Carotenoids in yellow‐ and red‐fleshed papaya (Carica papaya L)

Vitamin A deficiency is a disorder of public health importance in Sri Lanka. A recent national survey revealed that 36% of preschool children in Sri Lanka have vitamin A deficiency (serum retinol <0.2 µg ml^?1). In view of its well‐established association with child morbidity and mortality, this is a reason for concern. One of the main fruits which has been recommended for prevention of vitamin A deficiency in Sri Lanka is papaya (Carica papaya L). In this study the carotenoid profiles of yellow‐ and red‐fleshed papaya were analysed by medium‐pressure liquid chromatography (MPLC) and UV‐vis spectrophotometry. A section of yellow‐fleshed papaya showed small carotenoid globules dispersed all over the cell, whereas in red‐fleshed papaya the carotenoids were accumulated in one large globule. The major carotenoids of yellow‐fleshed papaya were the provitamin A carotenoids β‐carotene (1.4 ± 0.4 µg g^?1 dry weight (DW)) and β‐cryptoxanthin (15.4 ± 3.3 µg g^?1 DW) and the non‐provitamin A carotenoid ζ‐carotene (15.1 ± 3.4 µg g^?1 DW), corresponding theoretically to 1516 ± 342 µg kg^?1 DW mean retinol equivalent (RE). Red‐fleshed papaya contained the provitamin A carotenoids β‐carotene (7.0 ± 0.7 µg g^?1 DW), β‐cryptoxanthin (16.9 ± 2.9 µg g^?1 DW) and β‐carotene‐5,6‐epoxide (2.9 ± 0.6 µg g^?1 DW), and the non‐provitamin A carotenoids lycopene (11.5 ± 1.8 µg g^?1 DW) and ζ‐carotene (9.9 ± 1.1 µg g^?1 DW), corresponding theoretically to 2815 ± 305 µg kg^?1 DW mean RE. Thus the carotenoid profile and organisation of carotenoids in the cell differ in the two varieties of papaya. This study demonstrates that carotenoids can be successfully separated, identified and quantified using the novel technique of MPLC. Copyright © 2003 Society of Chemical Industry     

番木瓜叶不同溶剂提取物的抗氧化性能

以番木瓜叶为研究对象,用水、70%甲醇和70%乙醇对其中活性物质进行了提取。测定了三种试剂提取率、总酚以及总黄酮含量,还对提取物的自由基清除能力、金属离子螯合能力（MCC）和铁离子氧化还原能力（FRAP）进行了研究。结果表明提取得率和总酚含量的大小顺序是:水>70%甲醇>70%乙醇,而总黄酮的含量与此相反。三种提取物都具有良好的DPPH·、ABTS⁺·和·OH自由基清除能力、金属离子螯合能力（MCC）和铁离子氧化/还原能力（FRAP）。综合考虑提取率、活性物质含量和各种抗氧化指标,70%甲醇被选为最合适的番木瓜叶提取试剂。该研究为番木瓜叶在制备天然抗氧化剂方面的应用提供了实验基础,还提高了番木瓜的整体利用价值。      

番木瓜中糖类成分的纯化与鉴定

目的：研究番木瓜果肉的糖类成分,以寻找活性化合物。方法：干燥的番木瓜干经95%乙醇提取,石油醚萃取脱脂后的水相采用聚酰胺、MCI、ODS、ODS-AQ柱层析进行纯化,并通过MS和NMR鉴定。结果：从番木瓜果肉乙醇提取物中分离并鉴定出4个糖的衍生物,分别为乙基α-D-果糖苷(Ⅰ)、乙基β-D-果糖苷(Ⅱ)、苄基β-D-葡萄糖苷(Ⅲ)、2-O-β-D-葡萄糖苷-3,6-二羟乙基-5-苯基-1,4-二氧已基-2-醇(Ⅳ)。     

Anticancer activity of Carica papaya: A review

Carica papaya is widely cultivated in tropical and subtropical countries and is used as food as well as traditional medicine to treat a range of diseases. Increasing anecdotal reports of its effects in cancer treatment and prevention, with many successful cases, have warranted that these pharmacological properties be scientifically validated. A bibliographic search was conducted using the key words “papaya”, “anticancer”, and “antitumor” along with cross‐referencing. No clinical or animal cancer studies were identified and only seven in vitro cell‐culture‐based studies were reported; these indicate that C. papaya extracts may alter the growth of several types of cancer cell lines. However, many studies focused on specific compounds in papaya and reported bioactivity including anticancer effects. This review summarizes the results of extract‐based or specific compound‐based investigations and emphasizes the aspects that warrant future research to explore the bioactives in C. papaya for their anticancer activities.     

番木瓜中皂苷类成分的研究

目的：研究番木瓜果肉的化学成分,寻找活性物质。方法：用85% 乙醇提取,大孔吸附树脂、ODS、MCI 柱层析进行分离,NMR 波谱法鉴定化合物的结构。结果：从番木瓜果肉乙醇提取物中分离到3 种化合物,分别为2β,3β - 二羟基- 乌苏酸(Ⅰ)、3-O- 葡萄糖- 甾苷(Ⅱ)、薯蓣皂苷元-3-O- β -D- 吡喃葡萄糖基(1 → 3)- β -D- 吡喃葡萄糖基(1 → 4)-[α -L- 吡喃鼠李糖基(1 → 2)]- β -D- 吡喃葡萄糖苷(Ⅲ)。     

番木瓜果酒发酵及其抗氧化能力分析

以番木瓜为原料,经破碎、酶解、成分调整后接种葡萄酒活性干酵母,于（22±1） ℃发酵制备番木瓜果酒。研究发酵过程中总糖、还原糖、滴定酸含量与抗氧化能力的变化,明确番木瓜果酒的理化指标与感官品质。结果表明,番木瓜果酒发酵过程中总糖、还原糖含量逐渐降低,滴定酸含量增加,总酚含量、DPPH自由基清除率和亚铁还原能力（FRAP值）降低,pH值变化无规律性。番木瓜果酒酒精度10.7%vol,残糖量4.4 g/L,滴定酸4.5 g/L,总酚含量3.0 g/L,DPPH自由基清除率63.0%,FRAP值2.33 mmol/L,属半干型果酒,抗氧化能力较强,理化与感官品质均符合相关果酒标准要求。     

Isolation and Identification Carpaine in Carica papaya L. Leaf by HPLC-UV Method

The carpaine was isolated from Carica papaya L. leaf, was identified by means of Fourier transform infrared spectroscopy, mass spectrometry, nuclear magnetic resonance, and was determined by HPLC. The powder of dried leaves was macerated and extracted with ethanol/water/HCl (89:10:1 V/V/V) to produce crude alkaloid. The extract was fractionated on a silica gel column chromatography using methanol/chloroform (5:95 v/v) as the eluate. The major fraction was isolated according to R_f values of thin-layer chromatography (TLC) (silica gel, methanol/chloroform [15:85 v/v]) exposed by Dragendroff’s reagent. The extraction procedure, sample preparation, and HPLC conditions were evaluated and optimized. The method was fully validated in terms of accuracy, precision, specificity, and calibration model. Results showed that the developed HPLC method was suitable for the determination of carpaine using a single-point calibration. The calibration model was linear in the concentration range from 0.20 to 1.8 mg/mL. Analysis of different days showed that the method was precise with an average concentration of 0.93 g/kg and relative standard deviation of 0.062%. A recovery of between 97.6 and 100.1% was obtained in a 95% confidence interval indicating that the method was accurate and the content of the carpaine in the powdered Carica papaya leaves was 0.93 g/kg.     

Phenolic and carotenoid profiles of papaya fruit (Carica papaya L.) and their contents under low temperature storage

BACKGROUND: Tropical fruits are rich in phenolic and carotenoid compounds, and these are associated with cultivar, pre‐ and postharvest handling factors. The aim of this work was to identify major phenolics and carotenoids in ‘Maradol’ papaya fruit and to investigate their response to storage temperature. RESULTS: Ferulic acid, caffeic acid and rutin were identified in ‘Maradol’ papaya fruit exocarp as the most abundant phenolic compounds, and lycopene, β‐cryptoxanthin and β‐carotene were identified in mesocarp as the major carotenoids. Ranges of contents of ferulic acid (1.33–1.62 g kg^?1 dry weight), caffeic acid (0.46–0.68 g kg^?1 dw) and rutin (0.10–0.16 g kg^?1 dw) were found in papaya fruit, which tend to decrease during ripening at 25 °C. Lycopene (0.0015 to 0.012 g kg^?1 fresh weight) and β‐cryptoxanthin (0.0031 to 0.0080 g kg^?1 fw) were found in fruits stored at 25 °C, which tend to increase during ripening. No significant differences in β‐carotene or rutin contents were observed in relation to storage temperature. CONCLUSION: Phenolics and carotenoids of ‘Maradol’ papaya were influenced by postharvest storage temperature with exception of β‐carotene and rutin. Ripe papaya stored at 25 °C had more carotenoids than those stored at 1 °C. Low (chilling) temperature (1 °C) negatively affected the content of major carotenoids, except β‐carotene, but preserved or increased ferulic and caffeic acids levels, as compared to high (safe) temperature (25 °C). Copyright © 2010 Society of Chemical Industry     

番木瓜籽蛋白质的提取工艺及其功能性质

以番木瓜籽为原料,经脱脂以酸沉碱溶法提取其中的蛋白质,并研究其乳化、起泡等功能性质。结果表明,最佳的提取工艺条件:料液比1∶40,p H为9.3,温度50℃,碱提时间120 min时最高提取率达到48.53%。番木瓜籽蛋白质的乳化性及稳定性随着蛋白质的浓度升高而升高,在p H3时最小,其乳化性在Na Cl浓度为0.2%时最大,而稳定性呈下降趋势;起泡性及稳定性随蛋白浓度升高而升高,在p H3.0,其起泡性和泡沫稳定性最小,在离子浓度(Na Cl)为0.2 mol/L时,其起泡性和泡沫稳定性最高。可见,此提取工艺效果较好,能将部分番木瓜籽蛋白质提取出来;番木瓜籽分离蛋白质乳化性和起泡性良好,这为番木瓜籽蛋白质的开发利用提供参考依据。      

响应面试验优化番木瓜籽中硫代葡萄糖苷酶解工艺

通过单因素试验和Box-Behnken试验设计响应面分析对番木瓜籽中硫代葡萄糖苷（硫苷）的酶解条件进行优化。通过气相色谱-质谱（gas chromatography-mass spectrometry,GC-MS）联用仪鉴定酶解产物中的异硫氰酸酯种类。结果表明：酶解缓冲液pH值、酶解时间对异硫氰酸酯得率有显著影响,酶解温度影响不显著;得到的最优酶解条件为酶解缓冲液pH 4.8、酶解时间40 min、酶解温度27 ℃,在此条件下异硫氰酸酯得率为13.5‰;GC-MS结果表明,番木瓜籽硫苷酶酶解产物中只含有异硫氰酸苄酯一种异硫氰酸酯。     

Characterization and antioxidant evaluation of phenolic compounds extracted from the protein concentrate and protein isolate produced from pawpaw (Carica papaya Linn.) seeds

In this study, the qualitative and quantitative analysis of the absolute (100%) and aqueous (80%) methanolic extract of Carica papaya Linn processed seed flour samples in terms of their antioxidant properties and their phenolic compounds was investigated. The antioxidant properties were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power, and metal chelating assay methods. The protein isolate exhibited higher radical scavenging activity power as compared to other samples. Ferulic acid, caffeic acid, p-coumaric acid, kaempferol-3-glucoside, p-hydroxybenzoic acid, and quercetin-3-galactoside were phenolic compounds isolated with ferulic acid as high as 0.62 mg/DWg. Carica papaya seed isolates and concentrate demonstrated potent antioxidant activity and could be of nutraceutical importance in the pharmaceutical and food industry.     

Characterisation of odour‐active compounds in papaya (Carica papaya L.) wine

The volatile compounds of papaya wine were isolated by continuous solvent extraction and analysed by gas chromatography‐flame ionization detector and gas chromatography‐mass spectrometry. A total of 118 volatile constituents were detected, and ninety‐seven were positively identified. The composition of papaya wine included fifty‐three esters, twenty‐two alcohols, nine acids, seven phenols and derivatives, seven sulphur compounds, five lactones, five terpenes, three ketones, two aldehydes and five miscellaneous compounds. The aroma‐active areas in the gas chromatogram were screened by application of the aroma extract dilution analysis and by odour activity values. Six odorants were considered as odour‐active volatiles: ethyl octanoate, (E)‐β‐damascenone, 3‐methylbutyl acetate, benzyl isohtiocyanate; ethyl hexanoate and ethyl butanoate.     

Purification and properties of pectinesterase from papaya

Pectinesterase (PE) was partially purified from papaya pulp, and its biochemical properties were studied. The enzyme was eluted in a single peak after DEAE-cellulose and Sephadex G-100 chromatography. The PE had a molecular weight of 53000 and showed an optimum pH of 8.0. Its activity was dependent on an NaCl concentration of 0.2M . The enzyme was heat stable: approximately 80% of the original activity remained after 60 min of heating at 50°C but completely inactivated by incubation at 80°C for 1 min. The activity was linear with time and protein concentration. The maximum reaction in 3 min was found at 60°C and the initial rate increased 9-fold from 20 to 60°C. The estimated K_m was 0.12g litre^?1 with citrus pectin as the substrate. The kinetic study revealed that polygalactur-onic acid is a competitive inhibitor, and a K_i value of 0.07 g litre^?1 was determined. On the basis of this study, papaya PE properties resembled those of pectinesterase from other sources.     

Pectinesterase and Polygalacturonase Activities and Textural Properties of Rubbery Papaya (Carica papaya Linn.)

: Comparisons in color of flesh, pectin composition, pectinesterase (PE), polygalacturonase, cellulase activities, and textural properties of normal green papaya (NGP), rubbery papaya (RP), and normal yellow and ripe papaya (NYRP) were conducted. RP contained about 9.7% pectin with a degree of esterification of 53.1%, while NYRP contained about only 1.2% pectin with a degree of esterification of about 23.4%. PE activity (13.6 unit/g fresh weight) than in RP was significantly lower (18.0 unit/g fresh weight) in NYRP (P < 0.05), whereas polygalacturonase activity (46.9 unit/g fresh weight) in RP was higher (27.0 unit/g FW) than in NYRP. Therefore, in combination with the fact that water extract from RP displayed an inhibitory ratio of 36.0% on papaya PE activity, we suggest the presence of certain substances with strong PE inhibitory activity in RP.     

Antioxidant activity of Smilax excelsa L. leaf extracts

Smilax excelsa L. leaves are used widely in the Black Sea region of Turkey for consumption in the daily diet and in folk medicine for their medicinal properties. In the present study, different antioxidant tests were employed in order to evaluate the antioxidant activities of water, infusion, ethanol and ethyl acetate extracts of S. excelsa leaves. In addition, the results were compared with natural and synthetic antioxidants. The levels of total phenolics, total flavonoids and anthocyanins of the extracts were also determined. The extracts were found to have different levels of antioxidant properties in the test models used. All extracts had good total phenolic and flavonoid contents, inhibited lipid peroxidation, showed radical scavenging and iron-chelating activities. Therefore, the leaves of the plant could be considered as a significant natural antioxidant source.