Retention of freshness and isothiocyanates in fresh-cut radish (Raphanus sativus var. Longipinnatus) through glucose dip treatment.

Experiments were carried out with the objective of enhancing shelf life and maintain quality of fresh-cut radish slices during storage at 8 °C. Dip treatment of radish slices in 20 g/L glucose solution for five minutes retained the quality attributes viz., surface colour, sensory properties and antioxidant capacity of the slices till six days of storage. Isothiocyanates were also retained better due to glucose dip. Biplot generated through principal component analysis of head space volatiles from fresh and stored radish slices showed that fresh and glucose treated slices grouped together with 4-methyl thio-3-butenyl isothiocyanate. Accumulation of sulphurous volatiles such as methyl disulphide, dimethyl trisulphide, 2-pentanethiol was observed in control (undipped) radish slices, indicating their probable role as spoilage indicator volatiles. Thus, glucose pre-treatment can be considered as a practical method for quality retention of fresh-cut radish. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05276-1.

CFB box wrapping: a new shrink wrapping technology for extension of storage life of colour capsicum (cv. Bachata).

Capsicums lose water very rapidly after harvest and the moisture loss causes severe shriveling making them unmarketable within 2-3 days. The moisture loss occurs even under low temperature conditions, though at lesser rates. Bell peppers packed in corrugated fiber board boxes (CFB) tend to lose moisture continuously as these boxes are permeable to both water vapour and respiratory gases even if they are non-ventilated. To reduce the moisture loss and maintain freshness, yellow colour capsicum (cv. Bachata) were packed in CFB boxes and over wrapped with different semi-permeable films using shrink wrapping technology. This box shrink wrapping significantly lowered the weight loss and maintained firmness of capsicum at ambient (25.7-33.2 °C and 25-63% RH) and low temperature (8 °C ± 0.5 and 80 ± 5% RH) conditions. Yellow colour capsicums packed in this way could be stored for 11 days at ambient temperature with a weight loss of < 6% as compared to about 20% weight loss in non-wrapped fruits. The storage life could be extended to 5 weeks by storing these shrink wrapped boxes at 8 °C without any shriveling and with a weight loss of < 5%. In addition to maintaining high humidity, the lower O2 and higher CO2 levels maintained surrounding the produce in the wrapped boxes helped to avoid shriveling and to retain the quality in terms of surface colour, firmness and other quality traits. The absorption of excessive relative humidity by CFB itself in the over wrapped boxes helped in avoiding condensation of water droplets. This in turn avoided the development of fungal growth and thus the risk of fruit decay.

Effect of modified atmosphere packaging on the extension of storage life and quality maintenance of pomegranate (cv. 'Bhagwa') at ambient and low temperatures.

Pomegranates (cv. 'Bhagwa') packed in four semi-permeable films (Cryovac® BDF-2001, D-955, RD-106 and normal LDPE) were stored at ambient temperature (25-30 °C, 60-70% RH) and low temperature (8 °C, 80-85% RH) to study the effect of modified atmosphere (MA) packaging on storage life extension and quality maintenance. O2 and CO2 levels generated inside MA packs differed significantly with the film type wherein extremely high CO2 (> 70%) and low O2 (1% or less) were observed in BDF film during 3 weeks at ambient temperature and 3 months at 8 °C. Moderate O2 (3-8%) and CO2 (7-11%) were maintained in D-955 film, whereas very high O2 (18-20%) and low CO2 (2-4%) were maintained in RD-906 film. Significantly low weight loss of 0.73 and 0.52% was observed in MA packed (D-955) fruits after 3 weeks at ambient and 3 months at 8 °C respectively compared to 19.0 and 17.8% in non-packed fruits. Fruits packed in D-955 film also retained original peel colour (L*, h° and C*), whereas colour was adversely affected in fruits packed in low permeable BDF film. MA packaging maintained peel thickness and peel moisture, significantly higher than non-packed fruits at both temperatures. TSS, acidity, sugars, antioxidants and sensory qualities were better in D-955 and LDPE packed fruits at both ambient and 8 °C storage, whereas quality was adversely affected in BDF film packed fruits. MA packed (D-955 and LDPE) fruits had less spoilage up to 3 weeks at ambient (5.5 and 8.3%) and 3 months at 8 °C (2.8 and 9.7%). Quality got deteriorated by 4 weeks at ambient temperature and 4 months at 8 °C with enhanced spoilage. Pomegranate fruits cv. 'Bhagwa' can thus be stored safely for 3 weeks at ambient and 3 months at 8 °C storage by MA packaging in D-955 or LDPE film with least weight loss and maintenance of nutritional quality.

Individual shrink wrapping extends the storage life and maintains the quality of pomegranates (cvs. 'Mridula' and 'Bhagwa') at ambient and low temperature.

The present investigation was carried out to study the response of two commercial pomegranate cultivars to individual shrink wrapping in extending the storage life and quality maintenance. Pomegranate fruits ('Mridula' and 'Bhagwa') were individually shrink wrapped using three semi-permeable films (Cryovac® BDF-2001, D-955 and normal LDPE) and stored at ambient (25-32 °C and 49-67% RH) and low temperature (8 °C and 75-80% RH). Shrink wrapping greatly reduced weight loss in both cultivars irrespective of the film used and storage temperature. Weight loss in shrink wrapped (D-955 film) 'Mridula' and 'Bhagwa' after 1 month storage at ambient temperature was respectively 1.40 and 1.05%, when compared to 22.92 and 22.53% in non-wrapped fruits. After 3 months at 8 °C, shrink wrapped 'Mridula' and 'Bhagwa' fruits lost only 0.43 and 0.68% weight respectively, compared to 17.23 and 21.67% in non-wrapped ones. Shrink wrapping significantly reduced the respiration rate at ambient temperature and the response varied with variety and film used. Shrink wrapped fruits of both cultivars retained the original peel colour (Hunter h∘ and C* values) to a maximum extent during 3 months storage at 8 °C and shelf-life period at ambient temperature. Irrespective of variety and film, shrink wrapping maintained the peel thickness and peel moisture content, significantly much higher than non-wrapped fruits at both temperatures. Compared to 'Mridula' cultivar, 'Bhagwa' responded well to shrink wrapping during prolonged storage at both temperatures with better maintenance of quality in terms of appearance, colour, juice content, TSS, acidity, sugars and sensory attributes. At ambient temperature, shrink wrapping with D-955 or LDPE film extended the storage life of 'Mridula' and 'Bhagwa' for 3 weeks and 1 month respectively, whereas at 8 °C both could be stored for 3 months with 3 days of shelf life.

A Study on the Expression of Genes Involved in Carotenoids and Anthocyanins During Ripening in Fruit Peel of Green, Yellow, and Red Colored Mango Cultivars.

Mango (Mangiferaindica L.) fruits are generally classified based on peel color into green, yellow, and red types. Mango peel turns from green to yellow or red or retain green colors during ripening. The carotenoids and anthocyanins are the important pigments responsible for the colors of fruits. In the present study, peels of different colored cultivars at three ripening stages were characterized for pigments, colors, and gene expression analysis. The yellow colored cultivar "Arka Anmol" showed higher carotenoid content, wherein ß-carotene followed by violaxanthin were the major carotenoid compounds that increased during ripening. The red colored cultivars were characterized with higher anthocyanins with cyanidin-3-O-monoglucosides and peonidin-3-O-glucosides as the major anthocyanins. The gene expression analysis by qRT-PCR showed the higher expression of carotenoid biosynthetic genes viz. lycopene-ß-cyclase and violaxanthin-de-epoxidase in yellow colored cv. Arka Anmol, and the expression was found to increase during ripening. However, in red colored cv. "Janardhan Pasand," there is increased regulation of all anthocyanin biosynthetic genes including transcription factors MYB and basic helix loop. This indicated the regulation of the anthocyanins by these genes in red mango peel. The results showed that the accumulation pattern of particular pigments and higher expression of specific biosynthetic genes in mango peel impart different colors.

Salinity-driven decadal changes in phytoplankton community in the NW Arabian Gulf of Kuwait.

Evaluation of hydrological data obtained between 2000 and 2013 from a time series station in Kuwait Bay (station K6) and an offshore southern location (station 18) off Kuwait showed drastic increase in salinity by 6 units. We tested the hypothesis that increased salinity impacted phytoplankton community characteristics in these semiarid waters. The Arabian Gulf receives seasonal freshwater discharge in the north via Shatt Al-Arab estuary with a peak during March-July. A north to south gradient in the proportion of the freshwater exists between station A in the vicinity of Shatt Al-Arab estuary and station 18 in the southern offshore area. At station A, the proportion of freshwater was the highest (25.6-42.5%) in 1997 but decreased to 0.8-4.6% by 2012-2013. The prevailing hyperhaline conditions off Kuwait are attributed to decrease in the river flow. Phytoplankton data showed a decrease in the number of constituent taxa in the last one decade from 353 to 159 in the Kuwait Bay and from 164 to 156 in the offshore area. A shift in their biomass was caused by a decrease in diatom species from 243 to 92 in the coastal waters and from 108 to 83 in the offshore areas with a concomitant increase of smaller algae. Mutivariate agglomerative hierarchical cluster analysis, non-metric multi-dimensional scaling, and one-way analysis of similarity analyses on phytoplankton data at different taxonomic levels confirmed significant changes in their community organization on a decadal scale. These evidences support our hypothesis that the salinity-related environmental changes have resulted in a coincidental decrease in species diversity and significant changes in phytoplankton community between the years 2000-2002 and 2012-2013, off Kuwait. This in turn would affect the pelagic trophodynamics as evident from a drastic decrease in the catch landings of Tenulosa ilisha (Suboor), Carangoides sp. (Hamam), Otolithes ruber (Nowaiby), Parastromateus niger (Halwaya), and Epinephelus coioides (Hamoor) in Kuwait.

Synchrotron-based XRD from rat bone of different age groups.

Synchrotron-based XRD spectra from rat bone of different age groups (w, 56 w and 78w), lumber vertebra at early stages of bone formation, Calcium hydroxyapatite (HAp) [Ca10(PO4)6(OH)2] bone fill with varying composition (60% and 70%) and bone cream (35-48%), has been acquired with 15keV synchrotron X-rays. Experiments were performed at Desy, Hamburg, Germany, utilizing the Resonant and Diffraction beamline (P9), with 15keV X-rays (λ=0.82666 A0). Diffraction data were quantitatively analyzed using the Rietveld refinement approach, which allowed us to characterize the structure of these samples in their early stages. Hydroxyapatite, received considerable attention in medical and materials sciences, since these materials are the hard tissues, such as bone and teeth. Higher bioactivity of these samples gained reasonable interest for biological application and for bone tissue repair in oral surgery and orthopedics. The results obtained from these samples, such as phase data, crystalline size of the phases, as well as the degree of crystallinity, confirm the apatite family crystallizing in a hexagonal system, space group P63/m with the lattice parameters of a=9.4328Å and c=6.8842Å (JCPDS card #09-0432). Synchrotron-based XRD patterns are relatively sharp and well resolved and can be attributed to the hexagonal crystal form of hydroxyapatite. All the samples were examined with scanning electron microscope at an accelerating voltage of 15kV. The presence of large globules of different sizes is observed, in small age groups of the rat bone (8w) and lumber vertebra (LV), as distinguished from, large age groups (56 and 78w) in all samples with different magnification, reflects an amorphous phase without significant traces of crystalline phases. Scanning electron microscopy (SEM) was used to characterize the morphology and crystalline properties of Hap, for all the samples, from 2 to 100µm resolution.

Improvement in shelf life of minimally processed cilantro leaves through integration of kinetin pretreatment and packaging interventions: Studies on microbial population dynamics, biochemical characteristics and flavour retention.

Effect of integrating optimized combination of pretreatment with packaging on shelf life of minimally processed cilantro leaves (MPCL) was appraised through analysis of their sensory attributes, biochemical characteristics, microbial population and flavour profile during storage. Minimally pretreated cilantro leaves pretreated with 50ppm kinetin and packed in 25µ polypropylene bags showed a shelf life of 21days. Optimized combination helped in efficiently maintaining sensory parameters, flavour profile, and retention of antioxidants in MPCL until 21days. Studies conducted on the effect of optimized combination on microbial population and flavour profile revealed that among different microorganisms, pectinolysers had a significant effect on spoilage of MPCL and their population of ⩽3.59logcfu/g was found to be acceptable. Principal component analysis of headspace volatiles revealed that (E)-2-undecenal, (E)-2-hexadecenal, (E)-2-tetradecenal & (E)-2-tetradecen-1-ol in stored samples clustered with fresh samples and therefore, could be considered as freshness indicators for MPCL.

Effect of pretreatments and modified atmosphere packaging on the shelf life and quality of fresh- cut green bell pepper.

Present study was aimed at understanding the effect of pretreatments and modified atmosphere packaging on the quality of fresh-cut green bell pepper (Capsicum annuum L.) during low temperature storage. Dip treatment of freshly cut green bell pepper pieces in 2 % calcium propionate followed by surface drying and subsequent packing in cryovac PD961 film which maintained an equilibrium modified atmosphere of 13-14 % O2 and 7 % CO2 helped to extend the marketability till 9 days storage at 8 °C. The microbiological quality was at the best level up to 6 days of storage, as evidenced by a surge in aerobic plate count, pectinolysers and pseudomonads on subsequent days. Head space volatile analysis of the produce at regular intervals showed a reduction in monoterpenoids and simultaneous increase of aldehydes and ketones, sesquiterpenoids, esters, furans and pyrazines during storage. Principal component analysis of the head space volatiles identified, cis - ocimene, 1,3,8-paramenthatriene, trans 3- caren 2-ol, bergamotene, 2-hexenal, ethyl 1- decanol, (E)-3- hexenol and heptane thiol as the markers of freshness in minimally processed green bell pepper.

Individual shrink wrapping extends the storage life and maintains the antioxidants of mango (cvs. 'Alphonso' and 'Banganapalli') stored at 8 °C.

Freshly-harvested mature green mangoes (cvs. 'Alphonso' and 'Banganapalli') were individually shrink wrapped using two semi-permeable Cryovac films® (D-955 and LD-935) and a locally available LDPE film. The shrink wrapped and non-wrapped fruit were stored at 8 °C for 5 weeks and transferred to ambient conditions for subsequent ripening, to study the feasibility of alleviation of chilling injury (CI) and to determine shrink wrapping effect on fruit quality. Shrink wrapped mangoes of 'Banganapalli' and 'Alphonso' cultivars packed in D-955 (15 µm thickness) film could be stored for 5 weeks at 8 °C in fresh and unripe green condition. After storage, these cultivars respectively lost only 0.5 and 1.4 % mass in case of shrink wrapping as compared to 5.8 and 6.9 % loss in non-wrapped fruit. After removal from low temperature and unwrapping, shrink wrapped mangoes showed normal respiratory behaviour with production of CO2 and ethylene peaks (climacteric peaks) during ripening, whereas non-wrapped fruit did not show any respiratory peaks. Shrink wrapped mangoes ripened normally within a week at ambient temperature (24-32 °C and 60-70 % RH) with good surface yellow colour (reflected by hue and chroma values), edible softness, retention of nutritional quality and acceptable organoleptic quality. These quality parameters were better in fruit wrapped with D-955 film compared to LD-935 and LDPE films. Total carotenoids in terms of ß-carotene content were significantly higher in shrink wrapped fruit when compared to non-wrapped fruit. Among different shrink films, total antioxidant capacity and DPPH radical scavenging abilities were higher in LD-935 wrapped fruit in case of 'Alphonso' cultivar whereas these were on par in LD-935 and D-955 film wrapped fruit in case of 'Banganapalli' cultivar.

In vitro microbiological evaluation of novel bis pyrazolones.

Two series of bis pyrazolones (one with 3-methyl substituent and the other one with 3-amino substituent on the pyrazolone ring) were synthesized by the cyclization reaction between various hydrazides with esters/cyano esters in ethanolic medium. Structures of newly synthesized compounds were confirmed by elemental analysis, IR, (1)H NMR and mass spectral data. These compounds were screened for antibacterial and antifungal activities. The compounds of series 3 with amino substituent demonstrated better activity than the compounds of series 2 with methyl substituent on the pyrazolone ring. Compounds "e, f, c and d" showed higher antimicrobial activity than the compounds "b and a". The antimicrobial potentials of the synthesized compounds were compared with that of standards.

Synthesis, characterization and biological studies of substituted quinozoline-4-(3H)-ones containing diazepine moiety.

The synthesis and characterization of new series of 1,4-benzodiazepine derivatives have been presented. The structures were confirmed by elemental analyses, IR spectral, (1)H NMR spectral and mass spectral data. All the compounds were screened for in vitro antimicrobial and anthelmintic activities. The antibacterial activity was tested against Staphylococcus aureus (Gram positive), Bacillus cereus (Gram positive), Escherichia coli (Gram negative) and Pseudomonas aeruginosa (Gram negative). The antifungal activity was tested against Aspergillus niger and Candida albicans. All the compounds showed considerable antimicrobial activity against the microorganism studied. The significant anthelmintic activity of all novel compounds was demonstrated against Pheretima posthuma. Based on the nature of substituent present, the structure-activity correlation of novel compounds was discussed.

Falling monsoon depression frequency: a Gray-Sikka conditions perspective.

In this study, we show that the annual monsoon depression (MD) frequency making landfall on the east coast of India shows a statistically significant decreasing trend for the period 1979-2010. Importantly, about 80% of this fall is confined to the south of 20°N. To understand the plausible reason(s) for the weakening frequency of MDs in the southern Bay of Bengal in recent decades, we examine some of the seasonal average in-situ atmospheric parameters important for tropical cyclogenesis; we use various observational data from the IMD, and three atmospheric climate reanalysis datasets to account for possible quality constraints in them. Our findings suggest that the observed weakening of MD frequency south of 20°N in the Bay of Bengal since 1950s is likely due to a declining trend in the mid-tropospheric relative humidity over the Indian region. Our numerical sensitivity experiments support this finding.

Quantitative phase microscopy using dual-plane in-line digital holography.

We present detailed theoretical evaluation and thorough experimental investigation of quantitative phase imaging using our previously demonstrated dual-plane in-line digital holographic microscopy technique [Opt. Lett. 35, 3426 (2010)]. This evaluation is based on the recording of two interferograms at slightly different planes and numerically reconstructing the object information. The zero-order diffracted wave is eliminated by using the method of subtraction of average intensity of the entire hologram, and the twin-image diffracted wave is removed by Fourier domain processing of the two recorded holograms. Experiments are performed using controlled amplitude and phase objects and human muscle cells to demonstrate the potential of this technique.

Dual-channel in-line digital holographic double random phase encryption.

We present a robust encryption method for the encoding of 2D/3D objects using digital holography and virtual optics. Using our recently developed dual-plane in-line digital holography technique, two in-line digital holograms are recorded at two different planes and are encrypted using two different double random phase encryption configurations, independently. The process of using two mutually exclusive encryption channels makes the system more robust against attacks since both the channels should be decrypted accurately in order to get a recognizable reconstruction. Results show that the reconstructed object is unrecognizable even when the portion of the correct phase keys used during decryption is close to 75%. The system is verified against blind decryptions by evaluating the SNR and MSE. Validation of the proposed method and sensitivities of the associated parameters are quantitatively analyzed and illustrated.

Extensively drug-resistant tuberculosis: experience at the Tuberculosis Research Centre, Chennai, India.

Ten extensively drug-resistant tuberculosis (XDR-TB) patients were identified among 104 human immunodeficiency virus negative multidrug-resistant tuberculosis (MDR-TB) patients treated at the Tuberculosis Research Centre, Chennai, India, in two different cohorts between 1999-2003 and 2006-2007. They were managed with individualised treatment regimens. At the time of diagnosis of MDR-TB, one patient had XDR-TB and three had initial ofloxacin resistance. One patient who had had a lobectomy in addition to chemotherapy became bacteriologically negative, three died, three defaulted and the remaining three, who are bacteriologically positive, are still continuing treatment. Although based on a small number of patients, our results have not been encouraging.

Development and validation of a highly sensitive LC-MS/MS method for simultaneous quantitation of nortriptyline and 10-hydroxynortriptyline in human plasma: application to a human pharmacokinetic study.

A highly sensitive and specific LC-MS/MS method has been developed for simultaneous estimation of nortriptyline (NTP) and 10-hydroxynortriptyline (OH-NTP) in human plasma (250 µL) using carbamazepine as an internal standard (IS). LC-MS/MS was operated under the multiple reaction-monitoring mode using the electrospray ionization technique. A simple liquid-liquid extraction process was used to extract NTP, OH-NTP and IS from human plasma. The total run time was 2.5 min and the elution of NTP, OH-NTP and IS occurred at 1.44, 1.28 and 1.39 min, respectively; this was achieved with a mobile phase consisting of 20 mm ammonium acetate : acetonitrile (20:80, v/v) at a flow rate of 0.50 mL/min on a HyPURITY C(18) column. The developed method was validated in human plasma with a lower limit of quantitation of 1.09 ng/mL for both NTP and OH-NTP. A linear response function was established for the range of concentrations 1.09-30.0 ng/mL (r > 0.998) for both NTP and OH-NTP. The intra- and inter-day precision values for NTP and OH-NTP met the acceptance as per FDA guidelines. NTP and OH-NTP were stable in a battery of stability studies, i.e. bench-top, auto-sampler and freeze-thaw cycles. The developed assay was applied to a pharmacokinetic study in humans.

Identification and characterization of new impurities in rivastigmine.

Rivastigmine is a drug against Alzheimer's disease, and is a non-pharmacopoeial compound. During the preparation of rivastigmine in our laboratory, two impurities were detected and identified with a simple and sensitive reversed-phase liquid chromatography coupled with electrospray-mass spectrometry. The same impurities were also observed in commercial batches. These impurities were isolated by preparative HPLC and co-injected with rivastigmine sample to confirm the retention times in HPLC. These impurities were characterized as N,N-dimethyl-3-[1-dimethylaminoethyl]phenylcarboxylate (dimethyl-rivastigmine) and N,N-diethyl-3-[1-dimethylaminoethyl]phenylcarboxamide (diethyl-rivastigmine). Structural elucidation of these impurities by spectral data (1H NMR, 13C NMR and MS) is discussed.