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Further phytochemical investigation of the aerial parts of Cyperus rotundus L. afforded a new steroid glycoside named sitosteryl (6'-hentriacontanoyl)-beta-D-galactopyranoside (4) in addition to three furochromones, khellin (2), visnagin (3) and ammiol (9). Furthermore, benzo-alpha-pyrone (coumarin) (1), salicylic acid (5), caffeic acid (6), protocatechuic acid (7), p-coumaric acid (8), tricin (10) and isorhamnetin (11) were isolated. The structures of these compounds were established by spectroscopic methods. The isolated furochromones were tested for insect antifeedant activity against larvae Spodoptera littoralis when incorporated in artificial diet and offered to larvae in a chronic feeding bioassay. Also, visnagin, khellin and sitosteryl (6'-hentriacontanoyl)-beta-D-galactopyranoside showed strong cytotoxic activity against L5178y mouse lymphoma cells and were also active in the brine shrimp lethality test.

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This work presents three kinetic models based on a lumping approach to describe the microwave pyrolysis of kraft lignin. The first model considered the formation of the main pyrolysis products, condensable gas, non-condensable gas, and remaining solid, taking into consideration each as an individual lump. The second model investigated the liquid product while dividing the condensable gas into oil and water products. The oil product contains only chemicals, whereas the water product does not contain any chemicals. In the third model, the oil product was separated into four main groups: (1) phenolics, which contain all of the identified phenolic components using a gas chromatography–mass spectrometry (GC–MS) analyzer, (2) heavy-molecular-weight components, which contain all of the identified heavy-molecular-weight and undefined components, using GC–MS, (3) non-phenolic aromatics with a single ring, and (4) aliphatics. The comparison of the predicted results using the estimated kinetic parameters to the experimental data showed the high capability of the presented models to estimate the product yield under the selected conditions.

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Further phytochemical study on the aerial parts of Cyperus rotundus L. led to the isolation of a fructose-amino acid conjugate, N-(1-deoxy-alpha-D-fructos-1-yl)-L-tryptophan (16) and its tautomers, in addition to n-butyl-beta-D-fructopyranoside (1), ethyl-alpha-D-glucopyranoside (2), adenosine (3), (-)-(E)-caffeoylmalic acid (4), vitexin (5), isovitexin (6), orientin (7), epiorientin (8), myricetin 3-O-beta-D-galactopyranoside (9), luteolin 7-O-beta-D-glucuronopyranoside-6''-methyl ester (10), chlorogenic acid (11), luteolin 4'-O-beta-D-glucuronopyranoside (12), luteolin 7-O-beta-D-glucuronopyranoside (13), uridine (14) and ellagic acid (15). Their structures were elucidated on the basis of spectroscopic methods. Additionally, antioxidant and alpha-amylase inhibitory activities of some of the isolated phenolic compounds were carried out.