Morpho-Anatomical Characterization of the Raisin Tree, Hovenia dulcis Thunb., Utilizing Optical Light and Scanning...

Area of Science:

• Botany
• Pharmacognosy
• Plant Anatomy

Background:

• Hovenia dulcis Thunb. (Rhamnaceae), the Chinese or Japanese raisin tree, is a valuable medicinal plant in Traditional Chinese Medicine.
• Existing morpho-anatomical standards for H. dulcis raw material authentication and quality control are insufficient.
• All plant organs of H. dulcis are traditionally used for therapeutic purposes, highlighting the need for reliable identification methods.

Purpose of the Study:

• To investigate the detailed morpho-anatomy of vegetative and reproductive organs of Hovenia dulcis.
• To establish reliable anatomical and micromorphological parameters for the authentication and quality control of H. dulcis raw materials.
• To contribute to systematic studies within the Rhamnaceae family.

Main Methods:

• Light microscopy was employed to examine the internal structures of H. dulcis organs.
• Scanning electron microscopy (SEM) was used for detailed micromorphological analysis.
• Morphological descriptions and anatomical features of leaves, stems, flowers, fruits, and seeds were documented.

Main Results:

• H. dulcis exhibits distinct morphological features like glossy leaves, a fleshy peduncle, and capsular fruits with linear hilum seeds.
• Anatomical findings include a sclerenchyma ring in the stem, homogenous leaves with atypical palisade mesophyll, hypostomatic nature, and specific stoma types (anomocytic, actinocytic).
• Unique features such as marginal extrafloral nectaries, mucilaginous cavities in most organs, and various inorganic crystals were observed.

Conclusions:

• The identified morpho-anatomical and micromorphological traits serve as crucial parameters for authenticating Hovenia dulcis raw materials.
• These findings enhance quality control measures for traditional medicines derived from H. dulcis.
• The study provides valuable data for the systematic classification of plants within the Rhamnaceae family.