Research Articles (STID)

Permanent URI for this collection

http://hdl.handle.net/11070/707

Browse

Browsing Research Articles (STID) by Type "Book chapter"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Chapter 4 - Clove (Syzygium aromaticum) polysaccharides
    (Elsevier, 2022) Cheikhyoussef, Ahmad
    Clove (Syzygium aromaticum (L.) Merr. & Perry) is an essential herb with well-documented health benefits. Carbohydrates were detected in the ethanolic bud extract of S. aromaticum. Two antithrombotic polysaccharides were isolated from the flower buds of clove by anion-exchange chromatography, hydrophobic interaction column chromatography, and size exclusion chromatography with molecular weight ranging from ca. 34,000 to ca. 103,000 Da. Clove polysaccharides have the backbone of type I rhamnogalacturonan, and the side chain of arabinan with the sulfate is being positioned at 6 of 3-linked galactosyl residues. Although polysaccharides from cloves have an antithrombotic ability, their activities in vitro are lower than that of heparin. Sulfated polysaccharides from cloves show a slightly lower salt concentration due to their relatively low sulfate/sugar ratio, which gives distinctive structural characteristics compared to other polysaccharides such as algae polysaccharides. The anticoagulation action with no toxicity in vivo of low molecular weight sulfated polysaccharide may represent a valuable and safe antithrombotic agent. This chapter gives an overview of polysaccharides from S. aromaticum, their characteristics, and their potential applications.
  • Thumbnail Image
    Item
    Clove (Syzygium aromaticum) phenolics: Extraction, compositions, and biological activities
    (Elsevier, 2022) Cheikhyoussef, Ahmad
    Clove (Syzygium aromaticum L.) is a dried flower bud belonging to the Myrtaceae family indigenous to Indonesia. Recently, it has been farmed in different places worldwide with potential food and nutraceutical applications. Clove volatile compounds contribute to the smell and unique aroma; meanwhile, nonvolatile compounds in the clove are mainly responsible for the taste. Clove is well known for its high level of antioxidants because of the flavonoids, hydroxy benzenes, phenylpropanoids, and other reducing substances. Clove phenolics comprise between 8% and 12% (w/w) gallic acid equivalents and are mainly composed of hydrolyzable tannins, phenolic acids, flavonoids, and eugenol, major bioactive molecules in this valuable herb. Gallic acid is the highest among the phenolic acids in clove and other gallic acid derivatives such as hydrolyzable tannins, which are also present in higher concentrations. Other phenolic acids found in the clove are ellagic, ferulic, caffeic, and salicylic acids. In addition, flavonoids such as quercetin and kaempferol were reported. This chapter will focus on clove phenolics’ structure, composition, and biological activities.