Analysis of composition, morphology, and biosynthesis of cuticular wax in wild type bilberry (Vaccinium myrtillus L.) and its glossy mutant

Plant In Vitro Culture Factories for Pentacyclic Triterpenoid Production

Pentacyclic triterpenoids are a diverse subclass of naturally occurring terpenes with various biological activities and applications. These compounds are broadly distributed in natural plant resources, but their low abundance and the slow growth cycle of plants pose challenges to their extraction and production. The biosynthesis of pentacyclic triterpenoids occurs through two main pathways, the mevalonic acid (MVA) pathway and the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway, which involve several enzymes and modifications. Plant in vitro cultures, including elicited and hairy root cultures, have emerged as an effective and sustainable system for pentacyclic triterpenoid production, circumventing the limitations associated with natural plant resources. Bioreactor systems and controlling key parameters, such as media composition, temperature, light quality, and elicitor treatments, have been optimized to enhance the production and characterization of specific pentacyclic triterpenoids. These systems offer a promising bioprocessing tool for producing pentacyclic triterpenoids characterized by a low carbon footprint and a sustainable source of these compounds for various industrial applications.

Comprehensive phytochemical analysis of lingonberry (Vaccinium vitis-idaea L.) from different regions of China and their potential antioxidant and antiproliferative activities

Lingonberry are underutilised due to the lack of evaluating active compounds in different parts. In this study, the phytochemical profiles, antioxidant and antiproliferative activities of lingonberry's fruits, leaves and stems from different regions of China were compared. Ninety-five bioactive compounds were rapidly identified using a molecular network based on UPLC-Q-Exactive Orbitrap mass spectrometry. The UPLC-QqQ-MS/MS method combined with principal component analysis (PCA) quantified 18 bioactive components in 6 classes. The highest content of arbutin (15 mg/100 g DW) was found in leaves of Huzhong (P6). Ursolic acid and cyanidin-3-O-galactoside were highest in fruits of Tahe (P4) (4.5 mg/100 g DW and 3.2 mg/100 g DW, respectively). Antioxidant activities determined by DPPH, ABTS+ and FRAP methods were significantly correlated with total phenolic content (TPC), total flavonoid content (TFC) and total anthocyanin content (TAC). The results indicate that the strongest antioxidant activity and antiproliferative efficacy are observed in the fruits of Tahe (P4) and leaves of Huzhong (P6), respectively. Our results provide valuable insights into lingonberry's comprehensive development and utilization.

The dynamic changes of mango (Mangifera indica L.) epicuticular wax during fruit development and effect of epicuticular wax on Colletotrichum gloeosporioides invasion

Mango fruits are susceptible to diseases, such as anthracnose, during fruit development, leading to yield reduction. Epicuticular wax is closely related to resistance of plants to pathogenic bacterial invasion. In this study, the effect of mango fruit epicuticular wax on the invasion of Colletotrichum gloeosporioides was investigated, followed by to understand the changes of wax chemical composition and crystal morphology during mango fruit development using GC-MS and SEM. Results showed that the epicuticular wax of mango fruits can prevent the invasion of C. gloeosporioides, and 'Renong' showed the strongest resistance to C. gloeosporioides. The wax content of four mango varieties first increased and then decreased from 40 days after full bloom (DAFB) to 120 DAFB. In addition, 95 compounds were detected in the epicuticular wax of the four mango varieties at five developmental periods, in which primary alcohols, terpenoids and esters were the main wax chemical composition. Furthermore, the surface wax structure of mango fruit changed dynamically during fruit development, and irregular platelet-like crystals were the main wax structure. The present study showed the changes of wax content, chemical composition and crystal morphology during mango fruit development, and the special terpenoids (squalene, farnesyl acetate and farnesol) and dense crystal structure in the epicuticular wax of 'Renong' fruit may be the main reason for its stronger resistance to C. gloeosporioides than other varieties. Therefore, these results provide a reference for the follow-up study of mango fruit epicuticular wax synthesis mechanism and breeding.

Vaccinium uliginosum and Vaccinium myrtillus-Two Species-One Used as a Functional Food

Vaccinium uliginosum L. (commonly known as bog bilberry) and Vaccinium myrtillus L. (commonly known as bilberry) are species of the genus Vaccinium (family Ericaceae). The red-purple-blue coloration of blueberries is attributed largely to the anthocyanins found in bilberries. Anthocyanins, known for their potent biological activity as antioxidants, have a significant involvement in the prophylaxis of cancer or other diseases, including those of metabolic origin. Bilberry is the most important economically wild berry in Northern Europe, and it is also extensively used in juice and food production. A review of the latest literature was performed to assess the composition and biological activity of V. uliginosum and V. myrtillus. Clinical studies confirm the benefits of V. uliginosum and V. myrtillus supplementation as part of a healthy diet. Because of their antioxidant, anti-inflammatory, anti-cancer, and apoptosis-reducing activity, both bog bilberries and bilberries can be used interchangeably as a dietary supplement with anti-free radical actions in the prevention of cancer diseases and cataracts, or as a component of sunscreen preparations.

Composition, metabolism and postharvest function and regulation of fruit cuticle: A review

The cuticle of plants, a hydrophobic membrane that covers their aerial organs, is crucial to their ability to withstand biotic and abiotic stressors. Fruit is the reproductive organ of plants, and an important dietary source that can offer a variety of nutrients for the human body, and fruit cuticle performs a crucial protective role in fruit development and postharvest quality. This review discusses the universality and diversity of the fruit cuticle composition, and systematically summarizes the metabolic process of fruit cuticle, including the biosynthesis, transport and regulatory factors (including transcription factors, phytohormones and environmental elements) of fruit cuticle. Additionally, we emphasize the postharvest functions and postharvest regulatory technologies of fruit cuticle, and propose future research directions for fruit cuticle.

The Relationships between Waxes and Storage Quality Indexes of Fruits of Three Plum Cultivars

In the present study, the cuticular wax morphology, composition and the relationship with storage quality in three plum cultivars of Prunus salicina 'Kongxin' (KXL), Prunus salicina 'Fengtang' (FTL) and Prunus salicina 'Cuihong' (CHL) were investigated during storage at room temperature of 25 ± 1 °C. The results illustrated that the highest cuticular wax concentration was discovered in KXL, followed by FTL and the lowest in CHL. The fruit wax composition of the three plum cultivars was similar and principally composed of alkanes, alcohols, fatty acids, ketones, aldehydes, esters, triterpenes and olefins. Alcohols, alkanes and triterpenes were the dominant fruit wax compounds of the three plum cultivars. After storage for 20 d at room temperature, the variation of cuticular wax crystal structure and composition showed significant cultivar-associated differences. The total wax content decreased for FTL and CHL and increased for KXL, and the wax crystal degraded and melted together over time. The higher contents of the main components in the three plum cultivars were nonacosane, 1-triacontanol, 1-heneicosanol, nonacosan-10-one, octacosanal, ursolic aldehyde and oleic acid. Alcohols, triterpenes, fatty acids and aldehydes were most dramatically correlated with the softening of fruit and storage quality, and alkanes, esters and olefins were most significantly correlated with the water loss. Nonacosane and ursolic aldehyde can enhance the water retention of fruit. Overall, this study will provide a theoretical reference for the further precise development of edible plum fruit wax.

Temperature has a major effect on the cuticular wax composition of bilberry (Vaccinium myrtillus L.) fruit

Cuticle is the first layer protecting plants against external biotic and abiotic factors and is responsive to climatic factors as well as determined by genetic adaptations. In this study, the chemical composition of bilberry fruit cuticular wax was investigated through a latitudinal gradient from Latvia (56°N 24°E) through Finland (65°N 25°E) to northern Norway (69°N 18°E) in two seasons 2018 and 2019. Changes in the major cuticular wax compounds, including triterpenoids, fatty acids, alkanes, aldehydes, ketones, and primary alcohols, were detected by GC-MS analysis. Generally, a decreasing trend in the proportion of triterpenoids from southern to northern latitudes, accompanied with an increase in proportion of fatty acids, aldehydes, and alkanes, in bilberry fruit cuticular wax was observed. A correlation analysis between climatic factors with proportion of wax compounds indicated that temperature was the main factor affecting the cuticular wax composition in bilberries. A controlled phytotron experiment with southern and northern bilberry ecotypes confirmed the major effect of temperature on bilberry fruit cuticular wax load and composition. Elevated temperature increased wax load most in berries of northern ecotypes. The level of triterpenoids was higher, while levels of fatty acids and alkanes were lower, in wax of bilberry fruits ripened at 18°C compared to 12°C in both northern and southern ecotypes. Based on our results, it can be postulated that the predicted increase in temperature due to climate change leads to alterations in fruit cuticular wax load and composition. In northern ecotypes, the alterations were especially evident.

Molecular Biology, Composition and Physiological Functions of Cuticle Lipids in Fleshy Fruits

Fleshy fruits represent a valuable resource of economic and nutritional relevance for humanity. The plant cuticle is the external lipid layer covering the nonwoody aerial organs of land plants, and it is the first contact between fruits and the environment. It has been hypothesized that the cuticle plays a role in the development, ripening, quality, resistance to pathogen attack and postharvest shelf life of fleshy fruits. The cuticle's structure and composition change in response to the fruit's developmental stage, fruit physiology and different postharvest treatments. This review summarizes current information on the physiology and molecular mechanism of cuticle biosynthesis and composition changes during the development, ripening and postharvest stages of fleshy fruits. A discussion and analysis of studies regarding the relationship between cuticle composition, water loss reduction and maintaining fleshy fruits' postharvest quality are presented. An overview of the molecular mechanism of cuticle biosynthesis and efforts to elucidate it in fleshy fruits is included. Enhancing our knowledge about cuticle biosynthesis mechanisms and identifying specific transcripts, proteins and lipids related to quality traits in fleshy fruits could contribute to the design of biotechnological strategies to improve the quality and postharvest shelf life of these important fruit crops.

Dispersal of taeniid eggs: Experimental faecal contamination of forest environment followed by DNA detection in wild berries

To understand Taeniidae epidemiology, the principles of egg-dispersion dynamics under natural conditions must be known. In this study, non-zoonotic Taenia laticollis was used as a model parasite for the family Taeniidae (including Echinococcus spp.). An experiment to investigate dispersion from contaminated faeces to the surroundings was performed both with bilberries (Vaccinium myrtillus) and lingonberries (Vaccinium vitis-idaea), both of which are commercially harvested wild berries in Finland. For this experiment, 30 g of fox faeces was inoculated with 30,000 T. laticollis eggs for the bilberry experiment and 100,000 eggs for the lingonberry experiment. The faecal material was placed in the middle of good berry growth areas in four locations for bilberries and eight locations for lingonberries. After 41–42 days, berries at different distances (0–15 m) from the original contamination spot were collected and delivered to our laboratory. DNA was extracted from washed and sieved material and analysed using T. laticollis-specific semi-quantitative SYBR Green real-time polymerase chain reaction (qPCR). Taenia laticollis-specific DNA was recovered from 67% (8/12) of bilberry samples but not reliably from any of the lingonberry samples 0% (0/24), although the exposure dose was higher for those. The qPCR results suggest that under natural conditions, taeniid egg dispersion from the contamination spot is demonstrated but attachment is berry specific. The surface of bilberries may be more adhesive for taeniid eggs than the waxier and harder pericarp of the lingonberries or there might be a difference in the dispersal mechanism caused by different biotopes.

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Experimental dispersal of non-zoonotic taeniid eggs was used as a model for pathogenic Taeniidae as Echinococcus spp.

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Taeniid DNA was detected from wild bilberries under natural conditions after over a month from different distances.

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Parasitic egg dispersal was evident to bilberries but not to the lingonberries.

Fractional Separation and Characterization of Cuticular Waxes Extracted from Vegetable Matter Using Supercritical CO2

Cuticular waxes can be used in high-value applications, including cosmetics, foods and nutraceuticals, among the others. The extraction process determines their quality and purity that are of particular interest when biocompatibility, biodegradability, flavor and fragrance are the main features required for the final formulations. This study demonstrated that supercritical fluid extraction coupled with fractional separation can represent a suitable alternative to isolate cuticular waxes from vegetable matter that preserve their natural properties and composition, without contamination of organic solvent residues. Operating in this way, cuticular waxes can be considered as a fingerprint of the vegetable matter, where C27, C29 and C31 are the most abundant compounds that characterize the material; the differences are mainly due to their relative proportions and the presence of hydrocarbon compounds possessing other functional groups, such as alcohols, aldehydes or acids. Therefore, selectivity of supercritical fluid extraction towards non-polar or slightly polar compounds opens the way for a possible industrial approach to produce extracts that do not require further purification steps.

Comparative Analysis of Cuticular Wax in Various Grape Cultivars During Berry Development and After Storage

Cuticular wax covering the surface of fleshy fruit is closely related to fruit glossiness, development, and post-harvest storage quality. However, the information about formation characteristics and molecular mechanisms of cuticular wax in grape berry is limited. In this study, crystal morphology, chemical composition, and gene expression of cuticular wax in grape berry were comprehensively investigated. Morphological analysis revealed high density of irregular lamellar crystal structures, which were correlated with the glaucous appearances of grape berry. Compositional analysis showed that the dominant wax compounds were triterpenoids, while the most diverse were alkanes. The amounts of triterpenoids declined sharply after véraison, while those of other compounds maintained nearly constant throughout the berry development. The amounts of each wax compounds varied among different cultivars and showed no correlation with berry skin colors. Moreover, the expression profiles of related genes were in accordance with the accumulation of wax compounds. Further investigation revealed the contribution of cuticular wax to the water preservation capacity during storage. These findings not only facilitate a better understanding of the characteristics of cuticular wax, but also shed light on the molecular basis of wax biosynthesis in grape.