Sea buckthorn oil, derived from the fruits of the shrub, also termed seaberry or sandthorn, is without doubt a strikingly rich source of carotenoids, in particular zeaxanthin and β-carotene. In the present study, sea buckthorn oil and an oil-in-water emulsion were subjected to a simulated gastro-intestinal in vitro digestion, with the main focus on xanthophyll bioaccessibility. Zeaxanthin mono- and di-esters were the predominant carotenoids in sea buckthorn oil, with zeaxanthin dipalmitate as the major compound (38.0%). A typical fatty acid profile was found, with palmitic (49.4%), palmitoleic (28.0%), and oleic (11.7%) acids as the dominant fatty acids. Taking into account the high amount of carotenoid esters present in sea buckthorn oil, the use of cholesterol esterase was included in the in vitro digestion protocol. Total carotenoid bioaccessibility was higher for the oil-in-water emulsion (22.5%) compared to sea buckthorn oil (18.0%) and even higher upon the addition of cholesterol esterase (28.0% and 21.2%, respectively). In the case of sea buckthorn oil, of all the free carotenoids, zeaxanthin had the highest bioaccessibility (61.5%), followed by lutein (48.9%), making sea buckthorn oil a potential attractive source of bioaccessible xanthophylls.

Recent trends in the food industry combined with novel methods in agriculture could transform rowan into a valuable raw material with potential technological applications. Thus, the aim of this research was to investigate the content of bioactive compounds in its fruits and to assess the color and antioxidant stability of the extracts prepared from such fruits during various thermal treatments and at different pH and ionic strength values. Various spectrophotometric methods, HPLC, and capillary electrophoresis were used to quantify the concentrations of bioactive compounds—polyphenols, carotenoids, organic acids, and to assess antioxidant activity and color. The results show that rowan berries contain circa 1.34–1.47 g/100 g of polyphenols among which include catechin, epicatechin, ferulic acid methyl ester, procyanidin B1, etc.; ca 21.65 mg/100 g of carotenoids including zeaxanthin, β-cryptoxanthin, all-trans-β-carotene, and various organic acids such as malic, citric, and succinic, which result in a high antioxidant activity of 5.8 mmol TE/100 g. Results also showed that antioxidant activity exhibited high stability when the extract was subjected to various thermal treatments, pHs, and ionic strengths, while color was mainly impacted negatively when a temperature of 100 °C was employed. This data confirms the technological potential of this traditional, yet often overlooked species.

The bioaccessibility of the major carotenoids present in two commercial microalgal supplements in powder form was investigated through a standardized in vitro digestion method. The dried biomass of Arthrospira platensis contained β‐carotene (36.8 mg/100 g) and zeaxanthin (20.8 mg/100 g) as the main carotenoids as well as a high content of saturated fatty acids (61% of total fatty acids), whereas that of Chlorella pyrenoidosa was rich in lutein (37.8 mg/100 g) and had a high level of unsaturated fatty acids (65% of total fatty acids). In the case of the latter, lutein bioaccessibility was not statistically enhanced after the replacement of porcine bile extract with bovine bile extract in the in vitro digestion protocol and after the addition of coconut oil (17.8% as against to 19.2% and 19.2% vs. 18.5%, respectively). In contrast, the use of bovine bile extract along with co‐digestion with coconut oil significantly enhanced the bioaccessibility of zeaxanthin from A. platensis, reaching the highest bioaccessibility of 42.8%.

As it exhibits no provitamin A activity, the dietary intake of zeaxanthin is not considered essential. However, its contribution to ocular health has long been acknowledged. Numerous publications emphasize the importance of zeaxanthin alongside lutein in ocular diseases such as cataracts and age-related macular degeneration which constitute an important health concern, especially among the elderly. Considering that the average dietary ratio of lutein to zeaxanthin favors the first, more bioaccessible food sources of zeaxanthin that can hinder the development and progression of the above-mentioned disorders are of great interest. In this paper, a brief overview of the more recent state of knowledge as regards dietary sources together with their respective zeaxanthin bioaccessibility assessed through a standardized in vitro digestion method was provided.

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The present study investigated the carotenoid content and composition of several commercial eggs produced in different housing systems and the amount of macular xanthophylls that becomes available for absorption by the intestinal cells (bio-accessible) after the ingestion of boiled organic egg yolks. The highest total carotenoid content was observed in the case of organic egg yolks (7.02 mg/100 g). Carotenoid concentration varied not only between egg yolks obtained through different housing methods (free-range, barn and battery-cage), but also between egg yolks from the same housing method obtained by different producers. Except for organic egg yolks that had lutein and zeaxanthin as the major carotenoids, canthaxanthin was observed in all the investigated egg yolks to a different extent. Both lutein and zeaxanthin displayed a high bioaccessibility from boiled organic egg yolks, 86% and 91%, respectively).

The chlorophylls, carotenoids, total polyphenols contents and antioxidant activity in fresh and stored Parsley, celery and dill leaves were comparatively determined by spectrophotometric and high performance liquid chromatography (HPLC) methods. Results indicated that freezing does not induce significant changes in chlorophyll concentration. Drying induces significant decreases, varying according to the analyzed plant; parsley (60%), followed by dill (56.4%) and celery (45.3%). The carotenoids identified in all plants were lutein, b-carotene and cis-β-carotene. Fresh parsley leaves showed the highest total carotenoid concentration (21.64 mg/100g FW), followed by celery (15.41 mg/100g FW) and dill (14.95 mg/100g FW). Total polyphenols had an average concentration of 2.15 mg/g FW in parsley; 2.7 mg/g FW in dill and almost the double, 4.13 mg/g FW in celery. Drying of leaves induced a decrease with approximately 50% of the total polyphenol concentration, while freezing, did not significantly affect it. The highest antioxidant activity was observed in the dill, followed by parsley and celery. In both types of methods (freezing and drying in the oven), decreases in antioxidant activity were observed.