A Critical Review on Physiological Changes during Growth Maturation and Ripening of Citrus Fruits

Citrus is one of the major fruit crops in the world and widely recognized by their nutritional, organoleptic and health-related benefits of fresh fruit. The genetic diversity among the genus and independent changes in peel and pulp, make the definition of standard maturity indexes of fruit quality. Commercial maturity indexes in the citrus industry are usually based on peel coloration, soluble solids, pH but their relevance may differ among varieties and the specific requirements of the markets. Citrus fruits are excellent source of many phytochemical, including ascorbic acid, antioxidant, tannin, etc., which greatly contribute to the health-related benefits of citrus fruits. Criteria and definition of the main maturity indexes for citrus fruit worldwide are described, as well as changes during fruit maturation in key components affecting organoleptic and nutritional properties. Citrus fruits were analyzed at different maturity stages. This review is aimed to characterize the physiological maturity of the fruit across the different developmental stage which has not been well reported in literature till now.

Occurrence of citrus brown and black spot diseases and their control using pre-harvest approaches

Mild brown and black spot diseases symptoms were detected on citrus varieties, Valencia and Navel fruits during season 2018 in some citrus orchards at North Egypt. Collected diseased fruit samples revealed isolation of Alternaria alternata and Phyllosticta citricarpa (McAlpine) van der Aa. Some organic acids, salts and Saccharomyces cerevisiae were evaluated against the diseases incidents in vitro and in vivo. Complete growth inhibition was recorded for fungi tested at 2g/L of salicylic acid, Potassium dihydrogen phosphate, Tri-Sodium polyphosphate and 2.5 g/L of S. cerevisiae. All pre-harvest treated Valencia trees, inoculated fruits revealed no diseases symptoms up to 10 days of storage period. Meanwhile, S. cerevisiae and salicylic acid treatments had extended protective effect up to 20 days. Control strategy through spraying Valencia orange trees with yeast or some organic acids and salts as pre-harvest approaches should be taken in consideration especially these diseases began to occur in North region of Egypt.

Actividad antioxidante in vitro y toxicidad de extractos hidroalcohólicos de hojas de Citrus spp. (Rutaceae) / Antioxidant activity in vitro and toxicity of hydroalcoholic extracts from Citrus spp. (Rutaceae) leaves

Introducción: los cítricos constituyen un género de plantas rico en contenido de fenoles y flavonoides, metabolitos secundarios que debido a su efecto antioxidante y baja toxicidad, han recibido en los últimos años mucha atención como potenciales fármacos. Objetivos: determinar la actividad antioxidante in vitro y la toxicidad frente a Artemia salina L. de extractos hidroalcohólicos de hojas de Citrus aurantium L. var. sinensis L.; Citrus aurantium L.; Citrus aurantiifolia (Christm.) Swingle; Citrus latifolia (Tanaka ex Yu. Tanaka) Tanaka; Citrus reticulata Blanco (Rutaceae). Métodos: los extractos etanólicos y metanólicos se obtuvieron mediante extracción por ultrasonido y se caracterizaron fitoquímicamente; se determinó la concentración total de fenoles y flavonoides. La actividad antioxidante se halló mediante la capacidad atrapadora de radicales libre y el poder reductor. La toxicidad se evaluó mediante el bioensayo de letalidad sobre Artemia salina. Resultados: en los extractos etanólicos se encontró mayor presencia de compuestos químicos que en los extractos metanólicos. La mayor concentración de fenoles totales se obtuvo en el extracto metanólico de Citrus reticulata y de flavonoides totales en el extracto etanólico de Citrus aurantifolia y Citrus reticulata, en ambos solventes. Todos los extractos mostraron actividad antioxidante mediante las 2 pruebas ensayadas. Los extractos presentaron toxicidad moderada frente Artemia salina, siendo el extracto metanólico de Citrus latifolia el de menor toxicidad (LC50 = 464,24 µg/mL). Conclusiones: se evidenció la presencia de fenoles y clases de flavonoides, la actividad antioxidante de los extractos hidroalcohólicos de Citrus spp. y su moderada toxicidad frente a Artemia salina

Introduction: citrus fruits constitute an important source of flavonoids and phenols. The latter are secondary metabolites extensively studied in the last few years on account of their antioxidant effect and low toxicity and of their potentialities as pharmaceuticals. Objectives: to determine the in vitro antioxidant activity and toxicity against Artemia salina of hydroalcoholic extracts obtained from leaves of Citrus aurantium L. var. sinensis L.; Citrus aurantium L.; Citrus aurantiifolia (Christm.) Swingle; Citrus latifolia (Tanaka ex Yu. Tanaka) Tanaka, Citrus reticulata Blanco (Rutaceae). Methods: the ethanol and methanol extracts were obtained by ultrasound-assisted extraction method, and characterized using phytochemistry assays; the total amount of phenols and flavonoids was also determined. The antioxidant activity was estimated by the free radical scavenging activity and reducing power. The toxicity of the extracts was evaluated against Artemia salina. Results: the amount of chemical compounds was higher in ethanol than in methanol extracts. The highest concentration of total phenols was found in methanol extract from Citrus reticulate where that of total flavonoids was seen in the ethanolic extracts from Citrus aurantiifolia and Citrus reticulate, in both solvents. The extracts showed antioxidant activity after the two tests. All the extracts presented moderate toxicity against Artemia salina, being the methanol extract from Citrus latifolia the least toxic (LC50= 464.24 µg/mL). Conclusions: this study showed the existence of phenols and flavonoids, the antioxidant activity of hydroalcoholic extracts from Citrus spp. leaves and their moderate toxicity against Artemia salina

Citrus Fruits Intake and Prostate Cancer Risk: A Quantitative Systematic Review / 예방의학회지

OBJECTIVES: The purpose of this systematic review was to investigate the association between dietary intake of citrus fruits and prostate cancer risk. METHODS: Authors searched electronic databases and the reference lists of publications of diet and prostate cancer studies until August 2007. All of the epidemiological studies that obtained individual data on dietary intake of citrus fruits and presented risk estimates of the association between intake of citrus fruits and risk of prostate cancer were identified and included. Using general variance-based methods, study-specific odds ratios (OR)/ relative risk (RR) and associated confidence interval (CI)/ standard error (SE) for highest versus lowest intake of citrus fruits level were extracted from each paper. RESULTS: Eleven articles including six case-control studies, one nested case-control study and four cohort studies, proved eligible. Overall summary OR using random effect model did not show an association in risk of prostate caner with intake of citrus fruits (summary OR=1.03, 95% CI=0.89-1.19) with large heterogeneity across studies that we were unable to explain (I(2)=67.88%). The summary ORs in case-control studies and cohort studies were 1.10 (95% CI=0.97-1.22) and 1.05 (95% CI=0.96-1.14), respectively. CONCLUSIONS: Pooled results from observational studies did not show an association between intake of citrus fruits and the risk of prostate cancer, although results vary substantially across studies.

The antimicrobial activity of citrus fruit extracts: An in-vitro assay

BACKGROUND: The scarcity of local research on extracts of citrus fruits precludes their use as an alternative medication, particularly in the field of Dermatology.OBJECTIVES: This study aims to determine the antimicrobial activity of citrus fruit extracts and to contribute to existing data supporting the use oi these extracts against superficial bacterial and fungal diseases of the skin.METHODS: Crude ethanolic pulp and/or seed extracts and essential oils of Citrus paradisi(grapefruit), Citrus grandis(pomelo), and Citrofortunella microcarpa(calamansi) were screened for antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans the disc diffusion method. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of C. microcarpapulp extract against S. aureus was then determined using standard dilution susceptibility testing. Thin layer chromatography was used to identify the presence of flavonoids, using naringin as a standard.RESULTS: The widest zones of inhibition against the test organisms were seen with calamansi pulp extract. Susceptibility testing showed that calamansi pulp extract was bacteriostatic for S. aureusup to 12.5 percent dilution. However, no bactericidal effect was observed. Naringin was identified only in the pulp extract of grapefruit.CONCLUSION: In vitro, calamansi pulp extract was shown to be an effective antimicrobial against S. aureus, P. aeruginosa, and C. albicans. Whether or not this has any dermatologic significance awaits further /w-vj'votesting.