Pummelo Juice Research Articles

CDNA-AFLP analysis reveals altered gene expression profiles involved in juice sac<italic/> granulation in pummelo (<i>Citrus grandis</i>)

Citrus fruits produced in China are often affected by granulation. Granulation is an altered physiological state of citrus fruits occurring usually before harvest but whose underlying mechanisms remain elusive. In this study, cDNA-AFLP technology enabled the identification of 116 granulation-associated genes in pummelo (<italic>C. grandis</italic>) juice sacs. Differentially expressed transcript-derived fragments (TDFs) were shown to be mainly involved in biological regulation and signal transduction, carbohydrate and energy metabolism, nucleic acid, protein metabolism, stress responses, and cell metabolism. Therefore, granulation in pummelo juice sacs seems to involve the following several alterations: (1) changes in hormone levels; (2) activation of metabolic pathways related to ATP and sugar synthesis to produce more energy; (3) nucleic acid accumulation and increased protein degradation; (4) activation of stress-responsive metabolic pathways; (5) accelerated juice sac senescence. Our findings provide an overview of differential responses occurring at the transcriptional level in granulated juice sacs, thus revealing new insights into the adaptive mechanisms underlying this altered physiological state in ‘Guanximiyou’ pummelo (<italic>C. grandis</italic>) juice sacs.

INTERACTION OF SILDENAFIL WITH HERBAL SUPPLEMENTS: A REVIEW

Erectile dysfunction (ED) is defined as a man's inability to achieve or maintain an erection long enough to complete sexual activity. Sildenafil (SILD) is a drug that is used to treat ED all over the world. In this review article, the interactions between SILD and herbal supplements recorded in the literature were summarized using the Medline database (via PubMed) and the key-words: Sildenafil, herbal supplements, and interactions. In the present review article, pharmacokinetic (PK) and pharmacodynamic (PD) interactions were reported during co-administration of herbal supplements with SILD. Reduction in SILD bioavailability was found as a result of interaction of SILD with Horny goat weed, Thai ginseng, Arugula, Black seed, Garden cress, Fenugreek, and Pummelo juice in human and/or animal models. Meanwhile, Citrus lemon juice has not significantly altered the PK of SILD. Also, PD interactions were found as a result of the interaction of Curcumin, Yohimbine, and Pomegranate juice in human and rat models. Healthcare professionals should be aware of this potential and researchers should strive to fill the numerous gaps in our present understanding of this problem.

Biochemical profiling of aroma and flavonoid compounds in certain genotypes of pummelo

Pummelo fruit volatile compounds are mainly comprised of esters, alcohols, aldehydes, ketones, lactones, hydrocarbons, terpenoids and acids. A total of 50 volatile aroma compounds were identified in pummelo juice which includes 9 hydrocarbons, 10 monoterpenoids, 20 sesquiterpenoids, 9 alcohols, 2 aldehydes and ketones. Limonene was the most abundant compound, representing 0.750 to 49.331 per cent of the total aroma volatiles identified in the juice of pummelo. Among flavonoids 12 compounds identified, Naringenin was found to be high followed by catechin and other compounds. Naringenin levels play an important role in determining the bitterness of pummelo and limonene contributes for the pleasant orange flavour of the juice. Among all the accessions observed, the pink pulp accession 22(4) had high amount of naringenin (601.66 ng/ml) and the low level (100.02ng/ml) was recorded in white pulp accession 20(1) which may be useful as a parent for development of less bitter pummelo.

Fruit characteristics, soluble sugar compositions and transcriptome analysis during the development of Citrus maxima “seedless”, and identification of SUS and INV genes involved in sucrose degradation

Citrus maxima “seedless” is originally from Malaysia, and now is widely cultivated in Hainan province, China. The essential features of this cultivar are thin skin, green epicarp and seedless at the ripening stage. Here, using C. maxima “seedless” as experimental material, we investigated the physical and inclusion indicators, and found the accumulation of storage compounds during 120–210 DAF leading to inconsistent increase between volume and weight. Component analysis of soluble sugar indicated that arabinose and xylose have a high content in early development of pummelo juice sacs (PJS), whereas fructose, glucose and sucrose show a significant increase during PJS maturation. To clarify a global overview of the gene expressing profiles, the PJSs from four periods (60, 120, 180 and 240 DAF) were selected for comparative transcriptome analysis. The resulting 8275 unigenes showed differential expression during PJS development. Also, the stability of 11 housekeeping genes were evaluated by geNorm method, resulting in a set of five genes (UBC, ACT, OR23, DWA2 and CYP21D) used as control for normalization of gene expression. Based on transcriptome data, 5 sucrose synthases (SUSs) and 10 invertases (INVs) were identified to be involved in sucrose degradation. Importantly, SUS4 may be responsible for arabinose and xylose biosynthesis to form the cell wall in early development, while SUS3 and VIN2 may be important in the accumulation of soluble hexose leading to cell expansion through an osmotic-independent pathway in late development. The information provides valuable metabolite and genetic resources in C. maxima “seedless”, and is important for achieving high fruit yield and quality.

Determination of citrus juice coumarins, furanocoumarins and methoxylated flavones using solid phase extraction and HPLC with photodiode array and fluorescence detection

A synergistic combination of analytical techniques was developed for the simultaneous determination of the three most biologically active chemical families in citrus juices: methoxylated flavones, coumarins, and furanocoumarins. No rapid methodology has been available to determine them together. A solid phase extraction concentrated these groups and a ternary reverse phase HPLC gradient completely resolved them from other juice components. Two coumarins, isomeranzin and osthole, were identified in a sweet orange (C. sinensis) cultivar, Changyecheng, for the first time. Pummelo juice was characterized by coumarin and furanocoumarin epoxides such as meranzin and epoxybergamottin. No epoxides were observed in the more acidic juices. Added furanocoumarin epoxides hydrolyzed rapidly in the most acidic juices. The ratios of the UV peak areas at 320 nm to the fluorescence emission peaks as well as the ratio of fluorescence emission peaks at 450–400 nm could be used to identify chromatographic peaks.

Volatile Composition in Two Pummelo Cultivars (Citrus grandis L. Osbeck) from Different Cultivation Regions in China.

This study investigated the composition of volatile compounds in two pummelo cultivars, including ‘Shatian’ and ‘Guanxi’, cultivated in different regions of China with the aim of studying the effect of cultivar and cultivation condition on biosynthesis of volatile compounds in pummelo. Volatile compounds were extracted from pummelo juice using head-space microextraction and then analyzed using gas chromatography coupled with mass spectrometry. Results showed that a total of 49 volatile compounds was detected in the study, including 11 aldehydes, 7 alcohols, 3 ketones, 7 esters, 19 terpenes and 2 other volatiles. The ‘Guanxi’ pummelo cultivar possessed a more complex composition of volatile compounds compared with the ‘Shatian’ cultivar. Meanwhile, the volatile compounds appeared to exhibit a higher concentration in the ‘Guanxi’ cultivar samples than the ‘Shatian’ cultivar. Cluster analysis revealed that the ‘Guanxi’ cultivar samples from the different regions were grouped together, whereas the ‘Shatian’ cultivar samples were assembled. Principal component analysis showed that an obvious separation was observed between the ‘Guanxi’ and ‘Shatian’ cultivar. However, the ‘Shatian-SC15’ was significantly separated from the other ‘Shatian’ cultivar samples. These indicated that cultivar genotype was the primary factor that determined the volatile profile of the pummelo cultivar. Cultivation region might affect the biosynthesis of volatile compounds, resulting in the differentiation of the volatile composition in each pummelo cultivar.

Efficacy of various techniques on biochemical characteristics and bitterness of pummelo juice.

The consumer acceptability of pummelo juice is affected badly due to the presence of bitter principles in it. Therefore in order to avoid such bitterness development, the extracted juice from pummelo was subjected to five different treatments like juice diffused into syrup (70°Brix), lye peeling of segments in boiling NaOH for 2-3min, increasing the pH of juice, hot water treatment (50°C) prior to peeling for 20min and without any treatment (control) for suppressing the development of bitterness in the juice. Based on bio-chemical analysis, diffusion of juice into syrup (70°Brix) showed better result as compared to other treatments. The maximum amount of TSS was found in juice diffused into syrup (i. e. 45, 30 and 15°Brix) along with highest TSS/acid ratio (92.21, 49.87 and 17.53). Higher amount of acidity was observed in pH adjusted samples with 4.25, 4.50 and 4.75 respectively. However, control samples showed higher amount of ascorbic acid (73.97mg/100ml juice) content followed by pH adjusted samples. The highest organoleptic score for taste (8.00), colour (8.83), aroma (8.66), overall acceptability (7.88) and extent of debittering (7.50) were recorded in juice diffused into syrup 70°Brix and achieved final TSS of juice at 45, 30 and 15°Brix respectively. Moreover, the above treatment (juice diffused into syrup 70°Brix) showed promising low cost and easy to adopt technique of debittering in respect of extent of debittering and maintaining sensory quality during storage of pummel juice.

Pectinase and naringinase help to improve juice production and quality from pummelo (Citrus grandis) fruit

Pectinase and naringinase were investigated for improving the production of pummelo juice by increasing the juice yield and eliminating juice bitterness. Compared to a control, the enzymatic treatment significantly (p<0.05) increased the juice yield, soluble pectin and total soluble solid (TSS) contents, and the clarity, while decreasing the concentrations of the bitter chemicals naringin, limonin, and nomilin. A combined processing treatment of peeling and enzymatic hydrolyses using 5U/g of pectinase and 0.4 U/g of naringinase at 50oC for 60 min resulted in a juice yield of 42.3%, a TSS content of 11.4oBx, a titrable acidity (TA) of 0.96%, a vitamin C concentration of 38.4 mg/100 mL, and concentrations of naringin, limonin, and nomilin of 42.4 μg/mL, 33.5 μg/mL, and 13.3 μg/mL, respectively. The enzymatic method was effective and practical for production of high quantity pummelo juice.

Effects of granulation on organic acid metabolism and its relation to mineral elements in Citrus grandis juice sacs

We investigated the effects of granulation on organic acid metabolism and its relation to mineral elements in ‘Guanximiyou’ pummelo (Citrus grandis) juice sacs. Granulated juice sacs had decreased concentrations of citrate and isocitrate, thus lowering juice sac acidity. By contrast, malate concentration was higher in granulated juice sacs than in normal ones. The reduction in citrate concentration might be caused by increased degradation, as indicated by enhanced aconitase activity, whilst the increase in malate concentration might be caused by increased biosynthesis, as indicated by enhanced phosphoenolpyruvate carboxylase (PEPC). Real time quantitative reverse transcription PCR (qRT-PCR) analysis showed that the activities of most acid-metabolizing enzymes were regulated at the transcriptional level, whilst post-translational modifications might influence the PEPC activity. Granulation led to increased accumulation of mineral elements (especially phosphorus, magnesium, sulphur, zinc and copper) in juice sacs, which might be involved in the incidence of granulation in pummelo fruits.

Determination of Bioactive Compounds in the Juice of Pummelo (Citrus grandis Osbeck)

The juice of pummelo (Citrus grandis Osbeck) was analyzed to determine its composition of flavonoids, polymethoxyflavones, coumarins and psoralens. The analyses were carried out by HPLC using columns packed with small diameter Fused-Core C18 particles to achieve high resolution in short analysis time. In addition, the profile of the native carotenoids present in the juice was determined using a C30 column. Identification of flavonoids was achieved by MS with ESI in negative mode; the MS acquisition of oxygenated heterocyclic compounds was performed in positive APCI; carotenoids were detected with a PDA detector. Nineteen native carotenoids were determined in pummelo juice for the first time. The composition of this juice is also discussed in comparison with other Citrus juices, especially grapefruit.

Development of a cost-effective, palatable and shelf-stable blended beverage of pummelo (Citrus grandisLinn.)

Introduction. Natural beverages face strong competition from synthetic drinks in the open market.Creation of diversity in natural products is a key strategy to withstand this com- petition. Pummelo (Citrus grandis Linn.) is one such potential fruit which could be exploited on a commercial scale if processed properly. The bitterness of pummelo juice is a serious han- dicap in its utilization. The present study aimed at preparation of a cost-effective, palatable blended beverage of pummelo. Materials and methods. To overcome this problem, pummelo was blended with mango ginger and kokum juice in the ratio of (65:30:5) for the preparation of syrup. The product was stored for 120 days in ambient conditions of storage and analyzed for changes in its physicochemical constituents. Results and discussion. Total soluble solids and total sugar increased during storage, while titratable acidity and ascorbic acid content decreased slightly during storage. Organoleptically, the best recipe was 25% juice, 70 °Brix total soluble solids and 1.5% acidity with a score of 6.3 out of 7.0 for overall acceptability. Mango ginger juice suppressed the bitter aftertaste of pummelo juice and imparted its characteristic taste andflavortotheproduct.Theproductwasshelf-stableandhadimportantmedicinalconstituents in it. The (total revenue / total cost) ratio of the product was 2.90. India / Citrus grandis / Curcuma amada / Garcinia indica / beverages / fruit juices / fruit syrups / profitability / flavor / quality

Effect of Starch-Based Edible Coatings on Quality of Minimally Processed Pummelo (Citrus maxima Merr.)

A study on the effect of starch-based edible coatings on shelf life and quality of minimally processed pummelo was conducted during storage at 4°C for 21 days. Starch-based coatings were developed from two types of native starches (rice and cassava) and mixed with two concentrations of pummelo juice (5 and 10% by volume) as anti-browning agents. It was found that the property of edible coating from cassava starch had a lower water vapor transmission rate of 785 g/m2/day compared with the coating modified from rice starch in which the water vapor transmission rate was 1,230 g/m2/day. Results showed that coated minimally processed pummelo had a lower weight loss of 4.8–7.7% compared to the control (non-coated minimally processed pummelo). Total sugars of minimally processed pummelo coated with rice and cassava starch increased. Titratable acidity and vitamin C content of minimally processed pummelo coated with rice and cassava starch was low compared to the control. The hue angle of surface color of minimally processed pummelo coated with the two starches did not differ from the control.

Karakter morfologi dan kimia 18 kultivar Pamelo (citrus maxima (burm.) Merr.) Berbiji dan tanpa biji

The objective of this study was to evaluate morphological and chemical characteristics of seeded and seedless pummelo fruit. The study was carried out during April 2009 to July 2010. The pummelo fruits were harvested from the production center of Sumedang, Pati, Kudus, Magetan, Bireun (Aceh) and Pangkep (South Sulawesi). Some of seeded cultivars have spherical and ellipsoid form, while the seedless one shown pyriform shape. The edible portion of the fruits (juice vesicles) mainly affected by peel thickness and fruit shape. The edible portion of seedless cultivars (57.22%) were not sigificantly different with seeded (57.07%) and potentially seedless cultivars (59.35%). Generally fruit taste of seedless cultivars were sweet to sweet-bitter, meanwhile seeded and potentially seedless pummelo cultivars have sour-sweet. Pummelo juice taste was affected by TSS (total soluble solids), TA (titratable acidity), TSS/TA ratio and naringin content. Seedless pummelo cultivars have higher pH, TSS, TSS/TA ratio, vitamin C and naringin, but lower in TA content than seeded and potentially seedless fruit juice. ‘Jawa 1’ and ‘Bali Merah 2’ pummelos can be further developed as seedless superior cultivars. Keywords: fruit shape, edible portion, TSS/TA, naringin, vitamin C

The effects of pummelo juice on pharmacokinetics of sildenafil in healthy adult male Jordanian volunteers

The main purpose of this work was to investigate the effect of pummelo juice on the pharmacokinetics of sildenafil after oral administration. This was a comparative, randomized, two-period, two-treatment, two-sequence, single dose, crossover study investigating the effect of pummelo juice on the pharmacokinetics of sildenafil citrate tablets (equivalent to 50 mg sildenafil) in healthy male participants under fasting conditions compared with water as a control. Six healthy normal adult males were administered 50 mg sildenafil with pummelo juice or water at two different periods in a crossover study. Study results showed that pummelo juice reduced the rate and extent of sildenafil bioavailability to around 60% [maximum plasma concentration (C(max)); from 212.44 ng/ml to 134.07 ng/ml, 90% confidence interval (90% CI) 44.70-89.11, and area under the plasma concentration time curve from zero to infinity (AUC(infinity)); from 564.51 ng.hr/ml to 336.87 ng.hr/ml, 90% CI 39.17-90.92]. This interaction was opposite to that expected and is speculated to be due to either an effect on transporters or a physicochemical interaction between sildenafil and some components of the juice. Patients should be advised not to drink pummelo juice before or immediately after taking sildenafil.

Modelling of rheological behaviour of pummelo juice concentrates using master-curve

The rheological behaviour of freeze-dried-concentrated pummelo juice was modelled to investigate the effects of temperature and concentration on its fluid type and viscosity using a rotational viscometer at shear rates ranging from 1 to 400 s −1. The effect of concentration measured by its total soluble solids content resulted in the juice concentrates behaving towards shear thinning or pseudoplastic behaviour with flow behaviour index values, n < 1. Temperature increase from 6 to 75 °C produced a reversing effect of the shear thinning behaviour from the increase of n values at all three investigated concentrations, 20, 30 and 50 °Brix. The consistency coefficient decreases with temperature but increases with total soluble solid contents. Modelling the rheological behaviour of pummelo juice concentrates using the master-curve yielded results over a range of temperature to overlap on a single line, which allows generalisation of flow behaviour and characteristics. The master-curve plots confirmed that the juice viscosity and pseudoplasticity increase with concentration with high regression coefficients, R 2 > 0.98.

Prediction of Physicochemical Properties of Pummelo Juice Concentrates as a Function of Temperature and Concentration

The properties of pummelo juice were studied by measuring its chemical and physical composition. Pummelo fruit juice was freeze-concentrated to a concentration varying from 10 to 50 °Brix for investigation at temperature ranging from 6 to 75 °C. The fresh pummelo juice compositions in terms of moisture content, ash, fat, protein, fibre, carbohydrates, and vitamin C are comparable to existing literature. The water activity, pH and acidity were predictable linearly by its concentration measured in °Brix. The density of pummelo juice was well-predicted using linear regressions with a single parameter (i.e., concentration), giving R2&gt;0.983 and with a temperature at R2&gt;0.921. The density of pummelo juice showed stronger dependence on its concentration than on the temperature. With multiple linear regressions, the density could be predicted by the equation, with an R2 of 0.9877. As such, these predictions are useful in the juice processing industry as densities variant by concentration and temperature are important during the pasteurization process.

Rheological Properties of Diluted Pummelo Juice as Affected by Three Different Concentrations

Pummelo is a popular fruit that has great potential to be commercialized. The physico-chemical characterization of pummelo juice such as proximate analysis, pH, moisture content, protein, fat, carbohydrate, ash and fibre contents are investigated. The rheological characterization of pummelo juice was modeled by several models, such as Bingham, Power Law and Casson models. Regression analysis shows good agreements for all three models applied in this study. Pummelo juice exhibits pseudoplastic behaviour under the conditions tested, as indicated by flow behaviour indices (n) ranging from 0.1 to 0.9 from power law model, indicating strong shear-thinning behaviour.

Antioxidant Content and Free Radical Scavenging Ability of Fresh Red Pummelo [Citrus grandis (L.) Osbeck] Juice and Freeze-Dried Products

The antioxidative phytochemicals in various fruits and vegetables are widely recognized for their role in scavenging free radicals, which are involved in the etiology of many chronic diseases. Colored fruits are especially considered a quality trait that correlates with their nutritional values and health benefits. The specific aim of this study was to investigate the antioxidants in the juice and freeze-dried flesh and peel of red pummelo and their ability to scavenge free radicals and compare them with those in white pummelo juice. The total phenolic content of red pummelo juice extracted by methanol (8.3 mg/mL) was found to be significantly higher than that of white pummelo juice (5.6 mg/mL). The carotenoid content of red pummelo juice was also significantly higher than that in white pummelo juice. The contents of vitamin C and delta-tocopherol in red pummelo juice were 472 and 0.35 mug/mL, respectively. The ability of the antioxidants found in red pummelo juice to scavenge radicals were found by methanol extraction to approximate that of BHA and vitamin C with a rapid rate in a kinetic model. The ability of methanol extracts of freeze-dried peel and flesh from red pummelo to scavenge these radicals was 20-40% that of BHA and vitamin C effects. Fresh red pummelo juice is an excellent source of antioxidant compounds and exhibited great efficiency in scavenging different forms of free radicals including DPPH, superoxide anion, and hydrogen peroxide radicals.

Differences in the Carotenoid Content of Ordinary Citrus and Lycopene-Accumulating Mutants

High-performance liquid chromatography, coupled with photodiode array detection, was used to analyze the carotenoid composition of peel and juice vesicle tissues of ordinary and lycopene-accumulating mutants (referred to as red mutants in this article) of orange, pummelo, and grapefruit. Thirty-six major carotenoids, including some cis-trans isomers, were separated on a C30 reversed phase column, and 23 of them were identified on the basis of retention times and spectral characteristics with authentic standards. Carotenoid profiles varied with tissue types, citrus species, and mutations. beta-Citraurin occurred in the peel of oranges but not in juice vesicles, whereas the reverse was found for violaxanthin, 9-cis-violaxanthin, and luteoxanthin. The diversity of carotenoids in peel and juice vesicle tissues and the fact that there was over 250 times higher content of total carotenoids in peels of Yuhuan pummelo than juice vesicles suggested that the biosynthesis of carotenoids in these two tissues was independent and exchange of carotenoids between the tissues was not likely. Lutein was observed in peels of pummelos and grapefruits and juice vesicles of ordinary pummelo but not in orange tissues. Accumulation of lycopene and beta-carotene was observed in red mutant citrus, except for the peel of Cara Cara red orange. Additionally, phytoene accumulated in all tissues except for the peel of Chuzhou Early Red pummelo. No obvious change in the total content of xanthophylls was observed in the Cara Cara red orange. Ordinary grapefruit (Marsh) tissues and pummelo (Yuhuan) juice vesicles were almost devoid of carotenoids, and in red mutants, the content of total carotenoids increased dramatically up to 790-fold. The different changes in carotenoid content and profiles in mutant(s) of different citrus species suggest that the underlying mechanisms for the mutations might be different.

Limonoids in Pummelos [Citrus grandis (L.) Osbeck

ABSTRACTJuice and seeds from 16 cultivars of mature pummelo fruits were analyzed for limonoid content. Pummelo juice contained an average of 18 ppm limonin and 29 ppm total limonoid glucosides. Compared to other juices, ptmnnelo contained very high concentrations of limonin and very low concentrations of limonoid glucosides. Limonin, nomilin, obacunone and trace amounts of deacetyhromilin were found in pummelo seeds. The 17–β‐D‐glucopyranoside derivatives (glucosides) of nomilin, nomilinic acid and obacunone were also present. Total limonoid aglycone concentration in the seeds ranged from 773 ppm to 9,900 ppm and total limonoid glucosides ranged from 130 ppm to 1,912 ppm.