Citrus fruits are subjected to a diversity of postharvest diseases caused by various pathogens during picking, packing, storage and transportation. Green and blue molds, caused by Penicillium digitatum and Penicillium italicum, respectively, are two major postharvest citrus diseases and cause significant economic losses during the commercialization phase. Currently, the control of postharvest citrus diseases relies mainly on the use of synthetic fungicides, which usually result in the resistance against fungal attack, environment pollution and health hazards. In recent years, much attention has been given to the preservation of citrus by naturally isolated edible plant extracts, medicinal plant extracts, Citrus extracts and volatiles, et al. Scientists worldwide devote their time and energy to discover the high effect, low toxicity, safety and inexpensive plant-derived fungicides. The current review will highlight plant-derived fungicides and chemical constituents that aim to inhibit P. digitatum and P. italicum in vitro and in vivo. Coatings enriched with plant extracts could be good alternative methods for Citrus fruits preservation. Problems and prospects of the research and development of plant-derived natural fungicides will also be discussed in this article.

Methylglyoxal, a reactive dicarbonyl compound, is mainly formed from glycolysis. Methylglyoxal can lead to the dysfunction of mitochondria, the depletion of cellular anti-oxidation enzymes and the formation of advanced glycation ends. Previous studies showed that the accumulation of methylglyoxal and advanced glycation ends can impair the oocyte maturation and reduce the oocyte quality in aged and diabetic females. In this study, we showed that resveratrol, a kind of phytoalexin found in the skin of grapes, red wine and other botanical extracts, can alleviate the adverse effects caused by methylglyoxal, such as inhibition of oocyte maturation and disruption of spindle assembly. Besides, methylglyoxal-treated oocytes displayed more DNA double strands breaks and this can also be decreased by treatment of resveratrol. Further investigation of these processes revealed that methylglyoxal may affect the oocyte quality by resulting in excessive reactive oxygen species production, aberrant mitochondrial distribution and high level lipid peroxidation, and resveratrol can block these cytotoxic changes. Collectively, our results showed that resveratrol can protect the oocytes from methylglyoxal-induced cytotoxicity and this was mainly through the correction of the abnormity of cellular reactive oxygen species metabolism.

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Carvacrol (5-Isopropyl-2-methylphenol), a volatile oil constituent, mainly exists in Labiaceae family plants. Carvacrol has long been studied for its natural antifungal potential and food preservative potential. However, its exact mode of action, especially against Penicillium digitatum (P. digitatum), remains unexplored. Herein, a 1 H-NMR-based metabolomic technique was used to investigate the antifungal mechanism of carvacrol against P. digitatum. The metabolomic profiling data showed that alanine, aspartate, glutamate, and glutathione metabolism were imbalanced in the fungal hyphae. A strong positive correlation was seen between aspartate, glutamate, alanine, and glutamine, with a negative correlation among glutathione and lactate. These metabolic changes revealed that carvacrol-induced oxidative stress had disturbed the energy production and amino acid metabolism of P. digitatum. The current study will improve the understanding of the metabolic changes posed by plant-based fungicides in order to control citrus fruit green mold caused by P. digitatum. Moreover, the study will provide a certain experimental and theoretical basis for the development of novel citrus fruit preservatives.aroused by excessive use of certain routine and synthetic antifungal agents. Over the past few decades, the intentions have been to ensure the hygiene and safety levels of fruit products along with promoting maximum biodegradability. In order to achieve this ambition, researchers are still trying to screen natural products with strong antifungal potential from plants. Moreover, it has also been tried to explore new preservation technologies that can replace synthetic fungicides. Compared with synthetic fungicides, natural antifungal substances have attained much attention in recent years [6][7][8][9].Various essential oils refined from Melaleuca alternifolia have strong inhibitory effects on multiple fungal strains, particularly P. italicum Wehmer and P. digitatum Sacc., and hence can be used as natural preservatives in agricultural and food processing [10]. Previously we have reported that cinnamaldehyde contained in cinnamon has a good antifungal effect against P. italicum and clarifies the method for dynamic detection of the antifungal effect of cinnamaldehyde [11]. In addition, GC-MS and GC-FID techniques successfully separated the essential oils components viz. limonene (87.02%), linalyl acetate (53.76%) and linalool (39.74%) from peels, leaves and flowers of Citrus aurantium var amara, neroli oil appeared as the best fungistatic agent, which reduced the P. digitatum sporulation to 25 % at a 50 mg/mL concentration of oil [12].Carvacrol (5-Isopropyl-2-methylphenol) is the major volatile oil constituent from Labiaceae family plants, such as oregano, mint, and thyme [13]. Carvacrol has many medicinal and edible applications, including antifungal, antimicrobial, anti-inflammatory, insecticidal, antitumor, and other effects [14]. Carvacrol inhibited the growth of P. digitatum and P. italicum in in vitro and in vivo experiments of l...

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WASP homolog associated with actin, membranes and microtubules (WHAMM) is a newly discovered nucleation-promoting factor that links actin and microtubule cytoskeleton and regulates transport from the endoplasmic reticulum to the Golgi apparatus. However, knowledge of WHAMM is limited to interphase somatic cells. In this study, we examined its localization and function in mouse oocytes during meiosis. Immunostaining showed that in the germinal vesicle (GV) stage, there was no WHAMM signal; after meiosis resumption, WHAMM was associated with the spindle at prometaphase I (Pro MI), metaphase I (MI), telophase I (TI) and metaphase II (MII) stages. Nocodazole and taxol treatments showed that WHAMM was localized around the MI spindle. Depletion of WHAMM by microinjection of specific short interfering (si)RNA into the oocyte cytoplasm resulted in failure of spindle migration, disruption of asymmetric cytokinesis and a decrease in the first polar body extrusion rate during meiotic maturation. Moreover, actin cap formation was also disrupted after WHAMM depletion, confirming the failure of spindle migration. Taken together, our data suggest that WHAMM is required for peripheral spindle migration and asymmetric cytokinesis during mouse oocyte maturation.

The combination of chiral derivatization and ion mobility-mass spectrometry provides the first insights into the separation of 19 pairs of chiral proteinogenic d/l-amino acids in a single run and detection of chiral amino acids in complex samples.

Axin-1, a negative regulator of Wnt signaling, is a versatile scaffold protein involved in centrosome separation and spindle assembly in mitosis, but its function in mammalian oogenesis remains unknown. Here we examined the localization and function of Axin-1 during meiotic maturation in mouse oocytes. Immunofluorescence analysis showed that Axin-1 was localized around the spindle. Knockdown of the Axin1 gene by microinjection of specific short interfering (si)RNA into the oocyte cytoplasm resulted in severely defective spindles, misaligned chromosomes, failure of first polar body (PB1) extrusion, and impaired pronuclear formation. However, supplementing the culture medium with the Wnt pathway activator LiCl improved spindle morphology and pronuclear formation. Downregulation of Axin1 gene expression also impaired the spindle pole localization of γ-tubulin/Nek9 and resulted in retention of the spindle assembly checkpoint protein BubR1 at kinetochores after 8.5 h of culture. Our results suggest that Axin-1 is critical for spindle organization and cell cycle progression during meiotic maturation in mouse oocytes.