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Simultaneous biodegradation of harmful Cylindrospermopsis raciborskii and cylindrospermopsin toxin in batch culture by single Bacillus strain

Research Abstract

This study investigates the capability of a Bacillus flexus strain isolated from decayed cyanobacterial blooms for the bioremediation of Cylindrospermopsis raciborskii and cylindrospermopsin (CYN) toxin. The algicidal activity of this strain was tested by co-cultivation with C. raciborskii cultures. CYN biodegradation was investigated in the presence of living and heat-inactivated bacterial cells or bacterial filtrate. Living bacterial cells inhibited C. raciborskii growth after 2 days of incubation with complete cell death at day 5. Bacterial filtrate caused a rapid reduction in C. raciborskii growth at the first day, with complete cell lysis at day 3. Only living cells of SSZ01 caused reduction in CYN released into the medium during the bacterial decay of C. raciborskii cells. The biodegradation rate of CYN by SSZ01 relied on initial toxin concentrations. The highest rate (42 μg CYN L−1 day−1 ) was obtained at the higher initial concentration (300 μg L−1 ), and the lowest (4μg CYN L−1 day−1 ) was at lower concentration (50 μg L−1 ). These results suggest that this bacterial strain could be employed to bioremediate cyanobacterial blooms in freshwaters. Also, the application of this bacterium in slow sand filters would give possibilities for degradation and bioremediation of cyanotoxins in drinking water treatment plants.

Research Authors
Zakaria Mohamed1 & Saad Alamri2 & Mohamed Hashem
Research Date
Research Journal
Environmental Science and Pollution Research
Research Pages
pages5153–5161
Research Publisher
springer
Research Vol
29
Research Website
https://link.springer.com/article/10.1007/s11356-021-16062-z
Research Year
2022

Secondary invader bacteria associated with the red pest weevil infestation in date palm trees

Research Abstract

The worldwide loss of date palm (Phoenix dactylifera L.) productivity is due to the
infestation of the red pest weevil (RPW). The pest makes tunnels in the tree trunk
and could be followed by secondary microbial infections causing oozing of fluid
with a distinct fermentation odor. This study aimed at isolation and identification
of secondary invader bacteria associated with the RPW and confirmation of their
potential destructive effect on the tree. Four bacterial isolates were recovered from
the infested date palm tissues, and they were identified based on phenotypic characteristics
using the VITEK2 system. Three out of the four isolates were identified as
Pseudomonas aeruginosa, and one isolate was identified as Burkholderia cepacia.
All isolates caused rot of date palm germinated seeds (up to 40%), and wilt and root
rot of date palm seedlings (40–100%). Pseudomonas aeruginosa (isolate No. 3) was
the most aggressive isolate that involved 40% mortality and caused 100% of root rot
incidence in date palm seedlings. Burkholderia cepacia showed the lowest degree of
rot on the germinated seeds, percentage mortality, percentage root rot incidence of
date palm seedlings. Pseudomonas aeruginosa (isolate No. 1) and B. cepacia caused
a high loss in the weight of date palm petioles tissues (about 10%). The study threw
light on the detrimental effects of secondary invader microbes associated with the
RPW infestation. The study recommended an application of an integrated management
program containing both antibacterial and insecticidal preparation in the management
of the RPW to avoid a further negative effect on the palm trees

Research Authors
El-Sayed H. E. Ziedan1 Saad A. Alamri2 Mohamed Hashem2,3 Yasser S. Mostafa2
Research Date
Research Journal
ِAgronomy journal
Research Pages
4271-4279
Research Publisher
Wiley
Research Vol
113(5)
Research Website
https://acsess.onlinelibrary.wiley.com/doi/epdf/10.1002/agj2.20800
Research Year
2021

Profitable exploitation of biodegradable polymer including chitosan blended potato peels’ starch waste as an alternative source of petroleum plastics

Research Abstract

Humans are extensively using synthetic plastic products for multiple life purposes. Non-degradability of these products affected
the nature and extremely harms the environment. Herein, biodegradable membranes with different ratios of chitosan/starch
waste have been prepared. These membranes have been submitted for in vitro enzymatic biodegradation followed by examination
by SEM, FTIR, Raman scattering spectral analyses, surface roughness measurement, degree of swelling, and contact
angle. The obtained membranes showed biodegradability significant features which increased by increasing starch ratio and
has been confirmed by the formation of holes that were demonstrated by SEM micrographs. Both of surface roughness and
water uptake values of the prepared membranes have been increased in all prepared membranes after the enzymatic treatment
to the maximum measured value of 0.87 μm and 200%, respectively. However, water contact angle values of the prepared
membranes have been decreased after the enzymatic treatment to reach 25 θ as the lowest measured value. These results suggest
the application of chitosan-blended starch membranes as alternatives for petroleum plastics with more environmental safety.

Research Authors
Tarek H. Taha1 · M. A. Abu‑Saied2 · Mohamed Elnouby3 · Mohamed Hashem4,5 · Saad Alamri4,6 · E. A. El Desouky7 · Kareem Morsy4,8
Research Date
Research Journal
Biomass Conversion and Biorefinery
Research Publisher
Springer
Research Website
https://link.springer.com/article/10.1007/s13399-021-02244-9
Research Year
2022

Prediction Models Founded on Soil Characteristics for the Estimated Uptake of Nine Metals by Okra Plant, Abelmoschus esculentus (L.) Moench., Cultivated in Agricultural Soils Modified with Varying Sewage Sludge Concentrations

Research Abstract

Prediction models were developed to estimate the extent to which the metals Cd, Co,
Cr, Cu, Fe, Mn, Ni, Pb, and Zn were taken up by the fruits, the leaves, the stems, and the roots
of the okra plant, Abelmoschus esculentus (L.) Moench., grown under greenhouse conditions in soil
modified with a spectrum of sewage sludge concentrations: 0, 10, 20, 30, 40, and 50 g/kg. All the
metals under investigation, apart from Cd, were more concentrated in the A. esculentus roots than
in any other organ. Overall, the sum of the metal concentration (mg/kg) within the varying plant
tissues can be ranked in the following order: roots (13,795.5) > leaves (1252.7) > fruits (489.3) > stems
(469.6). For five of the metals (i.e., Cd, Co, Fe, Mn, and Pb), the BCF was <1; for the remaining four
metals, the BCF was >1, (i.e., Cr, 1.074; Cu, 1.347; Ni, 1.576; and Zn, 1.031). The metal BCFs were
negatively correlated with the pH of the soil and positively correlated with soil OM content. The
above-ground tissues exhibited a TF < 1 for all metals, apart from Cd with respect to the leaves (2.003)
and the fruits (2.489), and with the exception of Mn in relation to the leaves (1.149). Further positive
associations were demonstrated for the concentrations of all the metals in each examined plant
tissue and the corresponding soil metal concentration. The tissue uptakes of the nine metals were
negatively correlated with soil pH, but positively associated with the OM content in the soil. The
generated models showed high performance accuracy; students’ t-tests indicated that any differences
between the measured and forecasted concentrations of the nine metals within the four tissue types
of A. esculentus failed to reach significance. It can, therefore, be surmised that the prediction models
described in the current research form a feasible method with which to determine the safety and risk
to human health when cultivating the tested species in soils modified with sewage sludge.

Research Authors
Ebrahem M. Eid 1,2,* , Kamal H. Shaltout 3, Saad A. M. Alamri 1, Sulaiman A. Alrumman 1 , Nasser Sewelam 3, Mostafa A. Taher 1,4, Mohamed Hashem 1,5, Yasser S. Mostafa 1 and Mohamed T. Ahmed
Research Date
Research Journal
Sustainability
Research Pages
12356
Research Publisher
MDPI
Research Vol
13(22)
Research Website
https://www.mdpi.com/2071-1050/13/22/12356
Research Year
2021

Planned Application of Sewage Sludge Recirculates Nutrients to Agricultural Soil and Improves Growth of Okra (Abelmoschus esculentus (L.) Moench) Plants

Research Abstract

The aim of this study was to investigate the feasibility of using sewage sludge (SS) biosolids
as a low‐cost soil fertilizer to improve soil characteristics and crop yields. Okra (Abelmoschus
esculentus (L.) Moench) plants were grown in soil supplemented with different concentrations of SS
(0, 10, 20, 30, 40, and 50 g/kg). The results showed that SS soil application led to improved soil
quality with a 93% increase of organic matter (at SS dose of 10 g/kg), decreased pH (a reduction
from 8.38 to 7.34), and enhanced macro‐ and micro‐ nutrient contents. The levels of all the investigated
heavy metals (HMs; Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in the postharvest SS‐amended
soil were within the prescribed safe limits. The application of SS to soil considerably enhanced the
growth parameters of okra plants. Total biomass increased 13‐fold and absolute growth rate increased
10‐fold compared to plants grown in nonamended (control) soils. Among the applied SS
doses, the 10 g/kg SS dose led to the highest values of the measured growth parameters, compared
to those of plants grown in control soils. The induced growth at 10 g/kg SS was accompanied by a
substantial increase in metal content in roots, stems, leaves, and fruits; however, all levels remained
within safe limits. Consequently, the data presented in this study suggest that SS could be used as
a sustainable organic fertilizer, also serving as an ecofriendly method of SS recycling.

Research Authors
Ebrahem M. Eid 1,2, Kamal H. Shaltout 3, Saad A. M. Alamri 1, Sulaiman A. Alrumman 1, Mostafa A. Taher 1,4, Ahmed F. El‐Bebany 5, Mohamed Hashem 1,6, Tarek M. Galal 7, Yasser S. Mostafa 1, Mohamed T. Ahmed 1, Nasser Sewelam 3,* and Afaf A. Nessem
Research Date
Research Journal
Sustainability
Research Pages
740
Research Publisher
MDPI
Research Vol
14(2)
Research Website
https://www.mdpi.com/2071-1050/14/2/740
Research Year
2022

PGPR-Mediated Plant Growth Attributes and Metal Extraction Ability of Sesbania sesban L. in Industrially Contaminated Soils

Research Abstract

The release of harmful wastes via different industrial activities is the main cause of heavy
metal toxicity. The present study was conducted to assess the effects of heavy metal stress on the
plant growth traits, antioxidant enzyme activities, chlorophyll content and proline content of Sesbania
sesban with/without the inoculation of heavy-metal-tolerant Bacillus gibsonii and B. xiamenensis. Both
PGP strains showed prominent ACC-deaminase, indole acetic acid, exopolysaccharides production
and tolerance at different heavy metal concentrations (50–1000 mg/L). Further, in a pot experiment,
S. sesban seeds were grown in contaminated and noncontaminated soils. After harvesting, plants
were used for the further analysis of growth parameters. The experiment comprised of six different
treatments. The effects of heavy metal stress and bacterial inoculation on the plant root length;
shoot length; fresh and dry weight; photosynthetic pigments; proline content; antioxidant activity;
and absorption of metals were observed at the end of the experiment. The results revealed that
industrially contaminated soils distinctly reduced the growth of plants. However, both PGPR strains
enhanced the root length up to 105% and 80%. The shoot length was increased by 133% and 75%,
and the fresh weight was increased by 121% and 129%. The proline content and antioxidant enzymes
posed dual effects on the plants growing in industrially contaminated soil, allowing them to cope
with the metal stress, which enhanced the plant growth. The proline content was increased up to
190% and 179% by the inoculation of bacterial strains. Antioxidant enzymes, such as SOD, increased
to about 216% and 245%, while POD increased up to 48% and 49%, respectively. The results clearly
show that the utilized PGPR strains might be strong candidates to assist S. sesban growth under
heavy metal stress conditions. We highly suggest these PGPR strains for further implementation in
field experiments.

Research Authors
Nida Zainab 1, Amna 1, Amir Abdullah Khan 2 , Muhammad Atif Azeem 1, Baber Ali 1, Tongtong Wang 2 , Fuchen Shi 2,*, Suliman Mohammed Alghanem 3, Muhammad Farooq Hussain Munis 1 , Mohamed Hashem 4,5, Saad Alamri 4, Arafat Abdel Hamed Abdel Latef 6 , Omar M
Research Date
Research Journal
Agronomy
Research Pages
1820
Research Publisher
MDPI
Research Vol
11(9)
Research Website
https://www.mdpi.com/2073-4395/11/9/1820
Research Year
2021

Path analysis based on genetic association of yield components and insects pest in upland cotton varieties

Research Abstract

Gossypium hirsutum L. is also called upland cotton or Mexican cotton. It is the most widely
cultivated species of cotton in the whole world. Globally, about 90% of all cotton production
comes from the cultivars derived from this species. Some genetic parameters like monopodial
branches per plant, sympodial branches per plant, sympodial branch length, bolls per
plant, boll weight, sympo-boll distance, Ginning Out Turn%, staple length (rg = 0.9199**),
and fiber strength along with seed cotton yield were evaluated for their potential utilization
via selection in seed cotton yield improvement. Significant positive genetic correlations were
estimated for monopodial branches per plant (rg = 0.9722**), sympodial branches per plant
(rg = 0.7098**), sympodial branch length (rg = 0.617**), bolls per plant (rg = 0.8271**),
boll weight (rg = 0.8065**), sympo-boll distance (rg = 0.6507**), Ginning Out Turn (GOT)%
(rg = 0.7541**), staple length (rg = 0.9199**), and fiber strength (rg = 0.7534**) with seed
cotton yield. A path analysis of all the yield traits under study revealed strong positive direct
effects of monopodial branch length (1.1556), sympo-boll distance (0.8173) and staple
length (0.7633), while plant height exerted a highly strong direct negative effect (-1.2096) on
yield. It is concluded that a direct selection based on monopodial branch length and sympoboll
distance, and staple length is effective, whereas, monopodial branch length, and sympodial
branch length are good selection indicators via bolls per plant for yield improvement
in cotton.

Research Authors
Mussarat Shaheen1, Hafiz Abdul Rauf1, Muhammad Ahmed Taj2, Muhammad Yousaf Ali3*, Muhammad Amjad BashirID 4, Sagheer Atta4, Hasnain Farooq5,6, Reem A. Alajmi7, Mohamed Hashem8,9, Saad Alamri
Research Date
Research Journal
PLOS ONE
Research Publisher
PLOS ONE
Research Vol
16(12)
Research Website
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0260971
Research Year
2021

Management of Deleterious Effect of Fusarium oxysporum Associated with Red PalmWeevil Infestation of Date Palm Trees

Research Abstract

Red palm weevil (RPW) is a dangerous pest that infects the date palm tree and makes
tunnels in the tree’s trunk. RPW infection is followed by secondary invaders of microorganisms
that cause degradation of the trunk tissues leading to toppling the crown and death of the tree in a
short time. This study showed that Fusarium oxysporum Schlecht. was the common fungal species
isolated from the root and trunk tissues of the date trees infested with RPW, which recorded 100% of
frequency. Pathogenicity of 4 isolates of F. oxysporum was confirmed on date palm seeds and seedlings.
The results confirmed that all isolates involved in rot of the germinated seeds (40–100% incidence),
root rot, and death of palm seedlings (20–100%) under artificial infection as well as degradation of
date palm petioles. Application of 20 L/palm of systemic fungicide (Topsin) at 1% as foliar and soil
drench of date palm for successive three times successfully reduced development of the deterioration
and suppressed the growth of F. oxysporum. Interestingly this fungicide did not suppress the growth
of Trichoderma viride Pers. So, our results recommend this fungicide to suppress the pathological
and degradable activities of F. oxysporum during the integrated pest management of RPW on date
palm trees.

Research Authors
El-Sayed H. E. Ziedan 1, Mohamed Hashem 2,3,* , Yasser S. Mostafa 2 and Saad Alamri
Research Date
Research Journal
agriculture
Research Pages
71
Research Publisher
MDPI
Research Vol
12(1)
Research Website
https://www.mdpi.com/2077-0472/12/1/71
Research Year
2022

Inhibitory effects of the brown macroalga Turbinaria ornata on cyst germination and progeny cells of five harmful dinoflagellate species

Research Abstract

This study investigates the inhibitory effects of thalli and their extracts of the macroalga Turbinaria ornata on the germination of dinoflagellate cysts, previously isolated from Red Sea surface sediments. The experiments were conducted on cysts of five harmful dinoflagellate species including Alexandrium catenella, Cochlodinium polykrikos, Dinophysis accuminata, Prorocentrum cordatum and Scrippsiella trochoidea. The results showed neither macroalgal thalli nor their extracts had direct impact on the cyst germination of all species. Instead, these macroalgal materials remarkably affected the germling viability and culturability of progeny cells of these cysts. Dry macroalgal thalli exhibited stronger inhibitory effects on germling viability and cell culturability (IC50= 0.235–0.543, 0.385–1.43 mg mL−1, respectively) than fresh thalli (IC50=2.201–4.716, 2.17–7.18 mg mL−1, respectively). The macroalgal ethanol extract was approximately 2-5 times more effective (IC50 = 0.012–0.047 and 0.024–0.089 mg mL−1, respectively) than aqueous extract (IC50 = 0.04–0.1 and 0.054–0.207 mg mL−1, respectively) against the germling viability and vegetative progeny cells of all cyst species. Among different species, A. catenella and C. polykrikos germlings were more sensitive to macroalgal thalli and their extracts than those of S. trochoidea, P. cordatum and D. acuminata. Meanwhile, progeny cells of A. catenella exhibited the highest sensitivity to all macroalgal materials. Our results suggest that the use of T. ornata may be a promising strategy for inhibiting the division of progeny cells of dinoflagellate cysts and impairing the recurrence of HABs in confined coastal areas.

Research Authors
ZakariaMohamedaSaadAlamribMohamedHashem
Research Date
Research Pages
63-74
Research Publisher
Elsevier
Research Vol
64(1)
Research Website
https://www.sciencedirect.com/science/article/pii/S0078323421000828?via%3Dihub
Research Year
2022

Impact of multiple environmental factors on species abundance in various forest layers using an integrative modeling approach

Research Abstract

It was hypothesized that multiple environmental factors influence distribution and abundance of
plant species in different vegetation layers of the forest ecosystem=. Here, we have assessed plant
diversity, abundance and its relationship with multiple factors through an integrative modeling
approach. To substantiate or negate our hypothesis, Quadrat quantitative ecological methods
were carried out for the sampling of vegetation in Humid Forest Ecosystem of the Western
Himalayas. Rectangular plots of 100 m, 50 m and 1 m were established for trees, shrubs and herb
species, respectively. All the edaphic, topographic, climatic and disturbance factors were determined
using different standard procedures and protocols. We have applied multiple linear
regression and structural equation models using R-Software on most abundant plant species each
from trees, shrubs and herbs. Preliminary, integrative modeling showed that the species abundance
is significantly associated with a set of soil nutrients (physio-chemical variables), topography
(aspect, slope, elevation) and disturbance factors (anthropogenic and grazing pressure).
The species dominance effects were synchronously influenced (p˂0.025) by the soil physical
characters (sand, silt and clay), canopy and regeneration potentials compared to other factors.
Our results provide bases to understand the underlying mechanisms of species abundance and its
importance of the forest ecosystem in the western Himalayas. This work concludes that ecological
diversity is overall the result of multiple factors but climatic, topographic, anthropogenic and
grazing pressures primarily shape the diversity and functioning in a forest ecosystem. Additionally,
we found a clear pattern that variations in edaphic factors cause the abundance of certain
species over others.

Research Authors
Amjad ur Rahman a,b,c, Shujaul Mulk Khan a,*, Zeeshan Ahmad a, Saad Alamri d, Mohamed Hashem d,e, Muhammad Ilyas b, Ahmet Aksoy f, Canan Dülgero˘glu f, Gulzar Khan, Shahab Ali
Research Date
Research Journal
Global Ecology and Conservation
Research Pages
e01712
Research Publisher
Elsevier
Research Vol
29
Research Website
https://www.sciencedirect.com/science/article/pii/S2351989421002626?via%3Dihub
Research Year
2021
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