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Summary: This study investigated the effect of fermentation by Lactiplantibacillus plantarum 75 (L75) on the physicochemical properties, survival of L75, sensory, antioxidants and their activities in leaf smoothies of six sweet potato cultivars [Orange‐fleshed (OFSP): 'Bophelo', and 'Beauregard'; cream‐fleshed (CFSP): 'Blesbok' and 'Ndou'; and purple‐fleshed (PFSP): '08.21p' and 'Purple‐purple']. Fermentation significantly affected the physiochemical properties. Fermentation for 24 h improved the carotenoid (TCC), ascorbic acid (AA) (6.8, 6.0 mg 100 g−1) and total phenolic (4435 mg 100 g−1) significantly in, 'Bophelo' smoothies. Whilst 48 h fermentation significantly increased the TCC, AA, organic acids, valine and alanine levels in 'Blesbok' smoothies'. Principal component analysis separated the unfermented 'Bophelo' and Purple‐purple' leaf smoothies from fermented leaf smoothies of OFSP, CSFP, and PFSP. DPPH scavenging activity and alpha‐carotene were effective markers for separating fermented from unfermented leaf smoothies in the variable importance study. Survival of L75 was influenced by fermentation duration and cultivar type. Fermented and unfermented smoothies were equally acceptable. [ABSTRACT FROM AUTHOR]

Summary: An orange‐coloured carrot pectin‐enriched fraction (CPEF), with 50% uronic acids (42%‐methylated), carrying lipophilic carotenoids and α‐tocopherol, developed homogeneous calcium‐crosslinked films at 0%, 25%, 50%, 75% and 100% CPEF proportions regarding a commercial pectin. CPEF gave higher relative elongation at break (65% for 50% CPEF film) when compared to 0% CPEF film (26% elongation). FTIR spectra showed a decreased intensity in the C = O group of the esterified carboxylate band as the CPEF content increased. CPEF maintained the orange colour (a* ≈ +37) and partly the carotenes (k ≈ 8.62 × 10−3 d−1) in films, even under 25 °C light storage. Also, CPEF gave water resistance to dissolution (100% CPEF film: 50% solubility), maintaining film integrity after 24 h soaking. Surface wettability decreased (40° contact angle) when CPEF proportion increased. These characteristics made the 100% CPEF film an efficient antioxidant interface that preserved a vegan cashew ripened cheese of high water activity (0.952) for 60 days at 7 °C, as determined through the assay of thiobarbituric acid‐reactive substances (TBARS). [ABSTRACT FROM AUTHOR]

Summary: Chemical composition, polyphenols, flavonoids, carotenoids and antioxidant activities of twenty‐five cultivars of sweet potato were investigated. Starch, crude protein, crude fat, total dietary fibre, reducing sugar and ash contents ranged between 51.88–69.21, 2.36–7.79, 0.24–1.11, 5.02–14.35, 1.07–9.78 and 1.95–4.29 g per 100 g dry weight (DW), respectively. Cultivars of Longshu, Pushu 32 and Qinshu No.7 (Shanxi province) displayed the highest values in total polyphenol contents (9.38, 9.11 and 8.76 mg GAE per g DW, respectively), Huangmeigui showed higher flavonoids content (2.54 mg RE per g DW), Xiangshu presented higher anthocyanin content (1.02 mg per g DW), whereas Pushu 32 had the highest β‐carotene content (208.11 μg per g DW). Strong significant positive correlations were presented between antioxidant activities and total polyphenol and flavonoid contents, indicating that polyphenols and flavonoids are essential antioxidants in sweet potatoes. Among all cultivars, Pushu 32 presented the highest grey relational grade (GRG) value (0.7811), suggesting its importance as a healthy diet. [ABSTRACT FROM AUTHOR]

Summary: To have a better understanding of regulatory mechanism of carotenoid accumulation in sweetcorn (Zea mays L.), we analysed carotenoid profiles, expression patterns of carotenogenic genes and antioxidant activities in two genotypes of sweetcorn during kernel development. The results suggested that the expression of carotenogenic genes played an essential role in carotenoid accumulation and higher expression levels of carotenogenic genes obviously led to higher levels of total carotenoids. It was found that the expression of upstream genes (ZmPDS,ZmZDS and ZmCRTISO) had major influence on the content of total carotenoid during kernel development. The accumulation of lycopene was closely related to the coordination of upstream and downstream genes. The expression of ZmHYD and ZmZEP was influential on zeaxanthin accumulation, which was also influenced by the rate of ZmCHYB/ZmCHYE. Expression levels of ZmCHYE were still stable in order for α‐xanthophylls largely accumulated during kernel development. Lutein, zeaxanthin, α‐cryptoxanthin and β‐cryptoxanthin constituted the predominant carotenoids in sweetcorn. Two essential stages for carotenoid accumulation were found in sweetcorn during kernel development. [ABSTRACT FROM AUTHOR]

Investigations were carried out to study the influence of the formulation on the drying characteristics and the final quality of foam-mat-dried uvaia pulp powder, such as total phenolic content, carotenoids and antioxidant activity. Two formulations were developed (one with 3.5% albumin (Alb.), 0.25% carboxymethylcellulose ( CMC) and 0.25% xanthan gum ( XG), and the other containing only 7% albumin) and dried at 60 and 70 °C. Drying kinetics showed only a falling rate at both temperatures and formulations. Mathematical models were fitted to the experimental data to describe the drying kinetics. The Page model provided the best description of the foams. The higher temperatures reduced the drying time and increased the effective diffusivity. Compared with the fresh pulp, the uvaia powder at 70 °C exhibited decreased antioxidant activity, total phenolics and carotenoids contents. [ABSTRACT FROM AUTHOR]

Grapefruit juice was investigated using pulsed electric fields ( PEF) with (electric field strengths: 0, 5, 10, 15, 20 and 25 kV cm−1; flow rate: 80 mL min−1; pulse frequency: 1 kHz at 40 °C for 600 μs). Total phenolics, DPPH, total antioxidant capacity ( TAC), total anthocyanins, total carotenoids, sugars and physicochemical properties of grapefruit juice were studied. In addition, the effect of PEF treatment on micro-organisms was also observed. Results indicated that no significant change was observed in pH, Brix, titratable acidity, sugars, total anthocyanins and colour attributes with the increase in pulsed electric strength as compared to control treatment. However, significant decrease in nonenzymatic browning ( NEB) and viscosity while an increase in cloud value, DPPH, TAC, total phenolics and total carotenoids, while reduction in the activity of micro-organisms, was also observed with the increase in pulsed electric strength as compared to control treatment. This study suggested that PEF at 25 kV cm−1 could improve the quality of grapefruit juice. [ABSTRACT FROM AUTHOR]

Red guava ( Psidium cattleyanum Sabine) and guabiju ( Myrcianthes pungens (O. Berg) D. Legrand) are small fruits that are native to southern Brazil. This study evaluated the physicochemical composition, antioxidant activity and functional compounds of both fruits. Red guava exhibited a large amount of dietary fibre. Guabiju showed more antioxidant activity, had a higher anthocyanin content and had a higher carotenoid content. In the guabiju fruit, β-carotene represented 40.4% of the total carotenoids, and malvidin 3-glycoside represented 60% of the total anthocyanin content. β-Cryptoxanthin was the predominant carotenoid in red guava, representing 44.8% of the total carotenoids; cyanidin 3-glycoside was the predominant anthocyanin, representing 51.7% of the total anthocyanins. These native fruits could represent an alternative to traditionally consumed fruits, and then, the characterisation of bioactive compounds of fruits such as red guava and guabiju represents important information to the consumers who looking for a healthy diet. [ABSTRACT FROM AUTHOR]

The aim of this work was to determine the enzymatic activities of catalase ( CAT), superoxide dismutase ( SOD) and ascorbate peroxidase ( APX) together with the total phenolic and carotenoid contents and antioxidant capacity of two cultivars of cactus stems under modified atmosphere packaging containing a passive atmosphere, an active (with N2) atmosphere and control (unsealed polyurethane trays) all stored at 4 ± 1 °C. Results indicated that Atlixco cultivar cactus stems had a shelf life that was twice as long (20 days) than that of Milpa Alta cultivar under N2 MAP. The total enzyme activities of SOD, APX and CAT as well as the carotenoid content were higher in Atlixco than in Milpa Alta. The antioxidant enzymatic and non-enzymatic systems as well as the antioxidant capacity and the phenolic content retention determined in Atlixco cactus stems under N2 MAP appear to explain the longer postharvest life of this cultivar. [ABSTRACT FROM AUTHOR]

Light red tomatoes were exposed to different doses of ultraviolet C (UV-C) irradiation (1.0, 3.0 and 12.2 kJ m−2). After treatment, the tomatoes were stored for 2 days at room temperature, and then analysed to determine the effect of irradiation on the main antioxidants, carotenoids and phenolic compounds and the results compared with the control samples. The lycopene content was found to have increased by 14% with respect to the control samples, while β-carotene decreased. Cis-isomers from lycopene also increased when the tomatoes were exposed to irradiation for more than 3 h. UV- C irradiation also had a positive effect on total phenolic compounds; however, the same effect was not observed in the individually analysed phenolic compounds. While chlorogenic and ferulic acids increased in content, naringenin and rutin contents decreased. These results suggest that UV- C irradiation of tomatoes could improve the beneficial effect of red tomatoes for human health by increasing the levels of certain bioactive compounds; it could also be used to obtain higher content of bioavailability components, such as cis-isomers from lycopene. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of microfiltration on the lycopene content and antioxidant capacity of watermelon juice using ceramic membranes with an average pore size of 0.1 μm and a permeable area of 0.022 m2. The influence of the tangential cross-flow velocity (4.3-6.4 m s−1) and temperature (23-37 °C) on the permeation flux, lycopene content and antioxidant capacity was evaluated. A 22 complete factorial experimental design was used. Increases in tangential cross-flow velocity and temperature had positive effects on permeation flux, with a maximum of 92.4 l h−1 m−2 achieved at 6.4 m s−1 and 30 °C. With regard to the lycopene content and antioxidant capacity, tangential cross-flow velocity was the only factor that exhibited significant effects on these responses. For the most concentrated extract, the lycopene concentration and antioxidant capacity were enhanced by 402.8% and 416.3%, respectively. [ABSTRACT FROM AUTHOR]

Summary Retention of bioactive compounds in white- (WFP), yellow- (YFP), red- (RFP) and purple (PFP)-fleshed potatoes after drum-drying (DD) and Refractance Window™ drying (RW) was compared with freeze-drying (FD). Processing, generally, did not influence total phenolics. Total carotenoid was high in YFP, but decreased with DD. Both DD and RW decreased lutein concentration in YFP. The RFP and PFP had the highest total anthocyanin, and their concentrations were decreased by DD. RW decreased total anthocyanin in PFP only. Total antioxidant activity in WFP was higher with DD but lower with RW. In contrast, DD and RW drying had no significant effect on total antioxidants in YFP, RFP and PFP. Therefore, drying generally decreased antioxidants, with FD and RW retaining the highest concentration of bioactive compounds. [ABSTRACT FROM AUTHOR]

Summary The effects of organic farming, pasteurisation and addition of β-cyclodextrin on the content of vitamin C, colour, carotenoids and antioxidant capacity of orange juices were studied. After pasteurisation at 98 °C (20 s) and subsequently storage along 145 days at room temperature (20-25 °C), the loss of vitamin C content was around 30%. The effects of the thermal process on carotenoid were clearly observed in lutein (loss of 16% for organic and traditional 8%) and especially β-cryptoxanthin (loss of 30%). The colour changes were noticeable after the pasteurisation of orange juice and subsequent storage, with significant decreases being observed in lightness and the coordinate a*, while increases were found for coordinates b*, Hue* and chroma. The antioxidant capacity was 0.075 ± 0.01 and 0.053 ± 0.01 mMT mL−1 for organic and conventional, respectively, with losses around 40% being found at the end of the storage period. The addition of β-cyclodextrin caused no significant effects on the parameters under analysis. These data showed that strong thermal treatments, such as pasteurisation, adversely affect the nutritional and sensory quality of orange juices. [ABSTRACT FROM AUTHOR]

Summary Pollen is characterised for having a low fat content, a relatively high content of dietary fibre and an important amount of minerals and essential amino acids. With regard to bioactive compounds, honeybee-collected pollen exhibits an important source of phytochemical compounds and antioxidant activity. The purpose of this research was to study how the nutritional properties and the stability of the bioactive compounds found in honeybee-collected pollen were affected by the commercial processing and its floral origin. To achieve this goal, pollen pellets of different floral origin were harvested directly from hives and immediately stored at −80 °C. Pollen pellets were dried by placing them into hot-air chambers (traditional drying methodology) or by means of freeze-drying. We found a slight influence of floral origin on the nutritional properties of pollen pellets (multifloral pollen had higher contents of fat, carbohydrates, proteins and mineral elements than monofloral-type pollen), whereas the abundance of bioactive compounds was correlated with the origin factor as well as the methodology employed to dry the fresh pollen pellets, especially carotenoid pigments such as lutein (5.73 ± 1.80, 4.93 ± 1.16 and 0.81 ± 0.16 μg of lutein per g of pollen for fresh, lyophilised and hot-air-dried multifloral pollen). [ABSTRACT FROM AUTHOR]

The contents of total chlorophyll (T-Chl), carotenoids and phenolics compounds were quantified in the biomasses of Ulva lactuca grown either in normal or artificial sea water under indoor conditions. The antioxidant and antibacterial activities of U. lactuca crude organic extracts ( Ulva-COEs) were determined. Thirty-four compounds in Ulva-COEs were characterised by thin layer chromatography and high-performance liquid chromatography. The major compounds were chlorophyll a (Chl a) (15.60–30.90%) and b (Chl b) (12.20–14.89%) , 9-cis β-carotene (13.12–14.47%), α-carotene (11.44–11.47%) and all-trans β-carotene (6.16–29.70%, of total carotenoids).The Ulva-COEs exhibited remarkable antioxidant activity, with an IC50 (concentration which causes a 50% of DPPH radical scavenging activity) values ranged from 16.5 and 18.7 μg mL−1, which could be compared with the synthetic antioxidants: α-tocopherol (14.4 μg mL−1), butylated hydroxyanisol (13.1 μg mL−1) and butylated hydroxyltoluene (13.1 μg mL−1). Also, Ulva-COEs exhibited great potential antibacterial activities against six bacterial strains, with minimal inhibitory concentration values ranged from 0.40 to 0.35 mg mL−1. [ABSTRACT FROM AUTHOR]

The influence of washing treatment on the retention of key antioxidants in minimally processed iceberg lettuce was examined. Shredded iceberg lettuce was subjected to one of three washing treatments: a domestic wash (tap-rinsed), immersion in distilled water (water-dipped) or immersion in chlorinated water (chlorine-dipped). Lettuce was subsequently packed in oriented polypropylene bags and flushed with 100% nitrogen and stored at 4 °C. Vitamin C (ascorbic acid and dehydroascorbic acid), total phenols, total antioxidants, individual phenols, individual carotenoids, colour measurements and pH were quantified on production day and throughout the storage period (8 days). Different groups of antioxidants were found to differ in their response to washing treatments. No significant ( P > 0.05) effects of washing treatment were observed on total antioxidant activity, total phenolics and on the levels of individual phenolics (chicoric acid, chlorogenic acid and caffeic acid). Individual carotenoids were initially affected by washing treatment, with higher levels of lutein and beta-carotene retained with domestic washed lettuce. Ascorbic acid was the antioxidant most affected by washing treatments with domestic washing resulting in significantly ( P ≤ 0.05) higher retention of ascorbic acid throughout the storage period compared with the chlorine-dipped lettuce. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the antioxidant properties, including phenolics, ascorbic acid and carotenoids of four green asparagus ( Asparagus officinalis L.) spears cultivars (UC 157, AM 822, Gijnlim, and Grande) grown under greenhouse conditions and to asses their changes during cooking process. The highest spear production of category ‘extra’ and ‘first’ was recorded on ‘UC 157’, whereas the higher production of “second” class spears was recorded on ‘UC 157’ and ‘Gijnlim’. The Grande cultivar has provided a higher total phenol, quercetin, rutin and lutein + zeaxantin contents in comparison to ‘UC 157’, ‘Gjinlim’ and ‘AM 822’ cultivars. The results also indicate that the effect of cooking process was significant and more pronounced than the effect of cultivars. The cooking process increased the antioxidant activity, total phenols, quercetin, rutin, β-carotene and lutein + zeaxantin contents by, 16%, 23%, 98%, 32%, 24% and 25%, respectively, but decreased the total ascorbic acid content by 52%. [ABSTRACT FROM AUTHOR]

Banana is one of the most important tropical fruits, and India ranks first in its world production. Banana cultivars rich in provitamin A carotenoids may offer a potential food source for alleviating vitamin A deficiency, particularly in developing countries. With a view to exploit banana peels as a source of valuable components, in the present study, proximate composition, carotenoids, beta-carotene and some anti-oxidative enzymes as well as carbohydrate content of selected Indian banana varieties were determined. Karpooravalli cultivar of banana showed the maximum accumulation of carotenoid content in the non-edible (68 μg g−1 d.w.) portion of banana, while being the second highest in beta-carotene content (143.12 μg per 100 g). However, Red Banana ranked highest in total carotenoid contents for pulp (4 μg g−1 d.w.) and beta-carotene was estimated to be the highest in the case of peels (241.91 μg per 100 g) and in pulp (117.2 μg per 100 g). Karpooravalli cultivar of banana is also rich in carbohydrate content in terms of total starch (1786.0 μg g−1 d.w. in peels and 544.85 μg g−1 d.w. in pulp) and sugars (53.53 μg g−1 d.w. in peels and 39.05 μg g−1 d.w. in pulp). The catalase enzyme activity in these peels ranged from 5.66 to 35.57 nmol min−1 mg−1 proteins and was found at a higher level in cultivar Poovan, while the ascorbate peroxidase showed the range of 2.25 to 6.22 μmol min−1 mg−1 proteins. The peels of cultivars Red Banana and Karpooravalli are rich source of bioactive compounds, such as carotenoids (beta-carotene), anti-oxidative enzymes and carbohydrate contents. [ABSTRACT FROM AUTHOR]

Carotenoids, total phenolics and anti-oxidant activity of carrots were determined during 6 months of storage at 0 °C, 85–90% relative humidity. In addition to changes in CIE colour parameters (L*, a*, b*, h and C), physicochemical properties of carrots including water soluble solids; pH and titratable acidity were evaluated. Cold storage of carrots did not affect the carotenoid levels (β-carotene, α-carotene and total carotenoid) except lutein, which showed a 37.5% loss. Total phenolic concentration of carrots decreased significantly ( P < 0.05) over the entire storage period. The anti-oxidant activity of carrots decreased with a level of 31% and was found correlated with total phenolics and lutein content in carrots. While CIE L* and a* parameters decreased significantly ( P < 0.05) after 6 months of storage, the b* and C parameters were statistically unchanged for the first 4 months of storage, but decreased gradually for the following period. [ABSTRACT FROM AUTHOR]

Eleven peach cultivars (white- and yellow-flesh peaches, nectarines and canning clingstone peaches) were assayed for their antioxidant capacity and their content of some important organic compounds as well as vitamin C, carotenoids and phenols. Antioxidant capacity, determined by FRAP assay, varied between genotypes. Those with the highest value of Ferric Reducing Antioxidant Power (FRAP) were Federica and Springcrest. Antioxidant capacity was correlated to the amount of organic components with significant differences among the cultivars. In some case, antioxidant capacity was related to phenol content, as in yellow–flesh peaches. These results suggest the importance of genotype for determining antioxidant capacity, which, in turn, is related to the organic constituents, such as phenols, vitamin C and carotenoids. [ABSTRACT FROM AUTHOR]

Five different coloured sweet peppers ( Capsicum annuum cv. Signal), white, green, yellow, orange and red were analysed for total carotenoids, α-tocopherol, sugars (glucose, fructose and sucrose), organic acids (citric and ascorbic acids) and anti-oxidant properties. The mature fruits, ‘Signal Red’, ‘Signal Orange’ and ‘Signal Yellow’ contained higher carotenoids, α-tocopherol, sugars and organic acids than the immature fruits, ‘Signal Green’ and ‘Signal White’. Among the mature fruits, ‘Signal Red’ was the highest in total carotenoids [9.15 mg (100 g)−1 of fresh weight] while ‘Signal Orange’ was the highest in α-tocopherol [5.40 mg (100 g)−1 of fresh weight]. ‘Signal Red’ and ‘Signal Orange’ contained the most sugars and organic acids. The suppression of 2,2′-azobis (2,4-dimethylvaleronitrile) (AMVN)-induced oxidation of methyl linoleate by the acetone extracts from the coloured sweet peppers resulted as follows: ‘Signal Red’ > ‘Signal Orange’ ≈ ‘Signal Yellow’ > ‘Signal Green’ ≈ ‘Signal White’. The order of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of the acetone extracts was similar to that of suppression of methyl linoleate oxidation. [ABSTRACT FROM AUTHOR]

Some of the most exciting research in the last decade has been the discovery of a group of nutrients, which have protective effects against cell oxidation. These naturally occurring compounds impart bright colour to fruits and vegetables and act as antioxidants in the body by scavenging harmful free radicals, which are implicated in most degenerative diseases. Epidemiological studies have established a positive correlation between the intake of fruits and vegetables and prevention of diseases like atheroscelerosis, cancer, diabetes, arthritis and also ageing. So pronounced has been their effect on ageing that they have been called ‘fountains of youth’. Fruits and vegetables have thus had conferred on them the status of ‘functional foods’, capable of promoting good health and preventing or alleviating diseases. Phenolic flavonoids, lycopene, carotenoids and glucosinolates are among the most thoroughly studied antioxidants. The present review highlights the potential of fruits and vegetables rich in antioxidants, their health benefits and the effect of processing on the bioavailability of these nutrients. The paper also reviews some of the important methods used to determine the antioxidant activity. [ABSTRACT FROM AUTHOR]