Variations in Essential Oil Chemical Composition and Biological Activities of Cryptomeria japonica (Thunb. ex L.f.) D. Don from Different Geographical Origins—A Critical Review

The scientific community is paying increasing attention to plant waste valorization, and also to “greener” practices in the agriculture, food and cosmetic sectors. In this context, unused forest biomass (e.g., leaves, seed cones, branches/twigs, bark and sapwood) of Cryptomeria japonica, a commercially important tree throughout Asia and the Azores Archipelago (Portugal), is currently waste/by-products of wood processing that can be converted into eco-friendly and high added-value products, such as essential oils (EOs), with social, environmental and economic impacts. Plant-derived EOs are complex mixtures of metabolites, mostly terpenes and terpenoids, with valuable bioactivities (e.g., antioxidant, anti-inflammatory, anticancer, neuroprotective, antidepressant, antimicrobial, antiviral and pesticide), which can find applications in several industries, such as pharmaceutical, medical, aromatherapy, food, cosmetic, perfumery, household and agrochemical (e.g., biopesticides), with manifold approaches. The EOs components are also of value for taxonomic investigations. It is known that the variation in EOs chemical composition and, consequently, in their biological activities and commercial use, is due to different exogenous and endogenous factors that can lead to ecotypes or chemotypes in the same plant species. The present paper aims to provide an overview of the chemical composition, biological properties and proposals of valorization of C. japonica EO from several countries, and also to indicate gaps in the current knowledge.

Production of 5-hydroxymethylfurfural from Japanese cedar (Cryptomeria japonica) in an ionic liquid, 1-methylimidazolium hydrogen sulfate

Production of 5-hydroxymethylfurfural (5-HMF) from Japanese cedar (Cryptomeria japonica) using an ionic liquid, 1-methylimidazolium hydrogen sulfate ([MIM]HSO4), was investigated. 5-HMF can be produced from C. japonica at temperatures above 120 °C. The maximum yield of 5-HMF was about 9 wt% after 15 min of treatment at 160 °C. However, 5-HMF produced in this process tended to decompose as the treatment continued. To avoid decomposition and to provide a means of recovering 5-HMF from [MIM]HSO4, three reaction systems based on [MIM]HSO4 were investigated: biphasic [MIM]HSO4/organic solvent system, [MIM]HSO4 with vacuum distillation, and [MIM]HSO4 with vacuum steam distillation. The [MIM]HSO4 reaction system combined with vacuum steam distillation was most effective. The maximum yield of 5-HMF was 17.5 wt% after treatment for 45 min at 160 °C. The combination of [MIM]HSO4 treatment with vacuum steam distillation is suitable for 5-HMF production because it is a one-pot process without the need for catalysts or pretreatment.

Development and application of a method to classify airborne pollen taxa concentration using light scattering data

Although automated pollen monitoring networks using laser optics are well-established in Japan, it is thought that these methods cannot distinguish between pollen counts when evaluating various pollen taxa. However, a method for distinguishing the pollen counts of two pollen taxa was recently developed. In this study, we applied such a method to field evaluate the data of the two main allergens in Japan, Chamaecyparis obtusa and Cryptomeria japonica. We showed that the method can distinguish between the pollen counts of these two species even when they are simultaneously present in the atmosphere. This result indicates that a method for automated and simple two pollen taxa monitoring with high spatial density can be developed using the existing pollen network.

The effects of different factors on propagation by hardwood cuttings of some coniferous ornamental plants

Chamaecyparis lawsoniana ‘Ellwoodii’, Cryptomeria japonica ‘Elegans’ and x Cupressocyparis leylandii have great importance in terms of usage areas as ornamental plant. The overcoming the problem, that may be encountered in generative propagation of these taxa, using vegetative propagation method are very important for producers dealing with park and garden works. It was investigated that the effects of different greenhouse medium, rooting medium and phytohormones on propagation by hardwood cutting of studied taxa. In this study, three greenhouse medium (Greenhouse-1, 2 and 3 medium), two rooting medium (perlite and peat) and four phytohormones (IBA 1000, IBA 5000, NAA 1000 and NAA 5000 ppm) were selected. The first root and callus formation dates, rooting percentage, callus percentage, root length and the number of roots were determined. The results showed that the highest rooting percentages for C. lawsoniana ‘Ellwoodii’ were obtained as 100% in peat rooting medium (IBA 1000 ppm) at Greenhouse-2 medium and Greenhouse-3 medium and perlite rooting medium (control) at Greenhouse-3 medium. On the other hand, the highest rooting percentages for C. japonica ‘Elegans’ were obtained as 100% in IBA 1000, IBA 5000 and NAA 1000 ppm treatments at Greenhouse-1 medium, while this value for x C. leylandii occurred in NAA 5000 ppm treatment (73.33%) at Greenhouse-2 medium, in perlite rooting medium for both. The conditions required for the best rooting in cutting propagation vary according to the species studied, and generally, auxin applications, rooting medium temperature 5 °C higher than air temperature and use of perlite rooting medium can be recommended.

Marker-Assisted Selection for Pollen-Free Somatic Plants of Sugi (Japanese Cedar, Cryptomeria japonica): A Simple and Effective Methodology for Selecting Male-Sterile Mutants With ms1-1 and ms1-2

Pollen allergy caused by sugi (Japanese cedar, Cryptomeria japonica) is a serious problem in Japan. One of the measures against pollinosis is the use of male-sterile plants (MSPs; pollen-free plants). In this context, the development of a novel technique for the efficient production of sugi MSPs, which combines marker-assisted selection (MAS) with somatic embryogenesis (SE), was recently reported by our research group. To improve the efficiency of MSP production, in this paper we report improved MAS for male-sterile individuals from embryogenic cells, cotyledonary embryos, and somatic plants of sugi using a newly developed marker in the form of the causative mutation of MS1 itself, selecting individuals with ms1-1 and ms1-2 male-sterile mutations. We also describe simplified methods for extracting DNA from different plant materials and for MAS using LAMP diagnostics. Finally, we show that MAS can be efficiently performed using the one-step indel genotyping (ING) marker developed in this study and using InstaGene for DNA extraction. The combination of SE and 100% accurate marker selection during the embryogenic cell stage enables the mass production of MS1 male-sterile sugi seedlings.