Antioxidant extracts from Dicerocaryum senecioides as active ingredients in semi-permanents and hair conditioners.

BACKGROUND: Different hair types respond differently to cosmetic treatments; hence, many options ought to be availed to the consumer. The purpose of this study was to evaluate the use of antioxidant extract from Dicerocaryum senecioides as active alternatives in hair semi-permanent waving and hair conditioning. METHODS: The antioxidant phytochemicals were first identified and isolated by thin-layer chromatography (TLC) and spraying with revealing agents. The antioxidant potency was determined by DPPH antiradical scavenging and ferric reducing power methods. The extract was incorporated in two different formulations to make the extract perm (bio-semi-permanent) and the antioxidant hair conditioner (AC). The formulations had their performance examined for hair curling and conditioning on Asian and African hair types. Hair damage was assessed by scanning the surface of treated samples on an attenuated total reflectance-Fourier transform infrared spectrometer (ATR-FTIR) and by quantifying lost protein on ultraviolet visible (UV-Vis) spectrophotometer. RESULTS: The extract antioxidant had an IC50 of 26.54 ± 0.34 µg/ml exhibiting greater antioxidant potency compared to the controls quercetin (38.84 ± 0.12 µg/ml) and ascorbic acid (35.22 ± 0.07 µg/ml). The extract perm had a lower curling ability indicated by a perm set of 85.10 ± 3.92% and 81.35 ± 2.35% for Asian and African hairs, respectively, while commercial product, ammonium thioglycolate (ATG) had 96.05 ± 1.70% and 93.60 ± 2.21% for the same. The curling of hair with extract perm resulted in less oxidative damage with oxidative peak areas of 3.37 ± 0.09 and 3.71 ± 0.03 as well as lower protein losses of 4.72 ± 0.71 µg/mg and 5.62 ± 0.70 µg/mg on Asian and African hair samples, respectively. The application of AC reduced the oxidative damage peak areas of ATG and extract perm treated Asian hair samples by 1.15 and 0.48 units, respectively. AC was also effective in reducing damage caused by UV radiation on ATG-treated samples by 1.06 units (African hair) and 1.09 units on Asian hair. CONCLUSION: The results show antioxidant extracts from Dicerocryum senecioides as a promising and safer alternative for hair conditioning and semi-permanent curling.

CONTEXTE: les réactions aux traitements cosmétiques varient d'un type de cheveux à l'autre. Ainsi, de nombreuses options doivent être mises à disposition des consommateurs. Cette étude avait pour objectif d'évaluer l'utilisation d'un extrait antioxydant de Dicerocaryum senecioides en vue de proposer de nouveaux choix de produits actifs pour les mises en plis semi-permanentes et le conditionnement capillaire. MÉTHODES: les agents phytochimiques antioxydants ont d'abord été identifiés et isolés par chromatographie sur couche mince (CCM) et par pulvérisation d'agents révélateurs. La puissance antioxydante a été déterminée par une méthode de piégeage antiradicalaire à l'aide du DPPH et par un procédé de puissance de réduction du fer. L'extrait a été incorporé dans deux formulations différentes pour obtenir la permanente (semi-permanentes biologiques) et l'après-shampooing capillaire antioxydant. Les performances des formulations ont été évaluées selon des critères de bouclage et conditionnement capillaires sur des cheveux de types asiatiques et africains. L'évaluation des lésions capillaires reposait sur un examen de la surface des échantillons traités à l'aide d'un spectromètre infrarouge à transformée de Fourier en réflectance totale atténuée (attenuated total reflectance Fourier transform infra-red spectrometer, ATR-FTIR) et sur une quantification des protéines perdues à l'aide d'un spectrophotomètre à ultraviolet visible (UV-Vis). RÉSULTATS: l'extrait antioxydant présentait une concentration inhibitrice médiane (IC50 ) de 26.54 ± 0.34 µg/ml, d'où une plus grande puissance antioxydante par rapport aux produits témoins, à savoir la quercétine (38.84 ± 0.12 µg/ml) et l'acide ascorbique (35.22 ± 0.07 µg/ml). La permanente présentait une plus faible capacité de bouclage, révélée par un taux de fixation de la permanente de 85.10 ± 3.92 % et de 81.35 ± 2.35 % pour les cheveux asiatiques et africains respectivement, tandis que le produit disponible dans le commerce, à savoir le thioglycolate d'ammonium (ATG), donnait des taux de 96.05 ± 1.70 % et de 93.60 ± 2.21 % dans les mêmes conditions. Le bouclage des cheveux à l'aide de la permanente a entraîné moins de lésions oxydatives, avec des zones de pics d'oxydation de 3.37 ± 0.09 et de 3.71 ± 0.03, ainsi que des pertes protéiques plus faibles, de 4.72 ± 0.71 µg/mg et de 5.62 ± 0.70 µg/mg sur les échantillons de cheveux asiatiques et africains respectivement. L'application de l'après-shampooing antioxydant a permis de réduire de 1.15 unité les zones de pics d'oxydation due à l'ATG sur les échantillons de cheveux asiatiques et la permanente a permis de traiter ces mêmes échantillons à raison de 0.48 unité. L'après-shampooing antioxydant s'est également avéré efficace pour réduire les lésions causées par les rayons UV sur les échantillons traités par ATG, de 1.06 unité sur les cheveux africains et de 1.09 unité sur les cheveux asiatiques. CONCLUSION: les résultats montrent que les extraits antioxydants de Dicerocaryum senecioides constituent une option prometteuse et plus sûre pour le conditionnement capillaire et les mises en pli semi-permanentes.

Persistence and fate of chlortetracycline in the aquatic environment under sub-tropical conditions: generation and dissipation of metabolites.

The persistence of chlortetracycline in the aquatic environment, including the generation and dissipation of its metabolites, were investigated over a period of 90 days using microcosm experiments, with a view to establishing the metabolites generated and their persistence under conditions closely resembling the actual aquatic environment in terms of chemical and microbial composition. The concentrations of chlortetracycline and its metabolites were monitored in the water phase as well as the sediment phase. Data are presented showing that the degradation of chlortetracycline in each phase conforms to a triphasic linear rate law, confirming the existence of three speciation forms in each phase, attributed to one free dissolved form, and two colloidal particle adsorbed forms. Data are also presented showing that the two adsorbed forms are the most persistent, with life-times of 204.1 and 20.3 days respectively in the water phase, and 215.1 and 19.8 days respectively in the sediment phase. Life-times of 5.01 and 3.7 days respectively were obtained for the free dissolved forms in the water phase and sediment phase respectively. Data are further presented showing that of the several metabolites of chlortetracycline reported previously, only 4-epi-chlortetracycline and iso-chlortetracycline could be detected, and that these two degradation products undergo microbial mineralization without transformation to other intermediate degradation products in significant or detectable amounts.

TLC separation and antioxidant activity of flavonoids from Carissa bispinosa, Ficus sycomorus, and Grewia bicolar fruits

BACKGROUND: Carissa bispinosa, Ficus sycomorus, and Grewia bicolar are edible fruit plants that grow in the wild. The plants produce yellow-, red-, and purple-colored fruits and thus can be good sources of flavonoids for fighting oxidative reactions in humans, food, and the pharmaceutical industry. The present study aimed at isolating flavonoids from C.bispinosa, F. sycomorus, and G. bicolar fruits and determining their antioxidant activity using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and 2, 2-azino-bis 3-ethylbenz-thiaz-oline-6-sulfonic acid (ABTS) model radical assays. METHODS: Analytical and preparative thin-layer chromatography was used to isolate flavonoids from the fruits using methanol/chloroform/hexane (7:2:1,v/v/v) as a mobile phase system. The ABTS and DPPH radical scavenging methods were used to test for the antioxidant activity of the samples, using quercetin and catechin as reference standards. RESULTS:Thin-layer chromatographic profiling revealed two different types of flavonoids from each plant.C. bispinosa yielded two flavonoid bands, Rfvalues 0.11 and 0.38;G. bicolaryielded two flavonoid bands,Rfvalues 0.63 and 0.81; andF.sycomorus also yielded two types of flavonoids, Rfvalues 0.094 and 0.81. All the extracted flavonoids exhibited significant antioxidant activity of over 80% at a concentration of 200 mg/L. The order of radical scavenging activity for the 200-mg/Lsamples is G. bicolar Rf(0.81) >C. bispinosa Rf(0.113) >F. sycomorus Rf(0.094) >F. sycomorus Rf(0.047) >C. bispinosa Rf(0.38) >G. bicolar Rf(0.63).G. bicolar(Rf= 0.81) exhibited antioxidant activitythat was superior to that of catechin. CONCLUSION:The present study results show that C. bispinosa,F. sycomorus,and G. bicolar contain different flavonoid types with significant antioxidant activity of over 80% at a concentration of 200 mg/L. Therefore, the fruits can be used as a source of natural antioxidants which can be used as nutraceuticals to promote health, as preservatives to delay peroxidation of foods, and as flavoring for packed foods.

Speciation and persistence of doxycycline in the aquatic environment: Characterization in terms of steady state kinetics.

The aim of the present work was to establish the kinetics for the degradation of doxycycline in the aquatic environment with a view to arriving at a kinetic model that can be used to predict the persistence of antibiotic with confidence. The degradation of doxycycline in both water and sediment phases of aquatic microcosm experiments, as well as in distilled water control experiments, was studied over a period of 90 days. An initial 21% loss due to adsorption by the sediment was observed in the microcosm experiment soon after charging. Biphasic zero-order linear rates of degradation, attributed to microbial degradation of the free and sediment or colloidal particle-adsorbed antibiotic, were observed for both water phase (2.3 × 10(-2) and 4.5 × 10(-3) µgg(-1) day(-1)) and sediment phase (7.9 × 10(-3) and 1.5 × 10(-3) µgg(-1) day(-1)) of the microcosm experiment. The covered distilled water control experiment exhibited a monophasic zero-order linear rate (1.9 × 10(-3) µgg(-1) day(-1)) attributed to hydrolysis, while the distilled water experiment exposed to natural light exhibited biphasic liner rates attributed to a combination of hydrolysis and photolysis (2.9 × 10(-3) µgg(-1) day(-1)) and to microbial degradation (9.8 × 10(-3) µgg(-1) day(-1)). A kinetic model that takes into account hydrolysis, photolysis, microbial degradation as well as sorption/desorption by colloidal and sediment particles is presented to account for the observed zero-order kinetics. The implications of the observed kinetics on the persistence of doxycycline in the aquatic environment are discussed.