Smart proteins as a new paradigm for meeting dietary protein sufficiency of India: a critical review on the safety and sustainability of different protein sources.

India, a global leader in agriculture, faces sustainability challenges in feeding its population. Although primarily a vegetarian population, the consumption of animal derived proteins has tremendously increased in recent years. Excessive dependency on animal proteins is not environmentally sustainable, necessitating the identification of alternative smart proteins. Smart proteins are environmentally benign and mimic the properties of animal proteins (dairy, egg and meat) and are derived from plant proteins, microbial fermentation, insects and cell culture meat (CCM) processes. This review critically evaluates the technological, safety, and sustainability challenges involved in production of smart proteins and their consumer acceptance from Indian context. Under current circumstances, plant-based proteins are most favorable; however, limited land availability and impending climate change makes them unsustainable in the long run. CCM is unaffordable with high input costs limiting its commercialization in near future. Microbial-derived proteins could be the most sustainable option for future owing to higher productivity and ability to grow on low-cost substrates. A circular economy approach integrating agri-horti waste valorization and C1 substrate synthesis with microbial biomass production offer economic viability. Considering the use of novel additives and processing techniques, evaluation of safety, allergenicity, and bioavailability of smart protein products is necessary before large-scale adoption.

N-terminal truncation of PhaCBP-M-CPF4 and its effect on PHA production.

BACKGROUND: Among the polyhydroxyalkanoate (PHA), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] is reported to closely resemble polypropylene and low-density polyethylene. Studies have shown that PHA synthase (PhaC) from mangrove soil (PhaCBP-M-CPF4) is an efficient PhaC for P(3HB-co-3HHx) production and N-termini of PhaCs influence its substrate specificity, dimerization, granule morphology, and molecular weights of PHA produced. This study aims to further improve PhaCBP-M-CPF4 through N-terminal truncation. RESULTS: The N-terminal truncated mutants of PhaCBP-M-CPF4 were constructed based on the information of the predicted secondary and tertiary structures using PSIPRED server and AlphaFold2 program, respectively. The N-terminal truncated PhaCBP-M-CPF4 mutants were evaluated in C. necator mutant PHB-4 based on the cell dry weight, PHA content, 3HHx molar composition, molecular weights, and granule morphology of the PHA granules. The results showed that most transformants harbouring the N-terminal truncated PhaCBP-M-CPF4 showed a reduction in PHA content and cell dry weight except for PhaCBP-M-CPF4 G8. PhaCBP-M-CPF4 G8 and A27 showed an improved weight-average molecular weight (Mw) of PHA produced due to lower expression of the truncated PhaCBP-M-CPF4. Transformants harbouring PhaCBP-M-CPF4 G8, A27, and T74 showed a reduction in the number of granules. PhaCBP-M-CPF4 G8 produced higher Mw PHA in mostly single larger PHA granules with comparable production as the full-length PhaCBP-M-CPF4. CONCLUSION: This research showed that N-terminal truncation had effects on PHA accumulation, substrate specificity, Mw, and granule morphology. This study also showed that N-terminal truncation of the amino acids that did not adopt any secondary structure can be an alternative to improve PhaCs for the production of PHA with higher Mw in mostly single larger granules.

Efficient production of polyhydroxybutyrate using lignocellulosic biomass derived from oil palm trunks by the inhibitor-tolerant strain Burkholderia ambifaria E5-3.

Lignocellulosic biomass is a valuable, renewable substrate for the synthesis of polyhydroxybutyrate (PHB), an ecofriendly biopolymer. In this study, bacterial strain E5-3 was isolated from soil in Japan; it was identified as Burkholderia ambifaria strain E5-3 by 16 S rRNA gene sequencing. The strain showed optimal growth at 37 °C with an initial pH of 9. It demonstrated diverse metabolic ability, processing a broad range of carbon substrates, including xylose, glucose, sucrose, glycerol, cellobiose, and, notably, palm oil. Palm oil induced the highest cellular growth, with a PHB content of 65% wt. The strain exhibited inherent tolerance to potential fermentation inhibitors derived from lignocellulosic hydrolysate, withstanding 3 g/L 5-hydroxymethylfurfural and 1.25 g/L acetic acid. Employing a fed-batch fermentation strategy with a combination of glucose, xylose, and cellobiose resulted in PHB production 2.7-times that in traditional batch fermentation. The use of oil palm trunk hydrolysate, without inhibitor pretreatment, in a fed-batch fermentation setup led to significant cell growth with a PHB content of 45% wt, equivalent to 10 g/L. The physicochemical attributes of xylose-derived PHB produced by strain E5-3 included a molecular weight of 722 kDa, a number-average molecular weight of 191 kDa, and a polydispersity index of 3.78. The amorphous structure of this PHB displayed a glass transition temperature of 4.59 °C, while its crystalline counterpart had a melting point of 171.03 °C. This research highlights the potential of lignocellulosic feedstocks, especially oil palm trunk hydrolysate, for PHB production through fed-batch fermentation by B. ambifaria strain E5-3, which has high inhibitor tolerance.

Complete genome sequence of Aquitalea pelogenes USM4 (JCM19919), a polyhydroxyalkanoate producer.

Polyhydroxyalkanoate (PHA) is a type of biopolymer produced by most bacteria and archaea, resembling thermoplastic with biodegradability and biocompatibility features. Here, we report the complete genome of a PHA producer, Aquitalea sp. USM4, isolated from Perak, Malaysia. This bacterium possessed a 4.2 Mb circular chromosome and a 54,370 bp plasmid. A total of 4067 predicted protein-coding sequences, 87 tRNA genes, and 25 rRNA operons were identified using PGAP. Based on ANI and dDDH analysis, the Aquitalea sp. USM4 is highly similar to Aquitalea pelogenes. We also identified genes, including acetyl-CoA (phaA), acetoacetyl-CoA (phaB), PHA synthase (phaC), enoyl-CoA hydratase (phaJ), and phasin (phaP), which play an important role in PHA production in Aquitalea sp. USM4. The heterologous expression of phaC1 from Aquitalea sp. USM4 in Cupriavidus necator PHB-4 was able to incorporate six different types of PHA monomers, which are 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), 4-hydroxybutyrate (4HB), 5-hydroxyvalerate (5HV), 3-hydroxyhexanoate (3HHx) and isocaproic acid (3H4MV) with suitable precursor substrates. This is the first complete genome sequence of the genus Aquitalea among the 22 genome sequences from 4 Aquitalea species listed in the GOLD database, which provides an insight into its genome evolution and molecular machinery responsible for PHA biosynthesis.

Characterization of P(3HB) from untreated raw palm oil mill effluent using Azotobacter vinelandii ΔAvin_16040 lacking S-layer protein.

The production of poly(3-hydroxybutyrate) [P(3HB)] from untreated raw palm oil mill effluent (urPOME), the first wastewater discharge from crude palm oil extraction, is discussed. The mutant strain Azotobacter vinelandii ΔAvin_16040, which lacks the S-layer protein but has a better P(3HB) synthesis capability than the wild type strain ATCC 12,837, was chosen for this study. UrPOME substrate, with high biological oxygen demand (BOD), chemical oxygen demand (COD) and suspended solids, was used without pre-treatment. DSMZ-Azotobacter medium which was devoid of laboratory sugar(s) was used as the basal medium (BaM). Initially, Azotobacter vinelandii ΔAvin_16040 generated 325.5, 1496.3, and 1465.7 mg L-1 of P(3HB) from BaM with 20% urPOME, 2BaM with 20% urPOME and 20 g L-1 sucrose, and 2BaM with 20% urPOME and 2 mL L-1 glycerol, respectively. P(3HB) generation was enhanced by nearly tenfold using statistical optimization, resulting in 13.9 g L-1. Moreover, the optimization reduced the compositions of mineral salts and sugar in the medium by 48 and 97%, respectively. The urPOME-based P(3HB) product developed a yellow coloration most possibly attributed to the aromatic phenolics content in urPOME. Despite the fact that both were synthesised by ΔAvin_16040, thin films of urPOME-based P(3HB) had superior crystallinity and tensile strength than P(3HB) produced only on sucrose. When treated with 10 and 50 kGy of electron beam irradiation, these P(3HB) scissioned to half and one-tenth of their original molecular weights, respectively, and these cleavaged products could serve as useful base units for specific polymer structure construction.

Effect of decomposing oil palm trunk fibers on plant growth and soil microbial community composition.

Oil palm trunks (OPT) are logged for replantation and the fiber residues are disposed of into the palm plantation area. The fiber residues are expected to increase soil fertility through recycling of carbon and minerals via fiber decomposition. This study investigated the effects of OPT fiber disposal and other lignocellulosic biomass on plant growth and microbial diversity in the soil environment. Four treatment plots were tested: (A) soil+OPT fiber (1:20), (B) soil+sugarcane bagasse (1:20), (C) soil+cellulose powder (1:20), and (D) unamended soil as a negative control. Low plant height, decreased chlorophyll content, and low biomass was observed in corn grown on soil mixed with OPT fiber, cellulose, and sugarcane bagasse, when compared with those of the control. The plants grown with OPT fiber were deficient in total nitrogen and magnesium when compared with those without fiber amendment, which suggested that nitrogen and minerals in soil might be taken up by changing microflora because of the OPT fibers presence. To confirm differences in the soil microflora, metagenomics analysis was performed on untreated soil and soil from each lignocellulose treatment. The microflora of soils mixed with OPT fiber, cellulose and sugarcane bagasse revealed substantial increases in bacteria such as families Cytophagaceae and Oscillospiraceae, and two major fungal genera, Trichoderma and Trichocladium, that are involved in lignocellulose degradation. OPT fiber resulted in a drastic increase in the ratios and amounts of Trichocladium in the soil when compared with those of cellulose and sugarcane bagasse. These results indicate that unregulated disposal of OPT fiber into plantation areas could result in nutrient loss from soil by increasing the abundance of microorganisms involved in lignocellulose decomposition.

Electrospun (Nickel and palladium) tin(IV) oxide/polyaniline/polyhydroxy-3-butyrate biodegradable nanocomposite fibers for low temperature ethanol gas sensing.

Tin (IV) oxide (SnO2) nanostructures are regarded as one of the most popular materials for conventional gas sensors, due to their high surface area and fast response in regard to most reducing and oxidizing gases. However, their high operating temperature (>200 °C) leads to high power consumption and limits their applications. Here, a new nanocomposite fiber materials, consisting of undoped and doped (nickel and palladium) SnO2 nanorods, polyaniline (PANI), and polyhydroxy-3-butyrate (P3HB) are synthesized via the hydrothermal method,followed by an in situ polymerization and electrospinning technique. The as-synthesized nanocomposites are tested using ethanol gas at different operating temperatures: 25 °C (room temperature), 60 °C, and 80 °C. The results reveal that all samples began to show a response at 80 °C. Pd:SnO2/PANI/P3HB nanocomposite fiber sensors demonstrate a relatively higher response than that of SnO2/PANI/P3HB and Ni:SnO2/PANI/P3HB nanocomposite sensors. At 80 °C , the Pd:SnO2/PANI/P3HB nanocomposite sensor records a response (R0/Rg ) of 1610, with a response time (Tres) of 90 s and a recovery time (Trec ) of 9 min in relation to 1000 ppm ethanol gas in N2. The sensor also displays a good level of response (R0/Rg = 200) at a low concentration level (50 ppm) of ethanol gas. Structural and chemical characterizations indicate that the ethanol gas sensing performance of Pd:SnO2/PANI/P3HB nanocomposite fibers can mainly be attributed to the p-n heterojunction, fiber geometry, and one-dimensional structure of SnO2 and to the presence of the Pd catalyst. This bio-nanocomposite fiber has the potential to be a breakthrough material in biodegradable low temperature ethanol sensing applications.

Fabrication of biopolymer polyhydroxyalkanoate/chitosan and 2D molybdenum disulfide-doped scaffolds for antibacterial and biomedical applications.

Antibiotic resistance in pathogenic bacteria is a major health challenge, as Infectious Diseases Society of America (IDSA) has recognized that the past simply drugs susceptible pathogens are now the most dangerous pathogens due to their nonstop growing resistance towards conventional antibiotics. Therefore, due to the emergence of multi-drug resistance, the bacterial infections have become a serious global problem. Acute infections feasibly develop into chronic infections because of many factors; one of them is the failure of effectiveness of antibiotics against superbugs. Modern research of two-dimensional nanoparticles and biopolymers are of great interest to attain the intricate bactericidal activity. In this study, we fabricated an antibacterial nanocomposite consisting of representative two-dimensional molybdenum disulfide (2D MoS2) nanoparticles. Polyhydroxyalkanoate (PHA) and chitosan (Ch) are used to encapsulate MoS2 nanoparticles into their matrix. This study reports the in vitro antibacterial activity and host cytotoxicity of novel PHA-Ch/MoS2 nanocomposites. PHA-Ch/MoS2 nanocomposites were subjected to time-dependent antibacterial assays at various doses to examine their antibacterial activity against multi-drug-resistant Escherichia coli K1 (Malaysian Type Culture Collection 710859) and methicillin-resistant Staphylococcus aureus (MRSA) (Malaysian Type Culture Collection 381123). Furthermore, the cytotoxicity of nanocomposites was examined against spontaneously immortalized human keratinocyte (HaCaT) cell lines. The results indicated significant antibacterial activity (p value < 0.05) against E. coli K1 and MRSA. In addition, PHA-Ch/MoS2 showed significant host cytocompatibility (p < 0.05) against HaCaT cells. The fabricated PHA-Ch/MoS2 nanocomposites have demonstrated effective antibacterial activity against both Gram-positive and -negative bacteria and exhibited better biocompatibility. Finally, PHA-Ch/MoS2 nanocomposites are shown to be suitable for antibacterial applications and also hold potential for further biomedical studies. Graphical Abstract.

Complete Genome Sequence of a Novel Polyhydroxyalkanoate (PHA) Producer, Jeongeupia sp. USM3 (JCM 19920) and Characterization of Its PHA Synthases.

A novel polyhydroxyalkanoate (PHA)-producing bacterium, Jeongeupia sp. USM3 (JCM 19920) was isolated from the limestone soil at Gua Tempurung, Perak, Malaysia. This is the first report on the complete genome sequence for the genus Jeongeupia. This genome consists of a circular chromosome with a size of 3,788,814 bp and contains 3557 genes. Two PHA synthase (phaC) genes encoding for the key enzyme in the polymerization of PHA monomers and other PHA-associated genes were identified from the genome. Phylogenetic analysis of the PhaC protein sequences has revealed that both PhaC1 and PhaC2 of Jeongeupia sp. USM3 are categorized as Class I PHA synthases with 56% similarity to each other. Both of the PHA synthase genes of this isolate were cloned and heterologously expressed in a PHA mutant strain Cupriavidus necator PHB-4. The ability of the transformants to accumulate PHA showed that both PhaC1 and PhaC2 were functional.

Bioprospecting potential of microbial communities in solid waste landfills for novel enzymes through metagenomic approach.

Landfills are repository for complex microbial diversity responsible for bio-degradation of solid waste. To elucidate this complexity, samples from three different landfill sites of North India (sample V: Bhalswa near Karnal byepass road, New Delhi, India; sample T: Chandigarh, India and sample S3: Una, H.P., India) were analyzed using metagenomic approach. Selected landfill sites had different geographical location, varied in waste composition, size of landfill and climate zone. For comparison, one sample from high altitude (sample J) having less human interference was taken in this study. The aim of this study was to explore microbial diversity of communities responsible for degradation of landfill. Samples were characterized by 16S rRNA gene sequencing. Data from three landfill sites showed abundance of phylum Proteobacteria while less contaminated sample from high altitude showed abundance of phylum Cholroflexi followed by phylum Proteobacteria. The most abundant genus was unknown suggesting that these landfills could be repository for various novel bacterial communities. Sample T was relatively more active in terms of microbial activity. It was relatively abundant in enzymes responsible for dioxin degradation, styrene degradation, steroid degradation, streptomycin biosynthesis, carbapenem biosynthesis, monobactam biosynthesis, furfural degradation pathways while sample J was predicted to be enriched in plant cell wall degrading enzymes. Co-occurrence analysis revealed presence of complex interaction networks between microbial assemblages responsible for bio-degradation of hydrocarbons. The data provides insights about synergetic interactions and functional interplay between bacterial communities in different landfill sites which could be further exploited to develop an effective bioremediation process.

Atmospheric cold plasma (ACP) treatment improved in-package shelf-life of strawberry fruit.

The aim of this study was to investigate the effect of atmospheric cold plasma (ACP) treatment on the microbial inactivation, physicochemical properties, and shelf-life of strawberry fruit with its extended in-package storage at room (25 °C) and refrigerated (4 °C) temperature. ACP treatment of 10, 15 and 30 min was studied on strawberry fruit using a dielectric barrier discharge (DBD) at 60 kV with an input voltage of 260 V at 50 Hz. The shelf-life of ACP treated strawberry was extended to 5 days at 25 °C and 9 days at 4 °C in sealed ACP package. However, non-treated packaged strawberry was degraded in 2 days. ACP treatment of 15 min resulted in 2 log reduction of microbial load and enhanced the concentration of chlorogenic acid, hyprin, phloretin, vanillin, gallic acid, 4-hydroxybenzaldehyde and rutin during in-package storage of 5 day (~ 120 h) at 25 °C with respect to control (p < 0.05). In addition, ACP treatment of 15 min at 60 kV was also found to increase the total phenolic content and antioxidant activity. However, total soluble solids, pH and moisture were not affected with ACP treatment (p > 0.05). Therefore, ACP treatment of 15 min with in-package storage of 5 days (~ 120 h) was found to be advantageous for increasing the shelf-life and functional quality of strawberry fruit.

PHA synthase (PhaC): interpreting the functions of bioplastic-producing enzyme from a structural perspective.

Polyhydroxyalkanoates (PHAs) are biopolymers synthesized by a wide range of bacteria, which serve as a promising candidate in replacing some conventional petrochemical-based plastics. PHA synthase (PhaC) is the key enzyme in the polymerization of PHA, and the crystal structures were successfully determined using the catalytic domain of PhaC from Cupriavidus necator (PhaCCn-CAT) and Chromobacterium sp. USM2 (PhaCCs-CAT). Here, we review the beneficial mutations discovered in PhaCs from a structural perspective. The structural comparison of the residues involved in beneficial mutation reveals that the residues are near to the catalytic triad, but not inside the catalytic pocket. For instance, Ala510 of PhaCCn is near catalytic His508 and may be involved in the open-close regulation, which presumably play an important role in substrate specificity and activity. In the class II PhaC1 from Pseudomonas sp. 61-3 (PhaC1Ps), Ser325 stabilizes the catalytic cysteine through hydrogen bonding. Another residue, Gln508 of PhaC1Ps is located in a conserved hydrophobic pocket which is next to the catalytic Asp and His. A class I, II-conserved Phe420 of PhaCCn is one of the residues involved in dimerization and its mutation to serine greatly reduced the lag phase. The current structural analysis shows that the Phe362 and Phe518 of PhaC from Aeromonas caviae (PhaCAc) are assisting the dimer formation and maintaining the integrity of the core beta-sheet, respectively. The structure-function relationship of PhaCs discussed in this review will serve as valuable reference for future protein engineering works to enhance the performance of PhaCs and to produce novel biopolymers.

Changes in ocular surface status after phacoemulsification in patients with senile cataract.

AIM: To evaluate the signs and symptoms of dry eye after phacoemulsification; effects on the status of ocular surface using impression cytology; and associated risk factors. METHODS: Prospective study included 50 eyes (50 patients) with no dry eye signs or symptoms, who underwent clear corneal phacoemulsification for senile cataract. Dry eye indices used included Ocular Surface Disease Index scoring, Schirmer I test, tear break up time, tear meniscus height, corneal fluorescein staining, lissamine green staining and goblet cell density (GCD) with the help of impression cytology. Primary outcome measures included post-operative changes in the dry eye indices. Secondary outcome measures included correlation of the dry eye signs and symptoms with various risk factors. RESULTS: Aggravation of both the signs and symptoms of dry eye were noted in immediate post-operative period. The sharp deterioration was followed by a recovering trend towards the end of sixth week. A decrease in GCD was also noted. Risk factors for deterioration include age, duration of exposure to microscope light and effective phacoemulsification time. Diabetic status, socio-economic status and site of incision did not have any effect on dry eye status. CONCLUSION: There is a transient deterioration of "dry eye" status post-phacoemulsification. The patients should be carefully counselled about the evanescent nature of the disease. Incision can be given at the site of high corneal curvature to neutralize astigmatism without any fear of inducing dry eye. Minimum light exposure and ultrasound energy should be used during the surgery.

A novel biological recovery approach for PHA employing selective digestion of bacterial biomass in animals.

Polyhydroxyalkanoate (PHA) is a family of microbial polyesters that is completely biodegradable and possesses the mechanical and thermal properties of some commonly used petrochemical-based plastics. Therefore, PHA is attractive as a biodegradable thermoplastic. It has always been a challenge to commercialize PHA due to the high cost involved in the biosynthesis of PHA via bacterial fermentation and the subsequent purification of the synthesized PHA from bacterial cells. Innovative enterprise by researchers from various disciplines over several decades successfully reduced the cost of PHA production through the efficient use of cheap and renewable feedstock, precisely controlled fermentation process, and customized bacterial strains. Despite the fact that PHA yields have been improved tremendously, the recovery and purification processes of PHA from bacterial cells remain exhaustive and require large amounts of water and high energy input besides some chemicals. In addition, the residual cell biomass ends up as waste that needs to be treated. We have found that some animals can readily feed on the dried bacterial cells that contain PHA granules. The digestive system of the animals is able to assimilate the bacterial cells but not the PHA granules which are excreted in the form of fecal pellets, thus resulting in partial recovery and purification of PHA. In this mini-review, we will discuss this new concept of biological recovery, the selection of the animal model for biological recovery, and the properties and possible applications of the biologically recovered PHA.

Correction to: Cupriavidus malaysiensis sp. nov., a novel poly(3-hydroxybutyrate-co-4-hydroxybutyrate) accumulating bacterium isolated from the Malaysian environment.

In the original publication of the article, it was noted that Fig. 1 present an image of Cupriavidus malaysiensis strain USMAHM13 and not of strain USMAA1020, as indicated in the figure legend. The image in the original version is thus noted to serve as a record of strain USMAHM13 and the corrected version of Fig. 1 is reprinted below.

Cupriavidus malaysiensis sp. nov., a novel poly(3-hydroxybutyrate-co-4-hydroxybutyrate) accumulating bacterium isolated from the Malaysian environment.

Bacterial classification on the basis of a polyphasic approach was conducted on three poly(3 hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] accumulating bacterial strains that were isolated from samples collected from Malaysian environments; Kulim Lake, Sg. Pinang river and Sg. Manik paddy field. The Gram-negative, rod-shaped, motile, non-sporulating and non-fermenting bacteria were shown to belong to the genus Cupriavidus of the Betaproteobacteria on the basis of their 16S rRNA gene sequence analyses. The sequence similarity value with their near phylogenetic neighbour, Cupriavidus pauculus LMG3413T, was 98.5%. However, the DNA-DNA hybridization values (8-58%) and ribotyping analysis both enabled these strains to be differentiated from related Cupriavidus species with validly published names. The RiboPrint patterns of the three strains also revealed that the strains were genetically related even though they displayed a clonal diversity. The major cellular fatty acids detected in these strains included C15:0 ISO 2OH/C16:1 ω7c, hexadecanoic (16:0) and cis-11-octadecenoic (C18:1 ω7c). Their G+C contents ranged from 68.0  to 68.6 mol%, and their major isoprenoid quinone was Ubiquinone Q-8. Of these three strains, only strain USMAHM13 (= DSM 25816 = KCTC 32390) was discovered to exhibit yellow pigmentation that is characteristic of the carotenoid family. Their assembled genomes also showed that the three strains were not identical in terms of their genome sizes that were 7.82, 7.95 and 8.70 Mb for strains USMAHM13, USMAA1020 and USMAA2-4, respectively, which are slightly larger than that of Cupriavidus necator H16 (7.42 Mb). The average nucleotide identity (ANI) results indicated that the strains were genetically related and the genome pairs belong to the same species. On the basis of the results obtained in this study, the three strains are considered to represent a novel species for which the name Cupriavidus malaysiensis sp. nov. is proposed. The type strain of the species is USMAA1020T (= DSM 19416T = KCTC 32390T).

Production and recovery of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) from biodiesel liquid waste (BLW).

Polyhydroxyalkanoates (PHAs) has been paid great attention because of its useful thermoplastic properties and complete degradation in various natural environments. But, at industrial level, the successful commercialization of PHAs is limited by the high production cost due to the expensive carbon source and recovery processes. Pseudomonas mendocina PSU cultured for 72 h in mineral salts medium (MSM) containing 2% (v/v) biodiesel liquid waste (BLW) produced 79.7 wt% poly(3-hydroxybutyrate) (PHB) at 72 h. In addition, this strain produced 43.6 wt% poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with 8.6 HV mol% at 60 h when added with 0.3% sodium propionate. The synthesized intracellular PHA granules were recovered and purified by the recently reported biological method using mealworms. The weight average molecular weight (Mw ) and number average molecular weight (Mn ) of the biologically extracted PHA were higher than that from the chloroform extraction with comparable melting temperature (Tm ) and high purity. This study has successfully established a low-cost process to synthesize PHAs from BLW and subsequently confirmed the ability of mealworms to extract PHAs from various kinds of bacterial cells.

Indications and graft survival analysis in optical penetrating keratoplasty in a tertiary care center in North India: a 5-year study.

PURPOSE: To study the indications and variables correlating with graft survival in optical penetrating keratoplasty in a tertiary care hospital in north India. PARTICIPANTS: All patients who underwent optical keratoplasty, except those undergoing lamellar grafts, tectonic grafts transplants and penetrating keratoplasty done for therapeutic purposes were included in the study. Patients with follow-up less than 2 years were excluded from the study. MATERIALS AND METHODS: Data were obtained by reviewing the records of 101 patients who underwent optical penetrating keratoplasty from 2008 to 2013 for various indications. RESULTS: Out of 101 patients who underwent optical penetrating keratoplasty, 71 were males and 30 were females. The mean age of the recipient was 48.53 years with range 1-82 years. The main indications were previous failed graft (29.7%), healed keratitis except HSV (15.8%), pseudophakic or aphakic bullous keratopathy (14.8%), corneal dystrophies/degenerations (12.9%), adherent leucoma (9.9%), post-HSV scars (8.9%), and others like anterior staphyloma, congenital corneal opacities, buphthalmos and keratoconus (7.9%). The graft survival rate was 67.33% at 1-year follow-up and 59.4% at 2-year follow-up. The mean survival time of the grafts was 22.42 months. The mean time for graft failure was 7.12 (±0.9) months. CONCLUSION: One- and 2-year survival of grafts at our center is lower as compared to western studies, probably due to higher percentage of poor prognosis indications for surgery and a relative scarcity of excellent-quality donor corneas.

Machine vision based alternative testing approach for physical purity, viability and vigour testing of soybean seeds (Glycine max).

The conventional methods for seed quality testing have several limitations as they involve visual assessment and are destructive. In this context, a study was performed to assess the suitability of non-contact, non-destructive type imaging techniques such as visible imaging and X-ray imaging for conducting physical purity, viability and vigour tests of soybean seeds. The seeds that appeared healthy in external surface examination using visible tests as well as in internal assessment using X-ray tests were classified as sound seeds while the other seeds were marked as not-sound seeds. The obtained results were then correlated with the results of the standard germination tests. The high correlation results between the imaging tests and the standard conventional germination tests indicate the effectiveness and usability of the proposed image analysis based technique as an attractive alternative to the existing quality assessment methods for soybean seeds.

Tomato processing byproduct valorization in bread and muffin: improvement in physicochemical properties and shelf life stability.

Tomato processing industry generates huge waste like tomato skin, seed, and pulp which creates environmental issues. Since tomato pomace contains bioactive compounds and pigments, present study was conducted to investigate the effect of tomato pomace addition on physicochemical characteristics and shelf-life stability of the developed bread and muffin. Refined flour was partially substituted with 35 and 40% tomato pomace in bread and muffin, respectively. Tomato pomace addition in bread and muffin was observed to significantly (p < 0.05) increase the dietary fiber, vitamin C, antioxidant activity and minerals (Na, K, Mg, Ca, Fe). The color parameters for bread and muffins were quantified in terms of L* (lightness), a* (redness/greenness) and b* (yellowness/blueness). There was an increase in a* and b*, while L* values decreased. Tomato based bread and muffin were found to possess softer texture as compared to control products. Microbial study has depicted the enhanced shelf-life of tomato based bread and muffin. Shelf life of preservative added tomato based bread was 8 days and muffins were 12 days. Tomato pomace could be a very useful commodity for incorporation into bread and muffin to have a complete nutritive food product.