White Fruit Research Articles

Tolerance of tomato to cadmium-induced stress: analyzing cultivars with different fruit colors.

The objective of the present study was to assess the response of tomato cultivars with different fruit colors to exposure to increasing Cd levels in the substrate by measuring the impacts of Cd on the oxidative stress indicators and physicochemical features of fruits, as well as plant development and yield components. A completely randomized experiment in a 3 × 3 factorial design [tomato cultivar (which produces purple, red, or white fruits) vs Cd level in the substrate (0, 3.6, or 12 mg kg-1)] was performed. The cultivation of plants in substrate containing 3.6 mg kg-1 Cd did not affect yield, but fruits exhibited nonpermissive Cd concentrations in both peel and mesocarp across all cultivars. By contrast, yield was decreased in plants with red and white fruits after their cultivation in substrate containing 12 mg kg-1 Cd, while the productivity of plants with purple fruits was maintained under such conditions. The hydrogen peroxide content in the fruit mesocarp depended only on cultivar. However, an increased lipid peroxidation level was detected in the mesocarp of purple fruits at the highest Cd concentration. No parameters of fruit quality [i.e., diameter, length, °Brix, pH, titratable acidity, color (L*, a*, and b*), and concentrations of lycopene and β-carotene in mesocarp] were affected by long-term exposure to Cd at 12 mg kg-1. In conclusion, the results of this study suggested that the potential Cd side effects on diverse tomato quality features can be buffered at the fruit level because these features were maintained at the usual values despite high Cd concentrations in tomato peel and pulp. Moreover, these buffering mechanisms are independent of lycopene and β-carotene concentrations in fruit peel, since the three tomato cultivars that were evaluated in the present study (white fruits, possessing no or negligible concentrations of these carotenoids, and red and purple tomato, possessing high lycopene and β-carotene concentrations) were able to sustain several fruit quality parameters after long-term exposure to high Cd concentrations in the substrate.

Sorbus doshonglaensis (Rosaceae), a new species from southeastern Xizang, China

Sorbus doshonglaensis (Rosaceae), a new species from southeastern Xizang (Tibet) in China, is described and illustrated. The new species is morphologically similar to S. kiukiangensis, but differs in having (4–)5–7 pairs of leaflets, ovate to semi-orbicular stipule, and yellowish white fruits.

Application of backpropagation method for quality sorting classification system on white dragon fruit (Hylocereus undatus)

Several problems related to determining the quality of dragon fruit quality are: fruit disease, harvest time selection, sorting process and post-harvest grading. Determination sorting dragon fruit quality by observing the appearance of fruit, fruit smoothness, presence or absence of defects and fruit size. However, this quality determination has disadvantages such as longer sorting time and different perceptions of farmers about the quality of dragon fruit. To solve this problem, we need a sorting system that is able to determine the quality of dragon fruit effectively and efficiently without damaging the dragon fruit. In this study, determining the quality of white dragon fruit using digital image processing techniques and intelligent systems. The output of the digital image processing technique is five morphological features such as area, perimeter, length, diameter and metric. This feature is the input of the backpropagation method so that the quality of white dragon fruit is divided into 3 classes such as class A, class B and class C. The results showed the best network architecture model was 5,8,5,3 with the best testing accuracy rate of 86.67%.

Methods of drying on fruit quality of Byadagi chilli

The experiment was conducted to study the effect of different drying methods in red chilli (Byadagi dabbi) at Horticultural Research and Extension Station, Devihosur, Haveri, Karnataka, during 2016 and 2017 in rabi season. Drying in solar tunnel dryer method is found to be the best option in field situation for reducing the average drying period (6.0 days) and significantly least per cent of white fruits (7.5 %), as compare to other treatments. This was mainly due to increased average maximum temperature (54.2 0C), minimum temperature (29.2 0C) and reduced relative humidity (57 %) compared to outside temperature (Tmax - 36 0 C & Tmin-18 0C and RH – 74%). This resulted in rapid loss of moisture from the fruits and ultimately reduced the drying period and fruit whitening. The fruit quality parameters were not significantly affected by the methods of drying in chilli.

Antioxidant and Anti-Inflammatory Effects of White Mulberry (Morus alba L.) Fruits on Lipopolysaccharide-Stimulated RAW 264.7 Macrophages.

In this study, the protective effects of white mulberry (Morus alba) fruits on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages were investigated. The ethanol (EtOH) extract of white mulberry fruits and its derived fractions contained adequate total phenolic and flavonoid contents, with good in vitro antioxidant radical scavenging activity. The extract and fractions also markedly inhibited ROS generation and antioxidant activity. After treatment with the EtOH extract and its fractions, LPS stimulation-induced elevated nitric oxide (NO) production was restored, which was primarily mediated by downregulation of inducible NO synthase expression. A total of 20 chemical constituents including flavonoids, steroids, and phenolics were identified in the fractions using ultra-high-performance liquid chromatography (UHPLC)-quadrupole time-of-flight (QTOF) high-resolution mass spectrometry (HRMS). These findings provide experimental evidence of the protective effects of white mulberry fruit extract against oxidative stress and inflammatory responses, suggesting their nutraceutical and pharmaceutical potential as natural antioxidant and anti-inflammatory agents.

Identification of candidate genes influencing anthocyanin biosynthesis during the development and ripening of red and white strawberry fruits via comparative transcriptome analysis.

Strawberries are one of the most economically important berry fruits worldwide and exhibit colours ranging from white to dark red, providing a rich genetic resource for strawberry quality improvement. In the present study, we conducted transcriptome analyses of three strawberry cultivars, namely, ‘Benihoppe’, ‘Xiaobai’, and ‘Snow White’, and compared their gene expression profiles. Among the high-quality sequences, 5,049 and 53,200 differentially expressed genes (DEGs) were obtained when comparing the diploid and octoploid strawberry genomes and analysed to identify anthocyanin-related candidate genes. Sixty-five DEGs in the diploid genome (transcriptome data compared to the diploid strawberry genome) and 317 DEGs in the octoploid genome (transcriptome data compared to the octoploid strawberry genome) were identified among the three cultivars. Among these DEGs, 19 and 70 anthocyanin pathway genes, six and 42 sugar pathway genes, 23 and 101 hormone pathway genes, and 17 and 104 transcription factors in the diploid and octoploid genomes, respectively, correlated positively or negatively with the anthocyanin accumulation observed among the three cultivars. Real-time qPCR analysis of nine candidate genes showed a good correlation with the transcriptome data. For example, the expression of PAL was higher in ‘Benihoppe’ and ‘Xiaobai’ than in ‘Snow White’, consistent with the RNA-seq data. Thus, the RNA-seq data and candidate DEGs identified in the present study provide a sound basis for further studies of strawberry fruit colour formation.

Integrated metabolomics and transcriptomics reveal the differences in fruit quality of the red and white Fragaria pentaphylla morphs

Fragaria pentaphylla is a perennial herb with two morphs that produce either white or red fruit. A combined metabolomic and transcriptomic analysis of the red and white fruits was conducted to reveal the different accumulated metabolites and differentially expressed genes between the red and white fruits. Red fruits of F. pentaphylla had higher quality with abundant flavonoids, free amino acids, and vitamins, compared with white fruits. Four anthocyanins, one procyanidin and 15 flavonoids in red morphs were significantly higher than in white morphs. The low level of pelargonin O-hexosyl-O-hexoside, pelargonidin O-hexoside and petunidin O-rutinoside might contribute to the white color of the F. pentaphylla flesh. Eighteen amino acids, except glycine or glutamine, were found in both the red and white morphs. Red fruits had a higher content of amino acids than white fruits. No DEG was involved in the pathway for amino acids synthesis, indicating that the higher levels of amino acids in red fruits than in white were not due to an increased amino acid biosynthesis. Integrated metabolomic and transcriptomic data suggested that COR, CHI, DFR, PKS and COMT genes might be related to the synthesis of flavonoids. Besides, 7OMT and PKS genes were shown to be closely associated with alkaloid and polyphenol synthesis. These results provide new insights into the molecular mechanisms of the color and nutrients in strawberries.

Process optimization and ethanol use for obtaining white and red dragon fruit powder by foam mat drying.

Dragon fruit shows good sensory and nutritional attributes, but it is also highly perishable. Drying is a unitary operation that promotes the reduction of moisture content, extending the useful life of the product. In this study, the elaboration of white and red dragon fruit powder by foam mat drying was studied with optimization of the proportion of foaming agent and stirring time. The use of ethanol and air temperature were evaluated on drying kinetics, effective moisture diffusivity (Deff ), and drying rate (DR). The study was divided into two steps. In the first, density, stability, porosity and overrun foam were evaluated and the optimal condition was determined. For the white and red pulp foams, the optimal conditions were, respectively, 26.88min and 4.12kg 100 kg-1 and 23.5min and 3.44kg 100 kg-1 . In the second step, the foam was subjected to ethanol pretreatment and convective drying (50 or 70 °C). The best condition involved pretreatment and the highest tested temperature, with the shortest drying time and the highest Deff and DR. PRACTICAL APPLICATION: Foam mat drying is a suitable method for drying perishable fruits, such as dragon fruit. The foam properties need to be optimized to ensure the success of the drying process. The ethanol pretreatment and the drying air temperature influence the drying kinetics. Therefore, determining the optimal process conditions is very important.

Profiling of free amino acids in sparkling wines during over-lees aging and evaluation of sensory properties

Sparkling wines produced with the nontraditional grape varieties Villenave, Niagara, Manzoni and Goethe, and also a classic Chardonnay variety, were investigated in this study. The aim was to determine the influence of the length of time for which the wines were exposed to biological aging in contact with yeast lees (over-lees) on the nitrogen composition and the characteristics of the sensory profile. Significant changes were observed in the concentration of free amino acids in the sparkling wines during over-lees aging. The use of multivariate analysis to investigate the nitrogen composition of sparkling wines proved to be an interesting tool to differentiate sparkling wines according to the time of biological aging. The principal component analysis clearly separated the sparkling wines according to the time of over-lees aging considering the nitrogen composition, and this behavior was observed for all varieties. Sparkling wines with 15 and 18 months of over-lees aging were associated with most of the amino acids analyzed. The sensory profiles obtained for the sparkling wines with 18 months of aging on yeast lees was characterized by descriptors of white and citrus fruits, floral and/or orange blossom, honey, butter, notes of toasted bread and vegetal, and straw-colored.

DNA index and anatomical aspects of the micrografting of dragon fruit on different rootstocks

Abstract The objective of this work was to evaluate the viability of the micrografting of yellow dragon fruit (Selenicereus megalanthus) on different rootstocks, based on DNA content and anatomical analyses. The used rootstocks were: yellow dragon fruit, white dragon fruit (Hylocereus undatus), Saborosa (Selenicereus setaceus) dragon fruit, and the Cebra and Orejona red dragon fruit (Hylocereus polyrhizus) varieties. The experimental design was completely randomized with five treatments and four replicates of five plants. After 30 days of cultivation, the following traits were evaluated: length and diameter of the micrografts and microrootstocks; and root length, percentage of setting, and fresh mass of the micrografts. Flow cytometry analyzes were performed before and after micrografting to verify genetic stability and the occurrence of endoreduplication. In addition, histological sections were made in the micrografting region to verify the connections of vessels and tissues between the graft and the rootstock. Endoreduplication was observed in all treatments. The amount of DNA in the yellow dragon fruit micrograft increased on the red Orejona variety. The presence of vessel connections was verified between the micrografts and microrootstocks. The yellow dragon fruit was also more vigorous when grafted on Orejona. Based on DNA content and anatomical analyses, in vitro yellow dragon fruit micrografting is feasible in all used rootstocks.

Variability in chemical composition of eggplants and sweet peppers

Variability in chemical composition of eggplants and sweet peppers

The reduction of plant sink/source does not systematically improve the metabolic composition of Vitis vinifera white fruit

The quality of wine grapes depends on the balance between primary and secondary metabolites. Unlike many perennial crops that accumulate starch in the fruits before ripening, the non-climacteric grapes ripe with no previous carbon reserves. Based on the assumption that fruit carbon sink is limiting metabolite accumulation in grapes, bunch thinning is performed to limit plant Sink/Source (S/S). We studied the effects of severe bunch thinning on the accumulation of primary metabolites and on four families of glycosylated aroma precursors (GAPs) at the arrest of fruit phloem unloading of two white grape Vitis vinifera cvs. At plant level, crop reduction resulted in significant losses of metabolites to be accumulated in the fruits: i.e. up to 72% for sugars, 75% for organic acids and GAPs. Nevertheless, S/S manipulation could not modify the balance between GAPs and primary metabolites or increase the concentration in GAPs in the physiologically ripe grape.

WHITE MULBERRY (MORUS ALBA L.) FRUIT-ASSOCIATED BACTERIAL AND FUNGAL MICROBIOTA

Morus alba L. has been worldwide cultivated and commercially exploited plant with profound potential in environmental management, food and medicinal industries. Plant-associated microbial communities are playing an essential role in sustainable plant development. In the present study, the bacterial and fungal microorganism populations distributed on the white mulberry fruits harvested in the Czech Republic for the first time were characterized by metagenomics approach. A total of 62 bacterial and 37 fungal families were identified on white mulberry. Bacterial population was represented by the genera Tatumella, Leuconostoc, Frateuria and Pseudomonas, while fungal microorganisms – by Hanseniaspora, Cryptococcus, Cladosporium and Phoma. Both potentially beneficial, inducing resistance in the hosting plant, and pathogenic, responsible for disease development, microorganisms were detected. The information on the prevalence of bacterial and fungal microorganisms on the carposphere of M. alba is highly relevant for the development of strategies for environment-friendly plant cultivation, disease management and prevention.

Methods of drying on fruit quality of Byadagi chilli

The experiment was conducted to study the effect of different drying methods in red chilli (Byadagi dabbi) at Horticultural Research and Extension Station, Devihosur, Haveri, Karnataka, during 2016 and 2017 in rabi season. Drying in solar tunnel dryer method is found to be the best option in field situation for reducing the average drying period (6.0 days) and significantly least per cent of white fruits (7.5 %), as compare to other treatments. This was mainly due to increased average maximum temperature (54.2 0C), minimum temperature (29.2 0C) and reduced relative humidity (57 %) compared to outside temperature (Tmax - 36 0 C & Tmin-18 0C and RH – 74%). This resulted in rapid loss of moisture from the fruits and ultimately reduced the drying period and fruit whitening. The fruit quality parameters were not significantly affected by the methods of drying in chilli.

Optimization of Spray Drying Parameters for White Dragon Fruit (Hylocereus undatus) Juice Powder using Response Surface Methodology (RSM)

This study was conducted to optimize the production of spray-dried white dragon fruit (Hylocereus undatus) powder using resistant maltodextrin as wall material. The inlet air temperature (140 °C, 150 °C and 160 °C), outlet temperature (75 °C, 80 °C and 85 °C) and resistant maltodextrin concentrations (20%, 25% and 30%) were tested as independent variables. Process yield, moisture content, water activity, solubility, hygroscopicity and bulk density of the powders were analysed as responses. Process yield significantly (p<0.05) increased with increasing inlet temperature and decreasing resistant maltodextrin concentration. Outlet temperature and resistant maltodextrin concentration significantly (p<0.05) reduced the moisture content and water activity of the white dragon fruit powder. Powder solubility and hygroscopicity significantly (p<0.05) increased as inlet and outlet temperature increased. Bulk density values decreased as inlet and outlet temperature increased. An optimum conditions for spray dried white dragon fruit powder that would produce high in yield, low moisture content, low water activity, high solubility, low hygroscopicity and high bulk density were found at 153 °C inlet temperature, 82 °C outlet temperature and 20% concentration.

Metabolomic and antioxidant properties of different varieties and origins of Dragon fruit

Dragon fruit has appealed much concern from consumers as a novelty fruit with potent nutritional and medicinal benefits. Dragon fruit quality warrants comprehensive evaluation, based on the contents of pigments and health-promoting natural compounds in different varieties. This study was aimed to evaluate the differences among dragon fruitvarieties extracted with methanol–water (CD3OD-D2O) and methanol (CD3OD) by proton nuclear magnetic resonance (1H NMR)-based metabolomics approach. The variation features of the metabolite profiles were studied between varieties and origins of dragon fruit, considering the differences in principal component analysis (PCA). The hierarchical clustering analysis (HCA) based on score values of PCA model was also performed to analyze the distance between samples based on metabolites contents. The results of 1H NMR spectra showed that the CD3OD-D2O extracts quantitatively differ from CD3OD ones. In dragon fruit extracts, 36 metabolites were identified. The results demonstrated that the methanol and methanol/water extracted similar compounds with higher intensity in methanol. The metabolic differences among varieties were also shown for CD3OD extracts by comparing both Pareto and UV scaling methods. The big size red fleshed dragon fruit (samples 2 and 3), growing in Israel were clustered similar to that growing in Thailand with the abundance of phenolic compounds. Glucose and fructose were more prominent in the yellow and white fleshed fruit (samples 4 and 5) growing in Israel. To support the obtained results two dimensional 1H–1H J-resolved and UHPLC-MS measurements were carried out. This research gain novel insights into the field as the first NMR metabolites fingerprinting of the major dragon fruit varieties. The correlations between DPPH, CUPRAC, antioxidant and metabolomic properties were also evaluated. The chemical markers associated with varieties of dragon fruit quality and their appearances were identified and can be utilized for the basis of authentication purpose of this fruit.

Volatile constituents and ellagic acid formation in strawberry fruits of selected cultivars

Strawberries (Fragaria × ananassa Duch.) are considered a functional food and pleasing fruit in China, mainly because of their high concentration of ellagic acid (EA) and their aroma. A total of 127 volatile compounds were identified by HS–SPME–GC–MS. Changes in volatile constituents and EA were investigated in 50 strawberry cultivars in the red-ripening stage and in 6 cultivars, including ‘Benihoppe’, ‘Snow White’, ‘Yanli’, ‘Kaorino’, ‘Tokun’, and ‘Xiaobai’, at four developmental stages. The results indicated that the components and amounts of volatile compounds and EA markedly varied among and within cultivars. Through multivariate statistical analysis of the volatile compounds, 50 cultivars were divided into 4 clusters. Aromatic components that affected the cluster formation of cultivars were detected. Volatile compounds varied quantitatively among the 6 varieties during the developmental stages, and distinct changes were observed in both red-turning fruits and red-ripening fruits compared with white fruits. Except for ‘Xiaobai’, which showed the highest EA content at the red-ripening stage, the other 5 cultivars exhibited the highest EA level at the large green fruit stage. Partial least squares–discriminant analysis (PLS–DA) of the profiles of volatile compounds indicated that large green fruits were characterized by EA and aldehydes; white fruits were characterized by ketones and alkanes; and red-ripening fruits were characterized by esters, acids, furans, and alcohols. The results contribute new and important information to breeding programs and the desirable cultivation of strawberry production.

Transcriptome profiling provides insights into the fruit color development of wild Lycium ruthenicum Murr. from Qinghai-Tibet Plateau.

Lycium ruthenicum Murr. is an important ecological and economic species in the Qaidam Basin of Qinghai-Tibet Plateau. Its black fruits (BF) are rich in anthocyanins, which have health-promoting properties for humans and thus provide nutritional benefits for this plant. Although the fruit quality of natural white fruit (WF) is affected by the disappearance of pigmentation in phenotypes, this phenomenon provides an opportunity to unravel the complex color metabolic networks. In this study, anthocyanin profiling confirmed that WF was formed due to anthocyanin loss. Transcriptome analysis of BF and WF revealed 101,466 unigenes, 261 of which were identified as the putative homologs of color-related genes in other species. Genes encoding the enzymes involved in flavonoid biosynthesis were also identified systematically. The structural gene expression levels of chalcone synthase (CHS), chalcone isomerase (CHI), flavonoid 3'5'-hydroxylase (F3'5'H), dihydroflavonol 4-reductase (DFR), anthocyanidin synthase (ANS), and anthocyanidin 3-O-glucosyltransferase (UFGT) were highly similar and significantly positively correlated with anthocyanin accumulation rate in BF. In particular, F3'5'H, UFGT, ANS, and DFR expression levels in BF were 2391, 119, 96, and 85 times higher than those in WF at S3 (35days after anthesis), respectively. This result strongly suggests that the low expression of these genes in WF is responsible for the anthocyanin loss. Meanwhile, the expression patterns of the anthocyanin regulatory genes were also investigated by qRT-PCR. Mass sequencing data were obtained and annotated by deep sequencing and provided a platform for future function and molecular biological research on L. ruthenicum Murr.

Transcriptome and Flavonoids Metabolomic Analysis Identifies Regulatory Networks and Hub Genes in Black and White Fruits of Lycium ruthenicum Murray.

Lycium ruthenicum Murry. is a highly nutritional cash crop due to its fruit abundant anthocyanins. To understand the complex metabolic networks underlying the color formation in black and white fruits of L. ruthenicum, we conducted transcriptome and flavonoid metabolic profiling to identify the candidate genes possibly involved in flavonoid biosynthesis. As a result, 147 flavonoids were identified and there was almost no anthocyanin in white fruits, while luteolin, kaempferol, and quercetin derivatives showed markedly higher abundance. Furthermore, applying weighted gene co-expression network analyses, 3 MYB, 2 bHLH, 1WRKY and 1 NAC transcription factor, associated with anthocyanin biosynthesis were identified. A bHLH transcription factor, LrAN1b showed the greatest correlations with anthocyanin accumulation with no expression in white fruits. In addition, gene function analysis and qRT-PCR experiments identified a new activated anthocyanin MYB transcription factor designed as LrAN2-like. Yeast two-hybrid and transient tobacco overexpression experiments showed that LrAN1b could interact with LrAN2-like and LrAN11 to form MBW complex to activate the anthocyanin pathway. The yeast one-hybrid experiment indicated that LrAN2-like bonded anthocyanin structural gene LrDFR and LrANS promoters. Heterologous expression of LrAN1b in tobacco can significantly increase the anthocyanin content of tobacco florals and capsules, and activate anthocyanin synthesis related genes. Taken together, an anthocyanin regulatory network model in L. ruthenicum fruit was proposed firstly and we speculate that the white fruit phenotype was due to abnormal expression of LrAN1b. The findings provide new insight into the underlying mechanism of flavonoids, laying the foundation for future functional and molecular biological research in L. ruthenicum.

A blueberry MIR156a-SPL12 module coordinates the accumulation of chlorophylls and anthocyanins during fruit ripening.

Color change is an important event during fruit maturation in blueberry, usually depending on chlorophyll degradation and anthocyanin accumulation. MicroRNA156 (miR156)-SPL modules are an important group of regulatory hubs involved in the regulation of anthocyanin biosynthesis. However, little is known regarding their roles in blueberry or in chlorophyll metabolism during color change. In this study, a MIR156 gene (VcMIR156a) was experimentally identified in blueberry (Vaccinium corymbosum). Overexpression of VcMIR156a in tomato (Solanum lycopersicum) enhanced anthocyanin biosynthesis and chlorophyll degradation in the stem by altering pigment-associated gene expression. Further investigation indicated that the VcSPL12 transcript could be targeted by miR156, and showed the reverse accumulation patterns during blueberry fruit development and maturation. Noticeably, VcSPL12 was highly expressed at green fruit stages, while VcMIR156a transcripts mainly accumulated at the white fruit stage when expression of VcSPL12 was dramatically decreased, implying that VcMIR156a-VcSPL12 is a key regulatory hub during fruit coloration. Moreover, VcSPL12 decreased the expression of several anthocyanin biosynthetic and regulatory genes, and a yeast two-hybrid assay indicated that VcSPL12 interacted with VcMYBPA1. Intriguingly, expression of VcSPL12 significantly enhanced chlorophyll accumulation and altered the expression of several chlorophyll-associated genes. Additionally, the chloroplast ultrastructure was altered by the expression of VcMIR156a and VcSPL12. These findings provide a novel insight into the functional roles of miR156-SPLs in plants, especially in blueberry fruit coloration.