Influence of an increased NaCl concentration on yield and quality of cherry tomato grown in posidonia (Posidonia oceanica (L) Delile)

Tomato plants cv Naomi were grown in posidonia (Posidonia oceanica (L) Delile) with two NaCl salinity levels in nutrient solution (EC: 3 and 6 dS m^?1) or with the NaCl level 3 dS m^?1, in the most frequently used substrate in soilless systems, eg rockwool, to determine the effect of substrate or EC on yield, contents of minerals, antioxidants with nutritional and health values (vitamin C, lycopene, α‐tocopherol and glutathione) as well as parameters affecting the organoleptic quality in cherry tomato fruits. Total yield was not influenced by substrate, but it was higher with 3 dS m^?1 than 6 dS m^?1 salinity. The yield reduction was compensated by the improvement of dry matter, total soluble solids, vitamin C and α‐tocopherol, while lycopene and glutathione contents were not affected by NaCl. On average, when tomato plants were grown in the presence of the higher NaCl level, the fruit diameter was between 25 and 35 mm (considered optimal for cherry tomato) while, with 3 dS m^?1, it was greater than 35 mm. Copyright © 2004 Society of Chemical Industry     

The effect of sowing date and growth stage on the essential oil composition of three types of parsley (Petroselinum crispum)

Essential oils obtained by simultaneous distillation–extraction (SDE) from leaves, petioles and roots of three types of parsley (turnip‐rooted, plain leaf and curly leaf type), sown on three different dates, were analysed by GC‐MS (gas chromatography–mass spectrometry) analysis. Parsley plants were found to produce mainly β‐phellandrene, 1,3,8‐p‐menthatriene, α‐,p‐dimethylstyrene, myristicin, β‐myrcene and apiole. In some cases α‐ and β‐pinene were also found, whereas β‐elemene was detected, especially in the curly leaf type. The growth stage, plant tissue and date of sowing, as well as the climate conditions, all had a significant effect on the essential oil composition by altering the ratio of the above substances. Copyright © 2004 Society of Chemical Industry     

Effects of soil pH on the uptake of Al,F and other elements by tea plants

Soil extractable Al, F and Zn concentrations decreased whereas extractable Ca, Cu, K, Mg, Na and P concentrations increased when the soil pH was raised from 3 to 6. These trends led to a decrease in growth of tea seedlings as determined by measurements of relative dry weight gain (RDW), relative leaf number gain (RLN) and relative leaf area gain (RLA). Tea seedlings of both ‘large‐leafed’ and ‘small‐leafed’ varieties grown in soils at pH 3 and 3.5 were the tallest and healthiest, while those at pH 6 died after 3 months. The large‐leafed variety showed higher growth rates than the small‐leafed variety. The highest (p < 0.05) amounts of Al and F, 4225 and 430 mg kg^?1 respectively, were found in seedlings under pH 3.5 treatment. When Al and F concentrations in seedlings increased, elements such as Ca, Mg, Na and Zn gently decreased (p < 0.05) whereas P increased. K and Cu were not affected. The results indicated that soil pH values higher than 4 reduced Al and F concentrations in tea plants. © 2001 Society of Chemical Industry     

Rootstock effects on salt tolerance of irrigated field-grown grapevines (Vitis vinifera L. cv. Sultana).: 1. Yield and vigour inter-relationships

Vegetative growth and yield of grapevines grown in the field on their own roots or grafted to a range of rootstocks were investigated under drip irrigation with water of three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five‐year period. Rootstocks were Ramsey, 1103 Paulsen, J17–69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Of measured yield components (bunches per shoot, bunches per vine, weight per bunch, weight per berry and total yield), only weight per berry was significantly reduced by high salinity (3.50 dS/m) in each year of the trial with the exception of Sultana on 1103 Paulsen and R2 in 1991 and Sultana on Ramsey in 1993. Weights of one‐year‐old pruning wood were also reduced by high salinity in all years for own roots and all rootstocks, with the exception of R2. Mean yield values at each salinity level over the five‐year period of the trial were highest for Sultana on Ramsey, 1103 Paulsen and R2. High salinity had no effect on five‐year mean yields of Sultana on Ramsey, 1103 Paulsen and R2. Yield (five‐year means) of Sultana on Ramsey and R2 at 1.75 dS/m were significantly higher than at 0.40 dS/m by 14.6% and 13.4% respectively. In contrast, 5‐year mean yields of Sultana on J17–69, own roots, R1, R3 and R4 at 3.50 dS/m were reduced by 54, 30, 20, 30 and 30% respectively. Yield of Sultana on J17–69, R1 and R4 rootstocks was reduced by 47, 20 and 24% respectively at 1.75 dS/m. When yield was regressed against bunches per vine and weight per bunch for Sultana on own roots and on Ramsey rootstock, bunches per vine was the main determinant of yield, while weight per berry showed a poor correlation with yield at all salinity levels. Rootstock ranking for salt tolerance based on yield at high salinity was the same as rankings for pruning wood weights at high salinity. The same occurred at medium salinity, demonstrating that vigour imparted by the rootstock was a major factor in Sultana salt tolerance as measured by yield. Mean root weighted soil saturation paste electrical conductivities (RWEC_e) (determined from soil saturation paste salinities and root length densities) were in the range 2.0–2.6 dS/m for the low salinity treatment, increasing to approximately 5.4 dS/m with increasing salinity of irrigation water. Yield reduction for own‐rooted vines for each 1.0 dS/m increase in RWEC_e above 2.6 dS/m was 9.3%.     

Modulation of salt (NaCl)‐induced effects on oil composition and fatty acid profile of sunflower (Helianthus annuus L.) by exogenous application of salicylic acid

BACKGROUND: Salicylic acid (SA) is a potential endogenous plant hormone that plays an important role in plant growth and development. Since sunflower yield and its seed oil yield are adversely affected by salinity, in this study the role of SA in modulating salt (NaCl)‐induced effects on various yield and oil characteristics of sunflower was investigated. For this purpose a greenhouse experiment comprising two sunflower hybrid lines (Hysun‐33 and SF‐187), two NaCl levels (0 and 120 mmol L^?1) and four SA levels (0, 100, 200 and 300 mg L^?1) was conducted. RESULTS: Salt stress markedly reduced yield, oil content, linoleic acid and δ‐tocopherol in both sunflower lines, while it increased linolenic acid, palmitic acid, stearic acid and α‐ and γ‐tocopherols. However, increasing levels of foliar‐applied SA resulted in improved achene yield and hundred‐achene weight in both lines. Foliar‐applied SA caused a significant decrease in oil stearic acid and α‐ and γ‐tocopherols in both lines under non‐saline and saline conditions. CONCLUSION: Salt‐induced harmful effects on achene yield and oil characteristics of sunflower could be alleviated by exogenous application of SA. High doses of SA caused a marked increase in sunflower achene oil content as well as some key fatty acids. Copyright © 2010 Society of Chemical Industry     

Effect of pretreatments and drying temperatures on sweet potato flour

Effect of pretreatments with 1 w/v% sodium hydrogen sulphite (NaHSO₃) and 1 w/v% calcium chloride (CaCl₂) and drying temperatures (55, 60 and 65 °C) on sweet potato flour were investigated. Flour treated with CaCl₂ had higher amounts of ascorbic acid and β‐carotene (10.61–12.54 and 3.26–3.46 mg 100 g^?1 wet basis, respectively) than that treated with NaHSO₃ (9.47–11.47 and 3.05–3.43 mg 100 g^?1 wet basis, respectively). Total phenolic content and water absorption index (wet basis) were highest at 65 °C when treated with NaHSO₃ (10.44 mg 100 g^?1 and 2.49 g g^?1 respectively) and CaCl₂ (9.52 mg 100 g^?1 and 2.85 g g^?1 respectively). Swelling capacity (wet basis) was highest at 60 °C when treated with CaCl₂ (2.96 g g^?1) whereas when treated with NaHSO₃ (2.85 g g^?1) it was highest at 55 °C. Freeze‐dried samples treated with NaHSO₃ had higher lightness and total phenolic content while CaCl₂‐treated samples had higher β‐carotene and ascorbic acid. The results showed that good quality flour could be produced after soaking in CaCl₂ and dried at 65 °C.     

Rootstock effects on salt tolerance of irrigated field-grown grapevines (Vitis vinifera L. cv. Sultana) 2. Ion concentrations in leaves and juice

Field vines of cv. Sultana, grown either on their own roots, or grafted to a range of rootstocks, were drip‐irrigated at three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five‐year period. Rootstocks comprised Ramsey, 1103 Paulsen, J17‐69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Concentrations of Cl^‐, Na+, K+, Ca²⁺ and Mg²⁺ were measured in petioles at flowering, and in laminae and grape juice at harvest, in each year of the trial. Vines on all rootstocks accumulated less chloride in either petioles at flowering or in laminae and juice at harvest compared with vines on own roots at all salinity treatments. By inference, all rootstocks behaved as chloride excluders relative to the roots of own‐rooted vines. 1103 Paulsen was the best chloride excluder based on lowest concentrations of accumulated Cl^‐ in petioles, laminae and grape juice at high salinity. Sultana on R3 rootstock at high salinity accumulated more Na+ in both laminae and grape juice (at harvest) than did Sultana on own roots or on any of the other rootstocks. Laminae K+ at harvest time was reduced at high salinity in Sultana on own roots and on all rootstocks. Concentrations of both Cl^‐ and Na+ in petioles at flowering and in laminae and grape juice at harvest showed no significant correlation with either yield (as kg of fresh grapes per vine) or vigour (as measured by fresh weight of one‐year‐old pruning wood per vine) for any salinity treatment. There was however, a strong positive correlation between yield and the subsequent weight of one‐year‐old pruning wood for all salinity treatments. There was also a negative correlation between Na+ concentrations in petioles at flowering and the subsequent weight of one year‐old‐pruning wood from the 0.40 dS/m treatment. Similar negative correlations were found between Na+ concentration in both laminae and grape juice at harvest time, and the subsequent weight of one‐year‐old pruning wood from the 0.40 dS/m treatment (but not from either the 1.75 or 3.50 dS/m treatments). Based on these findings and those from Walker et al. 2002a we conclude that a high innate vigour of a rootstock combined with moderate to high chloride and sodium exclusion ability represents the best combination for salt tolerance in Sultana grapevines as measured by yield at moderate to high salinity.     

Accumulation and implications of cadmium,cobalt and manganese in soils and vegetables irrigated with city effluent

BACKGROUND: In most parts of Pakistan, untreated city effluent is utilised for growing vegetables around large urban settlements such as Faisalabad. Farmers use it as a source of irrigation water and plant nutrients. However, its continuous use may have serious environmental implications, since it also contains heavy metals. In this study the Faisalabad city effluent was examined for irrigation quality and its impact on irrigated soils and vegetables. RESULTS: Irrigation hazard of the effluent was moderate (electrical conductivity (EC) 1.1–1.7 dS m^?1, Sodium adsorption ratio (SAR) 5.9–17.4 mmol^1/2 L^?1/2, Residual sodium carbonate (RSC) 1.0–2.1 mmol_c L^?1) at site 1 and strong (EC 3.7–4.1 dS m^?1, SAR 16.1–21.8 mmol^1/2 L^?1/2, RSC 4.0–9.1 mmol_c L^?1) at site 2. Mean concentrations of ammonium bicarbonate/diethylene triamine pentaacetic acid (AB/DTPA)‐extractable Cd, Co and Mn at upper soil depth (0.0–0.2 m) were respectively 0.080, 0.057 and 217.4 mg kg^?1 at site 1 and 0.101, 0.076 and 164.1 mg kg^?1 at site 2. CONCLUSION: The concentrations of Cd and Mn were above the permissible limits but that of Co was below the permissible limit for irrigation. The concentrations of Cd, Co and Mn tended to decrease with increasing soil depth. Accumulation of metals was higher in leaves irrespective of whether leaves were the edible or non‐edible component of shoots. Use of untreated city effluent for irrigation without risk assessment and management could be a serious hazard, impacting soil and crop quality and ultimately human health. Copyright © 2007 Society of Chemical Industry     

Quality of fresh‐cut tomatoes as affected by salt content in irrigation water and post‐processing ultraviolet‐C treatment

BACKGROUND: There is little information available concerning the effect of sanitizing agents, including ultraviolet (UV‐C) light, on nutritional composition of fresh‐cut produce. In this study, the influence of UV‐C light irradiation (3.2–19.2 kJ m^?2) on the nutritional quality of fresh‐cut tomato cv. Durinta grown under either low (2.4/2.8 dS m^?1) or high (4.9/7.7 dS m^?1) electrical conductivity (EC) of the hydroponic nutrient influx/efflux solution was investigated. RESULTS: When grown under low EC UV‐C light treatment reduced development of microbial population of fresh‐cut tomato, increased phenolic content and delayed degradation of vitamin C after 7 days of storage at 4–6 °C. UV‐C light irradiation had no significant effect on appearance, color or lycopene content of fresh‐cut tomato. In recently harvested intact tomatoes, the lycopene and vitamin C contents were 30% higher in tomatoes irrigated with high EC, whereas the phenolic content was unaffected by the salt treatment. After fresh‐cut processing, phenolic and vitamin C contents of fresh cuts produced from tomatoes treated with high EC decreased by > 10%. This decline was initially accelerated in tomato treated with UV‐C light irradiation. CONCLUSIONS: Our results revealed that fresh‐cut tomatoes are affected dissimilarly by UV‐C treatments, depending on the degree of salt stress undergone by plants before harvest. We determined the impact of a sanitizing procedure on nutritional composition, an effect often overlooked but with great significance to ensure overall quality of fresh produce. Our findings revealed the need for more nutritional studies addressing the effect of multiple stress factors from pre‐harvest to post‐processing stages. Copyright © 2008 Society of Chemical Industry     

A diminished capacity for chloride exclusion by grapevine rootstocks following long-term saline irrigation in an inland versus a coastal region of Australia

Shiraz and Chardonnay grapevines that had been initially assessed for Cl^‐ exclusion in the 1996 and 1997 harvest seasons at both Merbein (inland region of Victoria) and at Padthaway (sub‐coastal region of South Australia), were re‐evaluated in 2003 and 2004 at those same two locations. Both scion varieties were grown either on their own roots or were grafted to one of the following rootstocks: Ramsey, 1103 Paulsen, 140 Ruggeri, K51‐40, Schwarzmann, 101‐14, Rupestris St George and 1202 Couderc. Both sites had been irrigated with saline water since 1994. The salinity of irrigation water at Merbein was approximately 2.1 dS/m; at Padthaway irrigation salinity varied between approximately 1.6 dS/m and 2.5 dS/m during the survey period. Changes in the Cl^‐‐excluding ability of all rootstock/scion combinations between 1996, 1997 and 2003, 2004 were based upon analysis of Cl^‐ concentrations in grape juice and in laminae at harvest, as well as Electrical Conductivity (EC), pH and Sodium Adsorption Ratio (SAR) of the 1:5 soil:water extract. Taking juice Cl^‐ as indicative of rootstock effectiveness for Cl^‐ exclusion, and considering data from Merbein, our analyses demonstrated that overall means for Shiraz juice Cl^‐ increased from around 190 to 427 mg/L over the survey period (7 years). In Chardonnay grapevines at Merbein, overall mean concentrations of Cl^‐ in juice increased from around 70 to around 225 mg/L over 7 years. Significant differences between rootstocks were evident, with some rootstocks at Merbein showing a diminished capacity for Cl^‐ exclusion in 2003 and 2004. By contrast, in Padthaway there was no consistent deterioration in Cl^‐‐excluding capacity by rootstocks supporting either Shiraz or Chardonnay as scions. In 2004 there were significant differences between grapevines at Merbein and Padthaway in the concentration of Cl^‐ accumulated, even though the mean soil EC_1:5 after harvest for 0–90 cm depth was the same at both sites, namely 0.4 dS/m. Containment of grapevine salinity at Padthaway (relative to Merbein) between 1996/97 and 2003/04 was most likely due to factors such as a lower volume of saline irrigation, double the rainfall and 27% lower pan evaporation.     

Effect of calcium chloride on mechanical properties and microbiological characteristics of cv. Conservolea naturally black olives fermented at different sodium chloride levels

The effect of calcium chloride (CaCl₂)(5 gL^?1) and sodium chloride (NaCl) concentration (40, 60 and 8 gL^?1) on the microbiological and mechanical properties of naturally black olives of cv. Conservolea in brines was studied. In 40 and 60 g L^?1 brines the growth of lactic acid bacteria was favoured over that of yeasts, resulting in rather complete lactic acid fermentation as indicated by high free acidity (9.8–11.5 g lactic acid L^?1) and low pH (3.7–3.8). At 80 g L^?1 brine, yeasts were the dominant members of the microflora, rendering a product with lower acidity (8 g lactic acid L^?1) and higher pH (4.3–4.5). In the presence of CaCl₂ there was a consistent increase in the depth of the peripheral region in which cell wall breakage occurred. When cells separated, perforated walls were observed at sites associated with plasmodesmata. The flesh was strongest and stiffest when CaCl₂ was added to olives treated with 40 g L^?1 brine, consistent with cell wall breakage being the predominant mode of failure. The only observed effect on the mechanical properties of the skin was a stiffening at 60 g L^?1 brine on addition of CaCl₂. Copyright © 2007 Society of Chemical Industry     

Effect of salinity and Ramsey rootstock on ion concentrations and carbon dioxide assimilation in leaves of drip-irrigated, field-grown grapevines (Vitis vinifera L. cv. Sultana)

Salinity treatments of 0.43, 1.7 and 3.4 dS/m were applied through a drip-irrigation system to four-year-old vines of own-rooted Sultana (S_O) and Sultana on Ramsey rootstock (Sr) The vines were planted in spring 1987 and established for two years under irrigation with low salinity (0.43 dS/m) water before commencing the range of salinity treatments in spring 1989. The effects of salinity and rootstock on yield, size and composition of berries, canopy size, lamina CO₂ assimilation, leaf water relations and lamina ion concentrations were studied between veraison and harvest during the second season of salinity treatments. Mature leaves of S_R had higher rates of CO₂ assimilation (leaf area basis) and stomatal conductance than comparable leaves of S_O. The high salinity treatment (3.4 dS/m) reduced CO₂ assimilation rate of S_O but not of S_R. Medium salinity (1.7 dS/m) had no significant effect on CO₂ assimilation rate of either type. Laminae of S_O accumulated significantly higher concentrations of chloride than S_R vines at all salinity levels. There was a significant negative correlation (r²= 0.44) between CO₂ assimilation rate and laminae chloride of S_O. Leaf sodium concentrations increased with increasing salinity, but concentrations in laminae at high salinity were similar in S_O and S_R, with S_R showing no reduction in CO₂ assimilation. Leaf potassium concentrations were higher in S_R, but decreased with increasing salinity, whereas magnesium concentrations were similar in S_O and S_R vines but increased in both at high salinity. Leaf water potential and relative water content were not significantly affected by salinity in either S_O or S_R vines. Both vine types had reduced total leaf area and pruning wood weights as salinity increased, but they were greater in S_R at all salinity levels because of the higher inherent capacity for biomass production in S_R vines. The bigger canopies, lower lamina chloride concentrations and ‘normal’ photosynthesis rates of S_R vines at 3.4 dS/m enabled these vines to mature crops with similar berry weights, sugar contents and fruit yield compared with those of S_O vines at 0.43 dS/m. The research demonstrated the benefit of using Ramsey rootstock for Sultana under saline field conditions and provided a physiological explanation for their higher salt tolerance.     

Yield-salinity relationships of different grapevine (Vitis vinifera L.) scion-rootstock combinations

Three data sets derived from 5– or 6‐year field experiments at Merbein (Victoria), Dareton (New South Wales) and Loxton (South Australia) were used to assess the relationship between yield of own‐rooted or grafted grapevines and electrical conductivity of the saturated soil paste extract (ECe). This involved a non‐linear least squares fit method to determine the threshold of ECe at which yield begins to decline and the slope of the yield reduction with increasing ECe above that threshold. Threshold and slope are the two key parameters in this piece wise linear model of grapevine response to salinity. The soil ECe values were integrated to take account of both spatial and temporal variation in soil salinity within the profile. The ECe threshold for own‐rooted Sultana at Merbein in the Sunraysia region was found to be 2.3 0.2 dS/m and the slope of yield reduction above the threshold was 8.9 1.2 % per 1 dS/m increase in soil ECe. At Dareton, a similar threshold of 2.1 0.3 dS/m was found for own‐rooted Sultana, however the higher slope of the yield reduction (15.0 2.0 %) relative to the same vines at Merbein may have been related to the higher sodium adsorption ratio (SAR) in irrigation water and its impacts on soil physical properties, especially in that part of the vineyard with a heavier soil type. The rootstock Ramsey resulted in a threshold of 3.3 0.2 dS/m and slope of 5.7 0.4% with the scion Colombard at Loxton, indicating a more tolerant combination of scion‐rootstock to salinity. The rootstocks 1103 Paulsen and R2 with Sultana as scion were the most salt tolerant, with no discernible yield reduction until ECe exceeded about 4 dS/m. Of four other rootstocks with Sultana as scion, compared with own‐rooted Sultana, J17–69, and R4 had similar threshold values (2.3 0.2 and 2.5 0.2 dS/m) and slopes of yield reduction (10.1 1.9 % and 8.0 0.5 %, respectively), while R1 had a similar threshold of 1.8 0.2 dS/m but a lower slope of yield reduction (4.3 0.9 %) than Sultana on own roots and R3, J17–69, R1 and R4 rootstocks. Comparatively, R3 rootstock responded differently by way of a higher threshold of 3.0 0.2 dS/m than own‐rooted Sultana and J17–69 and R1 rootstocks and a higher slope of yield reduction of 12.4 1.0 % relative to Sultana on own roots and R4 and R1 rootstocks. Based on our long‐term studies of yield‐salinity relationships on contrasting sites, the pre‐eminence of certain rootstocks in conferring tolerance to soil salinity has been confirmed. Ramsey, 1103 Paulsen, and a new hybrid designated here as R3 were generally outstanding, with Ramsey varying only slightly in its comparative effectiveness when grafted to different scion varieties. An overall interaction between scion variety and rootstock genotype was thus evident in the form of yield‐salinity relationships.     

Effect of pH and NaCl/CaCl2 on the solubility and emulsifying properties of sweet potato protein

BACKGROUND: The effects of NaCl and CaCl₂ on the solubility and emulsifying properties, namely emulsifying activity index (EAI) and emulsion stability index (ESI) of sweet potato proteins (SPPs) at pH 1–10, were investigated. RESULTS: At lower NaCl (0.1 mol L^?1) and CaCl₂ (0.05 mol L^?1) concentrations, the solubility profiles of the SPPs were very similar to those in distilled water, and the lowest solubility occurred at pH 4. Increased NaCl and CaCl₂ concentration resulted in lower SPP solubility in most of the pH studied (P < 0.05). At pH < 3, NaCl improved the EAI of SPP while at pH > 7 it reduced the EAI of the SPP (P < 0.05). Moreover, addition of NaCl also resulted in reduction of ESI of the SPP in most of the pH studied (P < 0.05). On the other hand, the presence of 0.2 mol L^?1 CaCl₂ rendered the EAI and ESI of the SPPs independent of the influence of pH. CONCLUSION: The present studies show that pH and salts modified the emulsifying properties of the SPPs, and CaCl₂ at a certain concentration could be used to improve the emulsifying properties of the protein. Copyright © 2008 Society of Chemical Industry     

Rootstock effects on salt tolerance of irrigated field-grown grapevines (Vitis vinifera L. cv. Sultana). 3. Fresh fruit composition and dried grape quality

Field‐grown vines of cv. Sultana on either their own roots or grafted to a range of rootstocks, were drip‐irrigated at one of three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five year period. Rootstocks were Ramsey, 1103 Paulsen, J17‐69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Grape juice total soluble solids, titratable acidity and pH were measured at harvest, while colour of dried fruit was measured before and after processing and again after six months storage. Damage index (an indicator of skin damage) was measured post‐processing; sugar crystal formation in dried grapes and dried grape compaction were measured post‐storage. There was a strong salinity x rootstock interaction for grape juice soluble solids concentration, soluble solids yield (the product of soluble solids concentration and fruit yield) and pH, but not for titratable acidity when analysed on the basis of 5 year means. Small increases (< 5%) in juice soluble solids concentration were recorded at medium salinity (1.75 dS/m) for the low vigour genotypes, Sultana on own‐roots and on J17‐69 rootstock, based on the 5 year means and Fisher's protected (interaction) LSDs. Moderate increases (< 10%) also occurred in years of low crop load e.g. 1993 at high salinity for the high vigour rootstock R2 and in 1995 at medium salinity for Sultana on own roots and at high salinity for Sultana on R1 rootstock. By contrast, decreases in soluble solids concentration occurred with increasing salinity for the high vigour rootstocks (Ramsey, 1103 Paulsen and R2) in years of high crop load e.g. 1992. Small (< 2%) increases in grape juice pH were recorded at high salinity for Sultana on R3 rootstock and moderate increases (< 7%) in grape juice titratable acidity were recorded at high salinity for Sultana on own roots and Sultana on J17‐69, R1, R2 and R4 rootstocks. Dried grapes from all treatments achieved a light amber colour (quality grade termed 5 crown light) and were generally of high quality. Sultanas from own‐rooted grapevines were redder (higher ‘a‐value’) than sultanas from 1103 Paulsen and Ramsey when assessed as unprocessed fruit, after processing (both years) and after 6 weeks storage. While soluble solids yields per vine were 23–31% lower at high salinity for Sultana on own roots and on R1, R3 and R4 rootstocks, they were unaffected by high salinity for Ramsey, 1103 Paulsen and R2 rootstocks. Moreover, soluble solids yields for Sultana on Ramsey, 1103 Paulsen and R2 rootstocks were 1.4 to 2.5‐fold higher than for Sultana on the other rootstocks at high salinity. This study has shown that over a 5 year period rootstocks such as Ramsey, 1103 Paulsen and R2 grafted with Sultana were tolerant of salinity, producing dried grapes of generally high quality.     

Interactive effect of supplemental ultraviolet B and elevated ozone on seed yield and oil quality of two cultivars of linseed (Linum usitatissimum L.) carried out in open top chambers

BACKGROUND: Current scenarios of global climate change predict a significant increase in ultraviolet B (UV‐B) and tropospheric ozone (O₃) in the near future. Both UV‐B and O₃ can have detrimental effects on the productivity and yield quality of important agricultural crops. The present study was conducted to investigate the individual and interactive effects of supplemental UV‐B (sUV‐B) (ambient + 7.2 kJ m^?2 day^?1) and O₃ (ambient + 10 ppb) on the yield and oil quality of two cultivars of linseed (Linum usitatissimum L.). RESULTS: The mean monthly ambient O₃ concentration varied from 27.7 to 59.0 ppb during the experimental period. O₃ affected fruit formation, while sUV‐B was mainly responsible for ovule abortion. Seed sugar and protein contents showed maximum reduction in O₃‐treated plants, while mineral nutrient levels were most affected by sUV‐B + O₃ treatment. Rancid oil of low nutritional quality and containing long‐chain fatty acids was favoured along with a decrease in oil content. CONCLUSION: sUV‐B and O₃ individually as well as in combination caused deterioration of the yield and quality of oil and seeds of linseed. However, the individual effect of O₃ was more damaging than the effect of sUV‐B or sUV‐B + O₃, and cultivar T‐397 performed better than Padmini. © 2012 Society of Chemical Industry     

Effect of fruit ripeness and method of fruit drying on the extractability of avocado oil with hexane and supercritical carbon dioxide

BACKGROUND: Oil yield from avocado fruit may be influenced by fruit pre‐treatment and extraction method. Unripe and ripe avocado fruit pieces were deep‐frozen at ? 20 °C and either freeze‐dried or oven‐dried (80 °C). Oil yield from these samples was determined after extraction with hexane and supercritical carbon dioxide (SC‐CO₂). The fruit samples were examined using scanning electron microscopy before and after oil extraction. RESULTS: Average oil yield from ripe fruit (freeze‐dried and oven‐dried combined) was 72 g kg^?1 higher than from unripe fruit for SC‐CO₂ extracts and 61 g kg^?1 higher for hexane extracts. This may be due to enzymatic degradation of parenchyma cell walls during ripening, thus making the oil more available for extraction. Freeze‐dried samples had a mean oil yield 55 g kg^?1 greater than oven‐dried samples for SC‐CO₂ extracts and 31 g kg^?1 higher for hexane extracts. However, oil yields from ripe fruit (freeze‐dried and oven‐dried) subjected to hexane extraction were not significantly different. All hexane extracts combined had a mean oil yield 93 g kg^?1 higher than SC‐CO₂ extracts. CONCLUSION: SC‐CO₂ may be more selective and may create paths of least resistance through the plant material. Hexane, on the other hand, is less selective and permeates the whole plant material, leading to more complete extraction and higher oil yields under the experimental conditions. Copyright © 2007 Society of Chemical Industry     

Purification,characterisation and application of α‐l‐rhamnosidase from Penicillium citrinum MTCC‐8897

An α‐l ‐rhamnosidase secreted by Penicillium citrinum MTCC‐8897 has been purified to homogeneity from the culture filtrate of the fungal strain using ammonium sulphate precipitation and cation‐exchange chromatography on carboxymethyl cellulose. The sodium dodecyl sulphate/polyacrylamide gel electrophoresis analysis of the purified enzyme gave a single protein band corresponding to the molecular mass 51.0 kDa. The native polyacrylamide gel electrophoresis also gave a single protein band confirming the enzyme purity. The K_m and V_max values of the enzyme for p‐nitrophenyl α‐l ‐rhamnopyranoside were 0.36 mm and 22.54 μmole min^?1 mg^?1, respectively, and k_cat value was 17.1 s^?1 giving k_cat/K_m value of 4.75 × 10⁴ m ^?1 s^?1. The pH and temperature optima of the enzyme were 7.0 and 60 °C, respectively. The purified enzyme liberated l ‐rhamnose from naringin, rutin, hesperidin and wine, indicating that it has biotechnological application potential for the preparation of l ‐rhamnose and other pharmaceutically important compounds from natural glycosides containing terminal α‐l ‐rhamnose and also in the enhancement of wine aroma.     

Sorption of ethyl acetate and d‐limonene in poly(lactide) polymers

Poly(lactide) (PLA) polymers have garnered increased attention in the last few years as food packaging materials because they are environmentally friendly polymers. As the production of PLA increases and price per pound drops, PLA is becoming a growing alternative as a green food packaging material. In this research, the organic vapor barrier properties of commercially available PLA polymers were studied. Gravimetric sorption tests in PLA films were carried out, and the diffusion (D), solubility (S) and permeability (P) coefficients for ethyl acetate and d‐limonene in PLA were determined. For ethyl acetate, values of P = 1.22 × 10^?17 kg m m^?2 s^?1 Pa^?1, D = 2.63 × 10^?15 m² s^?1, and S = 4.62 × 10^?3 kg m^?3 Pa^?1) at 45 °C and a partial pressure of 12 654 Pa were obtained. For d‐limonene, no trace was detected after 21 days of testing at 45 °C and 258 Pa, which indicates a permeability coefficient lower than 9.96 × 10^?21 kg m m^?2 s^?1 Pa^?1. Poly(lactide) polymers demonstrated good aroma barrier to ethyl acetate and d‐limonene, and will most likely be good aroma barriers. PLA is not likely to promote flavor loss by either permeation or scalping. Copyright © 2005 Society of Chemical Industry     

Purification and functional characterisation of an α‐l‐rhamnosidase from Penicillium citrinum MTCC‐3565

An extracellular α‐l ‐rhamnosidase from Penicillium citrinum MTCC‐3565 has purified to homogeneity from its culture filtrate using ethanol precipitation and cation‐exchange chromatography on carboxymethyl cellulose. The purified enzyme gave a single protein band corresponding to molecular mass of 45.0 kDa in SDS‐PAGE analysis showing the purity of the enzyme preparation. The native PAGE analysis showed the monomeric nature of the purified enzyme. Using p‐nitrophenyl α‐l ‐rhamnopyranoside as substrate, K_m and V_max values of the enzyme were 0.30 mm and 27.0 μm min mg^?1, respectively. The k_cat value was 20.1 s giving k_cat/K_m value of 67.0 mm s^?1 for the same substrate. The pH and temperature optima of the enzyme were 8.5 and 50 °C, respectively. The activation energy for the thermal denaturation of the enzyme was 29.9 KJ mol^?1. The α‐l ‐rhamnosidase was able to hydrolyse naringin, rutin and hesperidin and liberated l ‐rhamnose, indicating that the purified enzyme can be used for the preparation of α‐l ‐rhamnose and pharmaceutically important compounds by derhamnosylation of natural glycosides containing terminal α‐l ‐rhamnose. The α‐l ‐rhamnosidase was active at the level of ethanol concentration present in wine, indicating that it can be used for improving wine aroma.