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Association between the gastric microbiota and histopathological changes in the gastric mucosa.
Get PDFDespite the hostile environment of the stomach, recent studies suggest that gastric
mucosa has a core microbiome. This raises the possibility of a pathogenic role of non
H. pylori organisms in the gastric mucosa which may contribute to dyspeptic
symptoms. Thus, this study investigates bacterial diversity of the stomach using PCR
DGGE techniques to provide information on the possible role of other non-H. pylori
microorganisms in causing gastric pathology. For the first time in Sri Lanka it was
reported the presence of yeast species majority being Candida albicans in the gastric
mucosa and its presence was significantly associated with gastric pathology. A diverse
interpersonal variation of bacteria in the gastric mucosa was observed.
Histopathological grading increased in the presence of low bacterial diversity which
suggest disruption of the normal gastric microbiota with the establishment of
pathogenic microorganisms
Biodiesel production through the transesterification of waste cooking oil over typical heterogeneous base or acid catalysts
Get PDFFor the production of biodiesel from waste cooking oil with an acid value of 1.86 mg
KOH/g, five heterogeneous catalysts—Ba(OH)2
, CaO, MgO, ZnO, and AlCl3—were employed. To
optimize the reaction parameters of each catalyst, the influence of crucial process variables, such
as catalyst loading, methanol-to-oil ratio, and reaction duration, was investigated. In addition, the
effect of acetone as a cosolvent toward the progress of biodiesel production and the reusability of the
heterogeneous catalysts were also examined, and the data were statistically evaluated with a 95%
confidence level. Ba(OH)2 performed exceptionally well, with a 92 wt.% biodiesel yield, followed by
CaO with an 84 wt.% yield. However, none of the results for MgO, ZnO, or AlCl3 were adequate.
In addition, regardless of the type of catalyst utilized, adding 20 vol.% acetone to the biodiesel
manufacturing process led to an increase in output. Furthermore, every heterogeneous catalyst was
reusable, but only Ba(OH)2 and CaO produced a significant yield until the third cycle. The other
catalysts did not produce yields of any significance
Effect of sodium alginate - rice bran encapsulation on viability and storage stability of lactobacillus rhamnosus GG in cold bael (Aegle Marmelos l. Correa) flower drink
Get PDFPlant-based probiotic drinks have recently been developed for vegetarians and people
with lactose intolerance, and dairy allergy. They provide health benefits due to the
presence of both probiotics and phytochemicals. The availability of anti-microbial and
antioxidant properties in herbal drinks reduces the viability of probiotics and
microencapsulation can be used to improve the probiotic survival in herbal drinks. The
study intended to investigate the impact of Sodium Alginate encapsulation with rice
bran extracts including Kalu Heenati, Rathu Nadu (BG406), and Sudu Nadu (BG94/1),
on the viability of Lactobacillus rhamnosus GG (LGG) in a cold Bael flower beverage.
The encapsulation efficiency, size, shape, and bulk density of the encapsulated LGG
were investigated. Then Bael flower drink was developed by incorporating
encapsulated LGG (SA+2% BG406) with the highest encapsulation efficiency. The
probiotic potential of the selected encapsulated LGG (SA+ 2% BG406) was determined
after freeze-drying and when exposed to simulated gastrointestinal conditions. Color,
total phenolic content, total antioxidant capacity, tannin content, total plate count, and
viability of encapsulated LGG of herbal drinks were performed weekly over 21 days at
4°C. Sensory attributes were evaluated by using the same/different test. SA+ 2%
BG406 beads had shown a reduction in 1.79 log cycles after freeze-drying. When
exposed to simulated gastrointestinal conditions, 2.43 log cycles were reduced. The
encapsulation efficiency and diameter of the beads were increased, while the sphericity
and bulk density were reduced when concentrations of rice brans were increased.
Results of the properties of Beal flower drinks suggested that there was significantly
higher preservation in color (∆E*=2.5), total phenolic content (116.47 ppm), total
antioxidant capacity (0.00151 molL-1), and tannin content (1017.52 ppm) in drinks with
encapsulated LGG compared to the drinks with non-encapsulated LGG during storage
(p < 0.05). The viability of encapsulated LGG in the Bael drink had remained at a
beneficial level (7.18 log CFU/mL) while the drink with non-encapsulated LGG had
viability in 4.88 log CFU/mL. Encapsulated LGG did not exert any negative impact on
the sensory attributes including colour, taste, and appearance of the Bael flower drink.
This study shows that the application of encapsulated LGG with Sodium Alginate and
rice bran could be a promising strategy for developing an herbal probiotic drink
Production of low aromatic white spirits (laws) from kerosene oil using chitosan
Get PDFLow aromatic white spirit (LAWS) is a widely used solvent in industrial and
commercial applications due to its reduced aromatic hydrocarbon content, making it
safer for both health and the environment compared to solvents with higher aromatic
levels. LAWS is particularly crucial in the paint industry, as its low aromaticity ensures
the desired color in paints, preventing issues with pigment performance. It is derived
from the distillation of petroleum crude oil and shares similarities in chemical
composition and physical properties with kerosene, allowing for production from high
aromatic fractions through dearomatization processes. A spirit sample was acquired by
subjecting kerosene vapor (100 mL) to treatment with chitosan extracted from prawn
shell waste (10 grams) at room temperature. The dearomatization process was evaluated
using FT-IR analysis, while the chitosan material underwent characterization through
FT-IR and SEM analyses. Based on the FT-IR results, the intensity of the characteristic
peak associated with CH bonds connected to aromatic rings decreased significantly,
while the intensity of aliphatic CH bonds remained relatively constant. Since directly
measuring peak intensity isn't suitable for quantitative FT-IR analysis, the peak
intensity ratio between aromatic and aliphatic CH bonds was considered. This analysis
revealed a significant removal of aromatic groups in the treated kerosene. Additionally,
the further reduction in the intensity of the characteristic carbon-carbon double bond in
the FT-IR spectrum obtained from treated kerosene also confirmed the successful
dearomatization of kerosene upon treatment with chitosan. The research demonstrates
that chitosan effectively dearomatizes kerosene oil, resulting in the production of
LAWS. This approach is both environmentally friendly and economically efficient.
Keywords – Kerosene oil, Chitosan, and LAWS
Characterization of Sri Lankan maize (zea mays l.) accessions using ssr markers associated with insect-resistant traits
Get PDFMaize genetic diversity is utmost to develop new varieties conferred with favorable agronomic traits.
Landraces are priceless resources that can serve to strengthen crop breeding programs. Hence, this
study aimed to characterize 19 Sri Lankan maize landraces and one elite commercial variety Bhadra
using SSR markers linked with insect-resistant traits. Using established procedures, genomic DNA
extraction was done from immature maize leaves and PCR was performed utilizing bnlg1017,
bnlg339, umc1021, umc1187, bnlg1346, bnlg1588, bnlg1556, umc1178, nc134, umc1688 and
umc1045 primers. GenAlex and DARwin software were used for the data analysis. According to the
results, a sum of 77 alleles was amplified with the maximum number of observed (13) and effective
(11.28) alleles for bnlg1588. The highest gene diversity and PIC values were recorded in bnlg1588
(0.911 and 0.904 respectively), while the lowest was in umc1045 (0.640 and 0.581 respectively). Out
of the total SSR primers used, bnlg1588, bnlg339, bnlg1346, and bnlg1017 linked with FAW-resistant
traits were found to be more informative based on their genetic diversity parameters. The accessions
SEU7, SEU11, SEU16, and SEU20 showed more genetic diversity compared to Bhadra, whereas SEU17
showed the lowest diversity. The dendrogram divided the 20 maize accessions into two main clusters
with the mean similarity of 0.752. Similarly, the principle coordinate analysis explained 40.63 % of
the genetic variation and grouped the maize accessions into two. Considering the genetic diversity
parameters, the accessions SEU6 and SEU7 from cluster I and SEU9, SEU11, SEU16, and SEU20 from
cluster II could be utilized for strategic maize breeding programs in Sri Lanka
Use of antagonistic Yeast in controlling anthracnose caused by colletotrichum gloeosporioides in papaya in Sri Lanka
Get PDFAnthracnose, which is caused by Colletotrichum gloeosporioides, is one of the most prevalent
papaya diseases in Sri Lanka. Although it is controlled by a variety of chemical fungicides, the
possibility of the pathogen developing a chemical resistance and consumer demands made the
need for a biocontrol technique to manage this disease. Additionally, using biocontrol
techniques that have been developed in other countries may have negative effects on
nontargeted organisms. Therefore, this study intended to assess the antagonistic yeasts' potential
to inhibit the growth of C. gloeosporioides in papaya in Sir Lankan context. Four types of yeasts
were isolated from Carica papaya L. (Papaya) leaf surfaces, Psidium guajava L. (Guava) leaf
surfaces, Cocos nucifera (Coconut) water and Baker’s Yeast solution (Sacchsromyces
cerevisiae)(Y162, Y234, Y342, and Y467 respectively) were isolated. C. gloeosporioides was
isolated from diseased papaya fruits and morphologically identified based on their colony
characteristics and spore characteristics. The dual culture assay was used to examine the
antagonistic activity. Commercial antibiotic, Fluconazole was used as the positive control. All
four yeast isolates had shown significant antagonistic activity against C. gloeosporioides (One
way ANOVA, P <0.05), which was even higher than the positive control. The highest The
Percent Inhibition of Radial Growth (PIRG %) was observed with Y162 yeast variety
(59.3±2.0). In Vivo, the variety Y162 caused 66.2% reductions in disease incidence. According
to these findings antagonistic yeast Y162 could be utilized as a possible biological control agent
against the anthracnose disease caused by C. gloeosporioides in papaya in Sri Lanka
An analysis of success factors of digital entrepreneurs in Western Province, Sri Lanka
Get PDFThe nature of uncertainty in entrepreneurial activities and methods for
coping with uncertainty have changed as a result of digital technology. Many
businesses in Sri Lanka have failed within a few years of their founding, despite the
efforts of entrepreneurs. There has been little study done on the prospects, difficulties,
and key success elements of digital entrepreneurship. The goal of this study was to
pinpoint the key success factors (CSFs) that govern how well digital business is
implemented. The literature review identified relationship competency, IT business
process integration competency, and competency in digital business strategy as
antecedents of E-business success. Data was gathered by utilizing a questionnaire
and was acquired using quantitative research techniques. E-business success was
measured using reflective and formative items on e-efficiency, e-business lock in and
e-business novelty. Partial Least Squares Structured Equation Modelling (PLS-SEM)
was used to assess a randomly chosen sample of 120 digital entrepreneurs in Western
Province, Sri Lanka. It was discovered that there is a strong correlation between e-business performance and competency in digital business strategy, IT business process integration, and both. These variables explained 34% of the variation of the e-business success. The report makes some recommendations for steps that entrepreneurs and the government should take to succeed in digital commerce in light of its results
CEO duality, tenure, and compensation: is there a link? - an evidence from the Indian market
Get PDFPurpose: This study examines the relationship between CEOs playing a dual
administrative role in a company and their tenure and compensation. This paper
examines the research problem by applying four theoretical frameworks—
“managerial power theory,” “efficient contracting theory,” “ability matching
theory,” and “bargaining theory.”
Design/methodology/approach: The research sample includes 1,223 companies
across 50 industries, totaling 4,419 firm years from the year 2011 to 2021. The
findings are more robust when industry-fixed effects are modeled into the
relationship. A variable, like the persistence of ROA, is also introduced into the
model.
Findings: Despite some heterogeneity in the effects of CEO duality and CEO
tenure, the results reveal a favorable influence of CEO duality and CEO tenure,
suggesting that bargaining theory holds good concerning CEO remuneration in
Indian companies. CEOs who can keep a high persistent ROA may see an
increase in their remuneration.
Implications: Because there is a positive association between the size of the
company and the compensation the CEO receives, it comes to reason that larger
organizations are leveraging pay to lure the best suitable candidates. It would
appear that growing Indian firms are prepared to pay more for CEOs with the
experience and competence to take their company to new heights. This is a direct
result of the positive implications that MBV has. Due to the favorable impact of
ROA IOP, CEOs who maintain a high return on assets over time might anticipate
receiving a larger compensation package.
Originality Value: It is the first study to use a large sample of 50 industries from
the Indian market providing data on CEO remuneration and other characteristics,
and also the first study to test the impact of volatile ROA on CEO remuneration
Efficiency enhancement in solvent free dye-sensitized solar cells by incorporation of PbS quantum dots
Get PDFInexpensive dye-sensitized solar cells (DSSCs) show promise as a viable third-generation solar
cell technology. Usually, Ru-based dye molecules are used in DSSCs. A particular dye
molecule can only absorb the light photon from a particular wavelength range. The
enhancement of Dye-Sensitized Solar Cell (DSSC) performance can be achieved through cosensitization with additional dyes or quantum dots (QDs). Quantum dots, owing to their
diminutive dimensions and quantum confinement phenomena, which are modifiable by altering
their size and morphology, manifest distinct electronic and optical characteristics that are
particularly pertinent to the optimization of DSSCs. In this study, TiO2 – based PbS/N719 dye
co-sensitized quasi–solid solar cells have been fabricated and characterized. DSSCs comprised
with dye and the PbS QDs showed an efficiency of 4.72% with a higher short-circuit current
density of 2.30 mA cm-2 whereas the DSSC fabricated with only Ru N719 dye delivered 4.12%
efficiency under the same light condition with 100 mW cm-2
. The solar cell sensitized solely
with N719 dye demonstrates an efficiency of 4.12%. Around 14% enhancement in the
efficiency of DSSCs has been achieved due to the incorporation of PbS QDs
Diversity of macro-invertebrates in Thondamanaru lagoon
Get PDFMacro-invertebrates are considered as effective bio indicator of the
aquatic ecosystem. Aim of this study is to documenting the diversity and abundance
of macro-invertebrates of Thondamanaru lagoon. Sampling was done fortnightly basis
from November 2021 to October 2022 from selected 3 sampling sites in
Thondamanaru lagoon (S1- beyond the barrage, in front of Field Work Center; S2-
near to the barrage and front of Selva Sannathi Kovil and S3- near to sand bar).
Samples were collected from each site by using hand net and scoop. A total of 1222
individuals from 7 arthropod families and 15 mollusc families were identified. Based on
their morphological characters, 31 taxa were identified by using standard keys. Among
all recorded taxa, Gastropods Cerithidea cingulata (24% - 38%) and Clithon oulalensis
(31% - 46%) were the most abundant in all the selected sites in Thondamanaru lagoon
from family Potamididae and Neritidae, respectively. Macrobrachium sp. (site S1),
Penaeus indicus and Penaeus monodon (site S2) were least abundant (1 %).
Occurrence of identified taxa at site S3, Libinia emarginata, Oratosquilla oratoria,
Murex trapa, Cernuella virgata and Olivancillaria gibbosa were recorded as the least
abundant species (≤ 1% ). Species richness and Simpson Index were showed
significant difference (p <0.05) among three sites. According to the Shannon Weiner
(H) and Simpson (D) Indices, the highest species diversity was observed in Site 3 (H1.9018, D- 0.2072) followed by Site 2 (H- 1.1434, D- 0.3683) and Site 1 (H-1.3995, D0.2805). The highest abundance of macro-invertebrates was recorded in Site 2 (478)
followed by Site 3(466) and Site 1 (278). These results revealed that barrage
construction across the Thondamanaru lagoon impact on macro-invertebrate diversity.
It is very helpful for the conservation of biodiversity of this lagoon