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Royal jelly (RJ) is a bee product that has high nutritional value and is beneficial for the human health, earning importance as a functional food. Thus, the characterization of its main biological properties is with high importance. In this work, 6 RJ samples obtained in Morocco, Portugal, and Spain were evaluated in terms of total phenol and flavone/flavonol contents; total protein; 10-hydroxy-2-decenoic acid (10-HDA); volatiles composition; antioxidant and anti-inflammatory properties; and inhibition of tyrosinase, xanthine oxidase (XO), and acetylcholinesterase (AChE) activities. Total phenolic content ranged from 3 to 9 mg gallic acid equivalent/g RJ, and flavone/flavonol content from 0.1 to 0.5 mg quercetin equivalent/g RJ. 10-Hydroxy-2-decenoic acid content varied from 0.9% to 1.2% and total protein from 5.5% to 29.7%. Gas chromatography-flame ionization detector and gas chromatography-mass spectrometry analysis showed RJ volatiles dominated by linolenic acid, 2-decenoic acid, and octanoic acid in variable amounts. The antioxidant activity was monitored through nitric oxide (NO) scavenging activity and hydrogen peroxide (H 2 O 2 ) scavenging capacity, where the IC 50 ranged from 2.3 to 3.4 and 0.2 to 1.5 mg/mL, respectively. Anti-AChE activity IC 50 ranged from 0.7 to 4.6 mg/mL, while XO inhibition IC 50 ranged from 3.3 to 11.9 mg/mL. The results showed that phenols and flavonoids highly contributed to the RJ biological properties in contrast to 10-HDA and proteins.Honeybees, Apis mellifera, are a source of a variety of precious and valuable natural products with health-promoting bioactive compounds including honey, bee bread, bee venom, bee pollen, propolis, and royal jelly (RJ). 1 Royal jelly is a milky-white and strongly acidic (pH 3.1-3.9) fluid produced by the hypopharyngeal and mandibular glands of A. mellifera L. young worker honeybees (called nurses). 2 Royal jelly serves as the most important part of honeybee larvae diet, playing a major role in caste differentiation. It is the food given to all young larvae of workers and drones in their maturation process, whereas the queen honeybee is fed RJ for her entire life cycle and nurse honeybees are fed RJ for only 3 days after which worker larvae are fed a mixture of RJ, pollen, and honey. 3 Royal jelly was found to be mainly composed of water (50%-70%), proteins (9%-18%), carbohydrates (7%-18%), lipids (3%-8%), mineral salts (1.5%), vitamins, polyphenols, enzymes, and hormones. 4 A unique and chemically interesting feature in RJ is its lipidic fraction, where 80% to 85% are uncommon short chain hydroxy and dicarboxylic free fatty acids, with 8 to 12 carbon atoms. 2 The main compound,

a b s t r a c tThe photocatalytic activities of Degussa P25 powders annealed at various temperatures in vacuum and air were studied together with investigations of their compositions by XPS, of their crystal structures by XRD and of their specific surface areas by BET. It is shown that the photocatalytic activity of P25 powders was remarkably enhanced after vacuum annealing; the kinetic coefficient can be raised by 75% during annealing at 400 • C. It is obvious that this enhancement is not related to the adhesion ability of the P25 powders.

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AbstractÐThe rate of photodegradation of the fungicide fenarimol (a-(2-chlorophenyl)-a-(4-chlorophenyl)-5-pyrimidine-methanol) by solar radiation has been studied in natural waters with dierent salinities. Photodegradation rates and quantum yields are found to decrease with increasing salinity.To explain this behaviour, experiments were performed with dierent salt solutions (NaCl, NaBr, BaCl 2 and ZnCl 2 ) using both solar irradiation and a photoreactor (l excit 313 nm). As with natural waters, marked eects of added salt were observed on the photolysis rate, which decreased signi®cantly from 0.67 h À1 in the absence of salt to 0.11 h À1 in the presence of BaCl 2 . In photoreactor studies, the observed order of quenching was BaCl 2 > ZnCl 2 and NaBr > NaCl. In contrast, neither the triplet state quencher sorbic acid nor oxygen had any eect on the photolysis, supporting the idea that photodegradation goes by the lowest excited singlet state of fenarimol.To understand the origin of the eect of added salts,¯uorescence quenching studies have been performed with various halide and nonhalide salts and the respective quenching constants determined. With NaCl and NaBr, the ratio of¯uorescence quenching constants is identical to the ratio of reciprocal quantum yields for photodegradation of fenarimol, indicating a common mechanism. The correlation of¯uorescence quenching rates with halide ion oxidation potentials strongly suggests that this involves an electron transfer mechanism. It is suggested that the eect may be used to stabilise the fungicide towards photodegradation. #