Starch glucose coating-induced postharvest shelf-life extension of cucumber.

Cucumber (Cucumis sativus L.) is a rich source of vitamins, minerals, and antioxidants. Its post-harvest deterioration leads to a limited shelf-life up to 5-7 days. To avoid such loss, the present study investigates the potential effect of starch glucose (SG) coating on the extension of its shelf-life, after harvest. 1.0, 1.5 and 2.0 µM of starch with 2.5 µM D-glucose solutions were coated over freshly harvested cucumbers and stored at refrigerated temperature (±4 °C) for 30 days. 1.5 µM starch plus 2.5 µM D-glucose displayed significantly better results as per the skin colour and sensory evaluation test. This level of SG coating extended the shelf-life of cucumbers up to 30 days with least reduction in weight loss, total soluble sugar, protein, catalase activity, peroxidase activity and increased in proline content, 2, 2-diphenyl-1-picrylhydrazyl antioxidant activities and ferrous ion chelating activities.

Extension of postharvest shelf-life in green bell pepper (Capsicum annuum L.) using exogenous application of polyamines (spermidine and putrescine).

To extend the postharvest shelf-life of green bell pepper (Capsicum annuum L.), an exogenous application of two polyamines, Spermidine and Putrescine (SPD-PUT), was tested in multiple combinations (10 µM plus 10 µM, 20 µM plus 20 µM, and 30 µM plus 30 µM) at 4 ±â€¯1 °C for 40 days. The titratable acidity, protein content, activities of catalase and peroxidase, chlorophyll and capsaicin content gradually decreased for all the treated and untreated fruits throughout the storage period. On the other hand, proline content and antioxidant 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging activity continuously increased with the extension of time-span under storage. Among the three treatment combinations, the combination of 20 µM SPD and 20 µM PUT was found to be the optimum, based on the response of all the morphological and physicochemical traits assessed. The same combination was effective in sustaining the quality of green bell pepper following its harvest, for a period of at least 40 days.

The retrospect and prospect of the applications of biotechnology in Phoenix dactylifera L.

Date palm (Phoenix dactylifera L.) is one of the most important fruit trees that contribute a major part to the economy of Middle East and North African countries. It is quintessentially called "tree of life" owing to its resilience to adverse climatic conditions, along with manifold nutritional-cum-medicinal attributes that comes from its fruits and other plant parts. Being a tree with such immense utility, it has gained substantial attention of tree breeders for its genetic advancement via in vitro biotechnological interventions. Herein, an extensive review of biotechnological research advances in date palm has been consolidated as one of the major research achievements during the past two decades. This article compares the different biotechnological techniques used in this species such as: tissue and organ culture, bioreactor-mediated large-scale propagation, cell suspension culture, embryogenic culture, protoplast culture, conservation (for short- and long-term) of germplasms, in vitro mutagenesis, in vitro selection against biotic and abiotic stresses, secondary metabolite production in vitro, and genetic transformation. This review provides an insight on crop improvement and breeding programs for improved yield and quality fruits; besides, it would undeniably facilitate the tissue culture-based research on date palm for accelerated propagation and enhanced production of quality planting materials, along with conservation and exchange of germplasms, and genetic engineering. In addition, the unexplored research methodologies and major bottlenecks identified in this review should be contemplated on in near future.

Changes in antioxidant and biochemical activities in castor oil-coated Capsicum annuum L. during postharvest storage.

This study, for the first time, evaluates the efficiency of castor oil when used as an external coating on Capsicum annuum L., to increase postharvest storage-life at 4 ± 1 °C. The castor oil-coated fruits were successfully stored for 36 days, while the non-coated fruits could only sustain for 18 days. Throughout the storage period (at 9-day intervals), different antioxidants and biochemical assays (allied with storage) such as titratable acidity, ascorbic acid content, ferrous ion chelating activity, reducing power, DPPH scavenging activity, hydroxyl radical scavenging activity, total phenolic content, total sugar estimation, and enzymatic study of polyphenol oxidase and pectate lyase, were assessed. During storage, the castor oil-coated fruits showed a substantial decrease in titratable acidity, ascorbic acid content, total phenolic content, including antioxidant activities such as reducing power and DPPH activity; however, an increase in ferrous ion chelating activity, total soluble sugar content, polyphenol oxidase activity and initial pectate lyase activity was observed, in contrast to that of the non-coated fruits. The application of castor oil proved to be effective in delaying the ripening process of fruits during storage.

In vitro biotechnological advancements in Malabar nut (Adhatoda vasica Nees): Achievements, status and prospects.

Adhatoda vasica Nees, belonging to family Acanthaceae, is a well-known medicinal plant. It is endorsed for its pyrroloquinazoline alkaloids and its derivatives, such as vasicine and vasicinone. Germinating A. vasica seeds is a tedious task; on that account, vegetative propagation is the preferred method for its multiplication. For rapid and large-scale multiplication, germplasm conservation as well as secondary metabolites production, in vitro culture of A. vasica was preferred over conventional propagation by several researchers; however, some major applications of this tissue culture technique are still awaiting to undergo extensive research. The present review, for the first time, illustrates all the major achievements associated with in vitro regeneration of A. vasica, reported till date and highlights the future prospects.

Concurrent production and relative quantification of vasicinone from in vivo and in vitro plant parts of Malabar nut (Adhatoda vasica Nees).

The present study documents a simultaneous production and comparative assessment of extracted vasicinone from in vivo (leaves and stems) and in vitro (leaves, stems and calli) plant parts of Adhatoda vasica Nees, a well-known medicinal plant. High-performance thin layer chromatography (HPTLC) analysis of the above-mentioned plant parts, collected at their 60-day-old growth stage, was performed via methanolic extraction and with the aid of toluene:butanol:butyl acetate (9:0.5:0.5; v/v/v) solvent system. The method was validated with the help of aluminium sheet precoated with silica gel 60 F254 TLC plates, following the ICH guidelines in order to maintain accuracy, precision and repeatability. Correlation coefficient, limit of detection and limit of quantification values were found to be reasonable. The outcome revealed a linearity that ranged between 2 and 6 µg/spot. During the comparison of estimated vasicinone quantity from in vivo and in vitro plant parts, it was evident that in vitro samples produced relatively higher vasicinone than that of the in vivo counterparts. Maximum vasicinone (6.402 ± 0.010% of dry weight) production was quantified from in vitro leaves followed by calli (5.222 ± 0.092% of dry weight) and in vitro stems (2.007 ± 0.041% of dry weight). On the other hand, in vivo leaves and stems produced comparatively lower quantities of vasicinone (2.412 ± 0.139 and 1.933 ± 0.046% of dry weight, respectively) suggesting the in vitro clonal propagation as a superior approach in comparison to in vivo propagation. Nonetheless, simultaneous production from both the sources (in vivo and in vitro plant parts) provides a new avenue for augmented production of vasicinone.