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Cucumber is one of the most widely consumed vegetables worldwide, and the fruit spine is an important fruit quality trait. Expansins play critical roles in fruit development; however, the regulation of expansins in cucumber fruit spine development has not been reported. In this study, 33 expansin genes were identified in the cucumber genome V3; additionally, expansin genes in Citrullus lanatus, Cucumis melo, Cucurbita maxima, Lagenaria siceraria, and Benincasa hispida were also identified. Phylogenetic analysis of expansin proteins in Cucurbitaceae and Arabidopsis showed that they evolved separately in each plant species. Phylogenetic analysis showed that C. maxima was derived earlier than the other five Cucurbitaceae species. The expression of CsEXPA2, CsEXPA14, and CsEXLA3 varied in cucumber lines with different fruit spine densities. A yeast two-hybrid assay showed that a putative auxin transporter encoded by numerous spine gene (ns) interacts with CsEXLA2, which may be involved in the development of the numerous spines in cucumber. These results provide novel insights into the expansins related to plant development and fruit spine development in cucumber.

Watermelon (Citrullus lanatus) is one of the world's most important fruit crops, and China produces the most watermelons in the world. Recently, a watermelon variome consisting of 414 key resequenced accessions was reported. However, the genetic relationships and pedigree of Chinese watermelon varieties in the seed market remain unclear. In this study, 241 evenly distributed perfect single nucleotide polymorphisms (SNPs) derived from the watermelon variome were selected for variety identification. The diversity of 247 Chinese watermelon varieties was identified based on their SNP genotypes. The 247 watermelon varieties were clustered into five subpopulations: the East Asian ecotype, intermediate ecotype, small fruit with red flesh ecotype, small fruit with yellow flesh ecotype, and American ecotype. We further established the pedigree of four subpopulations, of which JingXinNo.1, ZaoChunHongYu, HuangXiaoYu and XiaoLan, and Sugarlee were the main doner of the East Asian ecotype, small fruit with red flesh ecotype, small fruit with yellow flesh ecotype, and American ecotype, respectively. Thirty-two core SNPs were selected and applied in watermelon variety identification. They were also validated by the Kompetitive allele-specific PCR (KASPar) platform. The present study furthered our understanding of the genetic relationships and pedigree of watermelon varieties in China, and will help to manage the plant variety protection in watermelon.

Citron watermelon (Citrullus lanatus var. citroides) is a multi-purpose cucurbit crop serving the food, feed and the pharmaceutical sectors. The fresh and dried young leaves, fruit and seed are sources of vital human nutrients, and unique phytochemical compounds with pharmacological and therapeutic values. Citron watermelon is indigenous to Africa but commercial products are not widely developed and the crop is largely neglected and underutilized in the region. This is attributed to lack of dedicated research and development efforts and well-defined value chains for citron watermelon genetic resources. The objective of this review was to document the nutritional and phytochemical compositions, pharmacological and therapeutic values of citron watermelon to aid future production, utilization, genetic conservation, research and product development. The review serves as a foundation information on the unique values of citron watermelon to guide future research and development. It recommends collaborative and detailed biochemical analysis efforts for product discovery and optimal use of health-promoting bioactive compounds using the diverse genetic resources available in Africa and elsewhere. This will enhance the commercial value and benefit sharing from citron watermelon in the horticulture, food and pharmaceutical industry.

Bottle gourd (Lagenaria siceraria (Molina) Standl.] and citron watermelon (Citrullus lanatus var. citroides (L.H. Bailey) Mansf. ex Greb.) are amongst the widely grown yet under-researched cucurbits genetic resources in sub-Saharan Africa (SSA). Fresh immature leaves, fruit and seed are used for food and medicinal purposes in the region. Furthermore, both species are used as rootstock and donors of novel genes for commercial production and breeding of sweet dessert watermelon cultivars. Despite their economic value and contribution to food and nutrition security in the region, bottle gourd and citron watermelon genetic resources remain under-utilized and largely un-explored for commercial product development. The objective of this review was to document the unique values of bottle gourd and citron watermelon for genetic improvement and development of value-added food and non-food products, and to highlight regional and global efforts on conservation, production, processing, commercialization and various enterprise development of these important indigenous species. The review discussed on the value of both crops as a rootstock to improve fruit yield and quality of cultivated watermelon. This is followed by important summaries on phenotypic and genetic variation of bottle gourd and citron watermelon genetic resources and implications for new cultivar design. Finally, the review highlighted value-added non-food and food-based products developed based on indigenous knowledge systems in SSA and availability and access to genetic resources of bottle gourd and citron watermelon for breeding, product design and deployment.

Citrullus colocynthis (C. colocynthis) seed is a common and expensive cuisine in West African diet unlike the seeds from Citrullus lanatus (C. lanatus) that are agro waste. The oils from these seeds were comparatively profiled using their physicochemical properties, fatty acids and phenolic contents, in-vitro antioxidant capacity (DPPH, TEAC, FRAP, ORAC), inhibitions of lipid peroxidation and tyrosinase. Toxicities of the oils in mice were also assessed using plasma AST, ALT, cholesterol, HDL-C, liver, heart and kidney (GSH, GPx and SOD) and clastogenic effects in mouse bone marrow. Citrullus lanatus oil contains higher peroxides, saponification, saturated fatty acids and stearic acid (6-fold) levels, with a lower acid value when compared to C. colocynthis. Strong antioxidant capacity, inhibition of lipid peroxidation and tyrosinase by C. lanatus oil extract is proposed to be related to the presence of catechins that are absent in C. colocynthis. The in-vivo study indicated that C. lanatus induced significant increase in ALT while a significant increase of AST was observed in the C. colocynthis treated group. Citrullus lanatus induced a significantly (p 0.05). This work reports for the first time the presence of stearic acid and catechin in C. lanatus oil which is important for its compelling in vitro activity. High doses of both oils could evidently induce toxicological indices in mice.

Background Agro-waste is of rising concern since they present social, economic and environmental challenges. Conversion of food waste is receiving an increasing attention towards the fact that these materials represent possible utilization sources for conversion into useful products and increasing the demand for natural bioactive compounds. Watermelon (Citrullus lanatus) is consumed all over the world that contains a large number of seeds and rind, which is discarded and used as animal feed. These by-products contain phytochemical compounds with great nutritional and functional potential. Scope and approach This review article describes the scientific studies from the last five years regarding the nutritional and bioactive compounds present in the watermelon rind (WMR) and watermelon seeds (WMSs). This review also focused on their nutraceutical worth fully justified by the presence of functional active compounds, as well as their potential industrial application for future research concerning novel or functional, nutraceutical, pharmaceutical and cosmeceutical product development. Key findings and conclusion: WMR is a rich source of fatty acids, minerals, and phenolic compounds and dietary fibers. It also contains soluble carbohydrates (45–65%), carotenoids, alkaloids, saponin, and phytates. WMSs are an excellent source of protein (15–50%) such as albumin, globulin, prolamin, and glutelin. WMSs are also a good source of vitamin B-complex (B1, B2, B3, B6 B12), polyunsaturated fatty acids, essential and non-essential amino acids as well as phenolic compounds. Moreover. Watermelon by-products also present therapeutic properties including anti-diabetic, antioxidant, antihypertensive, anti-inflammatory, antiulcer, antitumor, hypocholesterolemic, hepato-, nephron- and neuro-protective effects and antibacterial properties fully evidenced from recently published literature. Therefore, the use of these byproducts to design and develop innovative functional food products with added value is important for sustainability across the food chain. Nevertheless, further research is needed on the clinical studies of WMR and WMSs to fully support the development of functional food products, nutraceutical and pharmaceutical applications.

The presently employed synthetic cutting fluids in machining applications lead to skin irritations, hazardous aerosols, ingestion etc., to the machine tool operators. Accomplishing sustainable green machining through bio-cutting fluids, is the key motivating factor behind this work, even though the phenomenon of heat generation is inevitable in the machining process. In the present investigation, Citrullus lanatus extract is chosen as a potential candidate for bio-cutting fluid, since it offers multiple benefits such as increased tool life, cleaner production atmosphere, efficacious heat dissipation, healthy operating conditions, etc. Hybrid LM0-6SiCp-4Grp composite is selected for study since; it has potential applications in marine, aerospace, defence and automotive sectors. Experimentation is carried out with Citrullus lanatus extract as bio-cutting fluid in turning of hybrid LM0-6SiCp-4Grp composite under different processing conditions. The presence of green solution based on Citrullus lanatus extract curtails the rise of temperature significantly during turning operation. Higher magnitude of temperature decrease is observed when the percentage of the concentration of Citrullus lanatus extract is increased, irrespective of depth of turning. Bio-nature and cooling qualities of this green-cutting fluid can contribute its share for green machining and sustainable turning environment. The investigations are further progressed using machine learning algorithms based on the different categories of logical regressions implemented through the Python program. Random forest regression shows better results with 99.8% prediction accuracy compared to other machine learning approaches and the decision tree is constructed through the respective regression model. Decision tree has the ability to handle process parameters systematically and predicts the implications of Citrullus lanatus extract in decreasing the temperature at machine-tool interface during machining operation. This tree structured analysis provides a better inference that delivers flexibility in turning parameters and opens up wider options for operation. Thus, decision tree approach ensures optimized usage of production resources and increases the production capacity through judicial selection of cooling approaches associated with the turning process.

Background Watermelon (Citrullus lanatus) represents the largest cultivated member of the Cucurbitaceae family, showing great relevance from the economic point of view and largely consumed around the world accounting for about 7% of the world area dedicated to the production of vegetables, with 67% of the total quantity produced in China. It is characterized by several bioactive compounds, showing different chemical structures, such as carotenoids, xanthophylls, phenolic compounds, citrulline, and unsaturated fatty acids. The good amount of total polyphenols, vitamin C, citrulline and the excellent supply of lycopene, about 40% compared to raw tomatoes, give a measure of the importance of this fruit respect to the other crops considering the beneficial effects of these compounds on human health. Scope and approach In the last decades, this great interest towards natural bioactive compounds led many researchers to study watermelon as natural source of bioactive compounds, mainly when considering some biological properties, including antioxidant, antimicrobial and anti-inflammatory activities, inhibition or induction of enzymes, inhibition of receptor activities, together with induction/inhibition of gene expression. However, the most of scientific literature on this topic was based on in vitro assays, thus limiting the comprehensive understanding of the real health-promoting outcomes. Key findings and conclusions Therefore, the aim of this review was to present the up-to-date research carried out on watermelon phytochemicals, showing the most important biological activities reported from both in vitro and in vivo trials. Besides, the potential exploitation of watermelon by-products in the green circular economy and food-waste valorization has been discussed.

Two new phenolic glycosides, 2-caffeoyl-3-hydroxy-3-methylbutyric 4′-β- d -glucopyranosyloxy-3′-hydroxybenzyl ester and 2-caffeoyl-3-hydroxy-3-methylbutyric 4′-β- d -glucopyranosyloxybenzyl ester (citrulluside H and citrulluside T) were isolated from young fruits of Citrullus lanatus. Their structures were elucidated by spectroscopic analyses. These constituents exhibited weak antioxidant activity.

Watermelon is an annual fruit crop that faces various biotic and abiotic stresses. Genetic engineering is an efficient tool for improving plant traits that combat environmental stresses. In this study, we have developed an improved Agrobacterium-mediated genetic transformation system for watermelon and the same was evaluated in four cultivars (Arka Manik, Arka Muthu, IIHR-14, and Sugar Baby).Agrobacterium tumefaciens strain EHA 105 bearing binary vector pCAMBIA 1301-bar was used to standardize the transformation protocol. BASTA® 6 mg−1was used to eliminate nontransformed tissues and select transformed shoots. To improve the transformation efficiency, polyamine incorporation in the medium, sonication of explant, and vacuum infiltration were tested. The highest transformation efficiency of 17.3% was achieved with spermidine (15 mg l−1) incorporation in the culture medium, sonicating the explant for 30 s followed by 2 min vacuum infiltration during Agrobacterium-mediated genetic transformation, in the cultivar Arka Manik. The shoot induction and elongation medium containing BA (1 mg l−1), leucine (5 mg l−1), spermidine (10 mg l−1) along with BASTA® were successfully used for regeneration and elongation of shoots, from cotyledonary node. The 2-month-old regenerated putative transformants were subjected for molecular analysis. Histochemical GUS (β-glucuronidase) assay, PCR and southern analysis confirmed the presence of a transgene in the obtained transgenic watermelon lines. This transformation protocol was tested in four cultivars to prove its efficiency, which further confirmed that this genotype-independent direct regeneration–based Agrobacterium transformation protocol could be further explored for improving genetic transformation of watermelon.

In this study carbonized watermelon (Citrullus lanatus) rind (CWMR) was prepared and reported as a low-cost and renewable material for adsorption of methylene blue (MB) from aqueous solution. Sulphuric acid (H2SO4) was chosen as a chemical activator to modify watermelon rind via a one-step chemical activation at relatively low activation temperature (110 °C) for 24 h. The adsorption study in batch mode was performed by taking into account the effects of the CWMR dosage (0.02–0.25 g), solution pH (3–9), initial MB concentration (50–400 mg/L), and contact time (0–300 min). A comprehensive kinetic, equilibrium, and thermodynamic study was carried out. The kinetic results are described by a pseudo-second-order kinetic model, while the adsorption process at equilibrium followed the Langmuir isotherm model with maximum adsorption capacity of 200 mg/g at 303 K. Thermodynamic parameters reveal that the adsorption process is endothermic in nature that is driven mainly by electrostatic, hydrogen bonding, and π–π stacking interactions. These findings indicated that the CWMR developed in this research is an efficient, low cost, and renewable adsorbent for the effective removal of cationic dyes from wastewaters.

Shelf-life improvement of fresh-cut produce such as watermelon can be guided by optimizing flavor and consumer liking, while ensuring microbial quality. In this study, the impacts of postharvest processing and packaging technologies on consumer acceptability and flavor profiles of fresh-cut watermelon were evaluated. The treatments included post-cut sanitation spray (with and without), modification of the headspace gas composition (ambient and modified atmosphere), lidding film permeability (perforated and non-perforated), storage temperature (3 and 7 °C) and storage period (1, 6 and 8 d). Odor-active compounds of both fresh and stored watermelon were identified by olfactometry. Changes in key odor-impact volatile compounds were measured using solid phase microextraction-gas chromatography-mass spectrometry and proton transfer reaction-mass spectrometry. Changes in the volatile composition of samples stored at 3 °C were correlated to the consumer sensory scores for color, fresh appearance, odor, firmness, flavor, and taste. Fresh-cut watermelon packed in ambient air, sealed with non-perforated lidding film, and stored at 3 °C for both 6 and 8 d received the highest flavor and overall liking scores compared to modified atmosphere (5 %O2 and 10 %CO2). Further improvement of flavor freshness and overall acceptability was achieved when the post-cut sanitation step was removed. Results indicated that the shelf-life, as judged by overall perceived quality, can be increased from 6 to 8 d by manipulation of processing and storage conditions without compromising flavor and consumer acceptance. The study confirmed the usefulness of linking consumer acceptability to volatile measurement as a research tool to optimize product improvement.

This study was conducted at the apiary of the Beekeeping Research Section at the Sakha Agricultural Research Station, ARC, Kafrelsheikh, and other apiaries in Kafrelsheikh province, during two successive years 2015 and 2016. The study aimed to survey nectar and pollen floral resources in Kafrelsheikh province. Ninty seven plant species belonging to 33 families were recorded as nectar sources, and 82 plant species belonging to 36 families were recorded as pollen sources during the whole year. The largest amount of monthly trapped pollen was obtained during May followed by August. It can be concluded that, beekeepers in Kafrelsheikh province can harvest good honey yield at the end of blooming seasons of citrus (Citrus spp.) during March and April, Egyptian clover (Trifolium alexandrinum L.) during May and June, loofah (Luffa aegyptiaca Mill.) during June to October, cotton (Gossypium spp.) during July and August, and banana (Musa spp.) during August and September. They also, could be trapping pollen loads collected from faba bean (Vicia faba L.) and flax (Linum usitatissimum L.) during January to March, date palm (Phoenix dactylifera L.) during March and April, Egyptian clover during May and June, summer seed watermelon (Citrullus lanatus var. colothynthoides L.) during June and July, loofah and maize (Zea mays L.) during June to November. Keywords: Flora, Honeybee, Kafrelshiekh, Nectar, Pollen

MADS-box genes comprise a family of transcription factors that function in the growth and development of plants. To obtain insights into their evolution in watermelon (Citrullus lanatus), we carried out a genome-wide analysis and identified 39 MADS-box genes. These genes were classified into MIKCc (25), MIKC*(3), Mα (5), Mβ (3), and Mγ (3) clades according to their phylogenetic relationship with Arabidopsis thaliana and Cucumis sativus; moreover, these 25 genes in the MIKC clade could be classified into 13 subfamilies, and the Flowering Locus C (FLC) subfamily is absent in watermelon. Analysis of the conserved gene motifs showed similar motifs among clades. Continuing chromosomal localizations analysis indicated that MADS-box genes were distributed across 11 chromosomes in watermelon, and these genes were conditioned to be differentially expressed during plant growth and development. This research provides information that will aid further investigations into the evolution of the MADS-box gene family in plants.

The potentiality of Citrullus lanatus fruit (CLF) extract containing several phytochemicals (e.g., citrulline, hesperetin, resveratrol and riboflavin) for mitigating the corrosion of mild steel specimens in subjection to 1 M HCl was assessed from integrated experimental and electronic/atomic level theoretical perspectives. The corrosion inhibition characteristics were examined applying electrochemical (EIS and polarization) and surface morphological (SEM, AFM, contact angle) techniques. Additionally, the presence of major phytochemicals in CLF extract was explored by FT-IR spectroscopy combined with UV–Visible analyses. Based on electrochemical results, with the use of 800 ppm CLF extract 91% inhibition capacity was derived. The potentiodynamic polarization clarified the mixed inhibition effect of CLF extract with prevalence cathodic inhibition. Also, the graphical SEM/AFM results disclosed that the interactions of CLF extract molecules with steel surface greatly influenced the prevention of surface damage. The outcomes resulted from molecular simulation and quantum mechanics analyses further reflected the CLF extract compounds adsorption on steel surface.

Fruit cracking in watermelon (Citrullus lanatus) causes a great economic loss. To understand the molecular mechanisms underlying watermelon fruit cracking, the differentially expressed genes (DEGs) between resistant and susceptible-cracking watermelon were analyzed using transcriptome sequencing. We selected the parent inbred W11 (resistant-cracking) and W13 (susceptible-cracking), and Near-Isogenic Lines W96 (resistant-cracking) and W85 (susceptible-cracking) as materials. Differentially expressed genes (DEGs) analysis showed that 290 DEGs had detectable in “W11” VS “W13”, while 165 DEGs had detectable in “W96” VS “W85”. There were 56 DEGs between the four samples. Additionally, 14 DEGs related to fruit cracking were identified from the transcriptome. Only 8 DEGs among them, were involved in 14 KEGG pathway. The expression patterns of the 14 DEGs related to fruit cracking were analyzed by qRT-PCR to explore their putative functions. This transcriptome dataset will aid in understanding and carrying out future studies on the molecular basis of fruit cracking and contribute to watermelon breeding.

Watermelon bud necrosis orthotospovirus (WBNV), is a distinct virus species in the genus Orthotospovirus, family Tospoviridae and order Bunyavirales. Orthotospovirus is the only genus in the family whose members infect plants, while viruses in other genera infect invertebrates. WBNV is prevalent in most of the watermelon growing Indian states and therefore, its prevalence in the Indian subcontinent cannot be ignored. Quasi-spherical enveloped virions are 80–110 nm in size. Virion composed of genomic RNAs with nucleoprotein, viral polymerase, and a lipid envelope with glycoprotein (GN/Gc) spikes. WBNV shares common genomic features with other orthotospoviruses. The tri-segmented genome is referred to as the small (S) (3.4 kb), the medium (M) (4.7 kb), and the large (L) (8.9 kb) RNAs. S RNA uses ambisense coding strategy and codes for non-structural (NSs) protein in the viral (v) sense and nucleocapsid (N) protein in the viral complementary (vc) sense. Similarly, M RNA uses ambisense coding strategy and codes for a precursor for the GN/GC in vc sense and movement (NSm) protein in v sense. L RNA is of negative polarity and codes for the RNA-dependent RNA polymerase (RdRp). WBNV is known to be transmitted by Thrips palmi (Order: Thysanoptera; Family: Thripidae; melon thrips) in a persistent propagative manner. WBNV is sap transmitted to various experimental hosts belonging to several families viz., Amaranthaceae, Asteraceae, Chenopodiaceae, Cucurbitaceae, Fabaceae, Pedaliaceae, and Solanaceae. WBNV has limited natural host range, predominantly confined to bitter gourd (Memordica charantia), chrysanthemum (Chrysanthemum indicum), chilli (Capsicum annum), cucumber (Cucumis sativus), muskmelon (Cucumis melo), pumpkin (Cucumis sativus), ridge gourd (Luffa acutangula), tomato (Solanum lycopersicum), and watermelon (Citrullus lanatus). Besides these main hosts, Abutilon indicum, Amaranthus spp., Euphorbia heterophylla, Malvastrum coromandelium, and Parthenium hysterophorus serve as green-bridge for virus perpetuation. WBNV symptoms include mottling, yellowing, necrotic streaks on vines, shortened internodes, stunted plant growth, severe stem and bud necrosis and dieback of the buds. Late season infection results in deformed fruits with necrotic local lesions. In India, WBNV resistant watermelon varieties are not available. A wild relative of watermelon, Citrullus colosynthis, has recently been identified as a resistant source, which is used in the breeding program as part of integrated disease management (IDM) strategies. IDM strategies include clean crop cultivation, border cropping, intercropping, use of plastic mulches, crop rotation, and control of thrips can alleviate the effect of WBNV in the Indian subcontinent. Recently, non-conventional management option of development of putative transgenic resistance has been worked out and found WBNV N gene is effective in conferring resistance in watermelon.

Watermelon is an L-citrulline-rich fruit that has been used as a supplement to increase L-arginine in plasma, which in turn plays a critical role in the synthesis of nitric oxide, a molecule that regulates vascular tone. Watermelon rind, similar to its pulp, presents a high L-citrulline content, yet a lower concentration of sugar, which would be more convenient for individuals who need to refrain from excessive sugar ingestion (i.e., diabetics and obese individuals). Further, ingestion of watermelon rind can be a sustainable alternative to increase plasma L-arginine, given that rind of fruits is commonly discarded. Therefore, we evaluated the effect of ingestion of a product derived from watermelon rind and pulp (microencapsulation in spray drier) on plasma amino acids (L-citrulline, L-arginine and L-ornithine), glucose, and insulin. Eleven participants (28.36 ± 5.70 years) were enrolled in a single blind, cross-over and randomized study. They ingested microencapsulated watermelon rind and pulp (containing 4 g of L-citrulline) plasma amino acids, glucose, and insulin were evaluated before and 30, 60, 90 and 120 min after ingestion. It was observed that both microencapsulated watermelon rind and pulp increased L-citrulline through 120 min and microencapsulated watermelon rind significantly increased L-arginine at 30 min. In addition, microencapsulated watermelon rind and pulp similarly increased plasma glucose and insulin levels. In conclusion, these findings suggest that both microencapsulated watermelon rind and pulp are effective to increase plasma L-citrulline and microencapsulated watermelon rind effectively increases plasma L-arginine. In addition, rind and pulp promote similar changes on plasma glucose and insulin.

This work presents a green synthesis of silver nanoparticles (AgNPs) using Citrullus lanatus juice extract. The biologically synthesized AgNPs and functionalized AgNPs using L-cysteine (Cys-AgNPs) were characterized by the UV-Vis spectroscopy, the FT-IR spectroscopy, and the scanning electron microscopy (SEM) analysis. The surface-plasmon resonance (SPR) bands of the AgNPs and Cys-AgNPs and appears at 420 and 415 nm, respectively. The SEM image revealed that the particles had a spherical shape and size distribution of 20–40 nm. Application of Cys-AgNPs in terms of heavy metal selectivity showed that it exhibited selectivity against nickel(II) which was confirmed by the color change from yellow to orange and the appearance of a new SPR band at 455 nm. The predicted structures of AgNPs and Cys-AgNPs showed that the complexes were formed through the electrostatic interactions and the shift of the SPR band from theoretical calculations are in accordance with experiment. Accordingly, this eco-friendly approach showed the successful application of the biologically green synthesized AgNPs modified by the L-cysteine addition for colorimetric detection of nickel(II). This proposed method could be considered as an efficient probe for the colorimetric sensing of nickel(II) with simplicity, rapidity, low cost and environmental reservation.

Citrullus lanatus seed is an important but neglected seed rich in essential fatty acids. The study sought to investigate in silico and in vivo antifungal activity of some bioactive compounds of Citrullus lanatus (watermelon) seed oil (CLSO) on oral candidiasis induced by Candida albicans in immunosuppressed female albino rats and to predict the Absorption, Distribution, Metabolism and Excretion (ADME) properties of isolated natural compound. Docking studies was performed using standard procedure, standard microbiological and histopathological techniques was employed for study of in vivo antifungal activity of the oil; as well as renal function tests at days 7 and 14 post-infection treatments. Treated groups were compared with that of the control groups. In vitro studies showed varied zone of inhibitions at different concentrations. Ligand-protein interaction showed better binding activity between Palmitic acid and SAP-5 as well as CYP51 when compared with fluconazole (reference drug). Treatment with CLSO showed that there was a significant reduction in the kidney fungal burden (cfu/ml/g) of rats treated with CLSO after 14 days post-infection treatment, compared to group 2 (untreated control) rats. Histomorphology of group 2 showed multifocal aggregation and widespread distribution of fungal blastospores when compared with CLSO-treated groups, which had minimal fungal blastospores in the renal tissues. Thus, in silico and histological data agreed with the findings in microbiology. Furthermore, within the CLSO treated group, a significant increase in the serum concentrations of creatinine was observed, while no significant difference in blood urea values was recorded after day 14 post-infection study. Linoleic and palmitic acid could be considered as a potential antifungal drug candidate with palmitic acid playing a significant role.

An antimicrobial characterization along with thermal, structural, functional properties of L. acidissima and C. lanatus seeds were studied. Key proteins were identified in L. acidissima and C. lanatus seeds. The antimicrobial activity of L. acidissima protein hydrolysates was comparatively better than those of C. lanatus against the indicator strains used, i.e., Salmonella typhi, Pseudomonas aeruginosa, Escherichia coli and Klebsiella pneumonia. The denaturation temperature for L. acidissima and C. lanatus protein hydrolysates were 92 and 72 °C, respectively. The FTIR analysis showed the presence of amide A, amide I, amide III and amide VI bands in the protein hydrolysates. The emulsifying activity index of the L. acidissima and C. lanatus seed protein hydrolysates were 53 and 29 m2/g, respectively. The emulsifying stability index for both hydrolysates was around 79%. The LCMS profile showed 4 proteins in L. acidisssima and 21 proteins in C. lanatus.

This study addresses a soil improvement technique using plant-derived urease-induced calcium carbonate (CC) precipitation (PDUICCP) as an alternative to microbially induced carbonate precipitation (MICP). A crude extract of crushed watermelon (Citrullus lanatus) seeds was used as the urease source along with calcium chloride (CaCl2) and urea (CO (NH2)2) for CC precipitation. Test specimens (φ = 2.3 cm, h = 7.1 cm) made from commercially available Mikawa sand (mean diameter, D50 = 870 µm) were cemented, and estimated unconfined compressive strength (UCS) of several kPa to MPa was obtained by changing the concentration of CaCl2- urea, urease activity, curing time, and temperature. The increase of curing time and that of the CaCl2-urea concentration from 0.3 M to 0.7 M caused an increase in estimated UCS value. The average estimated UCS obtained after 14 days’ curing time for 0.7 M CaCl2-urea and 3.912 U/mL urease was around 3.0 MPa and for 0.3 and 0.5 M CaCl2-urea and 0.877 U/mL urease, it was around 1.5–2.0 MPa at 25 °C. By changing each of the abovementioned parameters, it may be possible to apply this method for strength improvement of loose sand, to mitigate the liquefaction, protection and restoration of limestone monuments and statuaries, and artificial soft rock formations. Crude urease from crushed watermelon seeds has the potential to replace commercially available urease for carbonate precipitation and for use as a low environmental impact type soil improvement method.

Accurate determination of total dietary fiber (DF) and its soluble (SDF) and insoluble (IDF) fractions is relevant for food analysis research and nutritional labelling. AOAC integrated DF methodology (AOAC 2011.25, IM) has procedure differences compared to the traditionally used AOAC method (991.43, TM), resulting in different DF quantification. However, IM has been mostly performed for cereal-based products and its application in sources such as fruit products needs to be studied. The aim of this study was to compare the DF content obtained by TM with that achieved using IM in pulps and peels of banana (Musa paradisiaca), mamey sapote (Pouteria sapota), mango (Mangifera indica), Meyer lemon (Citrus meyeri), orange (Citrus sinensis), prickly pear (Opuntia ficus-indica), tamarind (Tamarindus indica), and watermelon (Citrullus lanatus). Samples containing high starch (banana and its peel, mamey sapote and mango pulp) showed higher IDF values when IM was used. Differences were observed when pectinaceous fruits (orange, Meyer lemon, mango and prickly pear) were assayed, since soluble and insoluble pectins are underestimated by TM. Fruits with a high content of non-digestible oligosaccharides showed higher SDF values when assayed by IM. The use of IM in fruits and their by-products provides relevant information about DF fractions and reduces DF underestimations typically observed when assayed by TM.

Two-hundred-twenty-five BC1 generations were obtained from backcrossing F1 of the shallow green rind, red flesh, no bitterness cultivated watermelon inbred line W1-1 and the dark green rind, white flesh, bitter wild species PI186490 hybrid as well as their female parents. CAPS makers spanning the whole genome were used to genotype every individual based on whole-genome resequencing data. Watermelon genetic linkage maps of 186 CAPS markers corresponding to 11 chromosomes were constructed, spanning a total distance of 1468.09 cM. Genetic analysis and gene mapping were performed using the flesh color, rind pattern and flesh bitterness as 3 qualitative traits. The results showed that wide rind stripes and flesh bitterness were controlled by a dominant gene, with red flesh recessive to white flesh, and 3 loci were identified related to the 3 fruit traits mentioned above. This study provides a theoretical basis for molecular marker-assisted selection of desirable watermelon fruit traits.

Interspecies specific interactions are generally regarded as drivers of plant productivity in multispecies agroecosystems. Complementary use of resource in diverse communities can enhance community productivity through optimal use of plant-available resources and positive interactions such as facilitation can ameliorate high abiotic stress conditions. We studied the effects on physiological response, leaf traits and water use efficiency of a multifunctional species intercropping system consisting of peanut (Arachis hypogaea L.), watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai], okra [Abelmoschus esculentus (L.) Moench], cowpea [Vigna unguiculata (L.) Walp.], and pepper (Capsicum annuum L.) planted alone or in various intercropping combinations in a low fertilizer input system in the peak of summer heat in Texas. Differences in gas exchange measurements were detected only in watermelon in year 2 of the study when okra was the dominant crop. This same year watermelon specific leaf area (SLA) was significantly higher when okra was present in a treatment and particularly in the three and four species combinations, Wpwo and Wpwoc, 27.5 and 31.0 m2 kg−1, respectively, as compared to watermelon grown in monoculture, strip intercropped with peanut (Spw) and within row intercropped with peanut (Wpw), 20.4, 20.1, and 19.8 m2 kg−1, respectively. This corresponds with an increase watermelon leaf N concentration and a decrease in leaf C:N ratio in Wpwo and Wpwoc treatments. No differences in d13C composition, a measure of water use efficiency over the leaf lifespan, were detected across cropping system for each species. Water use efficiency based on per plant production (WUEyield) indicated an increase in water use efficiency in dominant crops such as watermelon in 2011 and okra in 2012, but a reduction in WUEyield subordinate crops such as cowpea and pepper both years of the study. Peanut grown in monoculture and strip intercropped with watermelon had significantly lower leaf water potential values in 2012, −2.2 and −2.1 MPa, respectively, as compared to intercropping systems increasing in level of integration (Wpw = − 1.1, Wpwo = − 0.6, Wpwoc = − 1.3, Wall = −1.1 MPa), indicating peanut benefited from alterations to microclimate and facilitative interactions with companion crops in some intercropping systems through a reduction in plant water stress. The results from this study suggest there may be a benefit to a multifunctional intercropping system in the form of increased food production per unit of water input in dominant crops and reduced water stress for some component species. This is important to producers; showing a method to increase overall crop production without increasing water inputs.

A physical-chemical characterization, followed by the measurement of biochemical traits, was performed on two novel mini-watermelon varieties, ‘Cuoredolce®’ and ‘Rugby’, selected for the high content of sugars and carotenoids, at three different maturation stages. The aim of this work was to define the fruit quality and to find potential external maturity indicators. The two cultivars resulted different in precocity and ‘Rugby’ was more near to full ripeness from the early stage considered. As expected, carpometric parameters showed the highest predictive validity of internal quality, being in both varieties positively correlated with SSC (soluble solids content), JU (percent juice), β-carotene, Car/Lyc (β-carotene/lycopene) ratio and sucrose, and negatively with firmness and lycopene. Multivariate analysis of physical-chemical parameters and biochemical traits together with the output of E-nose selected sensors showed the relationships between W3S (methane-aliphatic) and W6S (hydrogen) sensors and sugar composition and pulp firmness and between W2W (aromatic and sulfur organic compounds) and W1W (terpenes, sulfur organic compounds) sensors and fermentative metabolites, the prevalent headspace compounds. The changes of Car/Lyc with ripening suggest that in ‘Cuoredolce®’ there is a more efficient conversion of lycopene to β-carotene at earlier ripening stage. The high sugars content defines the good eating quality of these novel mini-watermelons.

Vanadium (V) is the fifth most abundant transition metal, elevated levels of V are hazardous to plants. Boron (B) is an essential micronutrient for plants and can mitigate heavy metal toxicity. However, the mechanism used by B to promote tolerance to vanadium is unknown. In this study, a combination of physiological and gene expression analysis was used to explain mechanism of B (75 µM) induced V (40 mg L-1) stress tolerance in watermelon. V stress severely reduced root and shoot growth and increased the accumulation of ROS. B application improved tolerance to V by enhancing the expression of B transporter genes (ClaNIP5;1–1, ClaNIP5;1–2, ClaBOR4) that facilitated B uptake and transport while restricting V transport in plant tissues. At cellular level, the higher V retention in leaves was achieved by cell wall chelation, whereas, the higher V exclusion in vacuole of root cell was driven by elevated vacuolar H+-ATPase, H+-PPase activities, and transcript level of ClaVHP1;1, ClaPDR12–1 and ClaPDR12–2 genes facilitated by B application. Moreover, B application reduced tissue ROS cascade by enhancing antioxidant enzymatic activity and expression of superoxide dismutase (ClaCSD1–1, ClaCSD1–2, ClaCSD3, ClaMSD1) and catalase (ClaCAT2–1, ClaCAT2–2) genes that enhanced the defense mechanism of the V treated plants, improved root and shoot growth and tolerance index of watermelon. In conclusion, we demonstrate that ameliorative effect of B in tolerance to V of watermelon was based on B homeostasis and improved antioxidant defense system. These findings might help to increase watermelon production in V polluted soils.

The nutritional quality of many fruits and vegetables is regulated by pre-harvest management factors that can be manipulated to attain desired quality standards. In this study, the impact of seed nanopriming on the phytochemical composition of watermelon was studied. Seeds of two watermelon varieties namely: River Side (diploid) and Maxima (triploid) treated with two nanomaterials (silver nanoparticle and turmeric nanoemulsion) along with untreated seeds were grown in five locations over two seasons. Physico-chemical properties and phytochemical profiles were assessed after mature fruits were harvested and stored at 23 °C for 0, 10, and 20 d. Key physico-chemical characteristics that were impacted by storage included fruit weight, rind thickness, pH, and soluble solid content. Similarly, levels of health-promoting compounds such as carotenoids, l -citrulline, and total ascorbic acid were maintained and/or enhanced in watermelons after 10 d of storage compared to untreated fruits at harvest. However, l -citrulline (10.40 g/kg) and total ascorbic acid (57.52 g/kg) was significantly reduced in watermelons after 20 d of storage (8.6 and 19.09 g/kg, respectively) regardless of treatment and location (p

The GDSL esterase and lipase families play important roles in abiotic stress, pathogen defense, seed development and lipid metabolism. Identifying the lipase activity of a putative GDSL lipase is necessary to determine its function. Systematic analysis of the GDSL gene family is still lacking for Citrullus lanatus. In this study, we identified 65 watermelon GDSL-type esterase/lipase genes and divided these genes into 6 clades based on phylogeny. The phylogenetic relationship of watermelon GDSL genes and Arabidopsis thaliana GDSL esterase/lipase genes was also determined, and these genes were divided into four groups related to morphological development, abiotic stress response, pathogen defense, and secondary metabolism. The chromosomal location of these genes revealed that they are distributed unevenly across all eleven watermelon chromosomes. Analysis of duplication events suggested that segmental duplication and tandem duplication were the major driving forces of GDSL family evolution. Synteny analysis indicated that GDSL genes in watermelon were highly homologous to those in A. thaliana, melon and cucumber. Transcriptome analyses showed the organ-specific and common expression of the GDSL genes in the root, stem and leaf organs and revealed that some of the GDSL genes are responsive to gummy stem blight inoculation, suggesting the possible involvement of these genes in disease stress–response pathways. Our results provide a basis for selecting candidate watermelon GDSL genes for further studies to determine the biological functions of the GDSL genes in watermelon.

This work reports the sensory evaluation of the aroma of a forward osmosis (FO) concentrate of watermelon (Citrullus lanatus) juice. The FO concentrate's overall aroma liking and individual aroma attributes were compared to those of fresh-cut watermelon and a conventional thermally-evaporated concentrate prepared from the same source juice (“thermal concentrate”). For the aroma rating, a structured 15-point hedonic scale was used, and for aroma profiling a check-all-that-apply (CATA) approach was taken. The thermal concentrate was found to have degraded aroma quality. In contrast, FO concentrate had a highly-liked aroma, and it outperformed the thermal concentrate in the hedonic rating. There was no significant difference (p

Traditionally, Citrullus lanatus is known to have protective properties in kidney diseases and for having the ability to clear urine. Current study aims to validate the traditional uses of C. lanatus by evaluation of anti-urolithiatic and diuretic activities using in vivo and in vitro experiments. Male Wistar rats were used for in vivo anti-urolithiatic and diuretic activities. Supersaturated solution of calcium and oxalate was used for in vitro crystallization study. Hematoxylin & eosin staining was used for histopathological evaluation of kidney. In the in vivo rat model of urolithiasis, the pulp extract reduced calcium oxalate (CaOX) crystal count in both kidney and urine. The pulp extract also increased the urinary pH and output, and prevented the weight loss. Serum analysis showed elevation in creatinine clearance and reduction in urea and creatinine levels. Urinary analysis demonstrated that pulp extract restored altered phosphate, calcium, oxalate, and citrate levels. In the in vivo rat model of diuresis; the pulp extract produced diuresis, reduced serum chloride levels, and elevated urinary sodium and chloride levels. In the in vitro crystallization experiment, pulp extract inhibited the aggregation phase. Seed extract failed to show any convincing results. GC-MS analysis revealed the presence of steroids and alkanes as the major constituents of pulp extract, which might be responsible for anti-urolithiatic activity; however, further studies are required for isolation and identification of active constituents. Current study validated the traditional uses of watermelon and demonstrated that pulp extract possessed significant anti-urolithiatic and diuretic activities.

The present study aimed to evaluate different inoculation methods of Fusarium oxysporum f. sp. niveum in watermelon and the reaction of accessions from this crop. Firstly, seven inoculation methods using conidia were tested on the susceptible cultivar Sugar Baby, including the standard dipping method. The methods initially tested were not efficient; therefore, we tested a new methodology using chlamydospores which are fungus survival structures. After the production of chlamydospores in vermiculite enriched with liquid culture media potato and sucrose (PS), the new method was tested on an experiment comparing inoculation by conidia and chlamydospores. For the conidia method, the plants were inoculated after their final leaf formed. For chlamydospores, inoculations were done in plants or sowed seeds. The use of chlamydospores in sowed seeds was effective for the inoculation of Fusarium oxysporum f. sp. niveum in watermelon and showed the highest severity scores in relation to the others methods. The inoculation method using chlamydospores also obtained the shortest means of root and shoot length in the cultivars Charleston Gray and Sugar Baby. Thus, using this methodology, 25 accessions from the watermelon germplasm were evaluated 21 days after inoculation with a grading scale. Eight accessions were classified as resistant, corresponding to 32% of accessions evaluated. Eight other accessions received the highest score of severity, proving the efficiency of the methology to evaluate the reaction to the disease.

Biobased plasticizers for polymers is a necessity to replace conventional phthalates based plasticizers. In the present study, Citrullus lanatusseed oil (ECLO) was epoxidized in a magnetically stirred reactor. Polyvinyl chloride (PVC) films were synthesized using different concentrations of ECLO. At 40% of ECLO, films showed better surface morphology and exhibited maximum strength and elongation at break. Plasticized PVC film shown tensile strength of 18.6 MPa and elongation at break of 136.18%. No migration was observed in water, designating hydrophobic characteristics of the films. In gasoline, acid (Acetic acid) and alkali (Sodium hydroxide), plasticized samples exhibited a low resistance for migration. X-ray diffraction analysis confirmed no change in crystallinity of PVC after addition of ECLO. Thermogravimetric analysis presented the plasticized PVC films are thermally stable. Differential scanning calorimetry established the plasticizing effect of ECLO as a glass transition temperature (Tg) of plasticized films was shifted to a lower temperature.Furthermore, Fourier transform infrared spectroscopy revealed interaction of ECLO with PVC as peaks of C–Cl bond (833 cm−1) and C O stretch (1739 cm−1) were detected. Thus, the present study delivered a better substitute for phthalates as it endorses the application of ECLO in the PVC blend as a plasticizer.

Spectroscopic techniques utilizing FTIR, 1 H and 13 C NMR spectral fingerprints of the neat oils, as well as standard titrimetric and GC–MS analyses were all employed to determine the quality parameters and fatty acid (FA) profiles for Soxhlet-extracted seed oils of four indigenous plants from Botswana: Tylosema esculentum (morama), Schinziophyton rautanenii (mungongo), Citrullus lanatus (kgengwe) and Bauhinia petersiana (mogose). The physicochemical parameters and FA composition obtained from spectroscopic methods were found to be similar to those obtained from classical procedures indicating that oil quality parameters can reliably be obtained from spectroscopic data. The FA analysis showed the presence of 73–84% unsaturated FAs in the four seed oils. In addition, spectroscopic data clearly established the presence of the uncommon tri-unsaturated FA, α -eleostearic acid ( α -ESA) in mungongo seed oil which was quantified as 25% by 13 C NMR. Generally, the high levels of unsaturated FAs in the oils indicate their suitability in health food supplements. Industrial relevance The four plants studied are highly treasured in the areas where they grow due to the fact that they have for centuries provided food security, and means of livelihood for populations living in the Kalahari Desert and other marginal regions of the southern Africa region. Currently, there is a drive to add value to such often underutilized plants to aid in poverty alleviation by processing and marketing the products as healthy food supplements or cosmetic formulations. To this end, reliable methods for characterization and comparison of the FA composition of the seed oils from different geographical locations is required. The development of rapid, non-destructive spectroscopic techniques that can be applied directly on the neat oils is therefore an important venture.

The oil obtained from the seeds of Citrullus lanatus (Thunb.) Matsum. & Nakai (Kalahari melon) is highly sought after in the cosmetic industry as a prized ingredient to maintain healthy skin. Seed oils contain a range of fatty acids that may be beneficial upon topical application to the skin. The quantification of the fatty acids was done using two dimensional gas chromatography coupled to mass spectrometry (GC × GC–MS). The safety (irritancy potential test) and efficacy (transepidermal water loss (TEWL), hydration and occlusivity tests) of topically applied Kalahari melon seed oil on healthy Caucasian adult female volunteers (n = 20) was determined. Skin irritation and dryness were determined by visual scoring using a 2 × magnifying lamp while Chromameter®, Aquaflux® and Corneometer® instruments were used to quantify the irritancy level, TEWL and hydrating properties of Kalahari melon oil, respectively. The occlusive effect of the oil was assessed using Aquaflux® and Corneometer® instruments. Four major fatty acids, linoleic acid (51.4%), oleic acid (36.7%), stearic acid (6.3%) and palmitic acid (5.6%), were quantified using comprehensive GC × GC–MS analysis. Kalahari melon seed oil was non-irritant to the skin when topically applied (observed at 24, 48, 72 and 96 h). Aquaflux® and Corneometer® results showed that the application of Kalahari melon seed oil resulted in reduced TEWL and increased moisture retention. The non-irritant, hydrating and moisturising effects of Kalahari melon seed oil observed in this study justifies its incorporation into cosmetic products.

Citrullus lanatus (camel melon) is an important summer weed of Australian fallows, and can rapidly develop monocultural stands in sandy soils receiving adequate soil moisture. As a general review on the biology of C. lanatus , this paper reviewed the current published literature (including our recent published studies) and also summarised extensive field and laboratory studies performed on its biology, phenology and management in the South-West Slopes of New South Wales. Recent population genetics studies conducted in Australia have shown that the species is monotypic, and was introduced as a single colonisation event in the mid 1800's. Our studies showed genetic diversity in C. lanatus to be non-existent across Australia and invasive ranges and highest in the native range in Africa. Further genetic analyses have shown the species in Australia is identical to Citrullus lanatus var. citroides , the citron melon, native to Africa and now naturalised across Africa, Asia and North America, where it is a weedy nuisance or occasionally a food source for livestock and humans. Although limited genotypic diversity may facilitate potential biocontrol strategies for Citrullus lanatus in Australia, biocontrol may be difficult due to its close genetic similarity to commercial watermelon, a major horticultural crop in Australia and more globally. In Australia, field germination was observed to occur during a two to three-month period between late spring and summer, when warm soil temperatures occurred and field establishment was typically observed after significant rainfall events and was associated with soil moisture availability. Controlled environment seed dormancy findings indicated that dormancy was significantly reduced by storage at ambient laboratory temperatures over eighteen months. Seed dormancy was transient and appeared to be both physical and physiological in nature, and was dependent on the period of after-ripening during the post-harvest period. Key reproductive attributes, including high seed production, self-compatibility and pollination facilitated by several non-specific pollinators have likely resulted in increased spread of this weed in Australia and more globally. Management of C. lanatus is achieved using IWM strategies including pre and post-emergent applications of herbicides as well as limiting fruit production by cultural practices including mowing, grazing and cultivation.

The genetic basis of fruit size and shape was investigated for the first time in Cucurbita species and genetic loci associated with fruit morphology have been identified. Although extensive genomic resources are available at present for tomato (Solanum lycopersicum), cucumber (Cucumis sativus), melon (Cucumis melo) and watermelon (Citrullus lanatus), genomic databases for Cucurbita species are limited. Recently, our group reported the generation of pumpkin (Cucurbita pepo) transcriptome databases from two contrasting cultivars with extreme fruit sizes. In the current study we used these databases to perform comparative transcriptome analysis in order to identify genes with potential roles in fruit morphology and fruit size. Differential Gene Expression (DGE) analysis between cv. 'Munchkin' (small-fruit) and cv. 'Big Moose' (large-fruit) revealed a variety of candidate genes associated with fruit morphology with significant differences in gene expression between the two cultivars. In addition, we have set the framework for generating EST-SSR markers, which discriminate different C. pepo cultivars and show transferability to related Cucurbitaceae species. The results of the present study will contribute to both further understanding the molecular mechanisms regulating fruit morphology and furthermore identifying the factors that determine fruit size. Moreover, they may lead to the development of molecular marker tools for selecting genotypes with desired morphological traits.

Several biotic and abiotic factors may cause losses during the production of watermelon, Citrullus lanatus (Thunb.) Matsum. & Nakai, but there are currently few tools available to quantify losses in the different components of crop production. A crop life table can be used to understand the factors that regulate losses during crop production to establish a sustainable crop management programme. The aim of this study was to identify the critical components and quantify the key factors affecting yield loss during watermelon production using a crop life table as a tool. In 2011 and 2012, watermelon production loss factors in the field were evaluated using a completely randomised experimental design with 12 replicates, and each replicate consisted of a 64-m 2 area containing 4 rows with 4 holes per row. The spacing was 2 × 2 m, and each hole initially contained 2 watermelon plants. The loss factors of physiological disturbance and insect, fungal, and bacterial attack were identified and quantified to develop a crop life table, and the primary factors regulating total watermelon yield losses were found to be flower abortion, abnormal fruits, and plant death caused by the fungus Didymella bryoniae . Watermelon yield losses are highest during rainy and humid seasons, and the results of this study show that pests and plant physiological disturbance should be jointly managed to attain higher watermelon crop yields.

Five agro-industrial wastes (AIW) were selected to verify their potential as low cost substrate to produce α-amylase enzyme by bacterial strains using solid state fermentation (SSF) and submerged state fermentation (SMF). Among the AIW used strawberry leaves and watermelon rind produced the maximum α-amylase production under SMF by B.subtilis and B. licheniformis, respectively. Co-culture of B.subtilis and B. licheniformis (1:1) on watermelon rind (Citrullus lanatus) improved α-amylase production by 176.3% and 329.2%, respectively compared to mono culture of B.subtilis and B. licheniformis. Decreasing agitation speed to 100 rpm increased the production by 58.1%. In addition, the pretreatment of WMR with different methods before fermentation inhibited the enzyme production. Using two steps of statistical factorial design (Plackett-Burman and Central Composite) to optimize the production medium enhanced α-amylase production by 10.3-fold. The produced α-amylase could effectively hydrolyze AIW, however the highest saccharification yield with the highest reducing sugar (75% and 15 mg/ml) were obtained using cantaloupe peel (Cucumis melo). It is superior to use cantaloupe peel as a novel AIW for saccharification produced glucose (78.3%) and uronic acid (21.3%). Moreover, using Central Composite design to optimize saccharification condition of cantaloupe peel enhanced the yield of reducing sugar by 3.73-fold.

In a first report, watermelon ( Citrullus lanatus ) landraces from diversity rich Indo-Gangetic plains and arid regions of India were characterised using watermelon specific SSR markers. Thirty eight landraces were compared with germplasm of diverse origin comprising of cultivars, landraces and wild types. Significant differences were observed for days to first fruit maturity, average fruit weight, fruit number, total fruit yield, TSS and lycopene content. Thirty three polymorphic SSRs generated 120 bands with a mean of 3.63 per marker. Average PIC value was 0.46. Observed heterozygosity (0.50) was more than expected heterozygosity (0.45). Neighbour joining tree based on SSR analysis grouped accessions into seven clusters. Wild types formed a distinct cluster. Landraces showed genetic intermediateness with both the wild and cultivated watermelons. Combined morphological and molecular analysis revealed modern cultivars from USA, China, Japan and South Korea genetically resembled with each other. Hybridisation between landraces and exotic cultivars can be exploited to expand the genetic variability and introduce new traits in the breeding programs.

Uranium (U) is a radioactive and highly toxic metal. Its excessive concentrations in the aqueous environments may result in severe and irreversible damage. To fight this hazard, a raw biochar was prepared from Citrullus lanatus L. seeds, then characterized and compared with a MnFe2O4 modified biochar, both tested for U(VI) adsorption from wastewater, which was assayed for the first time in this study. The characterization of the adsorbent materials was performed by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) with elemental mapping, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) techniques. The effects of solution pH, concentration of sorbate and sorbents, temperature, time and ionic strength were assessed as regards their influence on U(VI) adsorption. The experimental adsorption data showed good fit to a pseudo-second-order kinetic model (reaching a value of qe = 15.12 mg g−1, R2 = 0.96 at equilibrium), and to the Langmuir isotherm (achieving a maximum score of qmax = 27.61 mg g−1, R2 = 0.96). The maximum adsorption capacity was found at 318 K. The results of the study indicate that the binding of negatively charged functional groups (carbonyls, hydroxyls, and some carboxylic groups) with MnFe2O4 significantly enhanced U(VI) adsorption. In view of the overall results, it can be concluded that the MnFe2O4 modification of the Citrullus lanatus L. seeds biochar could give an efficient alternative adsorbent for U(VI) removal in a variety of environmental conditions, simultaneously promoting resource utilization and good sustainable management of the materials studied, aiding to protect the environment and human health.

This study aimed to develop biodegradable watermelon rind pectin (WRP) films containing 0.5, 1.0, and 1.5 % kiwifruit peel extract (KPE) and investigate their mechanical properties, water vapor permeability, optical properties, and microstructure along with their antioxidant effects on chicken thigh during storage. The obtained WRP films showed an excellent tensile strength and Young’s modulus compared to those of the pectin-based other films. With the increase in KPE concentration, the opacity, elongation at break, and water vapor permeability of the films increased, whereas the rigidity of the films decreased. Moreover, after 9 days of storage, the contents of peroxides and thiobarbituric acid reactive substances in the chicken thigh wrapped with the WRP film containing KPE were lower than those in the unwrapped samples. These results indicate that WRP films containing 1.5 % KPE are potential functional packaging materials that can retard the lipid oxidation in foods.

This study investigated the antioxidant and antimicrobial effects of the peel, rind, pulp and seeds of C. lanatus (watermelon) as well as their respective phytochemical composition. The antioxidant effect was investigated using the DPPH and ABTS assay whereas the antimicrobial activity was evaluated using the well diffusion and broth dilution methods. The results revealed that the peel possessed the highest antioxidant activity whereas the pulp demonstrated the lowest. The peels demonstrated the highest antimicrobial effect, which was followed by the seed and then the rind. The pulp, however, demonstrated the least antimicrobial activity. A strong correlation was observed between total phenolic contents and biological activity. The peels were found to possess the highest content of total phenolics (0.087±0.002 mgGAE/g), which was followed by the seed (0.042±0.003 mgGAE/g) and the rind (0.026±0.003 mgGAE/g). The pulp did not only demonstrate the lowest antioxidant and antimicrobial activities but also had the lowest phenolic content (0.010±0.001 mgGAE/g). The peel and the seed show the presence of flavonoids whereas alkaloids and free reducing sugars were present in all parts of the watermelon fruit. From the results of the current study, it can, therefore, be concluded that among the various parts of the watermelon fruit, the peel has the highest antioxidant and antimicrobial activity whereas the pulp has the least. The peels and seeds are not only potent in their antioxidant and antimicrobial effects but also possess appreciable levels of phenolic compounds relative to the other parts.

Watermelon (Citrullus lanatus) is an important crop worldwide and its growth is highly susceptible to waterlogging. However, it remains unknown how tolerant and intolerant genotypes may respond to waterlogging. To address this issue, we examined a waterlogging tolerant cultivar ‘YL’ in the field and compared it with a sensitive cultivar ‘Zaojia8424’ under waterlogging. ‘YL’ exhibited higher activity of alternative oxidase (AOX), enhanced levels of AOX, and increased KCN-resistant respiration rate, as compared with the sensitive cultivar ‘Zaojia8424’. Accordingly, ‘YL’ had lower contents of O2 −, H2O2 and malonaldehyde, compared with ‘Zaojia8424’. Furthermore, inhibition of AOX pathway by salicylhydroxamic acid exacerbated inhibition of plant growth, promoted the accumulation of O2 − and H2O2, decreased the respiration rate in both cultivars, and diminished the positive effects by AOX observed in ‘YL’. We observed no significant differences between ‘YL’ and ‘Zaojia8424’ in terms of the rate of anaerobic respiration and cytochrome respiration, and expression levels of antioxidant genes. Thus we concluded that the high activity of AOX pathway contributed to the waterlogging tolerance in watermelon via maintaining of the respiratory and alleviation of oxidative damage.

Cucumber green mottle mosaic virus (CGMMV) is a member of the genus Tobamovirus, and is a serious pathogen of Cucurbitaceae crops. Virus-derived small interfering RNAs (vsiRNAs), which are processed by Dicer-like and Argonaute proteins as well as RNA-dependent RNA polymerase, mediate the silencing of viral genomic RNA and host transcripts. To identify the CGMMV derived vsiRNAs and reveal interactions between CGMMV and watermelon host plant, deep sequencing technology was used to identify and characterize the vsiRNAs derived from CGMMV in infected watermelon plants in present study. A total of 10 801 368 vsiRNA reads representing 71 583 unique sRNAs were predicted in CGMMV-inoculated watermelon plants. The CGMMV vsiRNAs were mostly 21 or 22 nt long. The majority of the CGMMV vsiRNAs (i.e., 91.7%) originated from the viral sense strand. Additionally, uracil was the predominant 5′-terminal base of vsiRNAs. Furthermore, the putative targets and functions of some of the CGMMV vsiRNAs were predicted and investigated. The results enhance our understanding of the interaction between CGMMV and the host watermelon and provide molecular basis for CGMMV resistance improvement in watermelon and other Cucurbitaceae crops.

Citron watermelon genetic resources are useful for dessert watermelon breeding. The objective of the present study was to assess the genetic diversity present among citron watermelon landrace collections of South Africa using simple sequence repeat (SSR) markers. Thirty four diverse citron watermelon landraces were genotyped using 10 SSR markers. The markers amplified a total of 72 alleles from the sampled populations. Number of alleles ranged from 2 to 17 with a mean of 7.2 per locus. Number of effective alleles ranged from 1.03 to 6.74 with a mean of 3.54. The mean observed and expected heterozygosity were 0.48 and 0.60, respectively. The mean inbreeding coefficient was 0.18 suggesting high levels of heterozygosity among the collections. The mean polymorphic information content (PIC) of the SSR loci was 0.60 suggesting their value in genetic diversity analysis of watermelon. Analysis of molecular variance revealed highly significant difference ( P

Ethnopharmacological relevance Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao, was also known as watermelon belongs to family Cucurbitaceae, variously used as healthy food and in the treatment of liver and lungs problems. Currently, Citrullus lanatus has become a major economic crop of medicinal and edible effects with regional characteristics. Aim This study was designed to evaluate the hepatoprotective and antioxidant activity of the seed melon ( Citrullus lanatus ssp. vulgaris var. megalaspermus Lin et Chao) extract (SME) against carbon tetrachloride (CCl 4 ) induced hepatic fibrosis in mice. Materials and methods In this study, mice were randomly divided into 7 groups, including normal control, model, silymarin tablets as the positive control, SME 100, 200, 400, and 800 mg/kg. After 8 weeks, activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TG), hyaluronic acid (HA) and laminin (LN) were checked. The levels of antioxidant enzymes such as superoxide dismutase (SOD), glutataion (GSH) and glutathione peroxidase (GSH-Px) were determined after SME administration. The hydroxyproline (HYP) levels, malondialdehyde (MDA) levels and histopathologic examinations of hepatocyte fibrosis were also determined. Additionally, effects of SME on alpha-smooth muscle actin ( α -SMA) and transforming growth factor beta-1(TGF- β 1) protein expressions were determined. Results We found that SME could significantly lower the serum levels of hepatic enzyme markers AST, ALT, HA and LN ( P 0.01). Compared with the CCl 4 -only treatment group, levels of hepatic SOD and GSH-Px were significantly increased, and the MDA levels were remarkably decreased in mice treated by SME at medium dose (400 mg/kg) and high dose (800 mg/kg) ( P 0.01). A histological examination of the liver showed that lesions, including necrosis, lymphocyte infiltration and fatty degeneration, were partially healed by treatment with SME. The results of protein expressions studies displayed that SME could inhibit α -SMA and TGF- β 1 protein expression (P 0.01). Conclusion The present results suggested that protective effect of SME against CCl 4 -induced hepatic fibrosis may rely on its effect on reducing oxidative stress and improving drug metabolizing enzyme activity in liver.

Watermelon ( Citrullus lanatus (Thunb.) Matsum. & Nakai) is an important plant in the family Cucurbitaceae. Didymella bryoniae (Auersw.) Rehm [anamorph Phoma cucurbitacearum (Fr.) Sacc.] is the causative agent of gummy stem blight (GSB), a disease affecting members of the family Cucurbitaceae. Watermelon seedlings showing varied degree (20–90%) of suspected GSBs were collected from seedling companies in Antalya province, Turkey. The symptoms included angular water-soaked lesions, which turned tan over time; defoliation; dry, pale green stem; stem necrosis; gummy exudates; wilt; and the eventual death of the upper parts of the seedling plants. The growth of the fungal isolate in vitro showed white aerial and olivaceous mycelium, and olive to dark green or black substrate mycelium at the latter period of fungal growth. The colony surface was rough and undulated. The conidia were round-ended, cylindrical, monoseptate, and hyaline. The conidia ranged from 6.4 to 13.6 μm in length and 3.69–4.68 μm in diameter. The isolates were subjected to PCR using three primers, namely, DB-F3/DB-R3, GSBF1/GSBR1, and ITS1/ITS4, which produced fragment sizes of approximately 120, 780, and 560 bp, respectively. The real-time PCR using DB-F3/DB-R3 primer and SYBR Green fluorescence dye produced positive result for the samples tested. The D. bryoniae isolate was pathogenic to all the four different cucurbits tested and were consistently re-isolated from the diseased seedlings confirming their pathogenic status and thereby satisfying Koch's postulates. This is the second report confirming the presence of D. bryoniae in Turkey after its first detection in cucumber in 2015.

Tillage practices are critical for sustaining soil quality necessary for successful crop growth and productivity. A three-year study (2012–2014) was carried out to evaluate the influence of strip and conventional tillage practices and three water status levels [T1 = 100% of evapotranspiration (ET) demands, T2 = 0.75T1and T3 = 0.5T1] on plant morphology, physiology, yield and quality of triploid (seedless) watermelon (Citrullus lanatus cv. Magestic). Soil chemical and biological properties were also assessed at the end of the experimental study. Tillage practices (strip or ST and conventional or CT) started in 2009 and are being carried out to the present date of 2016. Irrigation was established using a center pivot system. Photosynthesis rate (Pn), stomatal conductance (gs), and chlorophyll content index (SPAD) were measured at flowering, fruit development and harvest stage and vine length measured at the harvest stage. Total marketable yield and fruit quality (firmness and sugar content) were determined during the harvest period. Soil chemical and microbial analysis were conducted at the end of the experimental period (March 2015). No significant differences (P = 0.05) were found between water deficit treatments in vine length, SPAD, Pn, gs, fruit firmness, and sugar content during the three-year study, except for vine length in 2013. But, marketable yield from T1 treatment was significantly higher (P = 0.03) than T3 in 2013. Vine length and SPAD measured from the ST plots were higher than CT, especially in 2012. Interestingly, marketable yield from ST was 8.6, 9.7 and 14.9 t ha−1 higher than CT in 2012, 2013 and 2014, respectively. Additionally, fruit sugar content under ST was statistically higher (P = 0.05) than those from CT. After 6 years of tillage practices (2009–2015) in the same site, ST increased total bacteria by 49%, active bacteria by 27%, active and total fungi by 37%, nematodes by 275%, and electrical conductivity by 14% compared to CT. However, ST significantly increased root-feeding nematodes (harmful to plant roots) and reduced phosphorus and nitrate-N compared to CT. Although long-term studies aimed at assessing soil quality and cumulative yield are required to further validate our results, yield and fruit quality (sugar content) responses were consistent across three years and with promising abundance of soil microbial activities.

Management of fusarium wilt caused by Fusarium oxysporum f. sp. niveum (Fon) (E.F. Sm.) W.C. Snyder & H.N. Han. in watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] is largely dependent on cultivation of resistant cultivars. Application of marker-assisted selection (MAS) in conventional breeding programs can accelerate the release of new watermelon cultivars resistant to fusarium wilt. Towards developing tools for MAS, physical (1024 SNPs) and genetic (389 SNPs) maps were developed in the current study for an F2 population (n = 89; Calhoun Gray x Sugar Baby) segregating for resistance against Fon race 1 using the genotyping by sequencing platform. A modified tray-dip method was established for high-throughput phenotyping of the segregating F3 population. A major quantitative trait locus (QTL) accounting for up to 38.4% of the phenotypic variation in the F3 population was identified on chromosome 1 on both the physical and genetic maps in a region previously associated with Fon race 1 resistance. This resistance locus was consistently detected over five different time points and three different phenotypic screens, showing the reliability of the screening method in discriminating susceptible and resistant genotypes. Eight resistance genes were found within the confidence interval of the identified QTL. SNPs close to this QTL may be exploited in MAS for fusarium wilt resistance in breeding programs. This study confirms the resistance locus on chromosome 1 and demonstrates the use of a physical map for QTL detection in watermelon. The SNPs reported here will be useful for future genetic studies in watermelon.