Structure-function activity of dehydrozingerone and its derivatives as antioxidant and antimicrobial compounds.

Dehydrozingerone, structural half analogue of curcumin, is a phenolic compound isolated from ginger (Zingiber officinale) rhizomes. Dehydrozingerone and several of its derivatives such as glucopyranosides and its tetra acetate derivative and 4-O-acetyl and methyl derivatives of dehydrozingerone were synthesized in the present study. Dehydrozingerone, synthesised with improved yield was used for the synthesis of Dehydrozingerone 4-O-ß-D-glucopyranoside (first time report) by modified Koenigs-Knorr-Zemplén method. Structures of all the compounds have been established using spectroscopic methods. These compounds were tested for radical scavenging activity by DPPH and FRAP method as well as for antibacterial and antifungal activities. The parent molecule exhibited better scavenging activity as compared to its derivatives indicating the significance of free phenolic hydroxyl group. Also, Dehydrozingerone and its derivatives exhibited antibacterial as well as antifungal activity due to the conjugation system present, which includes α,ß-unsaturated carbonyl (C = O) group. This study gave an insight into structural requirements for dehydrozingerone activity.

An overview on chemical composition, bioactivity and processing of leaves of Cinnamomum tamala.

Dried leaves of Cinnamomum tamala, also known as Indian bay leaves, are a lesser-known spice used in the Indian subcontinent. It imparts a warm, peppery, clove-cinnamon like flavor to a variety of food preparations. Besides food applications, the leaves have also been traditionally used for curing a number of ailments and for other perceived health benefits. They find mention in the Aurvedic, Yunani, and other traditional medicinal literature. This review summarizes the effect of Cinnamomum tamala leaves on biological systems such as immune system, gastro-intestinal tract, liver and its antioxidant, antidiabetic, anti-inflammatory, anticancer, and antimicrobial activity. Chemical components that may be responsible for its flavor as well as bioactivity, have also been discussed.

Occurrence of antioxidant and radical scavenging proanthocyanidins from the Indian minor spice nagkesar (Mammea longifolia planch and triana syn).

Nagkesar (buds of Mammea longifolia) is extensively used in culinary preparations especially in spice blend in India. Previously thirteen compounds were identified from the medium polar fractions of methanol extract of buds of M. longifolia. In continuation of the study, the polar fraction of methanol extract exhibited stronger antioxidative and radical scavenging activities. An attempt was made to separate and identify the active compounds and found that those were proanthocyanidin oligomers with mean degree of polymerisation ranges from 2 to 10. This is the first report to indicate that Mammea buds contain antioxidant and radical scavenging procyanidin oligomers.

Determination of 2-hydroxy-4-methoxybenzaldehyde in roots of Decalepis hamiltonii (Wight & Arn.) and Hemidesmus indicus R.Br.

The roots of Decalepis hamiltonii and Hemidesmus indicus are aromatic and possess the crystalline compound 2-hydroxy-4-methoxybenzaldehyde as the major compound (> 90%) in their volatile oils. A gas chromatographic procedure was developed for the assay of 2-hydroxy-4-methoxybenzaldehyde in both fresh and dried roots of different origin. Benzyl butyrate was used as the internal standard. Among the methods tried, steam hydrodistillation was suitable for extraction of the volatile oils. The quantity of this aromatic compound varied from 0.03 to 0.54%.