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Without a doubt, fruits and vegetables are important components of a balanced and healthy diet. However, their consumption is very low in the world, with the lowest figures being reported in sub-Saharan Africa. The low consumption of fruits and vegetables means unbalanced and unhealthy diets, which has been linked to various diseases and conditions associated with increased mortality rates in worst cases. Poverty is the major contributor to the low consumption of fruits and vegetables in the majority of cases. However, the world, including sub-Saharan Africa, is endowed with numerous wild fruit and vegetable species which can be exploited and incorporated into the diets and help solve some nutrition related concerns. Therefore, in this review, we explore literature on wild fruits and vegetables with a special emphasis on some of the poorest regions of the world and where the lowest consumption figures are reported; their nutritional compositions; the status of their consumption and their role in the diet with a view to uncover their possible role in delivering a healthy and balanced diet as well as helping lower food and nutrition insecurity. A total of 396 articles were downloaded and analysed but only 213 were considered for this review. The results of the search indicate that wild fruits and vegetables are nutritionally rich and high in phytochemicals, especially antioxidants and therefore can possibly play a significant and positive role in delivering a healthy and balanced diet. However, the major challenge is the acceptability, accessibility as well as a lack of interest in wild fruits and vegetables and sheer neglect. People need to be educated using various forms of media on the nutritional and health benefits of these wild food plants with a view to bring them from the forest to the plate. Researchers need to channel more efforts towards domesticating them for ease of access, among other reasons. Governments need to incentivise the subsistence or commercial production of wild fruits and vegetables in order to encourage farmers to cultivate them. However, seeds and/or seedlings need to be made available and affordable to the farmers. The ‘hidden treasures’ in the forests in the form of edible plants could easily play a positive and huge role in delivering a balanced and healthy diet, especially in poor parts of the world. [ABSTRACT FROM AUTHOR]

Thyme oil (TO) fumigation (96 μl l −1 ) to cv. Hass and Ryan avocados significantly reduced anthracnose incidence compared to prochloraz and the untreated control. Also, enhanced activities of β-1,3-glucanase, chitinase were noted in both cultivars. TO fumigation induced the expression of both β-1,3-glucanase and chitinase genes in naturally infected fruit of both cultivars, during storage at 7 or 7.5 °C for up to 21 d and during subsequent simulated market shelf conditions at 20 °C for 5 d. However, the impact of TO fumigation on the β-1,3-glucanase gene expression was higher in both cultivars. Higher gene regulation and β-1,3-glucanase, chitinase activities were observed in cv. Ryan compared to Hass. Although TO fumigation significantly reduced anthracnose incidence in both naturally infected cultivars, the inhibitory effect was slightly higher in cv. Ryan than Hass. Thus, postharvest TO fumigation had positive effects on enhancing anthracnose disease resistance during storage and also gave a residual effect during the simulated shelf life. [ABSTRACT FROM AUTHOR]

Brown rot ( Monilinia spp.) affects the shelf life, fruit quality and marketability of peaches ( Prunus persica L.). Increasing consumer concern regarding food safety makes it necessary to search for natural environmentally friendly alternative products for postharvest disease control. In this investigation, polyethylene terephthalate (PET) punnets containing thyme oil (TO sachets) and sealed with chitosan/boehmite nanocomposite lidding films significantly reduced the incidence and severity of brown rot caused by Monilinia laxa in artificially inoculated peach fruits (cv. Kakawa) held at 25 °C for 5 days. Furthermore, PET punnets containing TO sachets and sealed with chitosan/boehmite nanocomposite lidding films significantly reduced the brown rot incidence to 10% in naturally infected fruits stored at 0.5 °C, 90% RH for 7 days and at the simulated market shelf conditions for 3 days at 15 °C, 75% RH. The chitosan/boehmite nanocomposite lidding films maintained the active components of thyme oil, thymol (56.43% RA), caryophyllen (9.47% RA) and β -linalool (37.6% RA) within the (head space volatiles) punnet. Panellists preferred fruits packed from commercial punnet containing thyme oil (sachets) and sealed with chitosan/boehmite nanocomposite lidding films due to overall appearance, taste, and natural peach flavour. [ABSTRACT FROM AUTHOR]

Postharvest responses of red (‘HTSP-3’) and yellow (‘Celaya’) sweet pepper fruit yield, quality parameters and bioactive compounds (to three types of photo-selective nets and a standard black net) were investigated in this study. Red and yellow peppers produced under the black net retained higher β-carotene, lower total phenolic contents and showed deep red and orange colour after storage. Both peppers produced under the pearl net retained a higher ascorbic content, antioxidant scavenging activity, fruit firmness and also reduced weight loss after storage. Red and yellow peppers grown under pearl and yellow nets resulted in a higher percentage of marketable fruit, after storage. Red pepper grown under the yellow net showed a higher number of odour active aroma compounds in the fruit, while black nets significantly affected the synthesis of odour active aroma compounds during storage. Sensory analysis indicated a preference for red pepper fruits after storage from plants grown under pearl nets. [ABSTRACT FROM AUTHOR]

Avocado fruit has high economic value; however, major post-harvest losses are encountered throughout the supply chain mostly due to anthracnose disease caused by the fungus Colletotrichum gloeosporioides. Increasing consumer concern regarding food safety and demand for organically produced fruits makes it necessary to search for natural environmentally friendly alternative products and processes for the fruit industry; particularly in disease control. Antifungal effects of Gum Arabic (GA) (10%), Aloe vera (AL) (2%), chitosan (CH) (1%) alone or in combination with thyme oil (1%) were investigated in vitro. CH + thyme oil and AL + thyme oil [1:1 or 3:1 v/v] showed fungicidal effects while AL, CH, GA and GA + thyme oil [3:1 v/v] showed fungistatic effects on mycelial growth of C. gloeosporioides in vitro. CH and AL coatings alone or in combination with thyme oil [3:1 v/v], either as preventative or curative treatments in comparison with commercial treatment (prochloraz, 0.05%) and untreated control were evaluated on incidence and severity (lesion diameter) of anthracnose in vivo. Preventative CH + thyme oil treatments significantly reduced the severity of anthracnose (8.9 mm) compared to thyme oil (12.7 mm), AL + TO (14.4 mm), CH (17.8 mm), AL (20.6 mm), PZ (18.3 mm) and untreated samples (34.8 mm). As curative method, the CH + thyme oil combination also reduced the severity of anthracnose by at least 4 mm compared to the other treatments. The total phenols, polyphenol oxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, chitinase, catalase and superoxide dismutase activities, firmness and flesh colour were also determined. Results showed an increase in peroxidase, phenylalanine ammonia-lyase, β-1,3-glucanase, chitinase, catalase and superoxide dismutase activities and total phenolics with reduced loss of firmness and flesh colour following CH + thyme oil treatments. This investigation recommends CH + thyme oil [3:1 v/v] combination treatment as a suitable alternative to the currently adopted prochloraz applications in controlling anthracnose disease in avocado fruit during storage. [ABSTRACT FROM AUTHOR]

Postharvest diseases are one of the major causes for the postharvest loss of horticultural fresh produce during the supply chain. The incidence of postharvest diseases can affect the quality and restrict the shelf life of the horticultural fresh produce. At present strict regulations are enforced by the fresh produce importing countries regarding the minimum pesticide residue levels in the edible portion of the fresh produce. Some fungal pathogens were reported to develop resistance to synthetic fungicides. Waste disposal of fungicides has an impact on environmental footprint. All theses above-mentioned reasons have necessitated the search for a natural novel fungicide to replace the synthetic fungicide application in the packing line as postharvest treatment. Consumer preference to organic fresh produce is increasingly becoming popular in the developed countries. Therefore, this review summarises the use of essential oils in the control of postharvest diseases of horticultural commodities, their mode of actions, effects on the defence mechanism and quality of fresh fruit. Future research must be focused on conducting large scale trials to prove the feasibility of combination treatments. The cost benefit analysis of the treatments needs to be carried out in order to implement their application and the commercial applications of essential oils and host pathogen infection must be investigated in detail in order to control latent infections during postharvest storage. [ABSTRACT FROM AUTHOR]

Abstract: Due to their flavor and nutritional characteristics, papaya fruit are consumed worldwide. As a tropical commodity, storage has serious limitations that result in their rapid deterioration and high incidence of rots during handling and storage. Postharvest handling of papaya differs according to destination. For export markets, there are well-defined postharvest steps established that include technologies that generally avoid disease incidence. For national markets, the postharvest chain is short but characterized by poor handling practices that can result in serious losses due to microorganisms. Anthracnose is considered the main postharvest disease, but development of other rots may also limit good fruit quality, as is the case with, among others, stem-end rots. Control of papaya rots for export markets are applied in accordance with import–export regulations, while for the national market it has typically relied on synthetic fungicides; however, due to their already known ‘side-effects’ on humans and the environment, other alternatives alone or combined should be tested in integrated technologies. We reviewed the available literature on different control methods to reduce postharvest diseases during papaya storage, including those that reported on their effects on fruit quality. Wax combined with fungicides and heat is currently in use. Other methods, such as the application of irradiation, antagonistic microorganisms and natural compounds [e.g. chitosan and plant derivatives (extracts, essential oils and isothiocynates)], are still under evaluation, but have yielded promising initial results. The application of various organic salts and minerals and modified and controlled atmosphere technologies using ozone and volatiles such as 1-methycyclopropane are also under experimentation. We believe that research areas that include preharvest experimentation aimed at reducing postharvest diseases on papaya fruit should be taken into account. Finally, the integration of more than one control method will reduce the incidence of rots, and therefore improve and extend the storage life of this important commodity. [Copyright &y& Elsevier]

Abstract: Mangoes are tropical/sub tropical fruit with a highly significant economic importance. Preferable quality attributes include freedom from external damages such as bruises, latex or sap injury and decay, uniform weight, colour, aroma, firmness (with little give away, not soft), shape and size. The fruit is rich in antioxidants and recommended to be included in the daily diet due to its health benefits such as reduced risk of cardiac disease, anti cancer, and anti viral activities. Maintenance of mango fruit quality during the supply chain depends on many aspects including adequate orchard management practices, harvesting practices, packing operation, postharvest treatments, temperature management, transportation and storage conditions, and ripening at destination. Postharvest losses are high during the supply chain due to harvesting fruit at improper maturity, mechanical damage during the whole chain, sap burn, spongy tissue, lenticels discolouration, fruit softening, decay, chilling injury, and disease and pest damage. The aim of postharvest treatments and management practices in the supply chain is to create suitable conditions or environments to extend the storage life and retain the quality attributes, nutritional and functional compositions. This review summarises the available research findings to retain the overall mango fruit quality and to reduce postharvest losses during supply chain by adopting suitable postharvest novel technologies. [Copyright &y& Elsevier]

Abstract: Efficacy of biocontrol agent Bacillus amyloliquefaciens PPCB004 was evaluated on the control of anthracnose and phomopsis rot in ‘Solo’ papaya pre-treated with 1-methyl cyclopropene (100 μl) (1-MCP) during storage. This treatment was compared to the untreated control, commercial treatment (washing in chlorinated water), stand alone 1-MCP and PPCB004 treatment. Although fruit pre-treated with 1-MCP delayed the ripening (100% yellow) after cold storage by 9–10 d, it showed higher incidence and severity of anthracnose and phomopsis rot than the fruit subjected to commercial treatment. Application of PPCB004 after 1-MCP pre-treatment (1-MCP + PPCB004) reduced the anthracnose and phomopsis incidence and severity after cold storage (10 °C, 85% RH for 14 d) and ripening at 25 °C. The 1-MCP + PPCB004 treatment helped to retain the fruit firmness, overall quality and uniform yellow skin (100%) and flesh colour after ripening. The PPCB004 was effectively recovered from stand alone PPCB004 and 1-MCP + PPCB004 treated fruit after cold storage and ripening. The PPCB004 population showed an increase by 1 log units after ripening in 1-MCP + PPCB004 treated fruit. After ripening the recovery of PPCB004 population was higher (0.7 log units) in 1-MCP + PPCB004. The total recovery of fungal population on the fruit surface after ripening was lower in 1-MCP + PPCB004 and stand alone PPCB004 treated fruit. It can be concluded that application of B. amyloliquefaciens PPCB004 with 1-MCP pre-treated papaya (at 25–30% skin yellow stage) can significantly reduce disease incidence associated with 1-MCP treatment. This treatment has the potential for commercial application in the ‘organic’ papaya industry. [ABSTRACT FROM AUTHOR]

Abstract: Changes in aroma volatiles and sensory attributes with respect to litchi (Litchi chinensis Sonn.) fruit subjected to SO2 fumigation, dilute HCl (pH 0.9–1) dip after SO2 fumigation, modified atmosphere packaging (MAP) (17% O2 +6% CO2) and controlled atmosphere (CA) conditions (CA-1, 3% O2 +7% CO2) at 2°C, 90% RH for 21d were investigated. Citronellol and geraniol are responsible for the fruity, floral, rose and citrus aroma in ‘Mauritius’ litchi fruit. Different postharvest treatments affected the retention of citronellol and geraniol content during storage as follows: MAP (17% O2 +6% CO2)>CA (3% O2 +7% CO2)>SO2 >SO2–HCl dip. A trained panel described woody (alloaromadendrene), spicy (ar-curcumene) and ‘wine’ (ethanol) notes most strongly in SO2-fumigated or SO2 +HCl dipped fruit. The untrained panel preferred the fruit in MAP and disliked commercially SO2-fumigated or SO2 +HCl dipped fruit. The MAP packed fruit showed absence of decay and reduced pericarp browning with acceptable marketability. [Copyright &y& Elsevier]

Abstract: Bacillus amyloliquefaciens PPCB004 was selected as a potential antagonist to control Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer on peach fruit. The HPLC data of PPCB004 indicated the lipopeptides iturin A, fengycin and surfactin as secondary metabolites. The GC/MS analysis of PPCB004 showed 3-hydroxy-2-butanone as the dominant compound (97.52% of relative peak area). Thyme (TO) and lemongrass (LO) oils showed over 50% and 25% inhibition of radial mycelial growth respectively with 8μl oil per plate for all pathogens. Combination treatment with both oils failed to increase the percentage inhibition of radial mycelial growth of the pathogens. Combined application of PPCB004 with TO or LO was tested to assess the effectiveness in the control of these pathogens during postharvest storage. The biofilm formation of PPCB004 was significantly higher in LO than TO. LO (6μlplate−1) and PPCB004 completely inhibited the mycelial growth of the pathogens. Fruit inoculation trials with PPCB004+LO in NatureFlex™ modified atmosphere packaging (MAP), showed lower disease incidence and severity at 25°C for 5d than treatments with PPCB004+MAP, PPCB004+TO+MAP, LO+MAP, TO+MAP or stand-alone MAP. On naturally infected fruit, PPCB004+LO+MAP and LO+MAP treatments retained the total soluble solids/titratable acidity ratio and flesh firmness but failed to stimulate the levels of total phenolic content, phenylalanine ammonia-lyase, β-1,3-glucanase and chitinase activities. Combination of PPCB004 (spray treatment)+LO (in pad delivery system) in NatureFlex™ MAP showed absence of disease and off-flavour development, retained the overall appearance and increased the overall acceptance at market shelf conditions (20°C for 2d) after cold storage at 4°C for 14d. [Copyright &y& Elsevier]

Abstract: The effects of modified atmosphere packaging (MAP) [bioriented polypropylene (BOPP-1 or BOPP-2)] in combination with antimicrobial agents Bacillus subtilis, 107 colony-forming units (cfu)ml−1; ethylenediamine tetraacetic acid, calcium disodium salt hydrate (EDTA) (0.1%); or 4-hexylresorcinol (4-HR) (0.15%) on postharvest decay control and quality retention of litchi cv. McLean''s Red were assessed as possible replacements for commercial SO2 fumigation. Fruits dipped in B. subtilis, EDTA or 4-HR (5min) separately, blow dried (25°C, 3min), packed in BOPP-1, held for 18d at 2°C, 95% RH, and 2d at 14°C, 75% RH were significantly less decayed. The antagonist–BOPP-1 combination also promoted the best bacterial survival during storage. B. subtilis was observed to survive effectively in BOPP-1 (16% O2, 6% CO2; ∼90% RH), but its survival was adversely affected in BOPP-2 (5% O2, 8% CO2; ∼93% RH). Alternaria alternata and Cladosporium spp. were the major decay-causing fungi in BOPP-1 treatments, and Candida, Cryptococcus and Zygosaccharomyces were the predominant yeasts in BOPP-2 treatments. Combination treatments EDTA, 4-HR or B. subtilis in BOPP-1 inhibited polyphenol oxidase (PPO) and significantly reduced pericarp browning and severity. Although the combination treatments EDTA, 4-HR or B. subtilis in BOPP were equally effective in controlling decay and browning, the EDTA and 4-HR affected the natural pinkish-red colour of the pericarp by showing higher h° values (orange–pink). Among the combination treatments, B. subtilis+BOPP-1 had the best potential to control decay, retain the colour and the overall litchi fruit quality during a marketing chain of 20d. [Copyright &y& Elsevier]

The phenolic content and antioxidant properties of fruits would be underestimated if the extraction method is not optimised and bound phenolic content are not considered. A Central Composite Design and Response Surface Methodology were used to optimize sonication time and ethanol concentration to obtain a food-grade phenolic extract from Natal plum fruit (Carissa Macrocarpa). The free and bound phenolics of Natal plum fruit were extracted, and their release was simulated by in vitro digestion. Optimal conditions (38% ethanol and 16.7 min of ultrasonication) yielded 863.99 mg kg-1 fresh weight of total phenolics and 421.52 mg kg-1 fresh weight of total anthocyanins. There were strong correlations between ferric reducing capacity to cyanidin 3-sambubioside (Cy-3-Sa) (R2 = 0.948), and cyanidin 3-O-glucoside (Cy-3-G) (R2 = 0.901). Compared to alkaline hydrolysis, acid hydrolysis produced more bound phenolic compounds. The optimum extract still had low anthocyanin bioaccessibility. The optimal extract of the Natal plum fruit may serve as a functional ingredient due to its high antioxidant capacity. • The Natal plum fruit (NP) (Carissa Macrocarpa) is native to Southern Africa. • Ultrasonication with 38% ethanol for 16.7 min yielded higher total phenols. • The acid hydrolysis of NP released more bound phenolic compounds. • Anthocyanins are mostly degraded by protocatechuic acid in the intestine. [ABSTRACT FROM AUTHOR]

The OPLS-DA, the UPLC–QTOF/MS and chemometric approaches were adopted to discriminate the different varieties belonging to three pumpkin species. Furthermore, this study included a comparison of the phenolic metabolites, antioxidant (DPPH, FRAP and ABTS activity), in vitro α-glucosidase and α-amylase activities, and cell cytotoxicity of the leaves of three varieties of pumpkin species (Cucurbita moschata, C. maxima, and C. pepo). Leaves of all three varieties of pumpkin species contained 23 phenolic metabolites. The OPLS-DA, the UPLC–QTOF/MS and chemometric approach showed that genistin was the candidate biomarker responsible for the separation of butternut squash (C. maxima) from the other two species, while 7-methylquercetin-3-galactoside-6″-rhamnoside-3‴-rhamnoside separated the Caserta squash (C. pepo) from the other two pumpkin species. Leaves of Green Hubbard (C. maxima) showed the highest antioxidant capacity (FRAP and ABTS activities), while butternut squash (C. moschata) showed the highest DPPH scavenging activity. Leaf extracts of butternut squash (C. moschata) and Green Hubbard (C. maxima) showed higher inhibition of α-glucosidase activity (IC 50 18.22 μg mL−1) and α-amylase (IC 50 18.11 μg mL−1) activities respectively, with no cytotoxic effect detected. The phenolic metabolites identified herein for the leaves of each variety of pumpkin species can be potential control markers for further standardisation. Leaves of Green Hubbard (C. maxima) provides functional properties for health benefits. • Genistin detected in the leaves separated the C. maxima from the other two pumpkin species. • 7-methylquercetin-3-galactoside-6″-rhamnoside-3‴-rhamnoside separated the C. pepo from the other pumpkin species. • Leaves of Green Hubbard (C. maxima) showed the highest antioxidant capacities. • Green Hubbard (C. maxima) showed higher inhibition of α-glucosidase and α-amylase activities. • No cytotoxic effect detected in the leaves of all three pumpkin varieties. [ABSTRACT FROM AUTHOR]

Natal plum is a South African indigenous fruit. Natal plum were stored at 2, 4, 10 and 25 °C (control) temperatures up to 12 days, and fruit were evaluated at 4 day intervals for changes in quality and phenolic compounds. The results showed that 2 °C significantly reduced the weight loss and total colour difference while maintaining the quality attributes. Supervised Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) and the ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometer and chemometric approach separated the fruit stored at low temperature from those stored at 25 °C, and a unique marker compound quinic acid was identified with the low temperature fruit. Similarly, cyanidin (aglycone) separated the fruit stored at 2 °C from those stored at other lower temperatures (4, and 10 °C). Thus, it can be proposed that the temperature stress at 2 °C had favoured the cold-induced accumulation of cyanidin derivatives (anthocyanins) to provide chilling tolerance. The bioactive compounds (cyanidin-3- O -pyranoside (10.4 mg kg−1), cyanidin-3- O -glucoside (54 mg kg−1), and quercetin 3- O -rhamnosyl glucoside (57 mg kg−1)] and the antioxidant activity (FRAP assay) were significantly higher in fruit stored at 2 °C for 12 days. Thus, storage of Natal plum at 2 °C for 12 days can be recommended if the fruit are used as a functional ingredient. [ABSTRACT FROM AUTHOR]

Development of anthracnose disease caused by Colletotrichum gloeosporioides Penz. is one of the major issues within the avocado supply chain. Exposure to methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours at 10 and 100 µmol l −1 was investigated as an alternative solution to commercial fungicide – prochloraz® that is currently being used by the industry. The incidence of anthracnose disease was found to be significantly reduced in ‘Hass’ avocado fruit treated with MeJA or MeSA vapours, especially at 100 μmol l −1 . The mechanism involved enhanced activity of defence related enzymes, i.e. chitinase, β -1,3-glucanase and PAL, and higher content of epicatechin. [ABSTRACT FROM AUTHOR]

Kakadu plum (Terminalia ferdinandiana) (KP) is an indigenous fruit used as a functional ingredient in powdered form. Three KP doses (1, 2.5 and 5 g) were digested in a dynamic in vitro gut digestion model over 48 h. Faecal water digests from the colonic reactors were assessed for total soluble polyphenols (TSP), ferric reducing antioxidant power (FRAP), phenolic metabolites and short-chain fatty acids (SCFAs). Effects of digests on cell viability were tested against Caco-2 intestinal and HepG2 hepatic cells. All doses of KP fermentation produced castalagin, corilagin, chebulagic acid, chebulinic acid, and gallic acid. TSP and FRAP significantly increased in 5 g KP digests at 0 and 48 h of fermentation. SCFA concentrations significantly increased after 48 h. Cytotoxic effects of 2.5 and 5 g KP digests diminished significantly after 12 h. Overall, colonic fermentation increased antioxidant activity and polyphenolic metabolites of 5 g KP powder for 48 h. [Display omitted] • Colon microbiomes transform compounds, offering multiple health benefits. • After 12 h, KP digests of 2.5 and 5 g were significantly less cytotoxic. • KP polyphenols was degraded and utilized by colon microbiome. • A 48-h fermentation of KP (5 g) produced highest TSP and antioxidant power. • Highest pyrogallol concentration was found in 5 g KP. [ABSTRACT FROM AUTHOR]

• Natal plum maturity stage M5 (dark-red) is rich in ascorbic acid. • M5 had the highest cyanidin content (Cy3G), (Cy-3-Sa) and cyanidin-3-O-glucoside. • M5 had the highest naringenin 4′-O-glucoside and eriodictyol -7-O-glucoside levels. • M1 stage is rich in phenolic acids and flavonoids. • Antioxidant property was higher in the following order: M5 > M4 > M3 > M2 > M1 stages. • Harvesting at M4 or M5 stages are recommended to provide the functional compounds. This study aims to link morphological and physico-chemical parameters with maturity stages of Natal plum (Carissa macrocarpa), an edible southern African fruit. Harvesting via an integrative holistic approach is recommended for optimal quality and functional compounds. Fruits at dark green (M1), light green (M2), colour break or pink (M3), red (M4), dark red (M5) stages were harvested in 2016 and 2017 seasons. The principal component analysis illustrated the colour value a* (redness), fruit weight, size (length and width), sugars (glucose and fructose), ascorbic acid content, cyanidin derivatives (cyanidin-3-O-pyranoside, cyanidin 3-O-β-sambubioside, cyanidin-3-O-glucoside), naringenin 4′-O-glucoside, and antioxidant property (FRAP) were higher in the following order of maturity stages M5 > M4 > M3 > M2 > M1. Quercetin 3-O-rhamnosyl galactoside and glucoside were higher in green (h° higher) firm M1 to M3 stages. A strong correlation exists between fruit weight, size, a* value and cyanidin derivatives or naringenin 4′-O-glucoside or ascorbic acid content or antioxidant activity. Thus, the M4 and M5 stages of Natal plum can serve as functional food. [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]

Current study was initiated to identify the phytochemicals and the nutritional profile of eleven Kei-apple fruit accessions. Accession FH29 showed the highest level (492.45 mg 100 g −1 fresh weight) of total phenolic content, higher than the referral fruit, blueberry. Pyrogallol was identified as the predominant phenolic compound in all accessions. Accession FH 29 showed the highest (49.75 µmol TEAC g −1 fresh weight) antioxidant capacity. Catechin content was higher in accessions; FH151, FH15, FH14, FH29, FH243, FH 239 and FH 231. Accessions, FH14 and FH232 exhibited higher levels of β-carotene than the referral fruit apples (cv. Top red) and peaches (cv. Excellence). The total sugar (glucose and fructose) was highest (50 mg g −1 fresh weight) in accession FH240. Asparagine (3122.18 mg L −1 ) and gamma-aminobutyric (1688.87 mg L −1 ) were higher in accessions FH239 and FH243 respectively. Overall, the accession Kei-apple FH236 can be regarded as a good source of essential amino acids. [ABSTRACT FROM AUTHOR]

• Grafted fruits showed higher TSS/TA ratio, and ABTS scavenging activity. • Root stock 'Carnivor' improved ascorbic acid content in grafted cantaloup and honeydew melons. • Root stock 'Carnivor' improved β-carotene content in grafted cantaloup melons. • Hexyl acetate discriminated the grafted cantaloups from ungrafted fruits. • Hexadecane discriminated the grafted honeydew melons from ungrafted fruits. Two rootstock crosses of sweet melon and watermelon (Cucurbita moschata × Cucurbita maxima hybrids), 'Kickstart' and 'Carnivor', grafted onto four melon cultivars (cantaloups; 'Majestic', 'Hunter', 'Honeygoal' and 'Honeyval') were evaluated for quality, phytonutrient composition and volatile compounds in the 2020 and 2021 growing season at two harvests. Grafted fruits showed higher SSC/TA ratio, and antioxidant scavenging activity. Grafted 'Majestic/Carnivor' and 'Honeyval/ Carnivor' melons significantly increased the ascorbic acid content than the controls. 'Majestic/Carnivor' melons showed the highest β- carotene and lutein than the controls. PLS-DA score plots discriminated the grafted cantaloupes and honeydew melons from controls based on the concentration of volatile compounds. Hexyl acetate and hexadecane respectively discriminated the grafted cantaloups and honeydew melons from ungrafted fruits. 'Carnivor' rootstocks showed higher expression of volatiles in the grafted cantaloupes and honeydew melons in the heat map. Panellists preferred Majestic/Carnivor' and 'Honeyval/ Carnivor' melons. [ABSTRACT FROM AUTHOR]

[Display omitted] • A metabolomic and chemometric analysis indicated fruit clustering based on 21 metabolites. • Delphinidin 3-galactoside levels were highest in Transvaal milkplum. • Quercetin 3-galactoside was highest in Water berries. • Sand apricot vine and Sour plum inhibited the carbohydrate hydrolyzing enzymes. • Xanthohumol and 3-O-p-coumaroylquinic acid have been identified as bioactive compounds. Using UPLC-QTOF/MS, metabolites were identified in 10 indigenous fruits from South Africa. Metabolomic-chemometric analysis showed chlorogenic acid scored highest for the discrimination of three different fruit clusters. Heat maps showed patterns and groupings based on the metabolite concentrations. The highest concentrations of quercetin 3-O-α- l -arabinopyranoside (401.09 mg/kg), delphinidin 3-galactoside (57.80 mg/kg), procyanidin B-type dimer (527.07 mg/kg) and epicatechin (1349.46 mg/kg), was in Englerophytum magalismontanum (Transvaal milkplum). Syzygium cordatum (Water berry) had the highest concentrations of quercetin 3-galactoside and methyl gallate 3-O-beta- d -glucopyranoside, Ficus capensis (Cape fig) the most 3-CQA and 5-CQA, and Parinari curatellifolia (Mobola plum) had the highest FRAP (9.5 mmol TEAC/g) and DPPH (14.2 IC 50 µg/mL) scavenging activities. When compared to eight other indigenous fruits, Ximenia caffra (Sour plum), and Landolphia kirkii (Sand apricot vine), showed the highest inhibition of carbohydrate hydrolysing enzymes. Correlation analysis identified candidates responsible for each biological activity in these fruits, proving their utility as functional ingredients. [ABSTRACT FROM AUTHOR]

• Steam blanching (in 5% lemon juice) retained the colour and quality of Solanum retroflexum Dun. • Hot water/steam blanching reduced the tannin, oxalate and phytate contents. • Hot water/ steam blanching increased the peak responses for steroidal saponins. • Three biomarkers were identified for the separation of the steam blanching. • Steam blanching preserved the functional compounds in Nightshade leaves. Not much information is available on the changes of phenolic metabolites or anti-nutritive compounds in African nightshade leaves during moist cooking. Blanching methods (boiling, microwave, and steaming) using 5–20% lemon juice was compared with the plain water as a control. Lemon juice at 20% significantly increased the total colour differences (ΔE). Chlorophyll content and the overall acceptance were highest for samples steamed in 5% lemon juice. Steam blanching in plain water reduced the tannin, oxalate and phytate contents but showed higher comparative peak responses for steroidal saponins. Neochlorogenic, chlorogenic, and caffeoylmalic acid, kaempferol O-rhamnosyl hexoside, and rutin were identified blanched leaves. Principle component analysis (PCA) discriminated between blanching treatments while Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) showed clear group distinctions between the blanching treatments. Chlorogenic acid, neochlorogenic acid and cryptochlorogenic acid were the responsible biomarkers for the separation of the steam blanching treatments. Thus, steam blanching preserves the functional compounds in nightshade leaves. [ABSTRACT FROM AUTHOR]