Evaluation of the effect of Carica papaya seed on the growth performance of fattening rabbits.

Successful breeding depends on feeding. The present study aims to evaluate the Carica papaya seed effect on the growth performance of rabbits. The zootechnical parameters studied are weight growth, average daily gain, Feed Conversion Ratio, and carcass characteristics of kits. The experiment was conducted on 48 rabbits, divided into 4 groups, for 6 weeks. Forty-eight rabbits were divided into four (04) groups of 3 repetitions of 4 rabbits. The animals were fed diets containing various levels of papaya seed powder at variable contents: 0% (group T0), 4% (group T1), 6% (group T2), and 8% (group T3). At the end of the experiment, three animals were slaughtered in each animal group to assess the quality of the carcasses and organs. 6% of the seeds of Carica papaya significantly improved (p < 0.05) the average daily gain of the kits: T2 (22.40 g / d) compared to the T0 group (11.32 g / d), T1 (12.20 g / d) and T3 (17.53 g / d). The best Feed Conversion Ratio (0.80) was recorded in the animals of group T2. In contrast, the highest carcass yield was recorded in the rabbits of group T3 (62.70%). In conclusion, 6% was optimal in the feed rations of fattened rabbits to improve production performance. Breeders can consider the benefits of introducing Carica papaya seeds into the rabbits' diet.

In silico identification of papaya genome-encoded microRNAs to target begomovirus genes in papaya leaf curl disease.

Papaya leaf curl disease (PaLCuD) is widespread and classified in the genus begomovirus (Geminiviridae), disseminated by the vector whitefly Bemisia tabaci. RNA interference (RNAi)-based antiviral innate immunity stands as a pivotal defense mechanism and biological process in limiting viral genomes to manage plant diseases. The current study aims to identify and analyze Carica Papaya locus-derived capa-microRNAs with predicted potential for targeting divergent begomovirus species-encoded mRNAs using a 'four integrative in silico algorithms' approach. This research aims to experimentally activate the RNAi catalytic pathway using in silico-predicted endogenous capa-miRNAs and create papaya varieties capable of assessing potential resistance against begomovirus species and monitoring antiviral capabilities. This study identified 48 predicted papaya locus-derived candidates from 23 miRNA families, which were further investigated for targeting begomovirus genes. Premised all the four algorithms combined, capa-miR5021 was the most anticipated miRNA followed by capa-miR482, capa-miR5658, capa-miR530b, capa-miR3441.2, and capa-miR414 'effective' papaya locus-derived candidate capa-miRNA and respected putative binding sites for targets at the consensus nucleotide position. It was predicted to bind and target mostly to AC1 gene of the complementary strand and the AV1 gene of the virion strand of different begomovirus isolates, which were associated with replication-associated protein and encapsidation, respectively, during PaLCuD. These miRNAs were also found targeting betaC1 gene of betasatellite which were associated with retardation in leaf growth and developmental abnormalities with severe symptoms during begomovirus infection. To validate target prediction accuracy, we created an integrated Circos plot for comprehensive visualization of host-virus interaction. In silico-predicted papaya genome-wide miRNA-mediated begomovirus target gene regulatory network corroborated interactions that permit in vivo analysis, which could provide biological material and valuable evidence, leading to the development of begomovirus-resistant papaya plants. The integrative nature of our research positions it at the forefront of efforts to ensure the sustainable cultivation of papaya, particularly in the face of evolving pathogenic threats. As we move forward, the knowledge gained from this study provides a solid foundation for continued exploration and innovation in the field of papaya virology, and to the best of our knowledge, this study represents a groundbreaking endeavor, undertaken for the first time in the context of PaLCuD research.

Anthelmintic screening of Bangladeshi medicinal plants and related phytochemicals using in vitro and in silico methods: An ethnobotanical perspective.

ETHNOPHARMACOLOGICAL RELEVANCE: Infections caused by parasitic worms or helminth continue to pose a great burden on human and animal health, particularly in underdeveloped tropical and subtropical countries where they are endemic. Current anthelmintic drugs present serious limitations and the emergence of drug resistance has made it increasingly challenging to combat such infections (helminthiases). In Bangladesh, medicinal plants are often used by indigenous communities for the treatment of helminthiases. Knowledge on such plants along with screening for their anthelmintic activity has the potential to lead to the discovery of phytochemicals that could serve as novel molecular scaffolds for the development of new anthelminthic drugs. AIM OF THE STUDY: The purpose of this study was i) to conduct an ethnobotanical survey to gather data on Bangladeshi medicinal plants used in the treatment of helminthiases, ii) to test plants with the highest use values for their in vitro anthelmintic activity, and iii) to carry out in silico screening on phytochemicals present in the most active plant extract to investigate their ability to disrupt ß-tubulin function in helminths. METHODS: The ethnobotanical survey was conducted across three sub-districts of Bangladesh, namely Mathbaria, Phultala and Khan Jahan Ali. The in vitro screening for anthelmintic activity was performed in a motility test using adult Haemonchus contortus worms. Virtual screening using PyRx was performed on the phytochemicals reported from the most active plant, exploring their interactions with the colchicine binding site of the ß-tubulin protein target (PDB ID: 1SA0). RESULTS: The survey respondents reported a total of 32 plants for treating helminthiases. Based on their use values, the most popular choices were Ananas comosus (L.) Merr., Azadirachta indica A.Juss., Carica papaya L., Citrus maxima (Burm.) Merr., Curcuma longa L., Momordica charantia L., Nigella sativa L. and Syzygium cumini (L.) Skeels. In vitro anthelmintic testing revealed that A. indica leaves and bark had the highest activity with LC50 values of 16 mg/mL in both cases. Other plant extracts also exhibited good anthelmintic activity with LC50 values ranging from 16 to 52 mg/mL, while the value for albendazole (positive control) was 8.39 mg/mL. The limonoids nimbolide and 28-deoxonimbolide showed a binding affinity of -8.9 kcal/mol, and satisfied all drug-likeness parameters. The control ligand N-deacetyl-N-(2-mercaptoacetyl)colchicine had a binding affinity of -6.9 kcal/mol. CONCLUSION: Further in silico and in vitro studies are warranted on the identified limonoids to confirm the potential of these derivatives as novel drug templates for helminthiases. The current study supports the need for an ethnobotanical survey-based approach to discover novel drug templates for helminthiases.

Transcriptome, Plant Hormone, and Metabolome Analysis Reveals the Mechanism of Purple Pericarp Formation in 'Zihui' Papaya (Carica papaya L.).

The color of the pericarp is a crucial characteristic that influences the marketability of papaya fruit. Prior to ripening, normal papaya exhibits a green pericarp, whereas the cultivar 'Zihui' displays purple ring spots on the fruit tip, which significantly affects the fruit's visual appeal. To understand the mechanism behind the formation of purple pericarp, this study performed a thorough examination of the transcriptome, plant hormone, and metabolome. Based on the UPLC-ESI-MS/MS system, a total of 35 anthocyanins and 11 plant hormones were identified, with 27 anthocyanins and two plant hormones exhibiting higher levels of abundance in the purple pericarp. In the purple pericarp, 14 anthocyanin synthesis genes were up-regulated, including CHS, CHI, F3H, F3'5'H, F3'H, ANS, OMT, and CYP73A. Additionally, through co-expression network analysis, three MYBs were identified as potential key regulators of anthocyanin synthesis by controlling genes encoding anthocyanin biosynthesis. As a result, we have identified numerous key genes involved in anthocyanin synthesis and developed new insights into how the purple pericarp of papaya is formed.

Safety of Oral Carica papaya L. Leaf 10% Ethanolic Extract for Acute and Chronic Toxicity Tests in Sprague Dawley Rats.

Carica papaya L. leaves, traditionally utilized in dietary supplements and pharmaceuticals, exhibit a broad spectrum of potentially therapeutic properties, including anti-inflammatory, antimalarial, and wound healing properties. This study examined the acute and chronic toxicity of 10% ethanolic-extracted C. papaya leaf in Sprague Dawley rats. The acute toxicity assessment was a single oral dose of 5000 mg/kg body weight, while the chronic toxicity assessment included daily oral doses of 100, 400, 1000, and 5000 mg/kg over 180 days. Systematic monitoring covered a range of physiological and behavioral parameters, including body and organ weights. End-point evaluations encompassed hematological and biochemical analyses, along with gross and histopathological examinations of internal organs. Findings revealed no acute toxicity in the C. papaya leaf extract group, although a significant decrease in uterine weight was observed without accompanying histopathology abnormalities. In the chronic toxicity assessment, no statistically significant differences between the control and the C. papaya leaf extract groups were detected across multiple measures, including behavioral, physiological, and hematological indices. Importantly, histopathological examination corroborated the absence of any tissue abnormalities. The study results indicate that C. papaya leaf extract exhibited no adverse effects on the rats during the 180-day oral administration period, affirming its potential safety for prolonged usage.

Effect of cinnamon essential oil/γ-cyclodextrin inclusion complex on papaya quality and shelf-life.

BACKGROUND: Papaya, a highly nutritious and economically significant fruit, is susceptible to infections caused by phytopathogenic fungi. Cinnamon essential oil, derived from Cinnamomum cassia (CC), shows promise in preserving papaya due to its antifungal properties. However, CC is volatile, sensitive to environmental factors, and carries a strong aroma. γ-Cyclodextrin (γ-CD) is known for encapsulating hydrophilic molecules, shielding them from environmental influences, reducing odor, and enabling controlled release due to its unique channel structure. This study aimed to tackle these challenges by preparing and characterizing an inclusion complex of CC with γ-CD (CC-γ-CD), and subsequently evaluating its efficacy in preserving papaya fruits. RESULTS: Analyses, including Fourier-infrared, powder X-ray diffraction, thermal gravity analysis, differential scanning calorimeter, and scanning electron microscopy, revealed successful encapsulation of CC components within the γ-CD cavity. Evaluations of the CC-γ-CD complex's impact on papaya fruit shelf life and quality showed notable enhancements. Fruits treated with CC-γ-CD inclusion complex at a dose of 10 g kg-1 exhibited a 55% extension in shelf-life, evidenced by reduced disease severity index compared with untreated fruit in the same storage conditions. Detailed physicochemical and bromatological assessments highlighted significant improvements, particularly in fruit treated with CC-γ-CD inclusion complex at a dose of 10 g kg-1 . CONCLUSION: The application of CC-γ-CD inclusion complex at 10 g kg-1 extended the shelf-life of papaya fruit, significantly and markedly improved the overall quality. These findings underscore the potential of the CC-γ-CD inclusion complex as an effective preservative for papaya, offering a promising solution for its postharvest management and marketability. © 2024 Society of Chemical Industry.

Effects of Carica papaya peel meal-based diets on rabbit bucks' spermiogram and reaction time.

The study aimed to evaluate the effects of Carica papaya peel meal-based diet on spermiogram and reaction time in rabbit bucks. Ripe pawpaw fruits were harvested during the dry season. The peels were carefully removed from the pulp and sun-dried for a week. Afterward, they were ground and included in the test diets as pawpaw peel meal (PPM) at inclusion rates of 0%, 15%, and 30%. Rabbit bucks (n = 15) were randomly separated into three groups of five bucks and labeled as groups A, B, and C. Group A, the control group (0%), was fed the basal protein diet (BD), group B (PPM 15) was given a PPM-based diet (15%), while C (PPM 30) was given diet composed of PPM (30%). Semen samples were collected and evaluated fortnightly for 14 weeks. The reaction time and mean ejaculate volume were lower (P < 0.05) in the treatment groups than in the control. Sperm motility and concentration decreased significantly (P < 0.05) across the groups from week 4 to the end of the experiment. Bucks fed PPM 15%, and PPM 30% had significantly (P < 0.05) higher percentages of dead sperm cells and total spermatozoa abnormalities. The control had (86%) normal spermatozoa morphology while those of PPM 15% and PPM 30% were (61%) and (52%), respectively. PPM 30% had the highest abnormal spermatozoa (47%) compared to PPM 15% (38%) and control (13%). The findings indicate that pawpaw peels up to 15% and 30% in the diet have a negative effect on spermiogram.

Evaluation of supplemented protein-L-isoaspartate-O-methyltransferase (PIMT) gene of Carica papaya and Ricinus communis in stress survival of Escherichia coli BL21(DE3) cells.

In growing plant population, effect of stress is a perturb issue affecting its physiological, biochemical, yield loss and developmental growth. Protein-L-isoaspartate-O-methyltransferase (PIMT) is a broadly distributed protein repair enzyme which actuate under stressful environment or aging. Stress can mediate damage converting protein bound aspartate (Asp) residues to isoaspartate (iso-Asp). This spontaneous and deleterious conversion occurs at an elevated state of stress and aging. Iso-Asp formation is associated with protein inactivation and compromised cellular survival. PIMT can convert iso-Asp back to Asp, thus repairing and contributing to cellular survival. The present work describes the isolation, cloning, sequencing and expression of PIMT genes of Carica papaya (Cp pimt) and Ricinus communis (Rc pimt) Using gene specific primers, both the pimts were amplified from their respective cDNAs and subsequently cloned in prokaryotic expression vector pProEXHTa. BL21(DE3) strain of E. coli cells were used as expression host. The expression kinetics of both the PIMTs were studied with various concentrations of IPTG and at different time points. Finally, the PIMT supplemented BL21(DE3) cells were evaluated against different stresses in comparison to their counterparts with the empty vector control.

Fabrication, organoleptic evaluation and in vitro characterization of cream loaded with Carica papaya seed extract.

OBJECTIVE: The current study aimed to provide preliminary insights into potential biopharmaceutical applications of Carica papaya seed extract by evaluating its phytochemical and biological profiles. Furthermore, the study aimed to develop a stable oil-in-water (O/W) emulsion for the effective delivery of antioxidant-rich biologicals for cosmetic purposes. METHODS: The hydroethanolic (ethanol 80%: 20% water) extract of C. papaya seeds was prepared via maceration technique. The chemical composition was carried out through preliminary phytochemical screening and estimation of total phenolic contents (TPC) and total flavonoid contents (TFC). The biological profile of the extract was explored using various in-vitro antioxidant methods. The homogenization procedure was used to create a cream of O/W and various tests were applied to assess the stability of the emulsion. By keeping the emulsion at different storage conditions (8 ± 0.5°C, 25 ± 0.5°C, 40 ± 0.5°C, and 40 ± 0.5°C ± 75% relative humidity [RH]) for a period of 28 days), the physical stability parameters of the emulsion, including pH, viscosity, centrifugation, phase separation, and conductivity, as well as rheological parameters and organoleptic parameters (odor, color, liquefaction, and creaming), were assessed. RESULTS: The preliminary phytochemical screening assay revealed the presence of various plant secondary metabolites including alkaloids, phenolics, flavonoids, tannins, saponins, and quinones. The extract was found to be rich in TPC and TFC. The in vitro antioxidant study gave maximum activity in the DPPH method. The plant extract containing cosmetic cream exhibited remarkable stability during the entire research. Data gathered indicated that no phase separation or liquefaction was seen after the experimental period. Throughout the experimental period, a small variation in the pH and conductivity values of the base and formulation was seen. CONCLUSION: The findings suggest that the seed extract of C. papaya is a rich source of polyphenols with antioxidant potential and can be a promising alternative for the treatment of various ailments. The stability of emulsion paves the way for its utilization as a carrier for the delivery of 3% C. papaya seed extract and applications in cosmetics products.

Phytochemical Extract from Carica papaya Leaves and Punica granatum Seeds as Therapy Against Cognitive Impairment in a Murine Model.

Mild cognitive impairment (MCI) is defined as inter-stage between normal cognitive aging and major neurocognitive disorder (MND). This state of decay is a crucial factor in treatment to prevent the progression to MND. In this study, our group developed a virtual screening process to evaluate 2568 phytochemical compounds against 5 key proteins associated with MCI and MND. As a result, two potential candidates were identified: carpaine, found in Carica papaya leaves, and punicalagin, present in Punica granatum. A model of cognitive impairment (CI) was developed in 10-month-old male Sprague Dawley rats by administering aluminum chloride (AlCl3) at a dose of 100 mg/kg/day for 30 days. After AlCl3 administration period, one of the groups received carpaine and punicalagin in a phytochemical extract (PE) by oral gavage for 30 days. Novel object recognition test (NOR) was assessed at three different time points (T1 - before CI, T2 - after CI, and T3 - after PE treatment). Glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) were identified in the hippocampus of rats at the end of the study period. After administration of AlCl3, a reduction in discrimination index vs control rats (CI = 0.012 ± 0.08 vs Control = 0.076 ± 0.03), was observed. After phytochemical extract treatment, a significant increase in discrimination index values was observed in the PE group 0.4643 ± 0.13 vs CI group 0.012 ± 0.08. Additionally, the evaluation of immunohistochemistry showed an increase in GFAP positivity in the hippocampus of the CI groups, while a slight decrease was observed in the PE group. This work addressed a comprehensive methodology that utilized in silico tools to identify phytochemical compounds (carpaine and punicalagin) as potential candidates for affecting key proteins in CI. The phytochemical extract containing carpaine and punicalagin resulted in a trend in the decrease of GFAP expression in the hippocampus and improved recognition memory in rats with CI induced by age and AlCl3 administration.

Antioxidant activity of Carica papaya & Persea americana fruits against cadmium induced neurotoxicity, nephrotoxicity, and hepatotoxicity in rats with a computational approach.

BACKGROUND: Cadmium is widely reported to interfere with the proper functioning of cells by disrupting cellular redox balance, causing apoptosis, and leading to hepatocellular damage, neurotoxicity, pulmonary edema, cancer, and cardiac and neurodegenerative diseases. Treatment of Cd toxicity with drugs brings undesirable side effects, making it necessary to remove Cd from the body safely without harmful effects. OBJECTIVE: This study aimed to determine how Cd causing malfunctioning of cells could be treated with antioxidant-rich avocado and papaya fruit juices. This work fixated on elucidating and comparing the effects of avocado and papaya fruit juice on Cd-dependent impairment in memory and spatial learning. In addition, various markers of tissue damage, such as the concentration of biomarkers in liver and kidney tissue, the expression of antioxidant enzymes and Cd-induced lipid peroxidation, were analyzed. METHODOLOGY: in silico studies of the phytochemical constituents of avocado and papaya (ligands) were docked against antioxidant enzymes Catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) as macromolecules showed strong hydrogen binding with significant binding capacities. To develop the Cd in vivo model, rats were administered CdCl2 (200 ppm) in drinking water for 7 weeks. After induction of Cd toxicity, rats were post-treated with avocado and papaya (10% w/v each) in a standard diet. After post-treatment, memory and learning were assessed using the Morris water maze behavioural test. Biochemical tests for liver and kidney biomarkers were monitored. To determine the level of ROS, lipid peroxidation was determined by Malondialdehyde (MDA) assay. Gene expression of SOD, CAT and GPx were determined via qRT-PCR. RESULTS: This study demonstrated that Cd accumulation in the liver, kidney and hippocampal tissues was reduced after treatment with avocado and papaya. SOD, CAT and GPX gene expression were upregulated after avocado and papaya juice treatment. Moreover, a comparative analysis between avocado and papaya fruit juices clarified that papaya has more active potential for improving memory and learning, upregulating the expression of antioxidant enzymes, and reducing lipid peroxidation in the liver, kidney, and hippocampus. CONCLUSION: This study suggests that a diet containing papaya and avocado can help treat the lethal effects caused by Cd. Because their active constituents can improve health at the cellular and molecular levels.

First report of anthracnose fruit rot of papaya caused by Colletotrichum gigasporum in China.

Papaya (Carica papaya L.) belonging to the family Caricaceae is well known for its economic and nutritional value. Anthraconse caused by Colletotrichum spp. is a main postharvest disease of papaya fruit during storage (Cia et al., 2007). In July 2022, papaya fruits with anthracnose symptoms were collected in Changjiang County (108.996180E, 19.246560N), Hainan Province, China. The disease incidence of fruit rot reached 6.3%. Initial symptoms appeared as the watery lesions with tiny black spots, turning to dark brown, sunken necrotic lesions. The diseased tissues were cut into 18 pieces (5×5 mm) from 6 papaya fruits, disinfected with 2% sodium hypochlorite for 60 s, and rinsed three times with sterilized water. The pieces were air-dried and then placed on potato dextrose agar (PDA) at 28 ℃ for five days. Twelve isolates with similar morphology were obtained from 18 tissue pieces. Three isolates (FMG01, FMG02 and FMG03) were selected for morphological identification, molecular identification, and pathogenicity tests. Colonies were initially white, then gradually became dark grey on PDA. The ascospores were hyaline, fusoid, rounded at both ends, 37.43-84.32 (55.79±7.61) µm × 4.30-6.55 (5.36±0.60) µm (n=50). The conidia were hyaline, unicellular, long cylindrical, bluntly rounded at both ends, 11.59-25.54 (18.62±2.33) µm × 5.12-8.44 (7.19±0.62) µm (n=100). Appressoria were gray to dark brown, irregular, pyriform, or ovoid, 10.14-21.40 (13.81±2.25) µm × 6.05-11.85 (9.16±1.29) µm (n=50). Morphological features are similar to Colletotrichum gigasporum identified and described by Rakotoniriana et al (Rakotoniriana et al., 2013). In order to accurately identify the isolates, the internal transcribed spacer region (ITS) of the rDNA, the glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the partial actin (ACT), the beta-tubulin (TUB2) and the calmodulin (CAL) genes were amplified and sequenced (Cannon et al., 2012). The nucleotide sequences were deposited into GenBank (accession numbers, ITS: OR017446 to OR017448, GAPDH: OR042810 to OR042812, ACT: OR042813 to OR042815, TUB2: OR042816 to OR042818, CAL: OR042819 to OR042821). Based on the BLASTn analysis, these sequences were more than 99% with the reference strain CBS 125476 of C. gigasporum sequences (ITS: MH863698, GAPDH: KF687833, ACT: KF687790, TUB2: KF687875, CAL: KF687814), respectively. The results of the multilocal phylogenetic analysis showed that the three isolates were C. gigasporum based on the Maximum Likelihood and Bayesian inference method. The pathogenicity test was performed by wounded with a sterile needle on the surface-sterilized papaya fruits. The mycelial discs (5 mm diameter) of three isolates were inoculated orderly on the same fruit, and the same inoculation was applied to non-wound papaya fruits. The control group were inoculated with sterilized PDA. Each treatment carried out with 9 fruits. The inoculated fruits were placed at 28 ℃ in plastic preservation boxes (32×22×11 cm) with sterilized distilled water to maintain high humidity. After 5 d of inoculation, typical anthracnose symptoms were observed on wound fruits and the non-wound fruits developed symptoms at 7 dpi, control fruits were symptomless. The fungi re-isolated from the inoculated fruits lesions after inoculation and identified by morphological characterization and molecular identification, fulfilling Koch's postulates. C. gigasporum has been reported causing leaf rot of Dalbergia odorifera in China (Wan et al., 2018). To our knowledge, this is the first report of anthracnose fruit rot of papaya caused by C. gigasporum in China.

The synthesis of papaya fruit flavor-related linalool was regulated by CpTPS18 and CpNAC56.

Papaya is a tropical fruit crop renowned for its rich nutrition, particularly pro-vitamin A. Aroma substances are a major component of fruit quality. While extensive research has been conducted on papaya aroma, there has been a notable lack of in-depth research into a specific class of substances. To bridge this gap, our study focused on analyzing the aroma components of various papaya varieties and their biosynthesis pathways. We compared the volatile components of three papaya varieties with distinct flavors at various ripeness stages. A continuous accumulation of linalool, a volatile compound, in the 'AU9' fruit was detected as it matured. The linalool content reached 56% of the total volatile components upon full ripening. Notably, this percentage was significantly higher than that observed in the other two varieties, 'ZhongBai' and 'Malaysian 7', indicating that linalool serves as the primary component influencing the papaya's odor. Subsequently, we identified CpTPS18, a gene associated with linalool biosynthesis, and demonstrated its ability to catalyze linalool production from GPP and enhance its accumulation through overexpression in papaya fruits, both in vivo and in vitro. Based on transcriptomic analysis, it was predicted that CpMYB56 and CpNAC56 may transcriptionally activate the expression of CpTPS18. Subsequent yeast one-hybrid assay and dual luciferase analysis revealed that CpNAC56 activates the transcription of CpTPS18. Transient overexpression in vivo demonstrated that this gene could upregulate the expression of CpTPS18 and promote linalool accumulation. These results uncovered the primary volatile molecule responsible for papaya fruit odor and identified two major genes influencing its biosynthesis. The genomic resources and information obtained from this study will expedite papaya improvement for fruit quality.

Time-Dependent Proteomic Signatures Associated with Embryogenic Callus Induction in Carica papaya L.

Sex segregation increases the cost of Carica papaya production through seed-based propagation. Therefore, in vitro techniques are an attractive option for clonal propagation, especially of hermaphroditic plants. Here, we performed a temporal analysis of the proteome of C. papaya calli aiming to identify the key players involved in embryogenic callus formation. Mature zygotic embryos used as explants were treated with 20 µM 2,4-dichlorophenoxyacetic acid to induce embryogenic callus. Total proteins were extracted from explants at 0 (zygotic embryo) and after 7, 14, and 21 days of induction. A total of 1407 proteins were identified using a bottom-up proteomic approach. The clustering analysis revealed four distinct patterns of protein accumulation throughout callus induction. Proteins related to seed maturation and storage are abundant in the explant before induction, decreasing as callus formation progresses. Carbohydrate and amino acid metabolisms, aerobic respiration, and protein catabolic processes were enriched throughout days of callus induction. Protein kinases associated with auxin responses, such as SKP1-like proteins 1B, accumulated in response to callus induction. Additionally, regulatory proteins, including histone deacetylase (HD2C) and argonaute 1 (AGO1), were more abundant at 7 days, suggesting their role in the acquisition of embryogenic competence. Predicted protein-protein networks revealed the regulatory role of proteins 14-3-3 accumulated during callus induction and the association of proteins involved in oxidative phosphorylation and hormone response. Our findings emphasize the modulation of the proteome during embryogenic callus initiation and identify regulatory proteins that might be involved in the activation of this process.

Rutin extraction from female Carica papaya Linn. using ultrasound and microwave-assisted extractive methods: Optimization and extraction efficiencies.

Green extractive methods accompanied by resource conservation through process optimization are important in working towards sustainable processes. In the present paper, rutin was extracted from the leaf of female Carica papaya Linn using microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), sequential microwave ultrasound-assisted extraction (MUAE), and sequential ultrasound microwave-assisted extraction (UMAE) methods. Subsequently, the effect of extraction parameters on rutin yield were analyzed and compared. In addition, the extraction efficiency and energy consumption of the extraction processes were measured and discussed. In the present study, solid-liquid (S/L) ratio was determined to be the most significant extraction variable. Under optimized conditions, MUAE and UMAE were determined to yield the highest amount of rutin extracted at 18.46 ± 0.64 mg/g and 18.43 ± 0.81 mg/g, respectively. However, MUAE was determined to be the least resource efficient method as it consumed the highest amount of energy due to its relatively long extraction time. UAE was determined to be the most efficient in resource utilization as it required the least amount of energy for every mg/g of yield extracted, while the yield obtained was, nonetheless, comparatively high. The optimal condition obtained for UAE was 20 min of ultrasonic extraction time (TU), 20 % of ethanol mixture concentration (C), 710 µm of particle size (S), and 1:650 wt/wt of solid-liquid (S/L) ratio (R).

Genomic and Transcriptomic Insights into the Evolution and Divergence of MIKC-Type MADS-Box Genes in Carica papaya.

MIKC-type MADS-box genes, also known as type II genes, play a crucial role in regulating the formation of floral organs and reproductive development in plants. However, the genome-wide identification and characterization of type II genes as well as a transcriptomic survey of their potential roles in Carica papaya remain unresolved. Here, we identified and characterized 24 type II genes in the C. papaya genome, and investigated their evolutional scenario and potential roles with a widespread expression profile. The type II genes were divided into thirteen subclades, and gene loss events likely occurred in papaya, as evidenced by the contracted member size of most subclades. Gene duplication mainly contributed to MIKC-type gene formation in papaya, and the duplicated gene pairs displayed prevalent expression divergence, implying the evolutionary significance of gene duplication in shaping the diversity of type II genes in papaya. A large-scale transcriptome analysis of 152 samples indicated that different subclasses of these genes showed distinct expression patterns in various tissues, biotic stress response, and abiotic stress response, reflecting their divergent functions. The hub-network of male and female flowers and qRT-PCR suggested that TT16-3 and AGL8 participated in male flower development and seed germination. Overall, this study provides valuable insights into the evolution and functions of MIKC-type genes in C. papaya.

Antimicrobial activity of phytofabricated silver nanoparticles using Carica papaya L. against Gram-negative bacteria.

Background and Aim: Antibiotic resistance, especially in Gram-negative bacteria, is a major public health risk affecting all industries requiring the use of antibiotics, including agriculture and animal breeding. This study aimed to use papaya extracts to synthesize silver nanoparticles (AgNPs) and evaluate their antimicrobial activity against various Gram-negative bacteria. Materials and Methods: Silver nanoparticles were synthesized from the aqueous extracts of papaya seed, root, and bark, with AgNO3 used as a reducing agent. The phytofabricated AgNPs were analyzed by ultraviolet-visible absorbance, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy, and photon cross-correlation spectroscopy (PCCS). The disc-diffusion method was used to perform antibacterial analysis, and the minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations were determined. We also investigated the antibiofilm activity of AgNPs and attempted to elucidate the potential mechanism of action on Escherichia coli ATCC 25922. Results: Phytofabrication of AgNPs was successful with papaya root (PR-AgNPs) and papaya seed (PS-AgNPs), but not with papaya bark. Silver nanoparticles using papaya root and PS-AgNPs were both cubic and showed maximum absorbances of 2.6 and 0.3 AUs at 411.6 and 416.8 nm wavelengths and average hydrodynamic diameters X50 of 59.46 ± 7.03 and 66.57 ± 8.89 nm, respectively. The Ag in both AgNPs was confirmed by X-ray fluorescence by a distinctive peak in the spectrum at the silver Kα line of 22.105 keV. Both AgNPs exhibited broad-spectrum antimicrobial and antibiofilm activity against all Gram-negative bacteria, and PR-AgNPs were slightly better than AgNPs-PS. The MIC ranged from 16 µg/mL-128 µg/mL and 16 µg/mL-64 µg/mL, respectively, for PS-AgNPs and PR-AgNPs. The elucidation of the mechanism of action revealed interference with E. coli ATCC 25922 growth kinetics and inhibition of H+-ATPase proton pumps. Conclusion: Papaya seed and root extracts were efficient reducing agents for the biogenic synthesis of AgNPs, with noteworthy antibacterial and antibiofilm activities. Future studies should be conducted to identify the phytochemicals and the mechanism involved in AgNPs synthesis.

Anti-Inflammatory and Anti-Oxidative Effects of Polysaccharides Extracted from Unripe Carica papaya L. Fruit.

This study evaluated the antioxidative and anti-inflammatory activities of polysaccharides extracted from unripe Carica papaya L. (papaya) fruit. Three papaya polysaccharide (PP) fractions, namely PP-1, PP-2, and PP-3, with molecular weights of 2252, 2448, and 3741 kDa, containing abundant xylose, galacturonic acid, and mannose constituents, respectively, were obtained using diethylaminoethyl-Sepharose™ anion exchange chromatography. The antioxidant capacity of the PPs, hydroxyl radical scavenging assay, ferrous ion-chelating assay, and reducing power assay revealed that the PP-3 fraction had the highest antioxidant activity, with an EC50 (the concentration for 50% of the maximal effect) of 0.96 mg/mL, EC50 of 0.10 mg/mL, and Abs700 nm of 1.581 for the hydroxyl radical scavenging assay, ferrous ion-chelating assay, and reducing power assay, respectively. In addition, PP-3 significantly decreased reactive oxygen species production by 45.3%, NF-κB activation by 32.0%, and tumor necrosis factor-alpha and interleukin-6 generation by 33.5% and 34.4%, respectively, in H2O2-induced human epidermal keratinocytes. PP-3 exerts potent antioxidative and anti-inflammatory effects; thus, it is a potential biofunctional ingredient in the cosmetic industry.

Genome-Wide Analysis of WRKY and NAC Transcription Factors in Carica papaya L. and Their Possible Role in the Loss of Drought Tolerance by Recent Cultivars through the Domestication of Their Wild Ancestors.

A genome-wide analysis for two families of key transcription factors (TF; WRKY and NAC) involved in drought response revealed 46 WRKY and 66 NAC members of the Carica papaya genome. A phylogenetic analysis grouped the CpWRKY proteins into three groups (I, II a, b, c, d, e and III), while the CpNAC proteins were clustered into 15 groups. The conserved domains, chromosomal localization and promoter cis-acting elements were also analyzed. In addition, from a previous transcriptome study of two contrasting genotypes in response to 14 days of water deficit stress (WDS), we found that 29 of the 46 CpWRKYs genes and 25 of the 66 CpNACs genes were differentially expressed in response to the WDS. In the present paper, the native wild genotype (WG) (collected in its center of origin) consistently showed a higher expression (transcripts per million; TPM and fold change; FC) than the commercial genotype (CG) in almost all the members of the CpWRKY and CpNAC gene families. To corroborate this, we selected CpWRKY50 and CpNAC83.1 for further evaluation by RT-qPCR. Consistently, the WG showed higher relative expression levels (REL) after 14 days of WDS than the CG, in both the leaves and roots. The results suggest that the CpWRKY and CpNAC TF families are important for drought tolerance in this species. The results may also suggest that, during the domestication process, the ability of the native (wild) C. papaya genotypes to respond to drought (including the overexpression of the CpWRKY and CpNAC genes) was somehow reduced in the current commercial genotypes.

In-silico screening and identification of potential drug-like compounds for dengue-associated thrombocytopenia from Carica papaya leaf extracts.

Dengue virus is a mosquito-borne pathogen that causes a variety of illnesses ranging from mild fever to severe and fatal dengue haemorrhagic fever or dengue shock syndrome. One of the major clinical manifestations of severe dengue infection is thrombocytopenia. The dengue non-structural protein 1 (NS1) is the primary protein that stimulates immune cells via toll-like receptor 4 (TLR4), induces platelets, and promotes aggregation, which could result in thrombocytopenia. The leaf extracts of Carica papaya seem to have therapeutic benefits in managing thrombocytopenia associated with dengue. The present study focuses on understanding the underlying mechanism of the use of papaya leaf extracts in treating thrombocytopenia. We have identified 124 phytocompounds that are present in the papaya leaf extract. The pharmacokinetics, molecular docking, binding free energy calculations, and molecular dynamic simulations were performed to investigate the drug-like properties, binding affinities, and interaction of phytocompounds with NS1 protein as well as the interactions of NS1 with TLR4. Three phytocompounds were found to bind with the ASN130, a crucial amino acid residue in the active site of the NS1 protein. Thus, we conclude that Rutin, Myricetin 3-rhamnoside, or Kaempferol 3-(2''-rhamnosylrutinoside) may serve as promising molecules by ameliorating thrombocytopenia in dengue-infected patients by interfering the interaction of NS1 with TLR4. These molecules can serve as drugs in the management of dengue-associated thrombocytopenia after verifying their effectiveness and assessing the drug potency, through additional in-vitro assays.Communicated by Ramaswamy H. Sarma.