Musa Paradisiaca Research Articles

The Dynamics of Crop-Raiding Activity of African Elephant (Loxodonta cyclotis) at the Periphery of Mount Cameroon National Park, Southwest Region, Cameroon

Human-elephant conflict is common on cropland due to human encroachment into wildlife habitat, a serious conservation challenge in many countries in sub Saharan Africa. Though, a variety of conflict management strategies have been taken for mitigation, the impact is not much, crop-raiding is still increasingly alarming especially in mount Cameroon national park periphery due to increase in human settlement. The main objective of this study was to assess the crop-raiding activity of elephants in the national park. Data collection method was focused on sampling the affected village communities by monitoring the feeding and foraging activities of elephants on cropland. The research data collection was done for a period of four months, during this period, elephants were monitored and their feeding and foraging activities were recorded from 8:00 am – 6:00 pm on different cropland. However, the study revealed crop-raiding behavior of the elephants significant, X2 = 18.55 df=8 P=0.017, X2 = 17.64 df=8 P=0.024, X2 = 10.04 df=8 P<0.05, X2 = 9.10 df=8 P<0.05 on photo-period, landscape, elephant trails, and affected villages respectively. Maize (Zea mays) 30%, cassava (Manihot escaulenta) 24%, and banana (Musa acuminata) 21% were the most raided crops by the elephants, while oil palm (Elaeis guineensis) 15% and plantains (Musa sapientum) 10% were the least. More so, cropland destruction distance from human residence recorded a significance, X2 = 29.75 df=20 P<0.05, and X2 =46.34 df=10 P=0.000 on farm-size estimate, and the day-period respectively. The destruction of cropland by the elephants was done during the morning, afternoon, and evening periods respectively and the most frequent distance of destruction from human homes, above 100 meters recorded 28%, and 81-100 meters recorded 15% respectively. Though, the scale of destruction was rated low 51%, and high 34% respectively, it was still very high (15%) in some farms. Humanelephant conflict at the periphery of mount Cameroon national park can be mitigated with elephant translocation to other national parks within the country.

Revisão: atividades biológicas, antioxidante e fitoquímica de Musa spp.

ABSTRACT: Banana (Musa spp.) is a food with high nutritional value. Studies about its compounds have increased considerably due to the antioxidant and biological activities of the fruit. Thus, this article synthesized and organized data related to the phytochemical constituents, as well as antioxidant and biological activities of Musa acuminata, Musa balbisiana and Musa paradisiaca, and evaluated the mutual influence and correlation of these activities. A bibliographic review was performed using the scientific databases Google Scholar, SciELO, Periódicos CAPES, Scientific Electronic Library Online (SciELO), Science Direct, PubMed and Scopus, applying the following terms: Musa spp., antioxidant, biological and phytochemical activities, combined by the Boolean operator AND. A total of 28 articles were selected from 2017 to 2022. The results indicated that bananas are rich in flavonoids, showed good performance in DPPH and FRAP antioxidant assays and have antibacterial, anticancer and antifungal potential. Previous literature reported that phytochemical constituents improved antioxidant performance, thereby enhancing the biological activities described.

Quantitative Effects of Drying on Ripe and Unripe Plantain Using Convective Dryer

This paper reports the effect of convective heat on plantain (Musa paradisiaca). Ripe and unripe plantains were bought from Eremi-adale local market in Ado-Ekiti, Nigeria. The samples were washed, peeled, sliced into mass sizes of 20g each, and load into the chamber of a fabricated convective dryer. Samples were removed from the chamber after every hour for measurement to determine their moisture losses. The plantain samples were dried at various drying time and with regulated drying temperatures of 333K, 343K, and 353K. Results of the laboratory analysis review that, the viable microbial counts decrease when the drying temperatures increase. Ripe samples were found to have higher percentage of crude fibre, fat and protein, than the unripe samples while unripe samples have higher percentage of carbohydrate and ash than the ripe samples, at the drying temperatures. It was equally reported from the proximate analysis test that, the percentage amount of moisture content, carbohydrate and crude fibre decreases when the regulated drying temperatures increase while the amount of protein, fat and ash increases with an increase of the regulated drying temperatures.

Glucomannan Potential of Banana Corms (Musa paradisiaca) as Prebiotics

Glucomannan Potential of Banana Corms (Musa paradisiaca) as Prebiotics

Nematicidal activity and in vitro radical scavenging from Piper cumbricola and Piper eriopodon

Plant-parasitic nematodes are considered difficult to control and cause oxidative stress in host plants, thus affecting agricultural crops. In Musa paradisiaca crops, the most abundant and with the greatest impact are Radopholus similis, and Meloidogyne spp. The control method most used is chemical nematicides, usually nonspecific and harmful. In this study, objective was determined antioxidant activity and nematicidal activity from Piper cumbricola and Piper eriopodon. The results for radicals-scavenging of the ethanol extract at 500 ppm of leaf from P. cumbricola were 94% DPPH• and 92.7% in ABTS•+ and for extract of leaf from P. eriopodon at 500 ppm were 64.9% DPPH• and 67.6% in ABTS•+. The nematicidal activity was determined on Radopholus sp. and Meloidogyne spp. Mortality percentages of crude extracts above 60% were obtained after 48 h in all treatments. Fraction 3 rich in 2,4-dimethoxy-5,6-methylenedioxy-1-(2-propenyl) benzene, from P. cumbricola and fraction 4 rich in gibbilimbol B (4-[3É)-decenyl] phenol), from the P. eriopodon, showed the highest biocidal activity on Meloidogyne spp. (70–100%) and Radopholus sp (35–100%). In conclusion, the species P. cumbricola and P. eriopodon can be an efficient strategy for the control of endoparasites Radopholus spp. and Meloidogyne spp with potential antioxidant on Musa paradisiaca crops.

Effectiveness Of Banana Nangka (Musa Paradisiaca Linn) Skin as A Natural Coagulant In Reducing Turbidity Of River Water

Effectiveness Of Banana Nangka (Musa Paradisiaca Linn) Skin as A Natural Coagulant In Reducing Turbidity Of River Water

The gastroprotective role of yellow kepok Banana (Musa x Paradisiaca L. Var. Kepok) peel extract and influence on markers of oxidative stress: Malondialdehyde and nitric oxide

Background/Aim: Flavonoids, tannins, saponins and polyphenols in yellow kepok banana (Musa x paradisiaca L. var. kepok) peel potentially could be a solution for peptic ulcer prevention. This study aimed to prove the efficacy of kepok banana peel extract as gastroprotective by analysing the number of gastric ulcers and markers of oxidative stress - malondialdehyde (MDA) and nitric oxide (NO). Methods: The study was performed on 33 female Wistar rats aged 3-4 months, weighed 100-250 g. Rats were divided into 3 groups: Musa Paradisiaca Var Kepok 1 (MPVK1) treatment group, Musa Paradisiaca Var Kepok 2 (MPVK2) and control group (K). In MPVK1 kepok banana peel extract at a dose of 80 mg / 200 g body weight (BW) was given and the MPVK2 group dose was 160 mg / 200 g BW. The gastritis induction was performed by using 5 % acetylsalicylic acid at a dose of 1500 mg/kg BW. MDA examination by HPLC method, NO examination by ELISA method and macroscopic examination by counting the number of ulcers on the gastric mucosa was performed. Results: The results showed that the lowest average MDA level, as well as the highest average NO level was in the MPVK2 group 3.27 and 286.17, respectively. The highest mean number of ulcers was in the control group 3.55. By analysing all the results it can be concluded that there is a significant difference in the average levels of MDA (p = 0.013), NO (p < 0.001) and the number of ulcers (p < 0.001) in the three groups. Conclusion: Banana peel extract was proven to be effective as a gastroprotective through markers of MDA, NO and the number of ulcers in Wistar rats.

Anaerobic Fermentation of Kepok Banana (Musa Paradisiaca) Peels with Different Levels of Tapioca for Reducing Their Fiber Components

Banana peel is restricted to use as feedstuffs because it has a high crude fiber content. The reduction of crude fiber can be done by anaerobic fermentation such as silage making. Soluble carbohydrates are needed as an energy source for microorganisms in ensilage process. Tapioca is one of soluble carbohydrates that can be used to improve silage quality. The objective of this study was to evaluate effect of tapioca levels on the fiber fraction of kepok banana peel silage (Musa paradisiaca). A completely randomized design was used in this study, with 4 treatments and 5 replications, namely T0: without tapioca, T5: 5% tapioca, T10: 10% tapioca, T15: 15% tapioca. Variables observed were the content of NDF (%), ADF (%), hemicellulose (%), cellulose (%), and lignin (%).Collected data was analyzed by analysis of variance and if it had a significant effect, it was continued with Duncan's multiple range test. The results of analysis of variance showed that the level of tapioca had a highly significant effect (P<0.01) on NDF, ADF, hemicellulose, cellulose, and lignin. DMRT showed that the lowest NDF content was at T15 with an average of 48.06%, the lowest ADF was found at T15 with an average of 20.20%, the lowest hemicellulose was found at T15 with an average of 27.46%, the lowest cellulose was found at T10 with an average of 7.98% and the lowest lignin against T15 with an average of 12.09%. In conclusions, 1) Different levels of tapioca was can reduce ADF, NDF, hemicellulose, cellulose, and lignin in kepok banana peel silage, 2) The use of 10% tapioca reduced the highest kepok banana peel silage fiber fraction.

EFFECT OF TRADITIONAL PROCESSING METHOD AND LEAF-PACKAGING ON SENSORY CHARACTERISTICS OF OLÈLÈ, A STEAMED COWPEA PASTE

Musa paradisiaca, Tectona grandis and Thalia geniculata leaves used in the past as wrapping materials of Olèlè (steamed dough of cowpea enriched to the shrimps and other condiments), are being abandoned in favor of metal cans. This situation contributes to the lost of identity of this traditional food product. Two traditional processing methods which differ in the dehulling techniques are practiced to obtain Olèlè also called Magni magni or Moin moin. The objective of this study was to determine the effect of processing methods and wrapping materials on sensory characteristics of Olèlè and their consumer acceptability. For this purpose, sensory difference and overall acceptability tests and a sensory profile analysis were conducted. Thus, Olèlè differently wrapped was produced the day of the sensory evaluation and appreciated by sensory panelists. Panelists clearly distinguished Olèlè according to the processing method. Sixteen representative descriptors were identified to profile Olèlè. The leaves used for wrapping Olèlè had a significant effect on its sensory characteristics noted by the consumer panel with clearly distinct sensory profiles (p ≤ 0.05). The overall acceptability test revealed that the Olèlè wrapped in Musa paradisiaca leaves is the most appreciated, followed respectively by those wrapped with Tectona grandis leaves, Thalia geniculata leaves and one packaged in recycled tin cans.

Histomorphological evaluation of the combined therapeutic potential of Carica papaya and Musa paradisiaca on indomethacin induced gastric injury

Background: Medicinal plants are often used for the preparation of remedies for the treatment of several ailments especially in rural areas. Objective: The study investigated the combined effect of Carica papaya (pawpaw) and Musa paradisiaca (plantain) leaves extract on the stomach walls of albino rats against indomethacin induced gastric ulceration. Materials and Methods: Twenty-five (n-25) albino rats were weighed and divided randomly into five groups. Each group consisted of five (n-5) rats. Group A served as negative control and received rat feeds and water ad libitum. Group B received feeds and a single dose of indomethacin (25 mg/kg body weight) via orogastric administration and organs were harvested 4 hours after administration. Group C rats were administered with Carica papaya leaf extract (250 mg/kg body weight) daily for 14 days. Group D was administered with Musa paradisiaca leaf extract (250 mg/kg body weight) for 14 days. Group E received combined extract of Carica papaya (250 mg/kg body weight) and Musa paradisiaca (250 mg/kg body weight) daily for 14 days. All the animals were allowed access to feed and water. The animals in groups C-E fasted for 24 hours and were administered with a single dose of indomethacin (25 mg/kg body weight). Four hours later, the animals were sacrificed under chloroform inhalation, organs harvested, processed and stained with haematoxylin and eosin for histomorphological evaluation. Result: The result of the study shows that the single dose of indomethacin caused gastric ulceration within 4 hours. Musa paradisiaca leaf extract ameliorated the effect of indomethacin on the stomach. Combination of Carica papaya and Musa paradisiaca leaves extract exacerbated the effect of indomethacin on gastrointestinal tract ulcers. Conclusion: The practice of using combined extract of Carica papaya and Musa paradisiaca should be avoided in ulcer patients or individuals on indomethacin therapy

Preparation of Carboxymethyl Cellulose from Musa paradisiaca Pseudo Stem Using an Alkaline Treatment

Carboxymethyl cellulose (CMC) extraction from Musa paradisiaca (MP) pseudo stem by alkaline treatment and their properties were examined in the current research work. One of the most well-known types of lignin biomass waste that is readily available globally is MP. In many nations, including Taiwan, Sri Lanka, the Philippines, India, and the Philippines, these plants have been used for traditional reasons. Whole plant parts have been used as food, including the pseudo-stem, flower buds, trunk, fruits, and leaves. Sequestration of cellulose was attained by alkaline treatment and bleaching from raw fibers. Cellulose fiber is a biodegradable, naturally occurring, and renewable polymer that is used in a variety of industries, including the food, paper, cosmetic, and pharmaceutical sectors. The cellulose obtained from forest and agricultural residue has numerous advantages such as being environmentally safe, recyclable, and economically feasible respectively. The main process of cellulose extraction from MP pseudo stem are digesting process using a digester, bleaching, and neutralization which shows a zero-waste process. The alkali treatment takes less time to get a final product whereas enzyme treatment, and steam explosion treatment takes high energy and more cost. Hence, cellulose extract from alkaline treatment is economically feasible and environmentally friendly.

Identification and Prevention of Microbial Contaminants in Musa paradisiaca Tissue Culture

Banana (Musa spp.) is an economically vital fruit crop in Malaysia and therefore, micropropagation was applied to meet the market demand for disease-free seedlings. However, microbial contamination is a significant obstacle in micropropagation techniques. In this research, the microorganisms that were present in the banana culture were characterized and the efficacy of antimicrobial and antifungal agents to inhibit contaminants was evaluated. Three bacterial and two fungal isolates were isolated from the contaminated culture. Klebsiella pneumoniae, Klebsiella quasipneumoniae, and Klebsiella variicola were identified by molecular identification based on the 16S rDNA sequence. The gram-staining method confirmed all three bacteria were gram-negative. Oxidase and catalase tests showed the presence of cytochrome oxidase system and catalase enzyme in all bacteria. The bacteria can also hydrolyze starch, ferment sugars, and reduce sulfur from the amylase test. Phenotypic identification of fungi revealed the presence of conidia and hyphae, indicating the presence of Colletotrichum spp. and Aspergillus spp. In fungi characterization, Colletotrichum gloeosporioides and Aspergillus flavus were detected. Chloramphenicol was identified as an effective antibacterial agent from the disc diffusion method. Fluconazole was a potent antifungal agent by screening the sterilizing agents. The findings may potentially lead the way for the implementation of reducing the contamination rate in banana micropropagation.

Physical and Chemical Properties of Organic Fertilizer from Banana (Musa Paradisiaca) Leaf and Stem with Effective Microorganism Activactors (EM4)

Physical and Chemical Properties of Organic Fertilizer from Banana (Musa Paradisiaca) Leaf and Stem with Effective Microorganism Activactors (EM4)

Evaluation of Functional and Chemical Properties of Composite Flour made from Unripe Plantain (Musa Paradisiaca) and Cocoyam (Colocasia Esculenta) and Assessment of Consumers’ Acceptability of Amala

The study evaluated the functional and chemical properties of composite flour produced using unripe plantain and cocoyam and consumer acceptability of amala. Unripe plantain and cocoyam tests acquired from Orie-ugba market in Umuahia were washed, stripped, cut and dried in a stove for 24 h at 60 0C albeit the cocoyam cuts were drenched for 6 h with irregular difference in water after each 2 h. The doused cocoyam was rewashed, depleted and whitened for 4 minutes followed by drying in a broiler at 57±3 oC and processing to get flour test. The two flours (plantain flour: cocoyam flour), were formed into various extents, 40:60: 50:50 and 60:40. The control was 100 % plantain. The examples were exposed to examinations utilizing standard techniques. The aftereffects of the functional properties showed that the mass thickness went from 0.77 to 0.91 g/ml, gelatinization limit 8-12 enlarging record 29.12 to 34.02 while water ingestion limit went from 1.29 to 3.64 g/ml. The pH values went from 5.88 to 6.75. Test B(100% cocoyam flour) had the most noteworthy flavonoid content of 49.75 mg while test A (100 percent plantain flour) had the least worth (0.67 mg). The carotenoid content went from 0.73 to 48.82 µg. Test B was fundamentally unique (p<0.05) from different examples regarding all phenolics. Test A was most liked.

Allelopathic Effects of Some Fruit Plant Species with Weeds

Aqueous extracts of seven fruit plant species viz., banana (Musa paradisiaca), Indian gooseberry (Phyllanthus emblica), jack fruit (Artocarpus heterophyllus), guava (Psidium guajava), mango (Mangifera indica), litchi (Litchi chinensis), wood apple ((Aegle marmelos) were tested for germination, radical and plumule growth of barnyard grass and green amaranth. The lowest germination percentage (9.5 and 14.4%), plumule (3.94 and 0.92 cm) and radicle length (0.825 and 0.495 cm) of barnyard grass and green amaranth seedlings were obtained in seed treated with wood apple aqueous extract due to presence of some toxic compounds or other inhibitory materials in the species. One of these plant extract which performed the best i.e. wood apple leaves extract has the potential for use as an alternative crop as a herbicide (protectants) against barnyard grass and green amaranth weed species.

Morphological Diversity of Fungal Strains Responsible for Dessert Banana Rot, Musa Sapientum (Musaceae) Produced in the South Comoe Region on Ivory Coast

Aims: The banana dessert grown in different regions of the world, encounters important difficulties that cause it to lose its marketability especially because of the diseases related to conservation. The objective here is to identify the strains responsible for fungal diseases of bananas when it is stored.
 Study Design: This study was undertaken in order to ensure the competitiveness of the dessert banana from Ivory Coast on the international market which is threatened by the recurrent problem of post-harvest rot.
 Place and Duration of Study: Agrovalorisation Laboratory, Agroforestry Training and Research Unit, Université Jean Lorougnon GUEDE Daloa Côte d'Ivoire, between February 2021 and March 2022.
 Methodology: The study involved 120 bananas divided into two batches of 10 hands each, one with signs of necrosis and the other with no signs. Banana fragments (crown, epicarp and explant) were deposited on the growing media at several distinct points and slightly embedded in the agar. The resulting colonies were transplanted successively until a pure strain was obtained from a single mushroom colony per petri dish.
 Results: A total of 11 different genera were identified from 105 isolates. 57 are from necrotic bananas and 36 from bananas with no signs of necrosis. Fungal strains isolated there are: Trichoderma sp. (15%), Fusarium sp. (1%), Scytalidium sp. (39%), Mucor sp. (1%), Scopulariopsis sp. (1%), Alternaria sp. (4%), Aureobasidium sp. (1%), Aspergillus of the Glaucus group (10%), Cladosporium sp. (2%), Pseudallescheria sp. (6%) and Chrysosporium sp. (20%). No strains of the genus Colletotrichum musea responsible for anthracnose that can develop on both green and ripe fruit have been isolated. However, morphological characterization has not among to identify several other species (12) especially those not sporulating.
 Conclusion: This diversity of isolated strains in this work is identical to that most frequently isolated and cited in the literature.

PEMANFAATAN EKSTRAK KULIT PISANG KEPOK (Musa paradisiaca L) SEBAGAI BAHAN PENGAWET TELUR AYAM PETELUR

Eggs easily experience a decrease in quality caused by physical damage, as well as evaporation of water, carbon dioxide, ammonia, nitrogen, and hydrogen sulfide from inside the egg. This study aims to find out the effect of giving banana peel extract (Musa paradisiaca L). effect on egg shrinkage, egg pH, and percentage of rotten eggs. The data was analyzed using RAL with treatment 4 and repeat 5. In the extract of banana peel by spraying several doses each experiment (4, 8.5, 12, 16) gr / 100 ml. The results of the study for the best value of each variable from 0-14 days are only treated at (P2) with a value (1,57 ± 0,29 ), this indicates that the extract dose of 8.5 gr / 100 ml is better. In this study it can be concluded that egg preservation with the utilization of banana peel extract with the addition of different extracts and storage for 14 days has not been able to inhibit the quality of eggs shown by the value of egg weight shrinkage, egg pH, and percentage of rotten eggs. It can be used as a reference base for future research, and further research is needed on the use of banana peel extract as a utilization of banana skin extract as a preservative of laying breed chickens

DIFFERENCES IN CONSUMPTION OF JANTUNG PISANG (MUSA PARADISIACA) AND DAUN KELOR (MORINGA OLEIFERA) TOWARDS BREAST MILK PRODUCTION IN BREASTFEEDING MOTHERS IN THE WORK AREA OF PUSKESMAS NORTH BENGKULU

The number of exclusive breastfeeding in the world is only 44 percent. Exclusive breastfeeding coverage in Indonesia is 65.16 percent. This coverage is still far from the target in Indonesia of 95 percent. The coverage of exclusive breastfeeding in Bengkulu Province in 2020 is 73 percent, and the coverage of breastfeeding in North Bengkulu Regency is 73.81 percent. This study aims to determine the difference between consumption of musa paradisiaca and moringa oleifera on breast milk production in breastfeeding mothers in the Work Area of the North Bengkulu Regency Health Center. The study used experimental research methods. The population is postpartum mothers on the 5th day in December 2021 - January 2022 in the working area of the North Bengkulu Regency Health Center with a total of 57 people. The sample amounted to 46 respondents, 23 for the musa paradisiaca consumption group and 23 for the moringa oleifera consumption group. Respondents were taken by accidental sampling technique. Data were analyzed by bivariate analysis using independent T-test. Results: Most of the intervention group had parity multipara and grandemultipara (78.3%), almost half of them had secondary education (47.8%), and most of the families supported breastfeeding (60.9%), while in the comparison group, most of with parity multipara/grandemultipara (69.6%), more than half of them have basic education (52.1%), and most families support breastfeeding (69.6%); The average milk production in the musa paradisiaca group was 454.36 meanwhile, the moringa oleifera group was 358; There was a difference in consumption of jantung pisang (musa paradisiaca) and daun kelor (moringa oleifera) to increase breast milk production (p = 0.001). The results of this are expected to provide input for Puskesmas to increase promotion and motivation of exclusive breastfeeding mothers to improve maternal and child health.
 

AKTIVITAS ANTIBAKTERI EKSTRAK ETANOL 96% KULIT PISANG RAJA (Musa paradisiaca L) TERHADAP Escherichia coli

Banana peel is a material that can be used as a natural antibacterial because of its secondary metabolites content. The present study aimed to evaluate antibacterial activity of ethanol 96% extracted from banana (Musa paradisiaca L) peel against Escherichia coli. Result of phytochemical screening indicated that banana peel extract has alkaloid, flavonoid (tannin), and saponin compound that can act as antibacterial. Banana peel extract showed antibacterial activity that was proved by clear zone formed around disk paper. Sample of 64% extract concentration had the largest inhibition zone (9.6 mm) compared to sample of 16% and 32% concentration, inhibition zone of which was 4.4 mm and 6.26 respectively. One Way Anova analysis showed that sample of 64% concentration was significantly different from negative control, 16%, and 32% concentration. Nevertheless, there was no significant difference between 16% and 32% concentration.

The Effectiveness Of Kepok Banana ( Musa Paradisiaca. L) Consumption On Reducing First Trimester Igravidarum Emesis

Emesis gravidarum is a complaint that often occurs in pregnant women, especially in the first trimester. In addition to pharmacological drugs, emesis gravidarum can also be treated non-pharmacologically. This study aims to determine the effectiveness of the consumption of kepok bananas (Musa Paradisiaca Formatypica) on the reduction of first trimester emesis gravidarum in the Independent Midwife Practice (PMB) Susanti Pekanbaru City. The study was conducted from June to August 2021. The type of research used was pre-experimental with a one-group pre-post-test design which did not use a control group, but previously the group had pretest observations so that researchers could compare changes. The population of this study was 15 respondents. The sampling technique in this study was total sampling. The research instrument is a questionnaire sheet and bivariate data analysis. From the results of the study, it is known that the average emesis gravidarum before consuming banana kepok is 9.27 and the average emesis gravidarum after consuming banana kepok is 7.00. The results of the paired T-test showed the effectiveness of kepok banana consumption on decreasing first trimester emesis gravidarum with p value 0.000 < 0.05. From the results of this study, it is expected that pregnant women who experience emesis gravidarum can consume kepok bananas boiled for 40 minutes 3 times a day. Researchers suggest to health workers to be able to provide education about the benefits of kepok bananas to pregnant women in the first time who experience emesis gravidarum.