Metformin (1, 1-dimethylbiguanide) as Potential Organic Base Catalyst for the Transesterification of Coconut Oil with Methanol

Metformin (1, 1-dimethylbiguanide) as Potential Organic Base Catalyst for the Transesterification of Coconut Oil with Methanol

Anonymous

by: Juvinch R. Vicente, Ida G. Pahila, Mae Grace G. Nillos

Abstract

Biodiesel is conventionally produced by alkali-based transesterification, which is limited by the presence of water and the free fatty acid content of oil feedstock. This study investigated the potential of metformin (1,1-dimethylbiguanide) as an alternative organic base catalyst for the transesterification of coconut oil with methanol. Two parameters were considered in this work, the catalyst loading and the amount of water in the feedstock. When no water is present in the feedstock, metformin showed a significant FAME yield of 55 ± 8% at 1.0% w/w catalyst/oil. Increasing the amount of metformin to 2.0% w/w significantly increased FAME yield to 71 ± 4%. In the presence of water (5.0%, w/w water/oil) however, the catalytic performance of metformin was practically lost, with FAME yields of only 5.5 ± 0.3% (1.0% w/w catalyst/oil) and 2.6 ± 0.4% (2.0% w/w catalyst/ oil). Overall, metformin showed the ability as a catalyst for the transesterification of coconut oil with methanol. However, its efficiency is limited only to conditions where the water level in the feedstock is minimal.

Keywords: Fatty acid methyl ester (FAME); fatty acid; biodiesel; plant-based oils

An Iterative Model-Free Approach in Detecting System-wise Outliers as Applied to Regional Fisheries Production in the Philippines from 2005 to 2022

An Iterative Model-Free Approach in Detecting System-wise Outliers as Applied to Regional Fisheries Production in the Philippines from 2005 to 2022

Anonymous

by: Daniel David M. Pamplona

Abstract

A flexible method for detecting system-wise outliers is presented. This approach attempts to simplify the detection of anomalous observations without relying on large datasets and complicated statistical modeling techniques. The method utilizes the leave-one-out method, similar to cross-validation technique in data resampling. Using this approach, observations are iteratively removed and a measure of variability is recalculated in each iteration. By doing so, the influence of each observation is evaluated in the data. Results of the simulation study show that this new method adequately recognizes anomalies in several data scenarios while minimizing incorrect detections. The method worked particularly well in data scenarios with high number of time points and low to moderate variability. On the contrary, the method showed weak performance when applied to datasets with low number of time points and very high variability. The proposed method was also applied to detect irregularities in regional fisheries production in the Philippines. Upon visual validation, results show that the new method was able to detect irregularities in the production data, such as trend and extreme shocks.

Keywords:System-wise, Outlier Detection, Anomaly Detection, Multiple Time Series, Monte Carlo Simulation,
Fisheries Production

Cephalopod Fishery of the Northern Sulu Sea, Philippines

Cephalopod Fishery of the Northern Sulu Sea, Philippines

Anonymous

by: Annabelle GC del Norte-Campos, Wilfredo L. Campos

Abstract

The cephalopod fisheries of the northern Sulu Sea based on Malalison Island, Culasi and in Tibiao, Antique, Philippines were monitored over a period of two years from April 2018 to March 2020, where catch (kg), species caught by gear, and fishing effort, were recorded daily in situ from a fixed and representative number of fishers. From these, catch, corresponding value, and fisher income were estimated. Of the three gears, the jigger fully (100%) targets cephalopods, while spearfishing catch fish slightly more than cephalopods. A total of five cephalopod species are exploited by the fishery i.e., two squids (Sepioteuthis lessoniana & Sthenotheuthis oualaniensis), one cuttlefish (Sepia latimanus), and two species of octopods (Callistoctopus nocturnus, and Octopus cyanea). Of these, the octopod species dominated the catch (71%) with S. lessoniana comprising the least (2%). Hook and line showed the highest catch (41.98%) of all gears, responsible for catching the two octopod species the most. Annual fisher income proved to be highest (annual mean PhP 54,508.84 yr-1) among those employing jiggers to exploit S. oualaniensis, the most expensive (PhP200 kg-1) species. The fishers’ annual income may not be much, but is augmented by other forms of fishing, specifically gleaning. Studies on these species’ population biology (age, growth, and mortality) and reproductive biology are necessary to further elucidate the level of exploitation towards ensuring their sustainable utilization.

Keywords: Cephalopod fisheries, Northern Sulu Sea, species population biology

Community characteristics of mangrove species in Guimaras after an oil spill

Community characteristics of mangrove species in Guimaras after an oil spill

Anonymous

by: Resurreccion B. Sabada*, Abner P. Barnuevo, Christy Madas, Joseph Biñas, and Edgar Hortillosa

Abstract

The oil spill from M/T Solar I on August 11,2006 off southern Guimaras, Philippines released over two million liters of Bunker C industrial fuel. Visibly affected were the highly vulnerable mangroves. Spilled oil were stranded and settled in the shores affecting mangrove trees, saplings, and wildings; and including the associated resident fauna. The effect of oil spill in mangrove can be acute, secondary, and chronic and this paper focused only the acute effects of oil on the the affected mangrove flora in the affected sites in Guimaras. Specifically, the study (a) identified true mangrove species affected; (b) described the community structure; and (c) mapped the degree of oiling and areas with defoliated mangroves. The assessment was conducted on August 19 to November 18, 2006 for community structure analysis in 14 oiled sites, namely; Brgys. Dolores, Tando, Lucmayan, San Roque, La Paz (Taklong Island National Marine Reserve), Cabalagnan, Igdarapdap in Nueva Valencia; Brgys. Algeria, Sabang, Sebaste, San Isidro, Bubog in Sibunag; Igcawayan and Sebario in San Lorenzo. Two unoiled mangroves (reference sites) were also surveyed in Brgys. Getulio, Buenavista; and Lawi, Jordan. In terms of floristic composition, areas included in this assessment had 29 true mangrove species representing 14 families, or about 83% of the total number of know Philippines mangrove species. The highest floristic composition was record in Taklong Island National Marine Reserve (TINMR), in La Paz with 26 species. The most frequently occurring species were Avicennia marina, Rhizophora apiculate, R. mucronata, R. stylosa, and Sonneratia alba which occurred in 15 sites (93.8%) and they were also the dominating species with 66.66, 52.02, 27.48, 30.72, and 50.01 relative dominance respectively. Large-sized trees were found in Sebario, Igdarapdap, and Bubog with 13.31, 12.51, and 10.55 cm diameter at breast height respectively. Stand basal area ranged from 1.96 m2 ha-1 in Sebaste, to 56.36 m2 ha-1 in Bubog. The presence of large-sized S. alba in Bubog contributed greatly to its stand in basal area while relatively young or generating mangroves composed the stand of the latter. Densities per plant category vary widely per site. Wilding density was highest in Dolores with 49,567 individual ha-1 and lowest in Tando with 700 individual ha-1 ; sapling density was highest in Dolores with 2900 individual ha-1 and lowest in San Isidro with 659 individuals ha-1 ; and tree density was highest in TINMR with 3,983 individual ha-1 and lowest in Sabang with 783 individual ha-1 . Species diversity was highest in Sebaste (H’ = 1.088) and lowest in Dolores (H’ = 0.497). This high diversity is mainly attributed by the absence of the dominant species. The acute effects during the three month assessment involved the massive death of mangroves in Lucmayan, Bagatnan and Alman Sur which accounted to 0.932 ha. However, the remaining stranded oil in the mangrove area will continue to be a source of stress that cause chronic effects that are observed in a continuous and regular monitoring of the areas affected.

Keywords:Mangroves, mangrove community structure, Guimaras, oil spill

Assessment of the short-term structural damage in the Guimaras mangroves by the M/T Solar I Oil Spill

Assessment of the short-term structural damage in the Guimaras mangroves by the M/T Solar I Oil spill

Anonymous

by: Resurreccion B. Sabada*, Abner P. Barnuevo, Christy S. Madas, Joseph Biñas, and Edgar Hortillosa

Abstract

Mangrove forests of Guimaras were affected by M/T Solar oil spill on August 11,2006 releasing more than two million liters of Bunker C industrial fuel. Acute and lethal damage to these mangroves was assessed in the field and from aerial photographs. The study (a) measured the heights and extent of oil bands on trees, saplings, and wildings; (b) determined the percentages of oiling and mortality by plant category; and (c) determined the percentages mortality by species. Field assessment was conducted on August 19 to November 18, 2006 in 14 oiled and two unoiled sites. Mangroves surveyed in Nueva Valencia were all coated with oil except Dolores and Igdarapdap where only traces of oil were observed. The sites in Sibunag and San Lorenzo had only traces of oil painted on trunks, roots or leaves. Oil levels among trees ranged from 0.1-1.2 m in height (13.43% of the tree height coated with oil) and highest in Tandog Island and Lucmayan in Nueva Valencia. The same degree of oiling among saplings and wildings were observed among sites except that a patch of reforested area in Alegria, Sibunag was heavily coated that reached up to 0.4 m for saplings and 0.3 m for wildings. The sites within La Paz had the highest percentage of oiled trees (74.4%) and saplings (72.9%), while Cabalagnan had the highest percentage of oiled wildings (65.5%). Total area of dead mangroves accounted to only 0.932 ha distributed in Sitio Bgatnan, Lapaz (0.490 ha), Sitio Tuguisan, Lapaz (0.008 ha), and Panobolon (0.389 ha) all in Nueva Valencia. Areas with massive death of mangrove particularly trees were primarily characterized by a low hydrodynamic, tidal flushing is minimal thus leading to a delay in oil removal by natural processes. In Tandog Island, defoliated mangrove saplings and wildings were also observed, albeit very few in number and occurred sporadically. Overall species mortality was only 0.97%. Saplings had the highest with 1.60%, trees had 1.44%, and wildings had 0.47%. This low mortality among wildings is attributed by their viviparous nature that allowed them to survive in oiled sediments up to the point where food reserves stored in propagules were exhausted, where upon the plants died. Within sites, Lucmayan had 12.88% tree mortality, while Sitios Bagatnan and Tuguisan both in La Paz had 11.11% and 4.96% respectively. Saplings’ high mortality was observed in Sitio Bagatnan with 8.20%, while that of wildings was in Tandog Island  with 7.41%. Among the 29 species affected, only five species showed mortality: Avicennia marina (0.03%), Phizophora apiculate (0.16%), R. mucronata (0.26%), R. stylosa (0.48%), and Sonnerratia alba (0.04). Massive death were concentrated only in the inner part of the forest stretching towards the terrestrial margin while the outer fringe remained intact and often had one or two surviving trees along the seaward margin.

Keywords:mangroves, Guimaras, oil spill, mangrove mortality

Initial assessment of fungal population at various sites in Guimaras after the Solar I Oil Spill

Initial assessment of fungal population at various sites in Guimaras after the Solar I Oil Spill

Anonymous

by: *Resurreccion B. Sadaba, Erl Flores and Andrea Panilla

Abstract

Many tropical environments areas are being heavily disturbed by human activity such as the marine environment. They have been a subject to contamination by organic pollutants from a variety of sources including accidental oil spills. On August 11,2006, M/T Solar I chartered by Petron sunk off the coast of Southern Guimaras released more than two million liters of Bunker C oil into the sea and affected diverse coastal habitats and ecosystems with considerable environmental damage. There is a little information on the effect of disturbance on fungi in tropical coastal ecosystems such as sandy beaches and mangroves which are habitats distinctive to the tropics. This study, therefore, examined the effects of the oil spill on the fungal diversity and density among the contaminated sites in the southern part of the island of Guimaras, Philippines within two months after the spill. The initial assessment was conducted on October 11, 2006 at eight sites were selected composed of six oil-contaminated sites and two from in-contaminated areas that served as control. Samples obtained were composed of one beach water sample and three soil samples. Yeasts and filamentous fungi were examined by macroscopic and microscopic observation of colonies. Identification was based on available keys and monographs. Majority of species isolated were mitosporic and typical soil fungi which are terrestrial in origin but are considered as facultative marine fungi. There are more fungal isolates at oil-contaminated sites than un-contaminated sites at 23 and 13 species, respectively as well as a higher Shannon Index of Diversity (H`) at 1.248 and 1.039, respectively. Among the filamentous fungi, nine genera were represented by Aspergillus, Aureobasidium, Cladosporium, Memnoniella, Monilia, Mucor, Penicillium, Pestalotia and Sporothrix. There was allow index of similarity of species composition between oil-contaminated and un-contaminated sites as shown by Jaccard’s coefficient of similarity (J = 0.40) and Sorensen coefficient of similarity: C = 0.57. All samples from oil-contaminated sites yielded a higher diversity and evenness of fungi compared with un-contaminated sites based on the Index of Diversity consistent with the overall trend of fungal occurrences. It appears that most of the oil-contaminated sites particularly beach and mangrove surface soil samples at Taklong Island exhibited a much higher fungal load compared with the un-contaminated sites that could possibly be attributed to the presence of oil in areas that favored their growth. This study provided some evidences on the short-term impacts in terms of change in fungal assemblages and density. Although the report is not conclusive considering the absence of pre-spill data and variability between months or year, the evidence indicates that there was disturbance brought about by the oil. Thus, the need for a long-term monitoring program to examine the effects of oil in these areas to determine recovery and re-instatement of normal fungal flora.

Keywords:Oil spill, marine fungi, bioremediation

Seagrass meadows in Southern Guimaras: Immediate Post-Oil Spill Status

Seagrass meadows in Southern Guimaras: Immediate Post-Oil Spill Status

Anonymous

by: *Maria Frances J. Nievales

Abstract

The M/V Solar 1 Oil Spill damaged the ecology of southern Guimaras. Bunker fuel floated meters from shore for weeks hovering over critical ecological habitats including seagrass meadows. This study looked at the ecological status of seagrass meadows in the southern section of Guimaras Island immediately after the oil spill event;  and, attempted to track temporal changes in monitoring stations exposed to varying degree of oiling to clarify potential short term responses of seagrasses. Nine (9) species in 6 genera of seagrasses were encountered in various meadows which included Thalassia hemprichii, Enhalus acoroides, Halophila ovalis, H, minor, Cymodocea rotundata, C. serrulata, Halodule uninervis, H. pinifolia and Syringodium isoetifolium. Majority of the meadows were mixed species assemblage with T. hemprichii generally as the dominant species. Poor seagrass cover (<5%) and sparse shoot density (<50 shoots/sqm) characterized monospecific beds dominated by E. acoroides along the channel (UP Channel) or protected muddy embayments (e.g. Alman, Panobolon Is. lee, Sabang). More open meadows are species-rich with good cover (> 60%) (e.g. Panobolon Is. Front, Natunga Island). Shoots were densest (>3000 shoots/ sqm) in monospecific Halodule beds near estuaries (e.g. Igang, Alegria) with likely broadly fluctuating salinities. The meadow adjacent to the oiled shoreline with minimal clean up (i.e. CALAPARAN) had the least seagrass cover (17.4+ 1.4), shoot and blade densities (293+ 94, 948+ 203) and dry above-ground biomass (34.0+ 15.5) compared to less impacted meadows or the Reference Site between December 2006 to March 2007. In CALAPARAN, seagrass cover and shoot density were lower 2 to 7 months after the oil spill event compared to its 2 weeks post oil spill or year ago levels. Seagrass stations within TINMR in November 2006, showed disturbingly high proportion of dying seagrass blades relative to the Reference Site or to more hydrodynamically open, impacted sites distant from the point source of the oil spill. These were clear suggestions of stress in oil-impacted seagrass meadows but must be distinguished from natural temporal fluctuations though longer-term monitoring.

Keywords: Seagrass, oil spill, Guimaras

An assessment of the impact of the Solar I Oil Spill on ichthyoplankton abundance, composition, and distribution in Southern Guimaras, Central Philippines

An assessment of the impact of the Solar I Oil Spill on ichthyoplankton abundance, composition, and distribution in Southern Guimaras, Central Philippines

Anonymous

by: Wilfredo L. Campos* and August S. Santillan

Abstract

The potential impact of the Solar I Oil Spill on the ichthyoplankton in southern Guimaras was investigated. Plankton samples were collected by means of 5 min surface horizontal tows using a 0.25 x 0.75m rectangular plankton net fitted with a bag of 300 mm mesh. At least 12 stations were sampled on each of 3 occasions corresponding to 2 weeks, 3 weeks, and 7 weeks after the spill. The results covering this period showed that fish egg and larval densities were no different from densities observed in the reserve in 2000 and 2001. The relative age distribution of the larvae showed the absence of flexion to late stages 2 weeks after the spill, indicating high egg and early larval mortality during this period. The major larval species groups observed in this study were the same dominant groups observed in previous surveys, except for the absence of nemipterids up to at least 3 weeks after the spill. In previous surveys, nemipterids made up about 11% of all larvae. Their absence immediately after the spill may likely affect subsequent recruitment in the area.

Keywords: Oil Spill; ichthyoplankton; Central Philippines

Initial assessment of the bacterial population of Guimaras waters and soil after the Solar I Oil Spill

Initial assessment of the bacterial population of Guimaras waters and soil after the Solar I Oil Spill

Anonymous

by: Christopher Sombito, Gilda Lio-Po, resurrecio Sadaba and Romelie Torreta

Abstract

A massive oil spill occurred near the shores of Guimaras Island, Philippines, in 11 Aug 2006 caused by the sunken MT Solar I vessel. The oil spill spread to neighboring towns of Guimaras damaging the marine coastal environment, consequently, causing health and economic problems, particularly, by affecting local fisheries, wildlife, and tourism. Hence, this study was conducted to assess, quantify, and isolate indigenous bacteria with potential petroleum hydrocarbon-degrading properties that could be used for bioremediation of oil spill contaminated areas in Guimaras and nearby provinces. Sampling were conducted in Oct and Nov 2006 to assess the level of both heterotrophic and hydrocarbon-degrading bacteria (HDB) from areas affected ( Tando, Taklong, Cabalagnan, Panobolon, Alegria, Sabang , Inampulugan) and unaffected (Lawi and Getulio) by the oil spill. Samples consisted of beach water and beach sand, mangrove surface soil and subsurface soil where levels of heterotrophic bacteria consisted of Total Aerobic Counts (TBC). Presumptive Vibrio Counts (PVC), Presumptive Aeromonas Counts (PAC) and Presumptive Pseudomonas counts (PPC) were determined. Likewise, the levels of hydrocarbon-degrading bacteria were also assessed. Results showed that heterotrophic bacteria were found in variable densities among the sampled sites with Nov soil and water samples, yielding higher counts than in Oct. The Significantly sample high density of total culturable bacteria yielded mean counts of 6.4 x 10 5 cfu/g from Taklong beach soil , 5.1 x 105 cfu/g from Alegria mangrove surface soil and 5.6 x 105 cfu/g from mangrove subsurface soil samples of Inampulugan in Nov 2006. The levels of Vibrio were highest in Getulio at 3.3 x 104 cfu/g and 2.4×104 cfu/g for beach and mangrove surface soil, respectively and in Sabang for mangrove sub-surface soil at 1.6 x104 cfu/g. The levels of Aeromonas were significantly highest in Alegria at 2.1 x 105 cfu/g for beach soil and in Getulio at 1.5 x105 cfu/g and 1.4 x 105 cfu/g for mangrove surface and sub-surface soil, respectively. The levels of Pseudomonas were significantly highest in Sabang for Mangrove surface soil at 2.3 x 104 cfu/g and in Cabalagnan at 1.4 x 105 cfu/g and 4.5 x 104 cfu/g for beach and mangrove sub-surface soil, respectively. Oil-degrading bacteria were also found in variable densities among the sampled sites including one of the oil spill unaffected sites but of low level. Although, some sites have relatively low levels and even some sites had undetectable level (<2.3 MPN/g or ml), Taklong beach soil yielded a significantly high level of hydrocarbon-degrading bacteria at 620 MPN/g. Thus, this study confirms the presence of petroleum hydrocarbon-degrading bacteria in some affected areas in Guimaras.

Keywords: oil spill, bacteria bioremediation, hydrocarbon-degrading bacteria, Philippines

Sediment and water contamination caused by the M/T Solar I Oil Spill in Southern Guimaras, Central Philippines

Sediment and water contamination caused by the M/T Solar I Oil Spill in Southern Guimaras, Central Philippines

Anonymous

by: Ida G. Pahila*, Hilario S. Taberna Jr, Leandro G. Gamarcha, Jay O. Martizano and Sharon Rose B. de la Rama

Abstract

About one month after the M/T Solar I oil spill in Southern Guimaras, surface sediment and water samples were collected to assess the extent of petroleum contamination. Among the contaminated shoreline and mangrove areas, Guiwanon and Taklong shore and Dungkaan mangrove have the highest level of Hexane Extractable Materials (HEM) and Polycyclic Aromatic Hydrocarbon (PAH) compounds relative to the unpolluted sediment sample from Igang, Guimaras and Tubbataha, Palawan. The extent of oil contamination in the intertidal zone of Taklong shore at low tide was 18 meters landward from the water and the highest level of HEM and PAH were observed in samples collected at the interface of the warer and the shore. However, BTEX (benzene, toluene, ethylbenzene and meta, ortho, para xylenes) in water and sediment samples collected 1 month after the oil spill are below minimum risk level, MRL (2ppm). This observation could be attributed to the higher rate of volatilization of most monoaromatic hydrocarbon (BTEX) with low flash points.

Keywords: PAH, BTEX,HEM