Retinal Degeneration Progression Changes Lentiviral Vector Cell Targeting in the Retina

In normal mice, the lentiviral vector (LV) is very efficient to target the RPE cells, but transduces retinal neurons well only during development. In the present study, the tropism of LV has been investigated in the degenerating retina of mice, knowing that the retina structure changes during degeneration. We postulated that the viral transduction would be increased by the alteration of the outer limiting membrane (OLM). Two different LV pseudotypes were tested using the VSVG and the Mokola envelopes, as well as two animal models of retinal degeneration: light-damaged Balb-C and Rhodopsin knockout (Rho-/-) mice. After light damage, the OLM is altered and no significant increase of the number of transduced photoreceptors can be obtained with a LV-VSVG-Rhop-GFP vector. In the Rho-/- mice, an alteration of the OLM was also observed, but the possibility of transducing photoreceptors was decreased, probably by ongoing gliosis. The use of a ubiquitous promoter allows better photoreceptor transduction, suggesting that photoreceptor-specific promoter activity changes during late stages of photoreceptor degeneration. However, the number of targeted photoreceptors remains low. In contrast, LV pseudotyped with the Mokola envelope allows a wide dispersion of the vector into the retina (corresponding to the injection bleb) with preferential targeting of Müller cells, a situation which does not occur in the wild-type retina. Mokola-pseudotyped lentiviral vectors may serve to engineer these glial cells to deliver secreted therapeutic factors to a diseased area of the retina

Study of phenolic composition of olive fruits: validation of a simple and fast HPLC-UV method

A high-performance liquid chromatography (HPLC) method endowed with a gradient elution and a UV detection system was established and validated for the determination of phenolic acids, phenolic alcohols, hydroxycinnamic acid derivatives, flavonoids, secoiridoids and lignans during olive (Olea europaea L.) fruit development (green, purple and black olives). Within the test range, the calibration curves exposed a good linear regression (R 2>0.9995). Detection limits ranged between 0.63 and 13.43 mg/L for the detected phenolic compounds. The presented method yielded satisfactory repeatability in terms of retention times and average concentrations of phenolic compounds (RSD < 0.3%). Verbascoside was established as the major phenolic compound in black olives. Oleuropein was established as the dominating phenolic compound in green olives, and its level decreased during maturation. Additionally, this research is the first to experimentally evidence that the flavone luteolin-7-rutinoside is the predominant flavonoid glucoside in black olives, showing the most significant variation with fruit development. The above results validate the method for an easy and fast determination of different classes of phenolic compounds present in olive fruits

Modification of pomological characteristics and flavor components of fruits and virgin olive oil following wastewater irrigation and soil tillage

BACKGROUND The experiment was carried out on olive trees cv. Chemlali, during two successive years (2013/2014). Two irrigation treatments (IT: Trees irrigated with wastewater; TRC: Trees grown under rainfed condition) were combined with two tillage practices (TTS: Trees grown in tilled soil; TNTS: Trees grown in non-tilled soil). RESULTS The results of the study showed that WW irrigation combined with soil tillage improved the pomological characteristics of olive fruits. The tree yield increase was substantial for IT and TTS. However, most of the identified phenolic compounds, especially oleuropein, mainly accumulated in olive fruits of the TC block (TNTS + TRC), suggesting a marked improvement in the nutritional value of these fruits. Moreover, fruits of TNTS had high contents of sugar compounds, required for the synthesis of the fruit storage material. The study also showed that the agronomic practices affected the amounts of some aromatic compounds responsible for the distinctive flavor notes of olive oil. CONCLUSION Hence, agronomic practices may affect considerably the commercial and nutritional values and the sensorial quality of the commodities

Modification of Phenolic Compounds and Volatile Profiles of Chemlali Variety Olive Oil in Response to Foliar Biofertilization

The main objective of this work was to studythe effects of foliar biofertilizers on individual volatile pro-files and phenolic compounds of olive oil (Olea europaeaL. cv. Chemlali). Three foliar biofertilizers were used intwo successive application seasons: T1 (rich in nitrogen,phosphorus and potassium); T2 (rich in calcium); and T3(application of both T1 and T2). Results showed that foliarfertilization with T2 increased the phenolic compound con-tents (e.g., oleuropein aglycone and decarboxymethyl lig-stroside aglycone) of Chemlali olive oil. It also enhancedthe levels of many volatile compounds responsible for thegoodflavor of olive oil such as hexanal. However,T1-tested fertilizer led to a significant decrease in the con-tent of phenolic compounds, although they seemed toimprove significantly the levels of the majority of volatilecompounds, especially hexanal. Based on these results, asignificant relationship between plant nutrition and qualityof oil was observed. Our results demonstrated a potentialpositive influence on the concentration of sensory qualitycompounds under T2 (Ca2+-based fertilizer). This resultshould be considered in the design of foliar nutrient appli-cation management strategies for olive trees

Modification of Phenolic Compounds and Volatile Profiles of Chemlali Variety Olive Oil in Response to Foliar Biofertilization

The main objective of this work was to studythe effects of foliar biofertilizers on individual volatile pro-files and phenolic compounds of olive oil (Olea europaeaL. cv. Chemlali). Three foliar biofertilizers were used intwo successive application seasons: T1 (rich in nitrogen,phosphorus and potassium); T2 (rich in calcium); and T3(application of both T1 and T2). Results showed that foliarfertilization with T2 increased the phenolic compound con-tents (e.g., oleuropein aglycone and decarboxymethyl lig-stroside aglycone) of Chemlali olive oil. It also enhancedthe levels of many volatile compounds responsible for thegoodflavor of olive oil such as hexanal. However,T1-tested fertilizer led to a significant decrease in the con-tent of phenolic compounds, although they seemed toimprove significantly the levels of the majority of volatilecompounds, especially hexanal. Based on these results, asignificant relationship between plant nutrition and qualityof oil was observed. Our results demonstrated a potentialpositive influence on the concentration of sensory qualitycompounds under T2 (Ca2+-based fertilizer). This resultshould be considered in the design of foliar nutrient appli-cation management strategies for olive trees