Opportunities for plant-derived enhancers for iron,zinc, and calcium bioavailability: A review

Understanding of the mechanism of interactions between dietary elements, their salts, and complexing/binding ligands is vital to manage both deficiency and toxicity associated with essential element bioavailability. Numerous mineral ligands are found in both animal and plant foods and are known to exert bioactivity via element chelation resulting in modulation of antioxidant capacity or micobiome metabolism among other physiological outcomes. However, little is explored in the context of dietary mineral ligands and element bioavailability enhancement, particularly with respect to ligands from plant-derived food sources. This review highlights a novel perspective to consider various plant macro/micronutrients as prospective bioavailability enhancing ligands of three essential elements (Fe, Zn, and Ca). We also delineate the molecular mechanisms of the ligand-binding interactions underlying mineral bioaccessibility at the luminal level. We conclude that despite current understandings of some of the structure–activity relationships associated with strong mineral–ligand binding, the physiological links between ligands as element carriers and uptake at targeted sites throughout the gastrointestinal (GI) tract still require more research. The binding behavior of potential ligands in the human diet should be further elucidated and validated using pharmacokinetic approaches and GI models.     

Comparison of Properties of New Sources of Partially Purified Inulin to Those of Commercially Pure Chicory Inulin

Newly developed inulin powders were prepared from roots of Asparagus falcatus (AF) and Taraxacum javanicum (TJ) plants grown in Sri Lanka. Inulin content, analyzed by enzymatic spectrophotometric as well as high‐performance liquid chromatographic methods, showed that AF and TJ inulin powders contain 65.5% and 45.4% (dry wt) inulin, respectively, compared with 72% dry wt in the commercially available chicory inulin. Treating the AF and TJ inulin powders using ion exchange techniques significantly (P < 0.05) reduced their contents of micro (Zn, Cu, Mn, Fe) and macro (Na, K, Ca, Mg) elements. Enzymatic hydrolysis of inulin into fructose and glucose by fructanase, and FT‐IR analyses proved that the developed AF and TJ inulins have characteristic molecular composition similar to commercial inulin. TJ inulin contained significantly (P < 0.05) greater amounts of total phenolics (4.37 mg GAE/g), total flavonoids (2.79 mg QE/g), and antioxidant capacity (833.11 mM TE/g) than AF inulin, which contained 1.33 mg GAE/g of total phenolics, 0.43 mg QE/g of total flavonoids, and 406.26 mM TE/g antioxidant capacity. The current study suggests that the newly developed inulin from AF and TJ roots could be used as an alternative commercial source of inulin for the food industry.     

Characterization of Date (Deglet Nour) Seed Free and Bound Polyphenols by High‐Performance Liquid Chromatography‐Mass Spectrometry

Date (Pheonix dactylifera L.) seeds are a valuable and abundant by‐product with various potential food applications. Free polyphenols (FPPs) and bound polyphenols (BPPs) of date seeds from Deglet Nour variety grown in Australia were investigated using high‐performance liquid chromatography‐mass spectrometry. The FPP fraction contained the following main phenolic compounds per gram of date seed powder; procyanidin B1 (499.8 ± 7.8 μg), procyanidin B2 (288.6 ± 6.1 μg), catechin (167.6 ± 2.1 μg), epicatechin (39.44 ± 0.39 μg), and protocatechuic acid (1.77 ± 0.22 μg). Additionally, one of the 2 A‐type dimers was confirmed as procyanidin A2 (24.05 ± 0.12 μg/g). A‐type dimers have not been reported before in date seeds. The BPP fraction contained epicatechin (52.59 ± 0.76 μg/g) and procyanidin B2 (294.2 ± 3.7 μg/g), while several peaks exhibiting ESI^? m/z of 153 indicated dihydroxybenzoic acid isomers including protocatechuic acid (2.138 ± 0.025 μg/g). These findings contributed to our knowledge of date seed phytochemicals and understanding of their contribution to the reported bioactivities.     

Antioxidant and antiproliferation effects of extractable and nonextractable polyphenols isolated from apple waste using different extraction methods

Fruits and vegetables waste byproducts could be utilized as a good source of cheap antioxidants for improving human health and reducing the risks of some chronic diseases. Results from examining industrial apple waste revealed that the total polyphenolic content in nonextractable polyphenols (NEPPs) reached 539.84 ± 8.90 mg as gallic acid equivalents/1 g of dry wt. in comparison to 77.26 ± 11.53 mg dry wt. of extractable polyphenols (EPPs). The antioxidant activities of NEPPs reported as percentage reduction in 2,2-Diphenyl-1-picrylhydrazyl and 2'.2'-azinobis(3-ethylbenzothiazline-6-sulfonic acid) diammonium salt were 89.76 ± 0.93% and 99.78 ± 0.38%, respectively. In addition, the antiproliferation study on human HeLa, HepG2, and HT-29 cancer cells showed that NEPPs at the concentration of 1 mg/mL had significant inhibitory effects against all tested cancer cells (46.2% to 95%), where EPP showed lower effect (3.9% to 22.2%). These results clearly indicated that NEPPs from industrial apple waste could be a good source of natural antioxidants with significant antiproliferation efficacy against human cancer cells.     

Simulated gastrointestinal digestion and in vitro colonic fermentation of date (Phoenix dactylifera L.) seed polyphenols

Date seeds are a by‐product of date fruit industry and a rich source of polyphenols. In this study, in vitro bioaccessibility and colonic fermentation of major polyphenols from date seed powder (DSP) and DSP‐fortified yoghurt (DSPY) were investigated using HPLC. Catechin, epicatechin and procyanidin A2, B1 and B2 were stable during simulated gastric and sequential intestinal digestion. Bioaccessibility was significantly (P < 0.05) higher for all compounds from DSPY compared with DSP. After in vitro colonic fermentation of insoluble digestion materials, most of the target compounds were metabolised by faecal bacteria to ferulic acid, 3‐hydroxyphenylacetic acid, 3‐phenylpropionic acid and 3‐(4‐hydroxyphenyl) propionic acid. DSPY contained significantly (P < 0.05) higher level of free polyphenols as indicated by higher bioaccessibility; however, the stability of the polyphenols and their fermentation products from DSPY were similar to that of DSP alone. These data would be useful in product developments incorporating DSP as a source of polyphenols in food products.     

Hydroxymethylfurfuraldehyde and amylase contents in Australian honey

The quality of Australian honey samples (processed and unprocessed) was assessed using HPLC techniques. 5-Hydroxymethylfurfuraldehyde (HMF) was used as the main quality indicator. Sampling included four commercially-processed honeys (Australian rainforest, Beechworth, Homebrand and Leabrook) and three unprocessed (Banksia, Grey box and Mallee). All honey samples, except Leabrook and Beechworth, showed an initial HMF content less than the Codex Alimentarius and International Honey Commission standard (40 mg/kg). HMF contents in Leabrook and Beechworth were 50.8 ± 1.34 and 74.9 ± 2.34 mg/kg, respectively. Heating unprocessed honey at 85 °C for 2 min caused significant (p ? 0.05) increment in HMF contents. The amounts of HMF in Mallee samples increased from 34.0 ± 0.31 to 42.3 ± 0.37 mg/kg after 2 min at 85 °C. All honey samples showed amylase activity above the minimum limit (8 Gothes). The physiochemical properties of honey showed significant variations among samples. The results revealed also that heating was not the only factor influencing HMF formation in honey, but also honey composition, pH value and floral source can contribute to these variations. Consequently, the amount of HMF may be an insufficient sole indicator of honey quality.     

Microbial,physico‐chemical and sensory characteristics of mango juice‐enriched probiotic dairy drinks

This study aimed to determine whether mango juice can improve the viability of probiotics in a fermented dairy‐based beverage whilst maintaining its quality characteristics. Formulations containing Lactobacillus acidophilus La‐5 culture, whole cow's milk and varying concentrations of mango juice (0%, 10%, 20%, 30% and 40% (w/w)) were produced and stored for five weeks at 4 °C. Results showed that probiotic viability was enhanced with the addition of 10% mango juice. Additionally, this formulation improved probiotics tolerance when exposed to in vitro gastrointestinal digestion. According to the sensory analysis, beverage sensory scores improved as levels of mango juice increased from 20% to 40%.     

Probiotics in Goat Milk Products: Delivery Capacity and Ability to Improve Sensory Attributes

Dairy foods, particularly those of bovine origin, are the predominant vehicles for delivery of probiotic bacteria. Caprine (goat) milk also possesses potential for successful delivery of probiotics, and despite its less appealing flavor in some products, the use of goat milk as a probiotic carrier has rapidly increased over the last decade. This review reports on the diversity, applicability, and potential of using probiotics to enhance the sensory properties of goat milk and goat milk‐based products. A brief conceptual introduction to probiotic microorganisms is followed by an account of the unique physicochemical, nutritive, and beneficial aspects of goat milk, emphasizing its advantages as a probiotic carrier. The sensory properties of probiotic‐enriched goat milk products are also discussed. The maintenance of probiotic viability and desirable physicochemical characteristics in goat milk products over shelf life is possible. However, the unpleasant sensory features of some goat milk products remain a major disadvantage that hinder its wider utilization. Nevertheless, certain measures such as fortification with selected probiotic strains, inclusion of fruit pulps and popular flavor compounds, and production of commonly consumed tailor‐made goat milk‐based products have potential to overcome this limitation. In particular, certain probiotic bacteria release volatile compounds as a result of their metabolism, which are known to play a major role in the aroma profile and sensory aspects of the final products.     

Encapsulation increases the in vitro bioaccessibility of probiotics in yoghurt

This study examined the encapsulation efficacy of probiotics in yoghurts, product physicochemical properties, the best timing to add encapsulated probiotics during yoghurt manufacturing (before or after fermentation) and their in vitro bioaccessibility. Three different yoghurt types were produced including plain and with encapsulated probiotics added before and after fermentation. A significant (P < 0.05) reduction in total probiotic count was observed in yoghurts containing encapsulated probiotics after 21 days of refrigerated storage. However, the total probiotic count increased during the in vitro colonic fermentation when yoghurts containing encapsulated probiotics were used, indicating increased bioaccessibility of probiotics in the colon.