The fruits of Vaccinium oxycoccos L. are an important source of bioactive compounds with antibacterial, antifungal, and anti-inflammatory effects. Studies on the phytochemical analysis of cranberry fruit samples showed that the qualitative and quantitative composition of biologically active compounds varied in cranberry fruit samples collected from different types of wetland sites: the total anthocyanin content was 698 ± 24–8352 ± 200 µg/g, the total flavonol content—518 ± 16–2811 ± 31 µg/g, the total content of triterpene compounds—4060 ± 122–6542 ± 157 µg/g, the content of chlorogenic acid—17 ± 0.4 µg/g to 1224 ± 41 µg/g, and the total content of proanthocyanidins—919 ± 19 µg EE/g to 3038 ± 137 µg EE/g. The percentage composition of anthocyanins in cranberry fruit varied between the different wetland sites: in some cranberry fruit samples, four anthocyanins (cyanidin-3-galactoside, cyanidin-3-arabinoside, peonidin-3-galactoside, and peonidin-3-arabinoside) were predominant, while in other samples, six anthocyanins (cyanidin-3-galactoside, cyanidin-3-arabinoside, peonidin-3-galactoside, peonidin-3-arabinoside, cyanidin-3-glucoside, and peonidin-3-glucoside) predominated. The results of these studies showed the differences in the composition of secondary metabolites in the studied cranberry samples and prove that the standardization of the qualitative and quantitative composition of cranberry fruit raw materials and the application of routine tests are necessary for the expansion of the use of botanical raw materials in the production of functional foods and phytopreparations.

We carried out a qualitative and quantitative analysis of the phytochemical composition of the fruits of large cranberry cultivars ‘Ben Lear’, ‘Bergman’, ‘Kalnciema agra’, ‘Lemunyon’, ‘Pilgrim’, ‘Stevens’, and ‘Tina’ grown in Latvian climatic conditions. The following predominant compounds were found in cranberry fruit samples: peonidin-3-O-galactoside, peonidin-3-O-arabinoside, cyanidin-3-O-galactoside, cyanidin-3-O-arabinoside, myricetin-3-galactoside, quercetin-3-galactoside, quercetin-3-α-L-arabinofuranoside, quercetin 3-rhamnoside, ursolic acid, and oleanolic acid. During the berry ripening period (from 16 August until 15 September), a trend of decreasing amounts of compounds was found in the fruit samples of the studied cranberry cultivars: the total amount of proanthocyanidins decreased by 1.3 times, the total amount of the identified flavonols decreased by 1.3 times, the total amount of triterpenoids decreased by 1.2 times, and the total amount of chlorogenic acid decreased by 1.7 times. During the period from 16 August until 15 September, the total amount of anthocyanins in the cranberry fruit samples increased by 2.6 to 17 times. The highest total amount of anthocyanins (5305.80 ± 27 µg/g) was detected in fruit samples of the cranberry cultivar ‘Kalnciema agra’ collected on 15 September. The amount of biologically active compounds in cranberry fruit samples varies during berry ripening. Thus, the choice of the picking time is one of the factors that determines the phytochemical composition of raw cranberry material.

In our investigation, we evaluated the content of chlorogenic acid, proanthocyanidins, anthocyanins, flavonols, triterpenoids, and phytosterols in cranberry fruit extracts of the cultivars ‘Baifay’, ‘Early Black’, ‘Howes’, ‘Pilgrim’, ‘Red Star’, and ‘Stevens’ grown in Lithuania, as well as changes in the antioxidant activity in extracts of fruit samples of these cultivars during the period of berry maturation. The highest amount of proanthocyanidins (8.87 ± 0.57 mg EE/g EE) and flavonols (3688.52 ± 22.85 µg/g) was determined in cranberries of the cultivar ‘Howes’ harvested on 12 August. Remarkably, the highest anthocyanins content (9628.62 ± 266 µg/g) was determined in cranberries of the cultivar ‘Howes’ harvested on 22 October. The study showed that the content of phytochemical compounds in cranberries varied between 12 August and 22 October; the content of proanthocyanidins decreased by a factor of about 2, the content of chlorogenic acid decreased by a factor of about 1.3, the content of flavonols decreased by a factor of about 2, and the content of anthocyanins increased by 27 to 450 times. A strong correlation was found between the total proanthocyanidin content of cranberry fruit extracts and their in vitro antiradical and reducing activity (r = 0.781 and 0.726, respectively, p < 0.001). The data of our study detail the accumulation of the phytochemical composition of biologically active compounds in cranberry samples during the stages of maturity, therefore these data are significant for the assessment of harvest time of cranberry and can be applied to select cranberry cultivars for further cultivation in Lithuanian climatic conditions.

Cranberry fruits are an important source of anthocyanins and anthocyanidins. The aim of the present study was to investigate the effect of excipients on the solubility of cranberry anthocyanins and their dissolution kinetics as well as on the disintegration time of the capsules. Selected excipients (sodium carboxymethyl cellulose, beta-cyclodextrin and chitosan) were found to affect the solubility and release kinetics of anthocyanins in freeze-dried cranberry powder. Capsule formulations N1–N9 had a disintegration time of less than 10 min, and capsule formulation N10 containing 0.200 g of freeze-dried cranberry powder, 0.100 g of Prosolv (combination of microcrystalline cellulose and colloidal silicon dioxide), and 0.100 g of chitosan had a capsule disintegration time of over 30 min. The total amount of anthocyanins released into the acceptor medium ranged from 1.26 ± 0.06 mg to 1.56 ± 0.03 mg. Capsule dissolution test data showed that the time to release into the acceptor medium was statistically significantly longer for the chitosan-containing capsule formulations compared to the control capsules (p < 0.05). Freeze-dried cranberry fruit powder is a potential source of anthocyanin-rich dietary supplements, and the choice of excipient chitosan could be a suitable solution in capsule formulations providing greater anthocyanin stability and modified release in the gastrointestinal tract.

The phytochemical diversity and potential health benefits of V. oxycoccos and V. macrocarpon fruits call for further scientific inquiry. Our study aimed to determine the phytochemical composition of extracts from these fruits and assess their antioxidant, antibacterial, and anticancer properties in vitro. It was found that the ethanolic extracts of V. oxycoccos and V. macrocarpon fruits, which contained more lipophilic compounds, had 2–14 times lower antioxidant activity compared to the dry aqueous extracts of cranberry fruit, which contained more hydrophilic compounds. All tested cranberry fruit extracts (OE, OW, ME, and MW) significantly inhibited the growth of bacterial strains S. aureus, S. epidermidis, E. coli, and K. pneumoniae in vitro compared to the control. Cytotoxic activity against the human prostate carcinoma PPC-1 cell line, human renal carcinoma cell line (CaKi-1), and human foreskin fibroblasts (HF) was determined using an MTT assay. Furthermore, the effect of the cranberry fruit extract samples on cell migration activity, cancer spheroid growth, and viability was examined. The ethanolic extract from V. macrocarpon fruits (ME) showed higher selectivity in inhibiting the viability of prostate and renal cancer cell lines compared to fibroblasts. It also effectively hindered the migration of these cancer cell lines. Additionally, the V. macrocarpon fruit extract (ME) demonstrated potent cytotoxicity against PPC-1 and CaKi-1 spheroids, significantly reducing the size of PPC-1 spheroids compared to the control. These findings suggest that cranberry fruit extracts, particularly the ethanolic extract from V. macrocarpon fruits, have promising potential as natural remedies for bacterial infections and cancer therapy.

In this study, we conducted a qualitative and quantitative analysis of anthocyanins, proanthocyanidins, flavonols and triterpenoids in samples of introduced and bred large cranberry fruits from the collection of the National Botanic Garden of Latvia. The highest total anthocyanin levels (8638–9316 µg/g) were detected in the fruit samples of the cranberry cultivars ‘Black Veil’, ‘Franclin’ and ‘Early Black’. The highest total proanthocyanidin levels (2775–3389 µg/g) were found in cranberries of cultivars ‘Kalnciema Agrā’, ‘Kalnciema Tumšā’, ‘Searles’, ‘Howes’, and ‘Kalnciema Ražīgā’. The highest levels of flavonol compounds (1373–1402 µg/g) were detected in cranberries of cultivars ‘Howes’, ‘Black Veil’ and ‘Salaspils Melnās’. The highest levels of triterpenoids (5292–5792 µg/g) were determined in cranberries of cultivars ‘Kalnciema Agrā’, ‘Septembra’, ‘Džbrūklene’ and ‘Early Black’. The results of our study allow for the estimation of differences in the content of secondary metabolites in the fruit samples of the studied cranberry cultivars and for the selection of promising cultivars for further introduction and cultivation in the climatic conditions of the Baltic countries. These results are also important for the selection of the most promising cranberry cultivars for the preparation of cranberry raw material, and the high-quality composition of plant material ensures the effectiveness of cranberry supplements and other cranberry preparations.