A Pragmatic Approach Towards the Manufacture of Wet-White Leathers Using a Bio-Polymeric Tanning System

Content: Different tanning materials endow leather with varying colors observable in undyed leathers. Periodateoxidized starch tanned leathers have a yellow tinge or light brown color and get darker with age. The color change in situ is ascribable to iodate ions that are byproducts of periodate oxidation. Iodate ions undergo reduction to form iodine molecules that are yellow or brown in low or at higher concentrations. This study focuses on the removal of iodate ions from Dialdehyde Tapioca Starch (DTS) using a simple precipitation method. Preparation of DTS is by periodate oxidation and precipitation of iodate ions using an inorganic precipitant. The experiments for manufacturing wet-white leathers used pickled goatskins and DTS (unmodified and modified) tanning agents at various percentages based on pelt weight. Glutaraldehyde (GTA) tanning was the control. The percentage removal of iodate ions in modified DTS was 98%. Both unmodified and modified DTS had an aldehyde content of 70%. FT-IR and 1H-NMR confirmed the aldehyde groups. GTA, unmodified, and modified DTS tanned leathers had shrinkage temperatures of 80, 87, and 89°C, respectively. The physico-mechanical properties of the control and experimental leathers are comparable. GTA tanned leather had the typical brown color associated with GTA tannages. The ‘b’ color value of unmodified DTS tanned leather was high confirming yellowing of leathers upon ageing. Wet-white leather tanned with modified DTS had no discernible color change. Analysis of the spent tan liquor shows a reduction in the BOD, COD, TS, and TDS load when compared to GTA tanning system evincing the biodegradability of DTS. This study has overcome the drawback associated with periodate-oxidized starch tanning agents, viz. leather darkening over time, considering the chemical and physico-mechanical properties of the resultant leathers. The novel iodate free DTS can be scaled-up for commercial availability. Take-Away: Removal of iodate ions from periodate-oxidized starch before its use as a tanning agent is imperative to avoid leather color change over time. This study reports the successful removal of iodate ions from Dialdehyde Tapioca Starch (DTS). Wet-white leather tanned with the modified DTS had no observable color change upon ageing

Nano-Bio Aldehyde system for Leather Manufacture

Content: Development of eco-friendly chemicals from natural renewable resources are widely explored owing to its eco-acceptable and sustainability. Exploring biopolymers is the need of an hour to combat the sustainability in leather processing. Finishing is an imperative step that enhances the aesthetic appeal of the final leathers, in which, protein finishing system is known for its glazing properties. Commonly used cross-linkers as such formaldehyde and glutaraldehyde are restricted owing to biocompatibility issues. However, the use of crosslinker is inevitable for protein finish system. In the present research, nano-bio polyaldehyde (NBP) system is established through selective oxidation of starch; the size of the system is fine-tuned in the nano range for effective and efficient crosslinking through emulsion technique. The architectural design of NBP is ascertained as a good crosslinking agent for leather finishing chemicals from the characterization studies. A particle size of the NBP system found to be in the range of 80-110 nm. The surface properties of NBP treated leathers were characterized by the contact angle. The leather samples showed improved hydrophobicity nature with a contact angle of ~ 126º and also enhanced wet, rub fastness, color fastness, and adhesion strength. The study provides an insight on tunability of known biopolymers for developing sustainable technology. Take-Away: An insight on tunability of known biopolymers for developing sustainable technolog

Striding towards self sustainability using Aluminium from Tanzanian kaolin for combination Tanning system

Content: Sustainability is a key factor which control future leather manufacture. Developing several new technologies is one of the primary agenda for sustainability. However, developing countries are facing several challenges which not only limited to best practice technologies but also finding self sustainability in maximizing the available resources. In the present study, an attempt has been made to explore the potential resource of aluminium from kaolin of Pugu hills, Tanzania for combination tanning. Though, extraction of aluminium from several resources are available, there is limited literature pertaining to Tanzania resources. Moreover, the extracted aluminium is basified and studied for its tanning efficiency. Diffraction and vibrational spectroscopic studies were carried out to assess the confirmation of extracted aluminium. Combination tanning has been carried out with vegetable tannins and dialdehyde starch tanning chemicals, which are from natural resources. Leathers tanned with aluminum and wattle resulted with a shrinkage temperature of 118ºC as compared to Al-Dialdehyde starch leathers showed around 90-100ºC. Physical strength characteristics such as tensile, tear and grain crack strength met the standard norms. Grain surface of leathers are found to be smooth which has been confirmed through microscopic studies. The study provides a new insight on accomplishing self sustainability through available resources and manufacture of eco-friendly system. Take-Away: 1. Tanzania is endowed with massive kaolin rich in aluminium, which is potential for application in leather industry for sustainable development of leather industry 2. The combination tanning system using aluminium from Tanzania kaolin with wattle tannins or Dialdehyde starch imparts leather with both physical and organoleptic properties that meet the stipulated norms 3. This new tanning system provides new insight on ecofriendly tanning system for the sustainability of leather industry

Isolation of ckit-positive cardiosphere-forming cells from human atrial biopsy

There is increasing interest in developing cell-based therapies to regenerate functional muscle and blood vessels in infarcted dysfunctional myocardium, using stem cells resident in the adult heart. The objective of our study was to identify an easy and cost-effective method for the isolation and expansion of human adult cardiac-resident stem cells. The cells were isolated from right atrial biopsy samples obtained from patients with ischemic heart disease, who were undergoing coronary artery bypass grafting. Two different isolation methods, enzymatic and nonenzymatic, were employed. The cell yield and cluster formation were not significantly different with either of the techniques used for cell isolation. The nonenzymatic method is recommended because of its simplicity and lower cost compared to the enzymatic method

Survival and growth of juvenile silver pompano Trachinotus blochii (Lacepède, 1801) at different salinities in tropical conditions

The objectives of the present study were to evaluate the tolerance of juvenile silver pompano to different salinity conditions in order to determine the minimum salinity required for survival and also to study the effect of different salinities on survival and growth. Wild caught juveniles of the silver pompano Trachinotus blochii (average initial length: 4.38±0.44 cm, average initial weight: 1.6±0.09 g) were used in the experiments. The experiments were conducted in triplicate with 15 fish per tank. Control groups were maintained at 34±1 ppt. Juvenile silver pompano reared at ambient salinity (34±1ppt) were transferred directly to lower salinities (25, 15, 10, 5, 4, 3 and 1 ppt) and monitored for survival. Results indicated that the minimum salinity required for the survival of juvenile T. blochii is 4 ppt and 100% mortality was observed within 7-8 h in 1 ppt salinity. In another experiment, three salinity reduction protocols were followed and the three treatment groups were exposed to 25, 15 and 5 ppt salinity for a period of 56 days and the growth and survival were monitored. Survival and growth in terms of weight was not significantly different in the treatments from the control group except in the case of 5 ppt, which showed comparatively lower survival and specific growth rate (SGR). The results indicate that the culture of juvenile pompano might be feasible in salinities up to 15 ppt in tropical conditions

Amyloodinium ocellatum infestation in the broodstock of silver pompano Trachinotus blochii (Lacepede, 1801) and its therapeutic control

A case of amyloodiniosis caused by infestation of the dinoflagellate Amyloodinium ocellatum in the silver pompano (Trachinotus blochii) maintained for broodstock development is reported. Grossly, erosion of the operculum and excessive secretion of mucus on gills was observed. Microscopic examination of gill filaments showed the presence of trophonts. Histopathologically, gills showed erosion and necrosis of the primary and secondary lamellae. The causative organism A. ocellatum was identified based on the clinical signs as well as gross and microscopic examinations. Among many treatment methods tested, dip treatment with chloroquine phosphate (500 mg per 100 l of water) or with low saline water mixed with Oodinol 1000 were found useful in healthy maintenance of silver pompano broodstock

Investigation and validation of PV fed reduced switch asymmetric multilevel inverter using optimization based selective harmonic elimination technique

Pulse width modulation for Selective Harmonics Elimination (SHE) is mostly employed in the reduction of lower order harmonics. The PV system in this research provides input voltage to the reduced switch 31-level inverter, which is based on the Artificial Bee Colony algorithm. With a high gain DC-DC single-ended primary-inductor converter (SEPIC), the PV panel output voltage is kept constant. The Grey wolf optimization algorithm (GWO) approach is used to get the most power out PV scheme. Multi Carrier modulation, a high-frequency modulation technology, is also used in this novel design of the inverter to reduce upper order harmonics. The suggested Artificial Bee Colony (ABC) algorithm, harmonics is compared to a SHE technique based on a genetic algorithm. The hardware findings were confirmed using DSPIC30F2010 controller simulation, and the recommended system was validated using Matlab simulation

Larviculture and seed production of the silver pompano, Trachinotus blochii (Lacepede, 1801) for the first time in India

Larviculture and seed production protocols for the silver pompano Trachinotus blochii, which is one of the promising finfish species for brackishwater and marine aquaculture was developed based on six trials for the first time in India. The newly hatched larvae were stocked at a density of 20 larvae l-1 in 2 t FRP tanks with 1.5 t of seawater. Green water technique was employed during larviculture upto the weaning period. Enriched S-type rotifers were fed at a density of 10-12 nos. ml-1 until 3 day post hatch (dph) and the enriched L-type rotifers were given at a density of 6-8 nos. ml-1 from 7 dph and thereafter with enriched Artemia at a density of 3-5 nos. ml-1. Weaning started from 15 dph and by 20-25 dph metamorphosis was completed. The survival on completion of metamorphosis ranged from 10-15% and the specific growth rate in terms of length (mm) was 8% per day. The larval morphology and growth pattern are also described

Broodstock development through regulation of photoperiod and controlled breeding of silver pompano, Trachinotus blochii (Lacepede, 1801) in India

The silver pompano, Trachinotus blochii is recognised as a promising species for mariculture. In India, broodstock development, controlled breeding and seed production of silver pompano was achieved for the first time at Mandapam Regional Centre of Central Marine Fisheries Research Institute. Sub-adult fishes collected from the wild were grown in circular sea cages of 6 m diameter and 3.5 m depth. Twelve fishes were selected from a sea cage and acclimatized to laboratory conditions. Among these, four fishes (1 female and 3 males) were pre-conditioned to sexual maturity in a 10 t FRP tank with photoperiod control facility (2000 lux; 14 L: 10 D). In about 2 months, the gonads reached right stage for spawning. The brooders were administered human chorionic gonadotropin (hCG) intramuscularly, at a dosage of 350 IU kg body weight-1. A total of 5 experiments were conducted and successful spawnings were obtained resulting in the production of fertilized eggs. The time taken for spawning ranged from 30-36 h. The total number of eggs spawned ranged from 0.08 to 0.184 million. The fertilization percentage varied from 75 to 95. Freshly spawned eggs measured above 900 μ. The success obtained in all the consecutive five experiments indicated that predictable spawnings of pompano could be achieved by employing the techniques developed

Cage farming of Pompano at Mandapam

Cage farming of Pompano (Trachinotus blochii ) was experimented for the first time in India at Mandapam Regional Centre of CMFRI from the hatchery produced fingerlings. The fingerlings were stocked after nursery rearing in September 2011. The length ranged of fingerlings stocked from 6.0 to 7.0 cm and weight ranged from 12 to 14 gms. The fish were fed trash fish ad libitum twice in a day