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Background: Photo-selective coloured netting is referred to as a 'new agro-technological' concept adopted to manipulate light quality changes that can induce favourable responses in plants., Results: Tomato (Solanum lycopersicum L.) cultivars AlvaV, Irit and SCX 248 grown under the black net (commercial net, 25% shading) showed higher weight loss, loss of firmness, ascorbic acid content and decline in the ratio of soluble solids content/titrable acidity during post-harvest storage (low-temperature storage at 10°C and 90% relative humidity for 21 days followed by market shelf conditions at 25°C for 2 days). During post-harvest storage, lycopene, β-carotene, total phenolic content and antioxidant scavenging activity were higher in cvs AlfaV and Irit grown under the black or pearl nets. However, the β-carotene, total phenolic content and antioxidant scavenging activity were higher in SCX 248 grown under the red net during post-harvest storage. Cultivar AlfaV grown under the red and pearl nets had a higher number of odour active aroma compounds during post-harvest storage. Panellists preferred cv. AlfaV grown under the pearl nets after storage based on taste, overall appearance and firm textured fruits., Conclusion: Pearl photo-selective nets retained the overall fruit quality and bioactive components in cvs AlfaV and Irit during post-harvest storage. Red photo-selective nets, however, showed greater influence on retention of overall fruit quality and bioactive compounds in cv. SCX 248 during post-harvest storage., (© 2013 Society of Chemical Industry.)

This study examined the impact of fermentation using Lactiplantibacillus plantarum (L75) and Bifidobacterium longum (BF) on the total soluble solids (TSS), pH, TA, LAB survival, color properties, ascorbic acid content, total phenolic content (TPC), carotenoid components, and antioxidant properties of smoothies made from melon varieties (Cantaloupe, Honeydew, and Watermelon) separately with pumpkin leaves (Cucurbita moschata and Cucurbita pepo). For all smoothies, pH (r = −0.74) and TSS (r = −0.79) were inversely and strongly correlated with LAB counts, while LAB counts were positively correlated with TA (r = 0.87). Fermentation time (24 to 72 h) significantly (p < 0.05) decreased the TSS (%), pH, and color properties of all smoothies fermented with L75 or BF, while TA increased. Fermenting Cantaloupe melon and C pepo leaves with L75 (CMCL75) for 24 h increased the ascorbic acid content to 3.8 mg/100 mL. The sensory panel scores were highest for Watermelon and C. moschata or C. pepo fermented with L75 or BF for 24 h. TPC concentration was highest in CMCL75 (70.76 mg of gallic acid per 100 mL) after 24 h. C. pepo leaves and Cantaloupe fermented with L75 (CPCL75) showed the highest concentration of total carotenoids (70.38 mg/100 mL), lutein (2.53 µg/100 mL), cis β-carotene (25.43 µg/100 mL), and trans β-carotene (620.37 µg/100 mL). In contrast, CMCL75 showed the highest concentration of zeaxanthin (0.70 mg/100 mL). This study demonstrated the potential of fermenting Cantaloupe and pumpkin leaves together with the L75 strain to produce non-dairy functional products. [ABSTRACT FROM AUTHOR]

The Spiny saltbush (Rhagodia spinscens) is a halophyte species with the potential to provide natural ingredients used in food and pharmaceutical industries. In food and pharmaceutical applications, drying is necessary to maintain shelf-life, which reduces phytonutrient content. In this study, changes in the nutritional composition, phenolic and carotenoid profiles of radical antioxidant scavenging activity [(2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)], antioxidant power [ferric reducing antioxidant ability assay (FRAP)], and cytotoxicity of freeze- and oven-dried (55 °C for 24 h) spiny saltbush were determined. Sodium (4.72 g/100 g dry weight (DW), potassium (6.86 g/100 g DW), calcium (4.06 g/100 g DW), zinc (372 mg/kg DW) and protein content were higher in oven-dried samples than freeze-dried samples. Ultra-performance liquid chromatography–mass spectrometry analysis detected 18 metabolites in saltbush extracts. Partial Least-Squares Discriminant Analysis, Hierarchical Cluster Analysis, and Variable Importance in Projection discriminated between freeze-dried and oven-dried samples. Freeze-dried samples retained more individual metabolites than oven-dried samples, while oven-dried samples had higher antioxidant activity (ABTS and FRAP), lutein, trans-β carotene, and cis-β-carotene. Correlation analysis identified potential antioxidant candidates between phenolic and carotenoid compounds. Neither freeze-dried nor oven-dried spiny saltbush samples showed cytotoxicity. The study uncovered changes in phytonutritional compounds after the oven and freeze-drying spiny saltbush, a potential salt alternative and functional ingredient for the food industry. [ABSTRACT FROM AUTHOR]

Summary: Co‐digestion of cantaloupe (C) melon fresh cuts (FC) coated with probiotics [Lactiplantibacillus plantarum 75/xanthan gum with Natal plum (NP)] or beetroot leaves (BL) was evaluated to determine their bioaccessibility of individual anthocyanins (cyanidin‐3‐glucoside, cyanidin‐3‐O‐sambubioside) and carotenoids (lutein, trans‐β‐carotene and cis‐β‐carotene). Co‐digestion of probiotic‐coated C‐melon‐FC with NP increased the percentage (%) bioaccessibility of cyanidin‐3‐glucoside (11.18%) and cyanidin‐3‐O‐sambubioside (8.89%) compared to single digestion of Natal plum. Bioaccessibility of lutein (18.2%), trans‐β‐carotene (36.92%) and cis‐β‐carotene (16.74%) increased when co‐digestion of probiotic‐coated C‐melon‐FC with BL compared to the single digestion of uncoated C‐melon. Co‐digestion of C‐melon‐FC‐L75 with BL showed the highest antioxidant activity. L. plantarum had the highest LAB survival at the intestinal phase (6.01–6.26 Log CFU mL−1) during single and co‐digestion showing probiotic potential. C‐melon‐FC‐L75, Natal plum and beetroot leaves could be recommended as functional ingredients in meal preparation. [ABSTRACT FROM AUTHOR]

Baby spinach is becoming increasingly popular as a salad ingredient and needs high fertiliser rates to grow well and attain higher-quality leaves (dark green leaves). Chemical fertilisers, especially nitrogen (N), boost yields. There are many risks associated with nitrogen fertilisation. Additionally, spinach contains phenolic compounds and carotenoids. Nitrogen fertilisation affects growth, development, yield and metabolites. This study examined the impact of lower concentrations of N (0, 30, 60, 90, 120, 150 mg/L) on yield and colour properties [light intensity (L*) colour coordinates, unique for green colour (a*) and yellow colour (b*)], as well as the impact of varying N concentrations on the total phenolic content and p-coumaric acid, quercetin, ferulic acid, kaempferol, lutein, zeaxanthin, β-carotene and antioxidant activities in the baby spinach varieties 'Acadia', 'Crosstrek' and 'Traverse', and it was established that N fertilisation improves phytochemical bioaccessibility and antioxidant activity. In a split strip plot design, three baby spinach varieties were treated with different N concentrations, including 0, 30, 60, 90, 120 and 150 mg/L. For 40 days, three baby spinach varieties were grown on soilless Mikskaar Professional substrate 300. During both seasons, 'Crosstrek' had the highest fresh mass (921.4 g/m2, 856.3 g/m2) at 120 mg/L N, while 'Traverse' had the highest fresh mass at 554.8 g/m2 and at 564.3 g/m2 at 90 mg/L N and did not differ significantly from 90 to 150 mg/L N during either season. During both seasons, 'Acadia' at 90 mg/L N increased fresh mass to 599 g/m2 and 557.9 g/m2. The variety × N supply interaction significantly affected the leaf colour; chlorophyll content across seasons; the levels of bioactive compounds, p-coumaric acid, quercetin, ferulic acid, kaempferol, lutein, zeaxanthin and β-carotene in spinach varieties; the in vitro bioaccessibility; and the antioxidant activity. Varietal differences influenced the bioaccessibility of phenolic compounds and carotenoid components. The appropriate N levels can be used during plant cultivation to optimise the bioaccessibility of this spinach variety. Thus, fertilising 'Traverse' with 90 mg/N mL increased the in vitro bioaccessibility of β-carotene (35.2%), p-coumaric acid (7.13%), quercetin (8.29%) and ferulic acid (1.92%) without compromising the yield. [ABSTRACT FROM AUTHOR]

Sweet potatoes (Ipomoea batatas) are highly profitable, contribute to food security, and their leaves rich in phytonutrients. This study examined the optimal leaf harvesting stage by harvesting newly formed leaves (leaves 1 to 5) to achieve the highest concentration of carotenoids, phenolic compounds, antioxidant properties and mineral content. Leaves of five purple-fleshed sweet potato genotypes '2019-11-2' and '2019-1-1', 'Purple-purple', and from the USA '08-21P' and '16-283P' were harvested based on tuber life cycle [vegetative 8 weeks after planting (VS-8WAP), tuber initiation (TIS-12WAP), and tuber maturation phases (TMS-16WAP)]. At the 8WAP stage, leaves of genotype '2019-11-2' had the highest concentrations of cyanidin-caffeoyl-sophoroside-glucoside (17.64 mg/kg), cyanidin-caffeoyl-feruloyl-sophoroside-glucoside (41.51 mg/kg), peonidin-caffeoyl-hydroxybenzoyl-sophoriside-glucoside (45.25 mg/kg), and peonidin caffeoyl-feruloyl-sophoriside-glucoside (24.47 mg/kg), as well as antioxidant scavenging activity. In contrast, 'Purple-purple' harvested at TIS-12WAP showed the highest concentration of caffeoylquinic acid derivatives. Zeaxanthin, lutein, all trans-β-carotene, and cis-β-carotene are the most abundant carotenoids in genotype '08-21P' at VS-8WAP. As a result, local genotypes '2019-11-2' harvested at 8WAP and 'Purple-purple' harvested at 12WAP are potential sources of anthocyanins and caffeoylquinic acid derivatives. Conversely, USA's genotype '08-21P' at the VS-8WAP stage is an excellent source of carotenoids. The leaves of USA's '08-21P' genotype and the local '2019-11-2' genotype at TMS-16WAP exhibited the highest content of Fe and Mn, respectively. The study identified the optimal leaf stage for consumption of leaves and for use as a functional ingredient. [ABSTRACT FROM AUTHOR]

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]

This study investigated the effects of Lactiplantibacillus plantarum 75 (LAB 75) fermentation at 37 °C for 48 h on the pH, total soluble solids (TSS), colour, total titratable acidity (TTA), carotenoids, and bioactivities of cowpea leaf smoothies from three cultivars (VOP 1, VOP 3, and VOP 4). Fermentation reduced the pH from 6.57 to 5.05 after 48 h. The TTA increased with the fermentation period, whilst the TSS reduced. Fermentation of the smoothies resulted in the least colour changes (∆E) in VOP 1 after 48 h. Fermentation of cowpea smoothies (VOP 1, VOP 3, and VOP 4) improved the antioxidant capacity (FRAP, DPPH, and ABTS), which was attributed to the increase in total phenolic compounds and carotenoid constituents in all of the fermented cowpea smoothies. VOP 1 was further selected for analysis due to its high phenolic content and antioxidant activity. The VOP 1 smoothie fermented for 24 h showed the lowest reduction in TPC (11%) and had the highest antioxidant (FRAP, DPPH, and ABTS) activity. Ltp. plantarum 75 was viable and survived the harsh conditions of the gastrointestinal tract, and, hence, could be used as a probiotic. VOP 1 intestinal digesta showed significantly higher glucose uptake relative to the undigested and the gastric digesta, while the gastric phase had higher levels of α-amylase and α-glucosidase compared to the undigested samples. [ABSTRACT FROM AUTHOR]

Summary: Traditionally, cowpea (Vigna unguiculata) leaves are consumed by the sub‐Saharan population. Carotenoids and phenolic compounds in cowpea leaves possess great antioxidant properties; however, their bioaccessibility is affected by digestion. This study investigated the influence of in vitro digestion on carotenoids, antioxidant and antidiabetic capacity of three cowpea cultivars (VOP1, VOP3 and VOP4). Among the cowpea cultivars, VOP1 showed the highest 9‐cis‐β‐carotene (21.13%) bioaccessibility, VOP3 showed the highest all‐trans β‐carotene (32.11%) and α‐carotene (21.75%) bioaccessibilities and VOP4 showed the highest lutein (17.70%) and zeaxanthin (32.03%) bioaccessibilities. The ferric‐reducing antioxidant power, 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging (DPPH) activities, 2,2′‐azino‐bis‐3‐ethylbenzthiazoline‐6‐sulphonic acid), α‐amylase and α‐glucosidase inhibitory effects decreased in the small intestinal phase. The cowpea cultivars demonstrated a high ability to meet the recommended daily allowance for carotenoids. As a result, the findings of this study show that cowpea leaves have the potential to be used as functional ingredients. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the bioaccessibilities of total phenolic compounds, carotenoid profile, antioxidant activity, and Lactic acid bacteria (LAB) survival in fermented mango juice (MJs) obtained from three mango cultivars after exposure to an in vitro gastrointestinal digestion model. The MJs from three cultivars ('Sabre', 'Peach', and 'Tommy Atkins') were fermented using Lactiplantibacillus plantarum 75 (L75), Leuconostoc pseudomesenteroides 56 (L56), and their combination (L56 + 75). Fermented MJs were digested and fractions: gastric (GF), intestinal (IF), and dialysis (DF) were analyzed for total polyphenolic content (TPC), antioxidant activity (FRAP), 1-diphenyl-2-picrylhydrazyl (DPPH), and 2.2-azinobis-3-ethyl-benzothiazoline–6-sulfonic acid (ABTS). In addition, the carotenoid content and the LAB population were determined from the GF and IF. After digestion, TPC decreased while fermentation improved its bioaccessibility. L75-fermented 'Sabre' MJs had the highest bioaccessible TPC in the GF (75.65%), IF (50.10%), and DF (32.52%) while L56 'Peach' MJs increased the β-carotene bioaccessibility by 1.32-fold at GF and IF (1.21-fold). When compared to the other two juices, 'Sabre' and 'Peach' MJs fermented with L75 showed the highest IC50 values for DPPH and ABTS. Generally, L75-fermented 'Sabre' MJs had the highest LAB survival at both GF (7.57 Log CFU/mL) and IF (7.45 Log CFU/mL) and hold potential as probiotic juices. L56-fermented 'Sabre' MJs would ensure the delivery of four times the carotenoid recommended dietary allowance (RDA) to a target site in the body while L75-fermented 'Peach' MJs could be used to effectively counteract oxidants in the body system. [ABSTRACT FROM AUTHOR]

Prior to consumption, African pumpkin leaves (Momordica balsamina L.) are generally cooked. In this study, the effects of common household cooking methods (boiling, steaming, microwaving, stir-frying) on bioactive metabolites, carotenoids, antioxidant activity, antinutrients and inhibitory effects on α-glucosidase and α-amylase activities were examined. A set of 14 bioactive metabolites were identified in raw and cooked African leaves using UPLC-QTOF/MS. The results showed that the four different types of household cooking methods had different effects on the bioactive metabolomics profile of African pumpkin leaves. In comparison to raw leaves and leaves cooked in other methods, the concentrations of six phenolic compounds, rutin, cryptochlorogenic acid (4-caffeoylquinic acid), pseudolaroside A, isorhamnetin 3-O-robinoside, quercetin 3-galactoside, and trans-4-feruloylquinic acid, were highest in stir-fried leaves. Of all household cooking methods tested, stir-frying increased the content of lutein, β-carotene, and zeaxanthin by 60.00%, 146.15%, and 123.51%, respectively. Moreover, stir-frying African pumpkin leaves increased the antioxidant activity (DPPH and ABTS) and the inhibition of α-glucosidase and α-amylase. Compared to all four methods of household cooking, stir-frying reduced the antinutritive compounds compared to raw leaves. This work provides useful information to the consumers on the selection of suitable cooking methods for African pumpkin leaves. [ABSTRACT FROM AUTHOR]

Preharvest application of plant growth regulators may have promise to improve product shelf-life. The study examined effects of the plant growth regulators [naphthalene acetic acid (NAA), the seaweed concentrate Kelpak®, and their combination] on postharvest quality of yellow sweet pepper (Capsicum annuum L.) grown in soilless culture. Seedling root plugs were soaked in Kelpak® at 10 mL∙L−1, 3 h before transplanting. Thereafter, solutions applied to foliage until runoff were: NAA at 20 mg∙L−1 and Kelpak® at 5 mL∙L−1 at 15, 30 and 45 days after transplanting. Sweet peppers were harvested at maturity, and stored at 7.5ºC for 0, 7, 14, or 21 days (d). The individual Kelpak® and NAA applications minimized weight loss and color degradation during storage. All treatments helped retain firmness and tissues had higher pH compared to the control. Application of NAA+Kelpak® favored accumulation and retention of total soluble solids until 14 d of storage. Fruit treated with Kelpak® and NAA+Kelpak® had higher ascorbic acid content than all other treatments. Application of NAA+Kelpak® helped retain higher carotenoid content. The NAA, Kelpak®, and their combination, enhanced accumulation of total phenols over time with minimal impact on antioxidant power (FRAP activity). The NAA and Kelpak® preharvest application can improve quality of yellow sweet pepper during postharvest storage up to 7 d. [ABSTRACT FROM AUTHOR]

Cowpea is a well-known nutrition rich African leafy vegetable that has potential to sustain food and nutrition insecurity in sub-Saharan Africa. Consumption of cowpea legumes is associated with reduced risk of type 2 diabetes mellitus. Therefore, the present study was designed to evaluate the (i) variation in phenolic metabolites in seven cowpea cultivars (VOP1, VOP2, VOP3, VOP4, VOP5, VOP7, and VOP8 using UHPLC coupled with high resolution Q-TOF-MS technique, (ii) in vitro antioxidant activity using ferric reducing/antioxidant capacity (FRAP) assay (iii) in vitro anti-diabetic effects and (iv) composition of carotenoids and amino acids of theses cowpea cultivars. The results of this study demonstrated that gentisic acid 5-O-glucoside, quercetin 3-(2G-xylosylrutinoside) and Quercetin 3-glucosyl-(1->2)-galactoside were highest in VOP1 VOP4 and VOP5, respectively. High inhibition (>50%) of α-glucosidase and α-amylase activities was shown by the leaf extracts (50 and 25 mg/mL) of VOP1 and VOP4. Cowpea cultivars VOP1 and VOP4 demonstrated the highest gene expression levels of regulation of glucose transporter GLUT4 in C2C12 skeletal muscle cells, similar to insulin. A positive correlation exited between the phenolic components and the inhibitory effect of antidiabetic enzymes and FRAP activity. Cytotoxic effect was not detected in vitro in any cowpea cultivar. Lutein (124.6 mg/100 g) and all-trans-beta-carotene (92.6 mg/100 g) levels were highest in VOP2 and VOP1, respectively. Cowpea cultivars VOP3 and VOP4 showed potential to fulfil the daily requirements of essential amino acids. Thus, based on this information, cowpea (leaves) genotypes/cultivars can be selected and propagated for the further development of supplementary foods or functional food ingredients. [ABSTRACT FROM AUTHOR]

A green pre-treatment approach, microwave (MW) and ultrasound (US), along with drying methods [hot air (HA) and freeze-drying (FD)], was assessed for colour properties, phenolics, carotenoid components and antioxidant activity DPPH, ABTS, FRAP assays of three tomato cultivars (Zzx171, Zzx162 and Zzx65). All three cultivars showed a reduced colour difference (ΔE) after US-FD. The US-FD method retained higher levels of total carotenoids, lutein, β-carotene, lycopene and antioxidant activity in all cultivars than other methods. While US-HA drying retained the highest level of total phenolic content, chlorogenic acid, 4 -O- caffeoylquinic acid, rutin, protocatechuic acid and ABTS•+ scavenging activity in powders of all cultivars. 'Zzx162' is best suited for US-FD to produce tomato carotenoids-rich functional powder. Powders of 'Zzx162' showed the highest lycopene (14.40 mg/g), β-carotene (6.13 mg/g), and ABTS•+ scavenging activity (8.37 SC 50 mg/mL). While 'Zzx162' with US-HA produced powders rich in chlorogenic acid (58.48 mg/100 g) and rutin (50.33 mg/100 g). These findings suggest that ultrasound pre-treatment is the preferred technology for developing functional tomato powder. Graphical abstract for Impact of different pre-treatments and drying methods on the physicochemical properties, bioactive compounds and antioxidant activity of different tomato (Solanum lycopersicum) cultivars. [Display omitted] • Applied pretreatments and drying methods are important for the bioavilability of the bioactive compounds. • Different pretreatment methods and drying methods affected bioactive compounds differently. • Different pretreatment methods and drying methods affected the colour properties of the tomato fruit functional powder. [ABSTRACT FROM AUTHOR]

Highlights • Temperature controlled plastic tunnels improved the content of carotenoids in most sweet peppers. • White shade nets influenced the accumulation of phenolic acids in sweet pepper cultivars. • Both environments did not affect the marketable yield in sweet pepper cultivars. • Ascorbic acid and vitamin C were higher under the temperature controlled plastic tunnels. • Bound (B) and Free (F)-quercetin-3-glycoside and were higher under the white shade nets. Abstract Antioxidant constituents such as carotenoids (capsanthin, phytoene, lutein, β-cryptoxanthin), polyphenols content (p -coumaric, ferulic, p -hydroxybenzoic, caffeic acid, sinapic acid, and quercetin-3-glucoside) and marketable yield were investigated in 11 sweet pepper cultivars grown under controlled temperature plastic tunnel and white shade net. Marketable yield was not affected by either of the environments, while the interaction between cultivar and growing environment significantly affected the accumulation of antioxidant constituents. The principal component analysis illustrated that controlled temperature plastic tunnel improved the accumulation of carotenoid components and ascorbic acid and vitamin C content in most cultivars. On the contrary, white shade nets favoured the accumulation of phenolic compounds and ORAC activity in most cultivars. A strong correlation was noted between phytoene and carotenoid components in this study (capsanthin r = 0.60; P < 0.001; lutein r = 0.75; P < 0.001; β-carotene r = 0.78; P < 0.001) while ORAC correlated with phenolic compounds. Based on this study, it is possible to refine the choice of environment and cultivar to enhance individual antioxidant constituent groups to improve health benefits for consumers. [ABSTRACT FROM AUTHOR]