The purified compound of M. alba showed an 8-fold greater reduction of MIC against S. mutans than the crude extract (MICs, 15.6 and 125 mg/L, respectively). The extract strongly inhibited biofilm formation of S. mutans at its active accumulation and plateau phases. The purified compound led to a 22% greater reduction in alkali-soluble polysaccharide than in water-soluble polysaccharide. The purified compound was found to be 1-deoxynojirimycin (DNJ). Confocal microscopy revealed that DNJ distorts the biofilm architecture of S. mutans. CONCLUSIONS The whole study reflects a prospective role of DNJ as a therapeutic agent by controlling the overgrowth and biofilm formation of S. mutans.

The genus Acacia comprising over 500 species, found in the warmer, drier parts of the World, chiefly in Arabia, Australia and Africa. 1 In India, there are about 22 indigenous species, distributed throughout the plains. Some of the Acacia species are of considerable value for reafforestation and reclamation of waste land. They are the good sources of tannin, gum and timber. 1 Acacia tortilis (Syn: A. raddiana Savi) (Leguminosae) was found to be a very useful source of protein. 2 The acid digest of cell wall constituents fibres and cellulose found in the leaves provide nutrients for the animals as fodder. 3 It is also used for the relaxation of smooth muscle. 4 Earlier investigations of this plant described the isolation of apigenin glycoside, 5 quercetin glycoside and isorhaminetin glycoside from leaves, 6 and n-hexacosanol, betulin, α-, β-amyrin and βsitosterol from the stem bark. 7 Medicinal properties and scanty work on this plant stimulated our interest to carry out its comprehensive investigation. We now report here the isolation and characterisation of a novel flavonoid 5,7-dihydroxy-4Ј-p-methyl benzyl isoflavone 4a, along with the three known flavonoids, apigenin, luteolin and quercetin from the leaves of Acacia tortilis.The dried and powdered leaves of Acacia tortilis (3 kg) procured from Yeman, were exhaustively extracted with light petroleum ether (60-80), benzene and finally with methanol respectively. The methanol extract was concentrated by heating over a boiling water bath under reduced pressure, and a brown gummy mass was obtained. It gave a positive colour test for flavonoids. 8 TLC examination in benzene-pyridineformic acid (BPF, 36:9:5) and toluene-ethylformate-formic acid (TEF, 5:4:1) systems showed it to be a mixture of several compounds. The brown gummy mass was purified by refluxing it with petroleum ether, benzene and chloroform. The semi-solid mass left behind was chromatographed over silica gel column. Fractional elution with benzene-ethylacetate

From leaves of Rhus alata, one new benzofuranic acid named [(2E)-3-(4-hydroxy-5,7-dimethyl- benzo[3,4-b] furan-6-yloxy)-prop-2-enoic acid has been isolated together with eight known compounds: dimethyl ester of terephthalic acid, beta-amyrin, friedelin, lupeol, beta-sitosterol, oleanolic acid, taraxerone and ethyl gallate. Structural elucidations were done on the basis of chemical and physical data (IR, UV, 1H-NMR, 13C-NMR and MS spectra).

An efficient method for the formation of new arylmethylidene steroidal compounds by the reaction of ketones with 4-(N,N-dimethylamino)benzaldehyde is described.

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