results support further evaluation of the functional food potential of blackthorn fruit.
The current trend in food innovations includes developing products containing plant ingredients or extracts rich in bioactive compounds. This study aimed to prepare and characterize skimmed thermally treated goat’s milk powders enriched with lyophilized fruit extracts of Lycium ruthenicum Murray (GMLR) and Lycium barbarum L. (GMLB). Proximate analysis, ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS), Fourier transform infrared spectroscopy using attenuated total reflection (FTIR-ATR), and electrophoretic analysis were assessed. Total phenolic content (TPC), total protein content, and antioxidant properties of enriched goat milk powders were determined spectrophotometrically, and prebiotic potential was evaluated by the broth microdilution method. A total of 25 phenolic compounds and 18 phenylamides were detected in the enriched goat milk powders. Electrophoretic analysis showed the absence of proteolysis in the prepared powders. The GMLR showed the highest TPC and displayed a ferric ion-reducing power, probably contributed by anthocyanins and some phenylamides. GMLR and GMLB had higher ABTS radical scavenging activity but lower ferrous ion-chelating capacity than control goat′s milk powder. GMLB and GMLR in a dose-dependent manner (0.3–5 mg/mL) showed a growth-promoting effect on probiotic strains. In summary, prepared goji/goat milk powders, primarily GMLR, might be used as prebiotic supplements or functional food additives.
Goji berry is a rich source of polyphenols, carotenoids and polysaccharides, contributing to its diverse biological activities. Due to their high water content and perishability, the berries are often processed into dried forms or juices. This study hypothesized that juice obtained from Serbian-grown goji berries would exhibit a distinctive phytochemical composition and significant in vitro antioxidant and hypoglycemic potential. Antioxidant activity was assessed using DPPH, ABTS, CUPRAC, FRAP and β-carotene bleaching assays, while hypoglycemic potential was evaluated via α-amylase and α-glucosidase inhibition. The analyzed goji juice exhibited mild acidity and moderate sweetness. In terms of bioactive composition, the juice contained high levels of polyphenols (194.50 ± 3.88 mg GAE/100 mL) exceeding the values reported for most commercial fruit juices, as well as notable levels of flavonoids (70.30 ± 5.11 mg CE/100 mL), carotenoids (289.53 ± 0.65 µg/100 mL) and polysaccharides (375.20 ± 12.46 mg Glu/100 mL), along with minerals, particularly potassium and copper. It also showed strong antioxidant capacity and concentration-dependent inhibition of α-amylase (IC50 = 5.28 ± 0.26 mg/mL) and α-glucosidase (IC50 = 10.12 ± 0.23 mg/mL). This study provides the first comprehensive characterization of Serbian-grown goji berry juice, confirming its potential as a functional ingredient.